Central Nervous System Relapse Research Articles

Effectiveness, safety and utilization of cobimetinib and vemurafenib in patients with BRAF V600 mutant melanoma with and without cerebral metastasis under real-world conditions in Germany: the non-interventional study coveNIS.

Cobimetinib/vemurafenib combination therapy is approved for treatment of adults with unresectable or metastatic BRAF V600 mutated malignant melanoma (mM). The non-interventional post-authorisation safety study coveNIS collected real-world data on cobimetinib/vemurafenib treatment focussing on overall survival (OS), safety and utilization. MM patients with brain metastases are usually excluded from clinical studies. coveNIS observed 2 cohorts: mM patients without (Cohort A) and with cerebral metastases (Cohort B), aiming to close the data gap for the latter population. A direct comparison of the 2 cohorts was not intended. The primary effectiveness objective was OS; the safety objective was the incidence of all and of serious adverse events (AEs). Secondary objectives included progression-free survival (PFS), time to development of cerebral metastasis (Cohort A) and time to central nervous system relapse (Cohort B). All statistical analyses were descriptive. Between 2017 and 2021, 95 patients were included (Cohort A: 54, Cohort B: 41 patients) at 32 sites in Germany. Median OS was 21.6 months in Cohort A, 7.4 months in Cohort B. Median PFS was 6.9 months in Cohort A, 5.2 months in Cohort B. The proportion of patients experiencing any AEs was 83.3% (Cohort A) and 87.8% (Cohort B). The two most common AEs in Cohort A were 'diarrhoea' (37%), 'vomiting' (20.4%) and 'pyrexia' (20.4%); in Cohort B 'diarrhoea' (36.6%) and 'fatigue' (22%). In conclusion, the OS rates in Cohort A and Cohort B of coveNIS are in line with the OS data from other trials with BRAF/MEK inhibitors for mM. No new safety signals were observed.

CTNI-81. REAL-WORLD TREATMENT RESULTS OF RELAPSED PRIMARY CENTRAL NERVOUS SYSTEM LYMPHOMA TREATED BY MEDICAL THERAPIES

Abstract Recurrence of primary central nervous system lymphoma (PCNSL) is a condition which often leads to morbidity and mortality. Consensus regarding the optimal treatment regimen for relapsed PCNSL has not been achieved due to the rarity of the disease. In this study, we conducted a retrospective, single-institution study to investigate real world treatment results of relapsed PCNSL treated by several medical therapeutic regimens. Relapsed PCNSL patients treated at the authors’ institution were identified, and progression-free survival (PFS), overall survival (OS) were analyzed among patients treated by medical therapies. Patients treated by radiotherapy, treated for intraocular or systemic relapses, or best supportive care, were excluded from the survival analysis. 83 patients with first, 44 with second, 25 with third relapse were identified. Upon each relapse, number of patients who received medical therapies for CNS lesions, radiotherapy, treatment for intraocular or systemic relapse, and best supportive care were 48 (57.8%), 5(6%), 4(4.8%), 26(31.3%) (first relapse), 31(70.5%), 3(6.8%), 1(2.3%), 9(20.5%) (second relapse), 13(52.0%), 0, 1(4%), 11(44.0%) (third relapse), respectively. A total of 101 CNS relapses were treated by medical therapies, and PFS (months), OS (months) of the four groups of treatments (rituximab, methotrexate, procarbazine and vincristine [R-MPV], methotrexate [MTX], tirabrutinib, and others) were as follows. PFS: 13.0, 4.5, 2.7, 3.0, and OS: 70.0, 26.4, 51.2, 9.7 (all relapse). PFS: 12.7, 7.0, 3.0, 3.2, and OS: 58.9, 33.1, not reached(n/r), 16.1 (first relapse). PFS: 34.3, 3.9, 25.3, 1.5, and OS: n/r, 28.1, 25.5, 7.5 (second relapse). PFS: 10.1, 3.9, 2.4, 2.9, and OS: 14.9, 22.3, n/r, 8.1 (third relapse). In relapsed PCNSL, favorable PFS was observed in patients treated by R-MPV. Favorable OS was also observed in tirabrutinib, which might suggest that tirabrutinib failure were effectively salvaged by R-MPV. R-MPV might confer better prognosis in relapsed PCNSL.

Identification and Clinical Characterization of CNS Relapse in DLBCL Patients across 19 Prospective Phase 2 and 3 Trials - a GLA/ DSHNHL and LYSA Collaboration

Introduction: Depending on clinical and molecular risk factors, CNS relapse occurs in 1-15% of DLBCL patients (pts) and is associated with dismal outcomes. Despite its important role in further improving DLBCL therapy, a comprehensive and large-scale characterization of secondary CNS relapse remains challenging. Methods: We conducteda retrospective analysis of 7775 pts treated within 19 prospective German and French phase 2/3 trials to identify and characterize DLBCL pts with progression or relapse in the CNS. Pts with histology different from DLBCL (subtypes), not treated with anti-CD20 antibody, or displaying CNS involvement at diagnosis were excluded from the analysis. Results: Among 5289 eligible pts, 159 (3%) experienced progression or relapse in the CNS. Median age at diagnosis was 62 years (range: 19-80 years), 47% of pts were female. In 91% of all cases, reference pathology confirmed the diagnosis of DLBCL. At diagnosis, 28 pts (18%), 62 pts (39%), and 69 pts (43%) had a low (0-1 point), intermediate, and high CNS IPI (4-6 points), respectively. 133 pts received front-line therapy with R/O-CHOP, 19 pts with R-(Mega)CHOEP, and 7 pts with R/O-ACVBP. Following first-line therapy, 54% of pts achieved a CR/CRu. For 131 pts (82%), CNS progress/ relapse represented the first PFS event. Prior to the CNS event, salvage therapy was administered to 30 pts, including 11 pts treated with HDT/ASCT and one pt receiving allogeneic SCT. For 70 out of 158 pts (44%), CNS involvement was classified as intracerebral, 31% showed meningeal, and 3% intraspinal lymphoma involvement. In 22% of pts, CNS involvement was classified as combined including 5 cases with eye involvement. The CNS event occurred as progression without prior CR/ CRu of disease in 61 out of 159 pts (38%). For 155 pts it could be specified that 25% had an isolated progress in the CNS while 12% showed both CNS and concomitant systemic progress. 35% of pts showed an isolated CNS relapse while 28% suffered from a combined relapse. 82% of all CNS events occurred within the first two years after randomization while 29 pts (18%) experienced a late CNS event after 24 months. Notably, 46% of pts with low CNS IPI developed a late CNS event compared to 9% with high CNS IPI at diagnosis (Fisher exact, p<0.001). During the course of disease, 138 pts (87%) showed extranodal lymphoma involvement outside the CNS. The most frequently involved extranodal sites were bone (34%), gastro-intestinal tract (21%), soft-tissue (21%), kidney/ adrenal gland (20%), lung (19%), and liver (18%). In general, pts with CNS event had poor outcomes with a median OS of 3.4 months (95% CI 2.9-4.2) and a 2-year OS of only 15% (10-22%). While sex and initial (CNS) IPI had no impact on OS, we observed significantly worse OS for pts older than 70 years at diagnosis (log rank, p<0.001). OS was poor regardless of the site of CNS manifestation. Pts with isolated CNS disease demonstrated significantly better OS than pts with concomitant systemic involvement (p=0.023). Pts with CNS events occurring later than 24 months from randomization did not show improved OS compared to pts with early relapse/ progression (p=0.19). Treatment categories were reported for 150 pts. 95 pts received immunochemotherapy (IC), 30 pts in combination with radiotherapy (RT). More precisely, 69 pts received salvage therapies containing systemic MTX and 22 pts underwent consolidation with HDT/ASCT (73% of which had thiotepa-based conditioning regimens). Three pts received allogeneic SCT for consolidation. 28 pts were treated with RT alone (+/- intrathecal therapy (IT)). 27 pts received only IT, corticosteroids, or no treatment. Pts consolidated with HDT/ ASCT or allogeneic SCT had superior outcomes with a 3-year OS of 36% (20%-66%) compared to 18% (7.5%-44%) for pts receiving IC and RT, and to 9.7% (3.9%-24%) and 9.5% (2.8-32%) for pts treated with IC or RT alone, respectively ( Fig. 1). Overall, pts achieving a CR after CNS event (38/159, 24%) showed a 3-year OS of 52% (37-73%). Conclusions: This large study including more than 5000 DLBCL pts all treated on prospective clinical trials highlights the unmet medical need to improve the outcome of DLBCL pts suffering from CNS relapse. About one third of pts who underwent transplantation showed long-term survival in contrast to all other pts displaying very dismal outcomes. Novel strategies including targeted therapies and CAR T cells will have to challenge the survival rates reported here.

