ALK-negative Anaplastic Large Cell Lymphoma Research Articles

Update on T-Cell Lymphoma Epidemiology.

T-cell lymphomas (TCLs) are a group of rare subtypes of non-Hodgkin lymphoma derived from mature T-lymphocytes. Recent updates in lymphoma classification based on the cell-of-origin pathogenesis have shed new light on TCL epidemiology and outcomes. Contemporary regional consortia and international studies, including those conducted recently in Asia and South America, have provided an updated delineation of the major subtypes across various global regions. Peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS), remains the most common subtype globally except in Asia, where extra-nodal NK-T cell lymphoma (ENKTL) has emerged as the most prevalent. Angioimmunoblastic T-cell lymphoma (AITL) is the second most common subtype globally except in South America where its incidence falls behind adult T-cell leukemia/lymphoma (ATLL) and ENKTL. ALK-negative anaplastic large cell lymphoma (ALCL) has been recognized as the second most common subtype in some parts of South America. Studies on the newly classified breast implant-associated ALCL (BIA-ALCL) are beginning to reveal its distribution and risk factors. Deciphering the epidemiology of TCLs is a challenging endeavor due to the rarity of these entities and ongoing refinement in classification. Collaborative efforts on prospective registries based on the most current WHO classifications will help capture the true epidemiology of TCL subtypes to better focus resources for diagnostic, prognostic, and therapeutic efforts.

Pooled analysis of pralatrexate single-agent studies in patients with relapsed/refractory peripheral T-cell lymphoma

AbstractPatients with relapsed or refractory (R/R) mature natural killer cell and T-cell lymphoma have limited treatment options. To evaluate pralatrexate’s performance and factors influencing its safety and efficacy in R/R peripheral T-cell lymphoma (PTCL), we performed a pooled analysis of data from 4 similarly designed, regulatory-mandated prospective clinical trials. Of 221 patients (median age, 59 years; 67.0% male) in the study population, 48.9% had PTCL not otherwise specified (PTCL-NOS), 21.3% angioimmunoblastic T-cell lymphoma, and 11.8% ALK-negative anaplastic large cell lymphoma (ALCL). Patients received pralatrexate for a median of 2.56 months (range, 0.03-24.18) and had a 40.7% objective response rate with a median duration of response of 9.1 months, progression-free survival 4.6 months, and overall survival 16.3 months. The most common treatment-related all-grade adverse events were stomatitis, thrombocytopenia, white blood cell count decrease, pyrexia, and vomiting. Subgroup exploratory analyses suggest improved efficacy with 1 prior line of chemotherapy vs 2 or ≥4 prior lines; PTCL-NOS or ALCL vs transformed mycosis fungoides; chemotherapy and transplant before pralatrexate vs chemotherapy alone or chemotherapy with other nontransplant treatments. In conclusion, these pooled analysis results further support using pralatrexate in patients with R/R PTCL. Prospective studies are needed to confirm the findings of subgroups analyses.

ALK-negative anaplastic large cell lymphoma with TP63 rearrangement

ALK-negative anaplastic large cell lymphoma with TP63 rearrangement

Erratum to: DUSP22-rearranged ALK-negative anaplastic large cell lymphoma is a pathogenetically distinct disease but can have variable clinical outcome.

Erratum to: DUSP22-rearranged ALK-negative anaplastic large cell lymphoma is a pathogenetically distinct disease but can have variable clinical outcome.

Primary Central Nervous System ALK-negative Anaplastic Large Cell Lymphoma, with TP53 Deletion

Abstract Introduction/Objective ALK-negative anaplastic large cell lymphoma (ALCL) primary to the central nervous system (CNS), is a sporadic and rare lymphoma, characterized by neoplastic T-cells which are CD30 positive and ALK negative. It has a male predominance, mostly affects old adults and usually displays supratentorial, single or multiple lesions. Methods/Case Report We report the case of a 57-year-old woman with medical history of breast cancer, S/P lumpectomy and radiation therapy, who came to our institution with confusion, partial aphasia and headache. MRI showed a thick-walled, irregular, ring enhancing mass in the periventricular white matter of the occipital and temporal horns of the lateral ventricle with surrounding vasogenic edema and mass effect. It was isointense to cortex on T1- and heterogeneously hyperintense on T2-weighted images with mild diffusion restriction in the enhancing portion. A left parieto-occipital decompressive craniotomy was performed and tissue was procured for diagnosis. The biopsy showed an infiltrating, angiocentric neoplasm, composed of large anaplastic cells, including hallmark cells with "horseshoe" nuclei, abundant eosinophilic cytoplasm and occasional perinuclear clearing. Large areas of necrosis and pericellular reticulin deposits of the vascular walls were also noted. On immunohistochemistry, the neoplastic cells diffusely expressed CD45, CD2, CD3, CD25, CD43, MUM1, and CD30, and were negative for ALK, CD20, CD79a, PAX-5, CD15, CD5, BCL-6, BCL-2, Granzyme B, GFAP, Pancytokeratin. In situ hybridization for EBER was negative. The proliferative index (Ki-67), while variable, was as high as 80%. TP53 deletion was detected by FISH in 100% of the cells analyzed. No rearrangements in the ALK or MYC genes was noted by FISH. Additional studies revealed a complex karyotype including loss of chromosomes 9 and 10, gain of chromosome 17 and a marker chromosome, and structural rearrangements involving chromosomes 4, 10, and 13. Previously reported rearrangements involving DUSP22 (6p25) and TP63 (3q28) were not identified. TCR gene rearrangement was also identified by PCR. High dose Cytarabine/Methotrexate, and radiation were not successful in controlling disease progression and home hospice was recommended. Results (if a Case Study enter NA) N/A Conclusion This is an infrequent type of primary CNS lymphoma with a poor prognosis and, while TP53 has been reported in sporadic, and cutaneous ALCL, to our knowledge, this is the first report of primary CNS ALK-negative anaplastic large cell lymphoma with TP53 deletion.