Favorable Outcome of Abbreviated R-CHOP in Patients with Primary Testicular Lymphoma

Background Primary testicular lymphoma (PTL) is a rare type of extranodal large B-cell lymphoma with an increased risk of relapse mostly involving the contralateral testis or central nervous system (CNS). To minimize the risk of relapse, Vitolo et al. (2011) introduced a multimodality approach in limited stage PTL including radical orchiectomy, 6 cycles of rituximab, cyclophosphamide, doxorubicin, vincristine and prednisolone (R-CHOP) with 4 intrathecal methotrexate (MTX IT) administrations and radiotherapy of the contralateral testis. In limited stage diffuse large B-cell lymphoma, without involvement of the testis, 4 cycles of R-CHOP proved non-inferior to 6 cycles of R-CHOP (Poeschel et al. 2019; Persky et al. 2020). However, it is unknown whether the number of cycles of R-CHOP can be reduced in PTL. Therefore, we aimed to evaluate the impact of the number of R-CHOP cycles on outcome in PTL patients in the Netherlands. Methods PTL patients ≥18 years, Ann Arbor stage I-II, diagnosed in 2014-2021, who received at least 3 cycles of R-CHOP were identified in the Netherlands Cancer Registry, with survival follow-up through 2022. Patients with CNS involvement at diagnosis were excluded. Treatment modalities were categorized as 3 cycles R-CHOP or 6 cycles R-CHOP. Patients who received 4, 5 or more than 6 cycles of R-CHOP were included in the 6 cycles modality. The primary endpoints were progression-free survival (PFS), and overall survival (OS). PFS was defined as the time between end of primary treatment and relapse, or death from any cause, whichever came first, and OS was defined as the time between end of primary treatment and death from any cause. The secondary endpoint was cumulative incidence function (CIF) of CNS relapse, defined as the number of CNS relapses divided by the total number of patients in the study population at risk for a specific time. Uni- and multivariable analyses were conducted to establish independent predictors of risk of relapse and mortality among patients who received 3 cycles of R-CHOP versus 6 cycles of R-CHOP. Uni- and multivariable analysis to calculate risk of relapse and mortality after adjustment for the baseline and treatment characteristics was performed using Cox regression. Results A total of 139 patients were identified: median age, 68 years (range, 37-86 years); stage I, 68%; IPI 0, 87%. Of these patients, 43 received 3 cycles R-CHOP and 96 received 6 cycles R-CHOP (number of cycles 4:4%; 5:6%; 6 or more: 90%). Patients with stage I disease more commonly received 3 cycles of R-CHOP compared to patients with stage II ( p<0.01; Table 1). In combination with R-CHOP, most patients received MTX IT (93%), high-dose MTX (4%) or did not receive prophylaxis (4%). The median number of MTX IT cycles was 5 in patients who received 3 cycles R-CHOP and 6 in patients who received 6 cycles R-CHOP ( p=0.08). Of the patients who received 3 cycles R-CHOP, 29% received <4 MTX IT cycles, compared to 11% in patients who received 6 cycles R-CHOP ( p=0.02). Overall, 82% received radiotherapy, 5% orchidectomy and 13% no consolidation. The median follow-up from end of treatment was 42 months (inter quartile range [IQR], 22-70 months). Overall response rate (ORR; partial remission or greater) for patients who received 3 cycles R-CHOP and 6 cycles R-CHOP were similar (79% versus 86%, respectively, p=0.27). The 5-year PFS and OS were 66% and 75%, respectively. Regarding 3 versus 6 R-CHOP, the 5-year PFS and OS were similar, i.e. 65% versus 67% ( p=0.81) and 73% versus 76% ( p=0.69), respectively (Figure 1). In univariable analysis, risk of relapse and mortality were similar for patients who received 3 cycles of R-CHOP or 6 cycles R-CHOP. In multivariable analysis, none of the covariables influenced the risk of relapse or mortality. The 5-year CIF of CNS was 6.7%, with a median time from end of treatment to CNS relapse of 25 months. 6 (14%) out of 43 PTL patients with 3 cycles R-CHOP relapsed to CNS, and 1 (1%) out of 96 patients with 6 cycles R-CHOP ( p<0.01). The number of MTX cycles was not related on developing a CNS relapse (p=0.81). Conclusion In this nationwide population of PTL patients, nearly one-third of patients received 3 cycles of R-CHOP instead of 6 cycles. No difference in survival was observed between the two groups. These data support investigating reduction of systemic treatment from 6 cycles of R-CHOP in this patient group.

Whole Exome Sequencing Analysis of Diffuse Large B-Cell Lymphoma That Progressed to Central Nervous System

Background: Recent sequencing analyses have identified distinct genetic subtypes of diffuse large B-cell lymphoma (DLBCL). The MCD subtype, characterized by MYD88 L265P and CD79B gene mutations, is frequently found in DLBCL that progresses to the central nervous system (CNS), known as secondary CNS lymphoma (sCNSL) (Ollila, Blood 2021). In addition, the MCD subtype is also frequently found in primary CNS lymphoma (PCNSL) (Radke, Nat commun 2022). Therefore, we hypothesized that specific genetic alterations that are present in the initial DLBCL tumors are associated with their progression to the CNS. We aimed to investigate i) the clinical impact of genetic subtypes of DLBCL and ii) genomic mutations that may be associated with sCNSL. To this end, genetic alterations in DLBCL samples at diagnosis that later developed into sCNSL were evaluated using whole-exome sequencing (WES). Methods: A total of 44 patients with DLBCL who developed sCNSL after receiving standard rituximab-containing chemotherapy between 2009 and 2020 were identified from five institutions. sCNSL was diagnosed on the basis of imaging and/or pathological findings. Genomic DNA (gDNA) was extracted from formalin-fixed, paraffin-embedded tumor samples obtained at the initial diagnosis of DLBCL. Finally, 26 of the 44 samples with sufficient gDNA were subjected to WES at BGI Genomic Co. Ltd. Single-nucleotide variants and short indels were detected using Mutect2 and filtered as described in Figure 1. Genetic subtypes were determined using the LymphGen algorithm (https://llmpp.nih.gov/lymphgen/index.php). The association between the clinicopathological features and genetic subtypes was also evaluated. In addition, recurrently mutated genes (>10% in our cohort) were identified and their alteration frequencies were compared with those in a representative general DLBCL cohort (N=574, available in the article by Schmitz, NEJM 2018) and PCNSL cohort (N=30, whole genome sequencing performed, available in the article by Radke, Nat Commun 2022) (Figure 1a). Results: The median age of the 26 patients was 69 years (range, 34-87). At the time of CNS progression, 54, 27, and 19% of the patients had parenchymal CNS disease, extraparenchymal CNS disease, and both, respectively. Immunohistological analysis showed that the non-germinal center B-cell-like (GCB) type, as defined using the Hans algorithm, and dual expression of MYC and BCL2 (DEL) were identified in 65% and 69% of patients, respectively. The median overall survival (OS) from CNS relapse was 16 months (95% confidence interval, 2-30). WES analysis showed that the median mean coverage depth of the 26 samples was 140 (range, 53-299). The median mapping rate was 94% (range, 80-99). As expected, the most frequently mutated genes in our cohort were MYD88 (50%), PIM1 (50%), BTG2 (31%), and CD79B (31%), corresponding to the MCD subtype. The LymphGen algorithm classified the 26 samples into MCD (n=12, 46%), EZB (n=5, 19%, including one with a composite feature of ST2), BN2 (n=1, 4%) and “not classified” (n=8, 31%) (Figure 1b). The CNS-IPI risk, DEL status, and CNS relapse sites did not differ among the genetic subgroups. In addition, univariate analysis showed that non-GCB status, DEL status, and genetic subtype at initial diagnosis did not influence OS. Next, we shortlisted 38 genes whose mutations were identified in three or more samples (>10%) of our cohort as well as in >10% of the PCNSL cohort (by Radke, Nat Commun 2022). We further selected genes that were less frequent (<3%) in the general DLBCL cohort and identified several genes, such as MUC16 and FAT4, that were more enriched in PCNSL and our sCNSL cases (Figure 1a). Metascape analysis (https://metascape.org/gp/index.html#/main/step1) revealed that the top three enriched processes associated with these genes were sensory organ development, cell adhesion via plasma membrane adhesion molecules, and morphogenesis of epithelium. Conclusion: Our study confirmed that MCD was a major genetic subtype of DLBCL that developed sCNSL. We identified recurrently mutated genes that were common in both sCSNL and PCNSL but not in the general DLBCL cohort; these genes may be associated with CNS progression. Validation of our results and investigation of the functions of these genes will help to understand the mechanisms of CNS relapse and develop more accurate markers to predict sCNSL. *Suzuki T and Yokomori R equally contributed to this study.

Chemotherapy-Free Combination of Blinatumomab and Ponatinib in Adults with Newly Diagnosed Philadelphia Chromosome-Positive Acute Lymphoblastic Leukemia: Updates from a Phase II Trial

Background Blinatumomab and ponatinib demonstrated efficacy in patients with Philadelphia chromosome (Ph)-positive acute lymphoblastic leukemia (ALL). A chemotherapy-free regimen combining both drugs in the frontline setting may mitigate the risk of toxicities and the need for hematopoietic stem cell transplantation (HSCT). Methods In this phase II trial, patients ≥18 years of age with newly diagnosed Ph-positive ALL were eligible. They were required to have a performance status of ≤2, total bilirubin ≤2x the upper limit of normal (ULN), and ALT/AST ≤3x the ULN. Patients with uncontrolled cardiovascular disease or clinically significant central nervous system (CNS) comorbidities (except for CNS leukemia) were excluded. Patients received up to 5 cycles of blinatumomab in combination with ponatinib, followed by ponatinib maintenance for ≥5 years. Ponatinib 30mg daily was given during Cycle 1 and decreased to 15mg daily once a complete molecular response (CMR) was achieved. Patients also received 12 doses of prophylactic intrathecal (IT) chemotherapy with alternating cytarabine and methotrexate. The primary endpoint was the CMR rate. Secondary endpoints included response rates, safety measures, event-free survival (EFS), and overall survival (OS). Results Between June 2018 and May 2023, 62 pts with newly diagnosed Ph-positive ALL were treated. Baseline characteristics are shown in Table 1. Twenty-two patients were in complete remission (CR) at the start of therapy. Among 40 patients evaluable for hematologic response, 39 (98%) achieved CR/CRi; 1 patient had early death. Among 55 patients evaluable for molecular response, 37 (67%) achieved CMR after 1 cycle, and 46 (84%) achieved CMR at any time. Forty-seven patients were evaluated for measurable residual disease (MRD) by next-generation sequencing at a sensitivity level of 10 -6, of whom 43 (91%) were found to have negative MRD. Five of these patients with undetectable MRD by NGS had low-level BCR:ABL1 transcripts detected by PCR at the same time (ranging from 0.01% to 1.23% IS). Four of them had p190 transcript and one had p210. The median follow-up was 17 months (range, 2-61 months). Six patients (10%) relapsed after a median of 21 months of remission (range, 8-24 months): two relapsed in the bone marrow (one with acquired E225V mutation), one had an extramedullary-only relapse (Ph-negative and MYC-rearranged relapse), and three had a CNS-only relapse (after 20, 22, and 23 months). Four patients died (one from intracranial hemorrhage, one from post-procedural hemorrhage, one from brain aneurysm, and one following CNS relapse with intracranial edema and septic shock). One leukemia-related death occurred on study; the estimated 2-year EFS and OS rates were 77% and 89%, respectively (Figure 1). Only one patient underwent HSCT in first CR due to persistently low-level BCR:ABL1 positivity. Among the 52 patients in ongoing remission without HSCT, the median duration of response was 16 months (range, 2-61). Most adverse events were grade 1-2 and were consistent with the known toxicity profile of the two agents. Ponatinib was discontinued in two patients due to possibly related adverse events (cerebrovascular accident and coronary artery stenosis in one patient each). Conclusions The chemotherapy-free combination of blinatumomab and ponatinib is safe and effective in newly diagnosed Ph-positive ALL, with high rates of MRD negativity. Encouraging duration of remission and OS has been observed without the need for HSCT.