Genome-Wide CRISPR Screen Identifies ZNF451 Regulating Sensitivity to Topoisomerase 2 Inhibitors in Peripheral T-Cell Lymphoma Cells

Introduction: Despite the recent therapeutic developments for peripheral T-cell lymphomas (PTCLs), their prognosis remains dismal. Topoisomerase 2 inhibitors (TOP2i), which increase the amount of TOP2-DNA covalent complex and block DNA double-strand break repair, have long been used as key drugs in the treatment of PTCLs. The molecular mechanisms underlying sensitivity to TOP2i remain to be fully elucidated. Methods: To elucidate the cell-intrinsic genes affecting TOP2i sensitivity in PTCL cells, we performed whole-genome loss-of-function CRISPR screenings in adult T-cell leukemia/lymphoma (ATLL) cell lines. ST1 and KK1 cells were transduced with the Brunello CRISPR knockout pooled library targeting 19,114 genes (4 sgRNAs/gene) followed by puromycin selection. The transduced cells were then treated with etoposide (ETP), doxorubicin (DOX) or DMSO control for 8 days. The MAGeCK algorithm was used to rank the sgRNAs responsible for TOP2i sensitivity. Among the top 500 enriched genes, we further selected the those with at least 2 sgRNAs with a log2 fold change (TOP2i/DMSO) < -0.5 or >0.5 in both ST1 and KK1 cells as genes whose knockout conferred TOP2i sensitivity or resistance, respectively. Results: Using the whole genome loss-of-function CRISPR screen, we identified 3 genes and 2 genes whose knockout conferred ETP sensitivity and resistance, respectively. TOP2A, a known ETP target, was ranked as a top gene for ETP resistance, confirming the reliability of our screenings (Fig. 1). In the same way we also extracted 3 genes whose knockout conferred DOX sensitivity. Interestingly, zinc finger protein 451 (ZNF451) was identified as an overlapping gene whose knockout conferred sensitivity in both screens for ETP and DOX. ZNF451 is an E3 SUMO ligase and was previously reported to be an endogenous DNA repair factor for TOP2i-induced DNA double-strand breaks (Schellenberg et al. Science 2017). The role of ZNF451 in PTCL cells has not been previously reported, prompting us to focus on ZNF451 in further analyses. For a confirmatory experiments, we transduced sgRNAs targeting ZNF451 (sgZNF451) in ATLL cell lines. To see the knockout efficiencies of the sgZNF451, we performed immunoblot analysis by using anti-ZNF451 antibody and found three bands with different levels of reduction. To ensure whether the bands detected by the anti-ZNF451 antibody represented endogenous ZNF451 protein, we engineered the ATLL cell line with an HA-tag at the 5' UTR of the endogenous ZNF451 gene locus by CRISPR-mediated knock-in. Immunoblot analysis of sgZNF451-transduced engineered cells expressing HA-tag-ZNF451 by using anti-HA antibody showed almost the same pattern of the bands as shown in the blot by anti-ZNF451 antibody. Thus, we confirmed that sgZNF451 worked efficiently and concluded that post-transcriptional modification affected the stability of ZNF451 protein in ATLL cells. Next, we investigated the role of ZNF451 on cell viability. While sgZNF451-transduced ATLL cells did not differ from control sgRNA-transduced cells in terms of cellular proliferation under normal culture conditions, sgZNF451-transduced ATLL cells showed increased sensitivity to both ETP and DOX compared to control cells with statistical significance, confirming our screening results (Fig. 2). Importantly, sgZNF451-mediated sensitization to ETP and DOX was found not only in ATLL cells but also in other PTCL cell lines including ALK-positive and ALK-negative anaplastic large cell lymphoma (ALCL). Mechanistically, apoptosis and G2/M cell cycle arrest were induced at significantly higher frequencies by ETP treatment in ZNF451 knocked out cells compared to control cells. Given the role of ZNF451 in TOP2i sensitivity in PTCL cells, we investigated whether ZNF451 expression levels stratify the prognosis of PTCL patients treated with CHOP-like regimens. To test this, FFPE samples from 45 PTCL-NOS patients were used for Q-PCR analysis of ZNF451 mRNA but we did not find any correlation between the ZNF451 expression and prognosis. Conclusions: We performed unbiased genome-wide CRISPR/Cas9 library screens and identified ZNF451 as an important regulator of sensitivity to TOP2i in PTCL cells. Further studies are needed to determine whether measuring ZNF451 protein levels can be used as a biomarker in PTCL patients who are treated with TOP2i.