A Phase IB/II Study of Blinatumomab in Patients with B-Cell Acute Lymphoblastic Leukemia (ALL) and B-Cell Non-Hodgkin Lymphoma (NHL) As Post-Allogeneic Blood or Marrow Transplant (alloBMT) Remission Maintenance

Background: AlloBMT can be curative as consolidation for high risk B ALL and NHL. However, transplant-related toxicity and disease relapse limit survival. Post-transplantation cyclophosphamide (PTCy) as graft-versus-host disease (GVHD) prophylaxis limits GVHD and facilitates alternative allograft sources. Following PTCy, cellular immune reconstitution is favorable for strategies to augment anti-tumor immunity. Blinatumomab (blina) is effective in the treatment of CD19+ ALL and NHL. Blina leads to T cell activation that may enhance post-transplant tumor-specific T cell responses, leading to a more potent graft-versus-tumor effect. A study of 21 B ALL pts demonstrated the feasibility of post-transplant blina but did not improve survival when pts universally remained on immunosuppression for at least 1 cycle of treatment (Gaballa. Blood. 2022). We present results of a phase Ib/II trial to assess the tolerability and preliminary efficacy of blina as post-alloBMT remission maintenance in B-cell ALL and NHL in pts off immunosuppression. Methods: Pts ≥1 month-old with high risk CD19+ B ALL or ≥18 years-old with NHL who underwent alloBMT with PTCy were eligible. Pts had to be 60-180 days post-transplant with count recovery and in remission. Pts had to be off immunosuppression for ≥4 weeks prior to treatment, and without a history of grade ≥3 acute GVHD or severe chronic GVHD. Pts could receive 2 cycles of blina if they had evidence of disease (including MRD) at their pre- and/or post-transplant evaluations but otherwise received 1 cycle. Blina was given as a continuous infusion at 9 mcg/day on C1D1-7 and 28 mcg/day on C1D8-28 and C2D1-28. Results: The study closed to accrual on January 31, 2023 following enrollment of 42 pts (26 male/16 female) with a median age of 54 (Range 30-73). Among enrolled pts, 19 had Ph-negative B ALL and 23 had B-cell NHL. All pts underwent reduced-intensity conditioning alloBMT using a regimen of fludarabine, cyclophosphamide, and total body irradiation. Median prior lines of therapy were 2 (range 1-6). Additional transplant details are presented in Table 1. All B ALL pts were in an MRD-negative CR by flow cytometry at a sensitivity of 0.01% at alloBMT. All pts received a single cycle of therapy. Pts started blina a median of 137 days post-transplant (range, 90-182). Four pts failed to complete a full cycle due to G4 transaminitis (1), G4 neutropenia (1), relapse (1), and patient preference in the setting of tremors (1). Grade 3 or 4 adverse events felt to be at least possibly related to the study drug included G3 neutropenia (7%), G4 neutropenia (19%), anemia (5%), G3 ALT (5%), G4 AST (2%), G3 AST (2%), and neurotoxicity (7%). Two pts (5%) developed chronic GVHD following blina requiring the resumption of immunosuppression. At a median follow-up of 40 months post-alloBMT, the 3-year relapse-free survival is 73% (95% CI 54-85%) due to a 24% (95% CI 12-39%) incidence of relapse and a 4% (95% CI 0-17%) incidence of non-relapse mortality, as shown in Figure 2. All 3 (100%) relapsed B ALL pts and 2/6 (33%) relapsed B NHL pts presented with CNS involvement. Four pts with CNS relapse (80%) had CNS involvement prior to alloBMT. Among 2 pts who died without relapse, 1 was unrelated to alloBMT, while the other died of therapy-related myeloid neoplasm. Data on biomarkers including changes in T cell subpopulations in both BM and PB, and co-signaling molecule expression will be presented. Conclusions: Post-alloBMT maintenance therapy with blina is feasible with minimal toxicity in pts off immunosuppression. Initial survival outcomes are promising with the majority of relapses involving the CNS. A randomized trial of maintenance with blina after alloBMT with PTCy is needed to confirm efficacy in this high-risk population.

Hyperleukocytosis in Patients with Acute Myeloid Leukemia Characteristics and Outcome, a Single-Center Experience

Background Hyperleukocytosis is the condition where Acute myeloid leukemia (AML) is presented with white blood cell counts equal to or greater than 100,000. A small proportion of AML patients are presented with this condition which is associated with significant morbidity and mortality caused by related serious complications including leukostasis, tumor lysis syndrome (TLS) and disseminated intravascular coagulation. Hyperleukocytosis is a hematological emergency requiring immediate intervention. In this retrospective study we describe the general characteristics, cytogenetics, mutational profile, treatment given, and outcome of AML patients having hyperleukocytosis at diagnosis. Methods Data were retrieved from the clinical data base of our tertiary cancer center (National Center for Cancer Care and Research, Doha, Qatar). All patients with AML diagnosed during the period January 2017 through December 2021 were included. Results A total of 186 AML patients were included. Twenty-one patients (11.5%) were presented with hyperleukocytosis. Males were more predominant 13/21 (62 %) and more than half of the patients had an Asian origin 52%. The median age for the group was 40.0 years (18-89). Complete blood count (CBC) showed median hemoglobin of 9.2g/dl, white blood cells of 176x10^3/uL and platelets 6x10^3/uL. the median percentage of the blast in the peripheral blood was 71 % and 72 % in bone marrow. Bone marrow cellularity was high in all the cases 100%. Bone marrow dysplasia was assessed with dysgranulopoiesis observed in 24%. All patients had de novo AML. In these patients the diploid KT was most common cytogenetic findings (57%), followed by CBF recurrent cytogenetics abnormalities in 4 patients (19%). FLT 3-ITD was positive in 7 patients (33%) and NPM1 mutation in 5 patients (28%). Hydroxyurea (HU) was used as cytoreductive therapy in 90% of patients. More than half of the patients 11/21 (52%) were admitted to intensive care unit (ICU). One patient had CNS relapse. Seven patients (33%) underwent allogenic bone marrow transplant. Progression occurred in 6 patients 28 (median1.4 years) and Overall survival in this cohort was 76 % (median1.9 year) and the average duration of follow-up of 24.8 months. Early death within 30 days observed, with median time to death 4 days (1-12) among those who died. Conclusion One of ten AML patients are presented with hyperleukocytosis. Most of our AML patients with hyperleukocytosis were young males. This is most probably related to the young general population in our country. All patients had hypercellular marrow with high blast percentage. Diploid Karyotype, CBF rearrangements, FLT 3-ITD mutation and NPM1 mutation were frequent in this cohort. Most of the patients developed complications requiring intensive care admission. Hydroxyurea was the first choice for cytoreduction. Both disease progression and mortality were relatively high (28% and 24 % respectively) and occurred very early, within less than a week from presentation. Early diagnosis and immediate management are mandatory to tackle the complications of this hematological emergency and improve morbidity and mortality.

A Single Center, 10-Year Experience of CALGB-10403 Regimen in AYA Population with Philadelphia-Chromosome Negative Acute Lymphoblastic Leukemia

INTRODUCTION: The use of pediatric-inspired regimens for the treatment of acute lymphoblastic leukemia (ALL) has now become the standard of care in adolescents and adults (AYA). One such regimen, CALGB 10403, had higher rates of event free survival (EFS) and overall survival (OS) compared with historical controls using adult ALL regimens. It was shown to be feasible and efficacious in fit patients up to the age of 40 (Wendy Stock et al., Blood 2019). In 2012, based on emerging data on the improved efficacy of pediatric-inspired regimens in AYA patients, CALGB 10403 was adopted as the standard-of-care regimen in this population at Karmanos Cancer Institute (KCI), an adult cancer treatment center. Here we report our single center, real world experience of using this regimen in a Philadelphia chromosome negative (Ph-) AYA population, approximately 10 years after its adoption. METHODS: We conducted a retrospective chart review of consecutive AYA (ages 18-39) patients with Ph- ALL treated with CALGB 10403 regimen between January 2012 and June 2023 at KCI. Patients who received alternative regimens due to distance from KCI were excluded. Baseline demographic, clinical and molecular characteristics were noted. High-risk cytogenetics were defined as KMT2A rearrangements, hypodiploidy with a chromosome number ≤43, and complex karyotype. Testing for Ph-like ALL was not available in most patients. Beginning in 2019, clonoSEQ assay was used to test for minimal residual disease (MRD), with MRD negativity defined at a threshold of less than 10 -4. Incidence of adverse effects and treatment related mortality were reported to describe safety. Complete response (CR) rate, OS and PFS were used as efficacy outcomes. Kaplan-Meier curves were used to estimate OS and PFS. RESULTS: A total of 17 Ph- AYA patients were treated at KCI with a median age at diagnosis of 25 years (range 18-34). Males and females had a near equal representation (47% and 53%). The patients were predominantly White (64%). The majority of patients had a good ECOG performance status of 0 or 1 (88%). The diagnosis was B-ALL in 9 (53%) and T-ALL in 8 (47%) patients. High risk cytogenetics were present in 3 (80%) of the evaluable patients. None of the patients had CNS involvement at diagnosis. Baseline laboratory parameters expressed as medians were bone marrow blast percentage 80%, WBC count 9.2 x1000/mm 3, hemoglobin 8.4 g/dL, platelets 109 x1000/mm 3, and LDH 480. The median duration of follow-up was 54 months. 15 (88%) patients had CR with induction, and MRD was negative in 4 (57%) of the 7 evaluable patients. 2 (12%) patients had primary refractory disease. One of the patients with refractory disease underwent further therapy with blinatumomab, inotuzumab, CAR-T and allogeneic stem cell transplantation and is alive at 16 months from diagnosis. Another underwent salvage with hyper-CVAD and allogeneic stem cell transplant, and is currently alive at 88 months from diagnosis. Two additional patients were MRD positive after induction (course I) but subsequently attained MRD negativity. One of these eventually relapsed 7.5 months from diagnosis with a mixed phenotypic (T/myeloid) leukemia and died at 10 months, while the other is currently under treatment. An additional patient with CR1 and unknown MRD status had CNS relapse at 35 months, underwent successful hyper-CVAD, reintroduction of intrathecal chemotherapy and allo-HSCT salvage and is alive at 122 months. The 5-year PFS and OS were 74.5% and 94% respectively and the medians were not reached for both. Noteworthy adverse effects include neutropenic fever (65%), liver function tests (LFT) abnormalities (70%), and neuropathy from vincristine (70%). Peg-asparaginase administration was associated with pancreatitis in 12%, thromboembolism in 30% and hypersensitivity reactions in 24% requiring switching to alternative forms of asparaginase products (erwinia and Rylaze). These toxicities were manageable and there were no treatment-related deaths in our cohort. CONCLUSIONS: The pediatric-inspired regimen CALGB 10403 was safe and efficacious in our AYA Ph- ALL population with no deaths due to treatment and a 5-year overall survival of 94%. Toxicities, especially from peg-asparaginase, should be closely monitored. While most patients will attain durable remission/cure, the minority with refractory or relapsed disease can still be successfully salvaged to achieve long term survival.

A Randomized, Open-Label, Phase 3 Study of Acalabrutinib in Combination with Rituximab and Reduced Dose CHOP (R-miniCHOP) in Older Adults with Untreated Diffuse Large B-Cell Lymphoma (ARCHED / GLA 2022-1)

Background Diffuse large B-cell lymphoma (DLBCL) is the most common lymphoma subtype, and its incidence increases with age. Approximately 40% of patients with DLBCL are older than 70 years. Since the addition of the anti-CD20 antibody rituximab to CHOP regime (cyclophosphamide, doxorubicin, vincristine, and prednisone) prognosis in elderly patients has improved but still remains worse compared to their younger counterparts. Adequate dosage of chemotherapy in older adults is limited by comorbidities/frailty, especially in patients >80 years of age. An attenuated chemotherapy regimen, R-miniCHOP, has been evaluated in prospective trials and seems to provide a good balance between safety and efficacy in this vulnerable patient population (Peyrade et al, 2011). However, even with this regime, outcomes remain modest with 2-year overall survival at 50-60%, underlining the need for more effective treatment in this population. Acalabrutinib is a selective, irreversible, second-generation small molecule inhibitor of Bruton Tyrosine Kinase (BTK) with a more favorable safety profile compared to first generation BTK inhibitors. Although, not yet approved for the treatment of DLBCL, acalabrutinib showed promising results both as a single agent (Strati et al, Haematologica 2021) and in combination with full dose R-CHOP (Davies et al, ASH 2022), in patients aged up to 80 years. Furthermore, acalabrutinib carries the potential of improved efficacy in specific subgroups. The activated B-cell like (ABC) DLBCL subtype has been shown to depend on chronic active B-cell receptor signaling involving many downstream kinases including BTK. Additionally, the genetically defined subgroups MCD/C5, N1, and BN2/C1 and also may serve as potential predictive biomarkers for acalabrutinib. Study design and endpoints ARCHED is an investigator initiated, randomized, multicenter, open-label, phase III trial of R-miniCHOP with or without acalabrutinib in older adults with untreated DLBCL. Patients in the standard arm will receive 6 cycles of R-miniCHOP every 21 days followed by 2 cycles of rituximab alone, while patients in the experimental arm will receive the same regimen and additionally acalabrutinib 100 mg p.o. twice daily from day 1 to day 21 for 8 cycles (Figure 1). The primary endpoint of the study is investigator assessed progression-free survival (PFS). Secondary endpoints include overall survival, PFS per blinded independent review, event-free survival, outcomes according to cell of origin and molecular genotype, response rates, duration of response, progression, relapse and central nervous system (CNS) relapse rates as well as toxicity. Key eligibility criteria Patients are eligible for enrolment if they are >80 years old or >60 years old and ineligible for full-dose R-CHOP according to investigator assessment after standardized simplified geriatric evaluation and are diagnosed with untreated CD20+ DLBCL according to the 2017 WHO classification. Primary mediastinal lymphoma, high grade B-cell lymphoma and follicular lymphoma 3B as well as concurrent diagnosis of indolent lymphoma is allowed, but Richter's transformation is an exclusion criterion. Ann Arbor stage I patients can be included only in the presence of concomitant bulky disease (≥ 7.5 cm). Further exclusion criteria are CNS involvement, stroke or intracranial hemorrhage in the past 6 months and relevant organ dysfunction. An ECOG performance status score of 0 - 2 is required for enrolment but an ECOG score of 3 is acceptable if lymphoma associated. Statistical analysis With an expected 5% drop out rate, we aim to recruit 330 patients (165 in each arm) to achieve 80 % power at a 5 % significance level (two-sided) to observe a PFS difference of 15 % in favor of the experimental arm. An interim analysis for efficacy comparing PFS between the two treatment arms will be performed with n=200 patients and 1 year follow-up for the last patient, with approximately 50% of events. Additionally, an interim analysis for safety regarding treatment completion rates and all-cause mortality will take place when 92nd patient in each group has completed the sixth R-mini-CHOP cycle or died. ARCHED is an academic study of the German Lymphoma Alliance and is coordinated by the Saarland University Clinical Trials Unit. This study is funded by AstraZeneca GmbH. The trial is approved in the EU and is open for recruitment in Germany. (EU-CTN: 2022-501187-18-00, NCT05820841).