Brentuximab Vedotin in Combination with Nivolumab in CD30+ Malignancies Refractory to Brentuximab Vedotin

Introduction Brentuximab vedotin (BV), in combination with multi-agent chemotherapy, is considered a standard of care for newly diagnosed CD30+ lymphomas. Despite high reported efficacy, some patients fail to respond to initial BV exposure and many more eventually progress despite ongoing BV therapy. In addition to direct cytotoxicity, BV may also induce immunogenic cell death (Gardai, et al. Cancer Res 2015) and foster a reduction of regulatory T-cells (Herrera, et al. Blood 2018) that may synergize with immune checkpoint inhibitors. To date, the high response rates reported with BV and anti-PD-1 combinations have been limited to patients naïve to both of these agents (Advani, et al. Blood 2021). To address the more clinically relevant scenario of prior BV +/- anti-PD-1 exposure, we designed a study to evaluate the combination of BV and nivolumab in patients with CD30+ lymphoma refractory to prior BV, including those with prior anti-PD-1 therapy. We report the final safety, efficacy and correlative analysis of BV in combination with nivolumab in R/R CD30+ lymphomas refractory to BV. Methods We conducted an open-label trial (NCT01703949) involving patients 18 years and older with CD30+ lymphomas refractory to BV therapy. Refractoriness was defined as lack of disease response or progression within 6 months following a minimum of 2 cycles of BV. BV was given at 1.8 mg/kg in combination with nivolumab at 3 mg/kg every 3 weeks for 4 cycles. The primary endpoint was overall response rate (ORR). Secondary endpoints included complete response (CR) rate, progression-free survival, overall survival, time to next treatment, safety and tolerability and immune response biomarkers. Results As of July 27, 2023, 19 patients have enrolled and 17 have initiated therapy (Table 1). Fourteen patients had classical Hodgkin lymphoma (cHL), 2 had ALK-negative anaplastic large cell lymphoma (ALK- ALCL) and 3 had CD30+ mycosis fungoides (MF). Median age was 35 (range 27-71) years and the median number of prior regimens was 5 (range 1-9), including a median of 6 prior cycles of BV (range 2-19). All patients had BV-refractory disease including 16 (84%) who were non-responsive to and 3 (16%) who relapsed within 6 months of BV. Five (26%) patients with cHL received prior anti-PD-1 therapy and 4 (21%) had anti-PD-1 refractory disease. Median time from last BV and anti-PD-1 therapy to study treatment was 5.2 and 1.1 months, respectively. Eight (42%) patients had prior autologous stem cell transplant. Of response evaluable patients, the ORR and CR rate was 44% and 6% after 2 cycles and 44% and 19% after 4 cycles of therapy. Of patients who were refractory to prior BV and anti-PD-1 therapy, 1 (25%) and 1 (25%) achieved a PR and CR, respectively. ORR and CR rate was 43% and 14% for patients with cHL, 100% and 50% for patients with ALK- ALCL, and 100% and 100% for patients with MF, respectively. At completion of study, 1 patient with cHL, 1 with MF and 2 with cHL continued BV with nivolumab, BV monotherapy and nivolumab monotherapy, respectively. Median time to progression and next therapy was 4.5 (range 1.8-45.6) and 5.0 (range 1.8-45.6) months, respectively. Of the 3 patients who achieved a CR after 4 cycles of therapy, 2 (67%) continued treatment (1 with BV and nivolumab and 1 with BV monotherapy), and 1 (33%) has been on surveillance for 45.6 months with no evidence of relapse. At a median follow-up of 21.7 (range 0.5-60.4) months, 15 (79%) patients are alive with 3 in CR. Eleven (58%) and 8 (42%) patients reported no and grade 1 peripheral neuropathy (PN) at baseline, respectively. At end of treatment, 12 (63%) and 1 (5%) patients reported grade 1 and 2 PN, respectively. No patients experienced grade ≥3 PN, transaminitis, infections or infusion reactions. One (5%) patient had a 1-week dose delay due to grade 1 ALT/AST elevation. Two (11%) deaths were noted on study; one patient developed respiratory failure secondary to pneumonitis and influenza and another patient experienced cardiac arrest due to benzodiazepine withdrawal. Correlative PD-1 levels drawn at baseline and at the end of treatment did not correlate with response. Conclusions Despite the presence of BV-refractory disease, 4 cycles of BV and nivolumab is tolerable and associated with encouraging efficacy in patients with heavily treated CD30+ lymphoma. This treatment option may have increasing relevance as more patients receive BV or anti-PD-1 therapy as part of initial treatment.

Phase II Study of Lenalidomide Maintenance after Salvage Therapy for Relapsed or Refractory Peripheral T-Cell Lymphomas