Evaluating the Impact of Prophylactic Intrathecal Chemotherapy in Diffuse Large B Cell Lymphoma (DLBCL) Patients with High Central Nervous System International Prognostic Index (CNS-IPI) Scores: A Comprehensive Review and Meta-Analysis

Introduction Diffuse large B cell lymphoma (DLBCL) with a high CNS-IPI score poses an increased risk for relapse involving the central nervous system (CNS). Despite various studies seeking to validate the use of CNS prophylaxis, including intrathecal chemotherapy, results have been equivocal. This ambiguity may be partly attributed to the lack of prospective data, patient heterogeneity, limited sample sizes, and outdated methodologies in pre-rituximab studies. Consequently, administering CNS prophylaxis with intrathecal chemotherapy is not a standardized practice, and decisions are often based on individual factors such as anatomical location, disease stage, and specific case characteristics. Methods This systematic review and meta-analysis were conducted and reported using the PRISMA guidelines. A thorough search was conducted across multiple online databases, including Google Scholar, Science Direct, PubMed, Cochrane, CINAHL, EMBASE, ProQuest Dissertation and Theses, ISI web of knowledge, PsycINFO, and Embase for articles on this topic. The date range of the articles included was between 2013-2023 and were limited to English language, peer-reviewed articles, cohort studies, retrospective studies & randomized controlled trials. The inclusion and exclusion criteria for studies helped to determine suitable studies Results Out of 179 studies retrieved from the database search and 2 from other studies' reference lists, 6 met the inclusion criteria for qualitative and quantitative analysis. Data from 2209 patients in these 6 studies was analyzed using a random-effects model to perform a subgroup analysis of the benefits and risks of prophylactic intrathecal chemotherapy for patients with DLBCL and a high CNS-IPI score. The results demonstrated a significant improvement in overall treatment success, with a difference of 0.60 (95% Confidence Interval, 0.45 to 0.93) on a 0-10 Visual Analogue Scale (VAS). The heterogeneity of the studies was determined to be significant (P=0.02), further substantiating the positive impact of prophylactic intrathecal chemotherapy on the therapy success rate for DLBCL patients with high CNS-IPI scores. Conclusion Our review elucidates that intrathecal chemotherapy as a prophylactic measure can reduce the rate of CNS relapse and enhance overall survival for patients with DLBCL possessing a high CNS-IPI score. However, it underscores the necessity to thoroughly assess each patient's unique clinical situation when determining if intrathecal chemotherapy is the appropriate therapeutic approach.

Clinical Features and Therapeutic Evaluation of Central Nervous System Involvement in Pediatric Anaplastic Large Cell Lymphoma

Objective：To analyze the clinical features of central nervous system involvement (CNS3) in pediatric anaplastic large cell lymphoma (ALCL) and evaluate the efficacy of CNCL-ALCL-2017 protocol for the treatment of CNS3. Methods：The clinical data of 215 pediatric ALCL patients ≤18 years old enrolled in the Chinese Children's Cancer Group (CNCL) between April 2017 and March 2023 were collected sequentially. All enrolled patients staging and CNS layering were according to the IPNHLSS staging system and treated with CNCL-ALCL-2017 protocol (modified BFM-ALCL99 protocol). The clinical features at diagnosis and treatment outcomes of CNS3 patients were analyzed. All patients were followed up until June 30, 2023. Data were collected using a unified information platform. Associations between patient characteristics were analyzed with Chi-squared or Fisher's exact tests. Eventfree survival (EFS) and overall survival (OS) curves were estimated according to the KaplanMeier method and compared by Logrank test. Furthermore, statistical analysis was performed using SPSS 22.0 software. P<0.05 was considered statistically significant. Results: Among the 215 ALCL pediatric patients, 17 (7.9%) had CNS3, including 13 males and 4 females with median age of 8.0 (range 1.0-14.0) years. In this patients, brain parenchyma and spinal cord involvement were found in 58.8% (10/17) patients on imaging, with space-occupying lesions in 7 cases and abnormal signals on MRI in 4 cases. Concurrent space-occupying lesions and abnormal signals on MRI was detected in 1 case. Cerebrospinal fluid (CSF) positivity was detected in 35.3% (6/17) patients, including 2 cases with positive ALK gene and 5 cases with positive flow cytometry, with 1 case positive for both. Cranial nerve deficits such as facial nerve palsy, visual or hearing impairment were observed in 23.5% (4/17) patients. Concurrent CSF, imaging and cranial nerve abnormalities were present in 5.9% (1/17), while two of this were present in 29.4% (5/17). Isolated CSF positivity without other abnormalities was detected in 23.5% (4/17). Pathological subtypes included common type (76.5%, 13/17), histiocyte-rich variant (5.9%, 1/17), small cell variant (5.9%, 1/17), others (11.8%, 2/17). Immunohistochemistry showed ALK + in 94.1% (16/17) and CD3 + in 76.5% (13/17). Concurrent ALK gene positivity in both peripheral blood and bone marrow was detected in 64.7% (11/17), with 58.8% (10/17) positive in both samples. The median follow-up of all patients was 35.4 months (range 0.5-74.9). All CNS3 patients had stage IV disease and were treated with regimen D (with 5 g/m 2 methotrexate). The 3-year OS was 94.3%, 98.2% and 93.3% for CNS1 (144, 67.0%), CNS2 (54, 25.1%) and CNS3 (17, 7.9%) patients, respectively; the 3-year EFS was 85.6%, 90.3% and 86.7%, respectively. No significant differences were found among the three groups. The 3-year OS and EFS for the whole cohort were 95.1% and 84.7%, respectively, also with no significant differences from the CNS3 group. Of the CNS3 patients, 1 was lost to follow-up after the first course, 1 died during treatment, and the interim CR rate was 75.0% (12/16). CSF conversion was achieved in 3/6 (50%) CSF-positive patients. 6.25% (1/16) patient had CSF ALK gene re-positivity during maintenance and persistent positivity despite additional ALK inhibitor alectinib and intrathecal therapy. In the CNS1 group, 2 cases were lost to follow-up and 4 cases died. The relapse rate was 11.4% (16/140), and the rate of central nervous system relapse was 2.1% (3/140). Additionally, the rate of CNS1 relapse was slightly higher but not statistically significantly different for CNS2. Conclusions: CNS involvement is relatively rare in pediatric ALCL. Detection rate of CNS3 can be improved by CSF flow cytometry and gene screening. The prognosis of CNS3 was significantly improved with CNCL-ALCL-2017 protocol, which may be related to the increased dose of methotrexate in the protocol. The short follow-up time and the small number of cases in this group may affect the results. Furthermore, CNS relapse rate of CNS2 was not markedly higher compared to CNS1. Keywords: Anaplastic large cell lymphoma; Pediatric; Central nervous system; Clinical features; Prognosis

Outcomes in Mantle Cell Lymphoma with Central Nervous System Involvement - a Dual Center Study

Background Central nervous system (CNS) involvement is a rare complication (<5% of cases) of mantle cell lymphoma (MCL) and is associated with poor outcomes, highlighting the need for novel treatment approaches. We report the outcomes of a large cohort of patients (pts) with CNS MCL from Mayo Clinic and Memorial Sloan Kettering Cancer Center (MSKCC). Methods MCL pts with CNS involvement seen at Mayo Clinic and MSKCC between 1/2000-1/2021 were included. CNS involvement was defined by histologically confirmed CNS MCL, CSF analysis demonstrating lymphoma cells, and/or neuroimaging findings compatible with CNS lymphoma. Medical records were reviewed for baseline characteristics, treatment, and outcomes. First-line MCL chemotherapy was categorized into higher intensity chemotherapy (i.e., anthracycline-based +/- high-dose cytarabine), moderate intensity chemotherapy (i.e., bendamustine-based regimens or single agent chemotherapy), and other. CNS treatment regimens were categorized as intrathecal (IT) therapy alone, systemic therapy (with CNS penetration such as IV cytarabine or IV methotrexate) with/without IT therapy, regimens with Bruton's tyrosine kinase inhibitors (BTKi), chimeric antigen receptor T cell (CAR-T) therapy, or radiation alone. Kaplan-Meier method was used for time to event analysis. Forest plots were developed using univariable Cox proportional hazards models. Results Seventy patients were included in the cohort, 34 from MSKCC and 36 from Mayo Clinic. Median age at MCL diagnosis was 65 years (range 56-72) and 52 were male (74%). MIPI score was available in 60 pts: low (n=10, 17%), intermediate (n=20, 33%), and high (n=30, 50%) risk. First line therapy included: higher intensity chemotherapy (n=42, 60%), moderate intensity chemotherapy (n=25, 36%) and other (n=3, 4%). Twenty-five (36%) pts underwent autologous hematopoietic cell transplantation in CR1. Median time from initial MCL diagnosis to CNS involvement was 24 months (m) (range 0-167). Four (6%) pts had CNS involvement at initial diagnosis. Abnormal CNS imaging was reported in 53 (76%) pts: leptomeningeal (n=37), leptomeningeal and parenchymal (n=4), parenchymal (n=8), orbital (n=4). The most common regimen following CNS diagnosis was systemic therapy with or without IT therapy (n=34, 54%) followed by treatment including BTKi (n=13, 21%), IT alone (n=10, 16%), radiation alone (n=3, 5%), and treatment including CAR-T (n=3, 5%). Three patients elected hospice care and four patients had missing/unknown CNS treatment. The overall CNS response to therapy was available in 54 patients: CR in 22 (41%) pts, PR in 8 (15%), SD in 11 (20%), and PD in 13 (24%) pts. Of the 70 patients, 63 died. Median follow up was 6.9 years (range: 1.6-11.2) from initial MCL diagnosis and 2.1 years from CNS diagnosis (range: 0.4-7.9). Median OS from MCL diagnosis was 3.4 years (95% CI: 2.4-4.6). In univariable Cox models, sex, stage, performance status, Ki67, or first line systemic chemotherapy type were not significantly associated with OS from MCL diagnosis. Low risk MIPI score (score < 5.7) was associated with favorable OS (HR 0.31, 94% CI: 0.12-0.77; p value 0.01) compared to high risk. First-line treatment and treatment intensity were not associated with a significant difference in OS. Median PFS for the first CNS-directed therapy was 2.4 m (95% CI: 1.7-4.3). Cause of death was disease-related in a majority (n=49, 78%) of pts and therapy-related in 10% (n=6). The remaining 8 deaths had cause of death reported as missing or other (13%). Median OS from CNS involvement was 5.1 m (95% CI: 3.3-10.0) (Figure 1). When assessing OS from time of CNS diagnosis, treatment regimens incorporating BTK inhibitors were associated with a more favorable OS compared to systemic therapy +/- IT therapy (HR=0.37, 95% CI: 0.16-0.89, p value=0.03) (Figure 2). Conclusions Our dual center series confirms patients with CNS involvement by MCL have poor outcomes. When evaluating OS from the time of CNS diagnosis, novel therapies, including BTKi and CAR-T, may be more effective than CNS-penetrant chemotherapy for treatment of CNS relapse suggesting newer therapeutic approaches are required to improve outcomes.

MO49-1 The efficacy of high-dose versus intrathecal methotrexate for DLBCL with high risk of CNS relapse: A multicenter retrospective study

MO49-1 The efficacy of high-dose versus intrathecal methotrexate for DLBCL with high risk of CNS relapse: A multicenter retrospective study

Methotrexate-Induced Subacute Combined Degeneration in Acute Lymphoblastic Leukemia with CNS Relapse May Be Reversible

Methotrexate-Induced Subacute Combined Degeneration in Acute Lymphoblastic Leukemia with CNS Relapse May Be Reversible

Cerebral Spinal Fluid Parameters Following CD19-Targeted Therapies in Children and Young Adults.

The presence of leukocytes in the cerebral spinal fluid (CSF) of patients with acute lymphoblastic leukemia may indicate a relapse in the central nervous system. CD19-directed immunotherapy may increase the blood-brain barrier permeability, leading to neurologic toxicity and infiltrate the CNS. We studied the CSF cell and protein content in 71 consecutive patients who received either CD19 chimeric antigen receptor T cells or blinatumomab. Responding patients had an incidence of 66% and 61% of pleocytosis following blinatumomab or chimeric antigen receptor T cells, respectively. CSF parameters did not correlate with toxicity or prior CNS disease. Routine CSF flow cytometry following immunotherapy to distinguish T-cell infiltration from CNS relapse should be considered.

High-Dose Methotrexate as CNS Prophylaxis in High-Risk Aggressive B-Cell Lymphoma.

CNS progression or relapse is an uncommon but devastating complication of aggressive B-cell lymphoma. There is no consensus regarding the optimal approach to CNS prophylaxis. This study was designed to determine whether high-dose methotrexate (HD-MTX) is effective at preventing CNS progression in patients at high risk of this complication. Patients age 18-80 years with aggressive B-cell lymphoma and high risk of CNS progression, treated with curative-intent anti-CD20-based chemoimmunotherapy, were included in this international, retrospective, observational study. Cause-specific hazard ratios (HRs) and cumulative risks of CNS progression were calculated according to use of HD-MTX, with time to CNS progression calculated from diagnosis for all patients (all-pts) and from completion of frontline systemic lymphoma induction therapy, for patients in complete response at completion of chemoimmunotherapy (CR-pts). Two thousand four hundred eighteen all-pts (HD-MTX; n = 425) and 1,616 CR-pts (HD-MTX; n = 356) were included. CNS International Prognostic Index was 4-6 in 83.4% all-pts. Patients treated with HD-MTX had a lower risk of CNS progression (adjusted HR, 0.59 [95% CI, 0.38 to 0.90]; P = .014), but significance was not retained when confined to CR-pts (adjusted HR, 0.74 [95% CI, 0.42 to 1.30]; P = .29), with 5-year adjusted risk difference of 1.6% (95% CI, -1.5 to 4.4; all-pts) and 1.4% (95% CI, -1.5 to 4.1; CR-pts). Subgroups were underpowered to draw definitive conclusions regarding the efficacy of HD-MTX in individual high-risk clinical scenarios; however, there was no clear reduction in CNS progression risk with HD-MTX in any high-risk subgroup. In this large study, high-risk patients receiving HD-MTX had a 7.2% 2-year risk of CNS progression, consistent with the progression risk in previously reported high-risk cohorts. Use of HD-MTX was not associated with a clinically meaningful reduction in risk of CNS progression.

Craniospinal Irradiation for CNS Leukemia: Rates of Response and Durability of CNS Control.