Introduction Peripheral T-cell lymphomas (PTCLs) are a heterogeneous group of non-Hodgkin lymphomas. Their prognoses are still poor especially after they relapse or become refractory to the first-line treatment. Although salvage chemotherapy followed by autologous stem cell transplantation (ASCT) could be used for those relapsed or refractory patients, a substantial number of patients relapse even after ASCT. Furthermore, ASCT is not always possible because elderly or frail patients are not eligible for high-dose chemotherapy followed by ASCT. Thus, there are limited treatment option for patients who failed after ASCT or ineligible for ASCT because there is no established salvage treatment strategy and the impact of novel therapies in previous trials is unknown. Lenalidomide is widely used for the treatment of B-cell lymphomas as well as multiple myeloma, however, there are a few data about its efficacy in patients with PTCLs. Considering the mode of action is related with the immune modulatory effect on tumor microenvironment, lenalidomide might have a role in the management of relapsed or refractory PTCLs. Thus, we hypothesized that the use of lenalidomide as a maintenance therapy for patients who achieve response after salvage therapy might produce survival benefit comparable to that of ASCT after salvage therapy. Methods This is a prospective, open-labeled, single-arm, multi-center phase II study for relapsed or refractory PTCLs. The inclusion criteria are as follows: 1) Patients should have relapsed or refractory disease after at least one-line of prior chemotherapy; 2) Patients should not be eligible for ASCT; 3) Patients should have any subtypes of PTCLs including PTCL-not otherwise specified (PTCL-NOS), angioimmunoblastic T-cell lymphoma (AITL), anaplastic lymphoma kinase (ALK)-positive or -negative anaplastic large-cell lymphoma (ALCL), extranodal NK/T-cell lymphoma (ENKTL), monomorphic epitheliotropic intestinal T-cell lymphoma (MEITL), hepatosplenic T-cell lymphoma (HSTL), and mycosis fungoides (MF). When patients eligible for the study achieve complete response (CR) or partial response (PR) after four cycles of any kinds of salvage chemotherapy, they can receive lenalidomide as a maintenance therapy. One cycle is 28 days consisting of lenalidomide 25 mg (day 1 - day 21). The treatment can be repeated until progression or the occurrence of intolerable toxicities (up to 2 years). The primary end point is 1-year progression-free survival, and the target rate is 35%. Results A total of 58 patients were enrolled between February 2019 and May 2023. The median age was 62 years (range: 20 - 83 years) and male was dominant (male: 35, female: 23). Patients who failed after ASCT or could not undergo ASCT due to their health status participated in the study. Patients with AITL (n = 23) and PTCL-NOS (15) accounted for 66% of patients whereas other subtypes included ENKTL (n = 4), ALK-negative ALCL (n = 3), MEITL (n = 3), HSTL (n = 2) and MF (n = 7). Prior to the maintenance therapy with lenalidomide, their disease status was CR (n = 22, 38%) and PR (n = 36, 62%). At the median follow-up of 20.7 months (95% CI: 17.7 - 23.7 months), seven patients completed the planned treatment of 2 years, and three patients withdrew their informed consents. Disease progression was documented in 21 patients during the maintenance and the other 20 patients discontinued the treatment due to their adverse events. At the time of analysis, seven patients were maintaining their treatments. Out of 36 patients with PR before maintenance, five patients achieved CR and 13 patients showed PR. However, 18 patients showed disease progression during maintenance. On the other hand, only three patients showed disease progression among 22 patients with CR prior to lenalidomide maintenance. Thus, 1-year PFS after enrollment was 49% and the median OS was (34.1 months, 95% CI: 7.9 - 18.6 months, Figure 1). The most common hematologic toxicities were neutropenia and thrombocytopenia; thus, dose-reduction should be done in patients with grade 4 hematologic toxicity. The most frequent non-hematologic toxicities included skin rash (40%), nausea (35%), and diarrhea (20%) however, they were manageable. Conclusions The lenalidomide maintenance might be a feasible and effective treatment approach for patients with relapsed or refractory PTCLs who are ineligible for ASCT or intensive consolidation chemotherapy.

A Phase I Study Evaluating the Safety, Tolerability, Pharmacokinetics, and Preliminary Antitumor Activity of Dual CK1ε/PI3Kδ Inhibitor HZ-H08905 in Adult Patients with Relapsed and/or Refractory Hematologic Malignancies

Background: HZ-H08905 is a first-class and potent CK1ε/PI3Kδ dual inhibitor, which was previously reported (Abstract 5502, ASH 2022). Phase I study is ongoing in China, and here we present preliminary results of HZ-H08905 monotherapy in hematologic malignancies. Methods: HZ-H08905-101 is an ongoing Phase 1, first-in-human, open-label, multicenter, multiple-dose escalation and expansion study in China (CTR20213233). Primary objectives: safety/tolerability, maximum tolerated dose (MTD), and recommended phase 2 dose (RP2D) of HZ-H08905 monotherapy; secondary objectives: pharmacokinetic properties and preliminary anti-tumor activity of HZ-H08905 in patients with relapsed/refractory (R/R) non-Hodgkin lymphoma (NHL), including B-cell lymphoma (BCM) and T-cell lymphoma (TCL). HZ-H08905 was administered orally once daily in 28-day cycles until disease progression or unacceptable toxicity. The dose escalation part was initiated with a dose titration in the initial cohort (50mg once daily), followed by a 3 + 3 design (100mg, 300 or 450 mg once daily). Dose-limiting toxicity (DLT) for each cohort was evaluated in the first 28-day cycle. Dose expansion was conducted in selected doses and cohorts. Safety was assessed per CTCAE 5.0 and efficacy was measured according to IWWM-7 for WM, or IWCLL 2018 for CLL/SLL, or Lugano 2014 criteria for other NHL. Results: At the data cutoff date of 25 May 2023, 38 pts were analyzed, including 26 R/R TCL [12 AITL, 10 PTCL-NOS, 2 ALK negative ALCL, 1 NKTCL 1 EATCL] and 12 R/R BCM [5 DLBCL, 3 FL, 2 WM, 1 CLL, 1 MCL]. 1 pt received 50mg/d, 9 pts received 100mg/d, 14 pts received 200mg/d, 13 pts received 300mg/d and 1pts received 450mg/d. No DLT occurred and MTD was not reached. Pts were with a median age of 61 years (range: 38-78), median ECOG 1 (range: 0-2) and a median of 2 prior systemic therapies (range: 1-5). 35 of 38 pts (92%) experienced a treatment related adverse event (TRAE). TRAEs of ≥Grade 3 (≥5%) were neutropenia (26.3%), pneumonia (7.9%), leukopenia (5.3%), elevated aspartate aminotransferase (5.3%), elevated alanine aminotransferase (5.3%) and herpes zoster (5.3%). 10 pts (26.3%) had dose interruption, 3pts (7.9%) had dose reduction, and 1 pt (2.6%) discontinued from the study due to TRAEs. Of 35 pts available for tumor assessment (26 TCL; 12 BCM), the overall response rate (ORR) was 60% (95%CI: 42.11, 76.13), including 17% (6 pts) complete response (CR), 40% (14 pts) partial response (PR), 3% (1 pt) minor response (MR) and 20% (7 pts) stable disease (SD), contributing to an 80% (95%CI: 63.06, 91.56) disease control rate (DCR). The median time to response (mTTR) was 1.9 months (95%CI: 1.87, 2.10). The median duration of response (mDOR) and median progression free survival (mPFS) had not been reached, with 21 pts (55%) are still on HZ-H08905 treatment. HZ-H08905 exhibited excellent antitumor efficacy in several NHL subtypes, including CLL, DLBCL, FL, MCL, PTCL and WM, with ORR ranged from 50%~100% and DCR ranged from 76%~100%. Conclusions: These results demonstrated that HZ-H08905 monotherapy was well tolerated and showed promising efficacy in patients with R/R NHL. A Phase 2 R/R PTCL registration study in China is currently planned.

Retrospective Study of Allogeneic Hematopoietic Stem Cell Transplantation for Relapse or Refractory Peripheral T-Cell Lymphoma at Toranomon Hospital and Toranomon Hospital Kajigaya

[Background] Relapsed or refractory peripheral T-cell lymphoma (R/R PTCL) is known to have a poor prognosis. Although new medications have been introduced in recent years, allogeneic hematopoietic stem cell transplantation (allo-HSCT) is the only curative treatment for R/R PTCL. We review the results of allo-HSCT for PTCL at our institution. [Methods] We performed a retrospective analysis of R/R PTCL patients who underwent first allo-HSCT at our hospital from February 2011 and April 2023. The primary endpoint was OS, which was defined as the time from allo-HSCT to death from any cause or the last follow-up. The secondary endpoints included progression-free survival (PFS), relapse/progression incidence (RI) and non- relapse mortality (NRM). PFS was defined as the time from allo-HSCT to relapse/progression, death, or the last follow-up. OS and PFS were estimated by the Kaplan-Meier method and multivariate Cox proportional hazard models. The cumulative incidence of relapse and NRM were investigated with a competing risk analysis using Gray's test and multivariable Fine and Gray competing risk regression. [Results] During the study period, a total of 44 patients received first allo-HSCT for PTCL (ALK positive ALCL: 2, ALK negative ALCL: 2, AITL: 10, PTCL-NOS: 21, CTCL: 7, HSTL: 2). The median follow-up months of survivors was 51.6 (range, 2.6-141.6). The median age of patients at transplantation was 50 years (range, 17-70). Clinical stage I/II at diagnosis was 10 cases, and clinical stage III/IV was 34 cases. Prognostic Index for PTCL(PIT) was score 1 in 20 cases, score 2 in 20 cases and score 3 in 3 cases. Hematopoietic Cell Transplantation-specific Comorbidity Index (HCT-CI) ≧ 2 was 21 cases. Performance Status (PS) 0-1 was 32 cases and PS 2-4 was 12 cases. Primary induction failure (PIF) was 28 cases and relapse after first remission (REL) was 16 cases, including 5 cases of relapse after autologous stem cell transplantation. Median number of chemotherapy regimens received before allo-HSCT was 3 (range, 1-8). Clinical stage at transplantation was CR/PR in 23 patients and SD/PD in 21 patients.The majority, thirty-two had received unrelated cord blood transplantation (CBT), six did unrelated bone marrow transplantation (uBMT), and 6 did related peripheral blood stem cell transplantation (rPBSCT). Thirty-two patients received myeloablative conditioning (MAC), eighteen of which included total body irradiation (TBI) and 15 of which included busulfan (BU). Twelve patients received reduced-intensity conditioning (RIC) . Regarding the primary endpoint, the 4-year OS after allo-HSCT was 53.3%. The 4-year PFS, RI and NRM were 50.4%, 20.7% and 28.8%, respectively. The 4-year OS of CBT, uBMT and rPBSCT patients was 55.2%, 66.7% and 33.3%, respectively. The 4-year OS of REL and PIF patients was 79.1% and 39.5%, respectively (p<0.01). The 4-year OS of MAC and RIC was 49.5% and 64.3%, respectively (p=0.58). The 4-year OS of patients with TBI was superior to patients without TBI (71.1% vs 40.3%, p=0.05). The 4-year OS of CR/PR patients at transplant was superior to SD/PD patients (67.1% vs. 42.9%, p=0.05). In the univariate analysis, PS 0-1, HCT-CI 0-1, REL, CR/PR patients at transplant, patients with TBI and patients without BU were favorable prognostic factors. In the multivariable analysis, REL was associated with better OS (p=0.01, HR 0.16; 95% CI: 0.04-0.65). Except for 3 patients who died from transplant complications before engraftment, 41 patients achieved neutrophil engraftment, with a median engraftment date of 19 days (range, 11-31 days) after transplantation. Twenty-seven patients had acute GVHD (Grade I: 3, Grade II: 13, Grade III: 8, Grade IV: 3), and 11 patients had chronic GVHD. Eleven patients relapsed after transplant, and the median time from transplant to relapse was 26.3 months (range, 0.6-87.1 months). Three patients survived at the last follow up, and the median follow-up time of survivors from relapse was 430 days (range, 12-1301). [Conclusion] Our data indicated good results of allo-HSCT for R/R PTCL, and significantly better in relapse after first remission patients.

Extranodal NK/T-Cell Lymphoma Predominantly Composed of Anaplastic Cells: A Frequently Misdiagnosed and Highly Aggressive Variant.