Craniospinal irradiation (CSI) is used in the management of leukemia patients with central-nervous-system (CNS) involvement, though the data on response and local control are limited. Given the radioresponsiveness of leukemia, we hypothesized that response to CSI would be high, but CNS control would be influenced by control of systemic disease. This retrospective, single-institution analysis included consecutive pediatric and adult patients between 2009-2021 with leukemia that underwent CSI for CNS involvement, defined as presence of blasts (i.e., >0%) on CSF flow cytometry. Endpoints included CNS response rate (RR), CNS local recurrence (LR), progression-free survival (PFS), and overall survival (OS), which were estimated from start of CSI. The probability of CNS LR was summarized using a cumulative incidence estimate, where death without LR was considered a competing risk. The probabilities of OS and PFS were obtained using Kaplan-Meier estimates. Among the 39 eligible patients (43% AML, 49% ALL, 8% blast-phase CML), most were male (59%). All had CSF confirmation of disease. Median age at CSI was 31 years (range 7-67). CSI (protons 54%, photons 46%) was utilized early within the CNS disease course (median 0 CNS relapses prior to CSI). Twenty-five patients (64%) received CSI immediately prior to a stem-cell transplant (SCT), of which 21 (84%) had TBI conditioning to a median dose of 12 Gy (range 2-13.2). Patients treated with CSI alone received a higher CSI dose (median 18 Gy; range 10.8-24) than those treated with SCT consolidation (median 12 Gy; range 10.8-24). Fifteen patients had CSF-positive disease immediately prior to CSI; all 14 of those assessed for response (RR 100%) had confirmed clearance of blasts at a median of 23 days (range 7-197) from CSI start. With a median follow-up of 48 months (range 0.4-123) for survivors, 2-year PFS and OS estimates were 32% and 43%, respectively. Only 5 CNS relapses were noted (2-year CNS LR of 14%). All CNS relapses either occurred after (n = 4) or concurrently (n = 1) with a systemic relapse. In Cox regression univariate models, age, sex, time to CNS disease, positive CSF immediately prior to CSI, and SCT did not show demonstrable evidence of association with CNS LR. However, systemic relapse after CSI (HR 5.9, 95% CI 2.5-13.8, P<0.0001) and systemic disease at the time of CSI (HR 3.9, 95% CI 1.6-9.5, P = 0.003) were associated with higher risk of CNS LR. No grade-3+ acute toxicity was seen during CSI. CSI is a well-tolerated and effective treatment option for patients with CNS leukemia. Though CNS local recurrence was modest, there was a high risk of systemic relapse and/or death. Control of systemic disease, both before and after CSI, may be important for CNS local control, and raises consideration that CNS recurrence may reflect reseeding from the systemic space.

Initial Experiences in Adolescents and Young Adults with T-Cell Acute Lymphoblastic Leukemia/Lymphoma Treated with the Modified BFM 2002 Protocol in a Resource-Constrained Setting

T-cell acute lymphoblastic leukemia/lymphoblastic lymphoma (T-ALL/LBL) in adolescents and young adults (AYAs) is a clinically aggressive malignancy and life-threatening at diagnosis. Intensive chemotherapy protocols, inspired by the Berlin-Frankfurt-Münster (BFM) regimen, along with central nervous system (CNS) prophylaxis, have achieved a 75 to 85% 5-year disease-free survival rate. However, in cases of marrow and CNS relapses, second-line chemotherapy is usually ineffective. This study aimed to assess the safety and efficacy of the BFM 2002 protocol and to correlate clinical profiles and prognostic factors with survival outcomes in AYA T-ALL/LBL patients. We retrospectively analyzed data from T-ALL/LBL patients treated at the Department of Medical Oncology, Sri Aurobindo Institute of Medical Sciences (SAIMS), Indore, between 2018 and 2021. Twenty-one patients aged 15 to 29 years were studied for their clinical course and laboratory parameters over 36 months. Diagnosis and risk stratification were performed following the guidelines of the BFM 2002 protocol. All patients received treatment and monitoring according to this pediatric-inspired protocol. The median age of the patients was 17 years (range: 15–28 years). Eleven patients presented with mediastinal lymph node enlargement, 10% exhibited CNS involvement, and none had testicular involvement. Eleven patients had marrow blasts greater than 25%, indicative of acute lymphoblastic leukemia. All 21 patients were treated according to the intensive modified BFM 2002 protocol and achieved morphological remission after a median follow-up of 24 months (range: 18–36 months). Seventeen patients achieved minimal residual disease (MRD) negativity post-induction. MRD at day 33 showed a significant association with the probability of disease relapse (p = 0.0015). There were five deaths (24%), one due to toxicity and four due to relapse. The study recorded an 18-month overall survival of 76%. These results were achieved despite financial constraints. Data were entered into a spreadsheet, and statistical analysis was performed using IBM SPSS version 23. Continuous data are presented as ranges and medians, while categorical variables are shown as percentages and numbers. A chi-squared test for association, with a significance level set at p &lt; 0.05, was conducted as indicated. AYA T-ALL/LBL requires intensive treatment regimens. With biological characterization of LBL/ALL and close therapy monitoring, encouraging outcomes can be achieved even in resource-limited settings.

Real World Utilization of Cranial or Craniospinal Radiation in Adult Acute Lymphoid Leukemia Patients: Data from the Center for International Blood and Marrow Transplant Research

Though CNS involvement at diagnosis in adult acute lymphoid leukemia (ALL) is relatively rare (3-7%), >50 % of patients will develop CNS relapse without CNS-directed therapy. Radiation therapy is commonly used as part of stem cell transplant (SCT) conditioning. Historically, a cranial boost was given to reduce risk of CNS relapse. While a CNS boost is not a universal part of prophylaxis, CNS directed RT is used in patients at highest risk for CNS relapse following transplantation, typically those with CNS disease at diagnosis or after induction. There is little data on real world utilization of CNS directed radiation as part of SCT for adult ALL patients. The Center for International Blood and Marrow Transplant Research (CIBMTR) database was queried for adult ALL patients undergoing SCT between 2013 - 2019 who received TBI as part of their regimen where data was available on CNS directed RT. Patient demographics, pre-transplant response to induction, CNS status pre/post-transplant, and overall survival information were collected. Results were stratified by cranial irradiation (CNS-RT), craniospinal irradiation (CSI), or no cranial RT (nCRT). Radiation dose is not collected by the CIBMTR. The data presented here are preliminary and were obtained from the Statistical Center of the Center for International Blood and Marrow Transplant Research. The analysis has not been reviewed or approved by the Advisory or Scientific Committees of the CIBMTR. A total of 1240 patients were identified, of which 59 (5%) received CNS-RT, 2 (0.2%) received CSI, 989 (80%) received nCRT, and 190 (15%) had unknown CNS RT status. Median age was younger in patients receiving CNS-RT (26y, range 19-66y) or CSI (34y, 22-46y) compared to patients receiving nCRT (42y, 18-79y). Patients receiving CNS radiation had more advanced disease at time of transplant (17% requiring 3+ lines of induction before CR vs 50% vs 5%, respectively). 24% of CNS-RT patients and 50% of CSI patients had CNS disease at diagnosis compared to 7% of nCRT patients. 37% of CNS-RT patients and 100% of CSI patients had CNS disease prior to transplant compared to 11% of nCRT patients. Overall survival at 1-5 years was numerically higher with CNS-RT compared to no RT, though 95% confidence intervals overlapped at each follow up point. Data from the CIBMTR on real world utilization of CNS-RT or CSI in adult ALL patients suggest inconsistent practice patterns with 11% of patients without any cranial RT having CNS disease prior to transplant and 57% of CNS-RT patients having no CNS disease prior to transplant. These data offer an interesting analysis of current CNS radiation practice patterns in the past 10 years for adult ALL patients, though interpretation is limited by the retrospective nature of the study and by significant limitations of available data.