Extranodal NK/T-cell lymphoma (ENKTL) is a non-Hodgkin lymphoma associated with the Epstein-Barr virus that primarily affects individuals in East Asia and indigenous populations in Central and South America. Morphologically, ENKTL typically consists of medium-sized cells or a combination of small and large cells. This report presents 10 cases characterized by predominantly anaplastic cells with diffuse expression of CD30, resembling anaplastic lymphoma kinase-negative anaplastic large cell lymphoma (ALK-negative ALCL) and demonstrating highly aggressive behavior. The cohort included 9 males and 1 female, ranging in age from 29 to 65 years (median age: 47y). Eight patients presented with nasal disease, while 2 had non-nasal disease. Five patients had stage I/II disease, and the remaining 5 had stage III/IV disease. Morphologically, necrosis was observed in 9 cases, angiocentric-angiodestructive growth in 3 cases, and pseudoepitheliomatous hyperplasia in 2 cases. Anaplastic cells predominated in all cases, with some displaying eccentric, horseshoe-shaped, or kidney-shaped nuclei (referred to as "Hallmark" cells). The morphology profile was monomorphic in 3 cases and polymorphic in 7 cases. Immunohistochemically, all cases tested positive for cytotoxic granule markers (TIA1 and granzymeB) and Epstein-Barr virus-encoded RNA. Cytoplasmic expression of CD3ε and CD56 was observed in 9 of 10 cases. Interestingly, most cases (7 of 8) exhibited variable expression of MuM1, ranging from 10% to 90%. All cases showed diffuse positivity for CD30 but were negative for ALK, resulting in 3 cases being initially misdiagnosed as ALK-negative ALCL. Compared with nonanaplastic cases, anaplastic cells predominant ENKTL had a significantly higher frequency of "B" symptoms, bone marrow involvement, hemophagocytic lymphohistiocytosis, and higher Ki67 proliferative index. These findings provide valuable information for pathologists, expanding their understanding of the cytologic spectrum of ENKTL. This rare variant of ENKTL, characterized by the predominance of anaplastic cells and diffuse CD30 expression, exhibits high aggressiveness and should be differentiated from ALK-negative ALCL. Awareness of this uncommon variant is crucial in preventing misdiagnosis and ensuring the timely initiation of therapy.

Phosphorylated STAT3 as a potential diagnostic and predictive biomarker in ALK- ALCL vs. CD30high PTCL, NOS.

The differential diagnosis between ALK-negative anaplastic large cell lymphoma (ALK- ALCL) and peripheral T-cell lymphoma, not otherwise specified (PTCL, NOS) with high expression of CD30 (CD30high) are essential. However, no reliable biomarker is available in daily practice except CD30. STAT3 is characteristically activated in ALCL. We aimed to investigate whether the status of STAT3 phosphorylation could help the differential diagnosis. The status of phosphorylation of STAT3 was examined using two antibodies against pSTAT3-Y705 and pSTAT3-S727 by immunohistochemistry in ALK+ ALCL (n=33), ALK- ALCL (n=22) and PTCL, NOS (n=34). Ten PTCL, NOS with diffuse CD30 expression were defined as CD30high PTCL, NOS. Flowcytometric analysis were performed to evaluate the expression of pSTAT3-Y705/S727 in PTCL, NOS (n=3). The median H-scores of pSTAT3-Y705 and S727 were 280 and 260 in ALK+ ALCL, 250 and 240 in ALK- ALCL, and 45 and 75 in CD30high subgroup, respectively. Using H score of 145 as the cutoff value, pSTAT3-S727 alone distinguished between ALK- ALCL and CD30high PTCL, NOS with a sensitivity of 100% and specificity of 83%. Additionally, pSTAT3-S727, but not pSTAT3-Y705, was also expressed by background tumor-infiltrating lymphocytes (S727TILs) in PTCL, NOS. PTCL, NOS patients with high S727TILs H score had a favorable prognosis than those with no TILs (3-year OS rate: 43% vs. 0, p=0.013) or low S727TILs (3-year OS rate: 43% vs. 0, p=0.099). Flowcytometric analysis revealed that of the three patients investigated, two had enhanced pSTAT-S727 signals in neoplastic cell populations, and all three patients were negative for pSTAT3-Y705 expression in both tumor cells and background lymphocytes. pSTAT3-Y705/S727 can be used to help distinguish ALK- ALCL from CD30high PTCL, NOS and pSTAT3-S727 expression by TILs predicts the prognosis of a subset of PTCL, NOS.

A randomized phase II trial of CHOP versus ICED and autologous stem cell transplantation in newly diagnosed T‐cell lymphoma

Purpose: Peripheral T-cell lymphomas (PTCLs) are a heterogeneous group of non-Hodgkin lymphomas, and their prognoses are still poor because of frequent relapses and the absence of optimal standard therapy. Cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) has been the backbone of frontline chemotherapy for PTCL for many years. However, it is not clear whether anthracycline-based chemotherapies such as CHOP could be standard induction therapy for PTCL. Thus, we conducted a randomized phase II study to compare the efficacy of CHOP with fractionated ifosfamide, carboplatin, etoposide, and dexamethasone (ICED). Patients and Methods: This study was a phase II, multicenter, open-label randomized trial at 21 hospitals that belonged to the Consortium for Improving Survival of Lymphoma (CISL) in Korea (CISL-1504/ROSE study). Eligible participants were patients aged 20–65 years with previously untreated histologically confirmed PTCLs based on the World Health Organization classification 2008 including PTCL-not otherwise specified (NOS), angioimmunoblastic T-cell lymphoma (AITL), ALK-negative anaplastic large-cell lymphoma (ALCL), enteropathy-associated T-cell lymphoma (EATL), and hepatosplenic T-cell lymphoma (HSTL). Patients with ALK-positive ALCL, extranodal NK/T-cell lymphoma, and mycosis fungoides/sezary syndrome were not included in the study. Patients were randomized at a 1:1 ratio to receive either CHOP or ICED every 3 weeks for 6 cycles. Upfront autologous stem cell transplantation (ASCT) was done for patients achieving complete or partial response and the primary end point was progression-free survival (PFS). Results: Between September 2015 and March 2021, 145 patients were screened, and 138 patients were enrolled. The characteristics were not different between CHOP (n = 69) and ICED (n = 66), and PTCL-NOS (n = 60) and AITL (n = 53) were dominant. The objective response rate was not different between CHOP (41/69, 59.4%) and ICED (37/66, 56.1%), and the 3-year PFS was not different between CHOP (36.7%) and ICED (33.1%, P = 0.709). Around 80% of patients who completed either CHOP or ICED followed by upfront ASCT showed 3-year overall survival (Figure 1). There was no statistically significant difference in PFS between the CHOP and ICED arms for any subgroup analyzed except AITL. CHOP was favored over ICED in AITL patients, whereas ICED was favored over CHOP in EATL/HSTL patients. ICED was associated with more anemia, neutropenia, and thrombocytopenia of all grades and grade 3 or worse, and the frequency of febrile neutropenia was higher in the ICED arm. Keywords: aggressive T-cell non-Hodgkin lymphoma, chemotherapy, stem cell transplant No conflicts of interests pertinent to the abstract.

Anaplastic large cell lymphomas with the 6p25.3 rearrangement are a heterogeneous group of tumours with a diverse molecular background

ALK-negative anaplastic large cell lymphoma (ALCL) cases with 6p25.3 rearrangement are characterized by peculiar morphological and immunohistochemical features compare to 6p25.3-negative ALK-negative ALCL cases. A subgroup of 6p25.3-positive ALK-negative ALCL cases show the t(6,7) (p25.3;q32.3) rearrangement. Aims: To analyse the differences between 6p25.3-rearranged cases with and without t(6,7) (p25.3;q32.3). Using RNA-sequencing we studied a series of 17 samples showing 6p25.3-rearrangement, identified by FISH, consisting of seven systemic and eight primary cutaneous cases including two examples of secondary skin involvement by systemic ALCL. RNA-sequencing exclusively detected a translocation involving a gene in the 6p25.3 region (either IRF4 or DUSP22) in 7/14 cases (50%). In six of these seven cases the partner proved to be the LINC-PINT region in chromosome 7, while an EXOC2::DUSP22 rearrangement was found in one case. All cases but one were primary cutaneous ALCLs. They all were CD3 positive and BCL2 negative, while most of them expressed p-STAT3. On the contrary, cases without the t(6,7) (p25.3;q32.3) were mainly systemic (71%, 5/7) against just two pcALCL. In general, they lose CD3 (50% positive) and p-STAT3 (25% positive) expression, being all of them BCL2 positive. Moreover, in 60% of them other gene fusions were found. At the transcriptional level, they were characterized by the overexpression of TCF3 (TCF7L1/E2A), DLL3, CD58 and BCL2 genes 75%(6/8) of pcALCL with 6p25.3 rearrangement featured the so-called "biphasic morphologic pattern, which was not found in cutaneous involvement from systemic ALCL. 83% (5/6) of the pcALCL cases with the "biphasic morphologic pattern" showed the t(6,7) (p25.3;q32.3) rearrangement. ALK-negative ALCL cases with 6p25.3 rearrangement are a subgroup of tumours that are heterogeneous with respect to the presence or absence of the t(6,7) (p25.3;q32.3) translocation.

ALK-negative anaplastic large cell lymphoma with JAK2 rearrangement mimicking classic Hodgkin lymphoma

ALK-negative anaplastic large cell lymphoma with JAK2 rearrangement mimicking classic Hodgkin lymphoma

Difficulties in diagnosing ALK-negative anaplastic large cell lymphoma manifesting from a skin lesion

Anaplastic large cell lymphoma is a rare form of non-Hodgkin's lymphoma that requires an early diagnosis and urgent therapy due to aggressive tumor process. Clinically, most non-Hodgkin's lymphoma present with lymphoadenopathy and В-symptoms (such as weakness, drowsiness, fatigue, subfebrile fever, profuse night sweats). However, anaplastic large cell lymphoma may present with nonspecific skin lesions with minimal or no B-symptoms. The skin lesions are heterogeneous, which may also delay verification of the diagnosis.
 We present a case of widespread anaplastic large cell lymphoma skin lesions mimicking a case of erysipelas, which progressed rapidly from a single rash on the wrist to an extensive lesion of the right breast within 1 month. Prior to verification of the diagnosis, the patient was treated for erysipelas, pyoderma, and herpes zoster with no response to therapy. Immunohistochemical examination of a skin biopsy confirmed the diagnosis of ALK-negative anaplastic large cell lymphoma. At the time of publication, the patient had completed 1 course of the CHOEP regimen, and 6 cycles of the program were planned.
 Our case demonstrates the necessity of a broad differential diagnosis of rashes torpid to the current therapy.

Composite ALK-negative anaplastic large-cell lymphoma and mantle cell lymphoma

Composite ALK-negative anaplastic large-cell lymphoma and mantle cell lymphoma

Comparison of two immunohistochemical staining protocols for ALK demonstrates non-inferiority of a 5A4 clone-based protocol versus an ALK01 clone-based protocol for the diagnosis of ALK + anaplastic large cell lymphoma

Detection of ALK rearrangement and/or expression of the ALK protein is an essential component in the evaluation of many neoplasms. Variability has been reported in the ability of different antibody clones to detect ALK expression. The ALK01 clone is commonly used to detect ALK expression in ALK-positive anaplastic large cell lymphoma (ALK + ALCL). However, this clone has been shown to lack sensitivity when used for solid tumors. The aim of this study was to determine if our high-sensitivity 5A4-based immunohistochemistry protocol is non-inferior to our ALK01-based protocol for the detection of ALK expression in ALK + ALCL. To compare the two protocols, we stained tissue microarrays of 126 hematolymphoid neoplasms and an additional 21 primary cutaneous ALK-negative anaplastic large cell lymphomas with both protocols. All 28 ALK + ALCL samples that were positive for the ALK01 antibody were also positive for the 5A4 clone. Three cases on the tissue microarray that were negative with the ALK01 antibody were clearly positive with the 5A4 antibody. We subsequently stained whole tissue sections of these three cases with the ALK01 antibody and found that these three cases were indeed positive with the ALK01 protocol, suggesting that the absence of staining on the tissue microarray samples was due to a combination of sampling error as well as a dimmer signal with the ALK01 protocol. Our study demonstrates that our 5A4-based protocol is non-inferior to the ALK01 antibody for the diagnosis of ALK-positive anaplastic large cell lymphoma, thus allowing our laboratory to discontinue the use of the ALK01-based protocol.

DUSP22 rearrangement is associated with a distinctive immunophenotype but not outcome in patients with systemic ALK-negative anaplastic large cell lymphoma.

DUSP22 rearrangement (R) has been associated with a favorable outcome in systemic ALK-negative anaplastic large cell lymphoma (ALCL). However, a recent study found that patients with DUSP22-R ALK-negative ALCL have a poorer prognosis than was reported initially. In this study, we compared the clinicopathological features and outcomes of patients with ALKnegative ALCL with DUSP22-R (n=22) versus those without DUSP22-R (DUSP22-NR; n=59). Patients with DUSP22-R ALCL were younger than those with DUSP22-NR neoplasms (P=0.049). DUSP22-R ALK-negative ALCL cases were more often positive for CD15, CD8, and less frequently expressed pSTAT3Tyr705, PD-L1, granzyme B and EMA (all P<0.05). TP63 rearrangement (TP63-R) was detected in three of the 66 (5%) ALK-negative ALCL cases tested and none of these cases carried the DUSP22-R. Overall survival of patients with DUSP22-R ALCL was similar to that of the patients with DUSP22-NR neoplasms regardless of International Prognostic Index score, stage, age, or stem cell transplantation status (all P>0.05), but was significantly shorter than that of the patients with ALK-positive ALCL (median overall survival 53 months vs. undefined, P=0.005). Five-year overall survival rates were 40% for patients with DUSP22-R ALCL versus 82% for patients with ALK-positive ALCL. We conclude that DUSP22-R neoplasms represent a distinctive subset of ALK-negative ALCL. However, in this cohort DUSP22-R was not associated with a better clinical outcome. Therefore, we suggest that current treatment guidelines for this subset of ALK-negative ALCL patients should not be modified at present.

ALK-negative anaplastic large cell lymphoma with DUSP22 rearrangement has distinctive disease characteristics with better progression-free survival: a LYSA study.

ALK-negative anaplastic large cell lymphoma (ALCL) comprises subgroups harboring rearrangements of DUSP22 (DUSP22- R) or TP63 (TP63-R). Two studies reported 90% and 40% 5-year overall survival (OS) rates in 21 and 12 DUSP22-R/TP63- not rearranged (NR) patients, respectively, making the prognostic impact of DUSP22-R unclear. Here, 104 newly diagnosed ALK-negative ALCL patients (including 37 from first-line clinical trials) from the LYSA TENOMIC database were analyzed by break-apart fluorescence in situ hybridization assays for DUSP22-R and TP63-R. There were 47/104 (45%) DUSP22-R and 2/93 (2%) TP63-R cases, including one DUSP22-R/TP63-R case. DUSP22-R tumors more frequently showed CD3 expression (62% vs. 35%, P=0.01), and less commonly a cytotoxic phenotype (27% vs. 82%; P<0.001). At diagnosis, DUSP22- R ALCL patients more frequently had bone involvement (32% vs. 13%, P=0.03). The patient with DUSP22-R/TP63-R ALCL had a rapidly fatal outcome. After a median follow-up of 4.9 years, 5-year progression-free survival (PFS) and OS rates of 84 patients without TP63-R treated with curative-intent anthracycline-based chemotherapy were 41% and 53%, respectively. According to DUSP22 status, 5-year PFS was 57% for 39 DUSP22-R versus 26% for 45 triple-negative (DUSP22-NR/TP63-NR/ALK-negative) patients (P=0.001). The corresponding 5-year OS rates were 65% and 41%, respectively (P=0.07). In multivariate analysis, performance status and DUSP22 status significantly affected PFS, and distinguished four risk groups, with 4-year PFS and OS ranging from 17% to 73% and 21% to 77%, respectively. Performance status but not DUSP22 status influenced OS. The use of brentuximab vedotin in relapsed/refractory patients improved OS independently of DUSP22 status. Our findings support the biological and clinical distinctiveness of DUSP22- R ALK-negative ALCL. Its relevance to outcome in patients receiving frontline brentuximab vedotin remains to be determined.