Primary Central Nervous System Lymphoma Patients Research Articles

Identification of Genomic Biomarkers of Disease Progression and Survival in Primary CNS Lymphoma.

The determination of the genetic subtypes of primary CNS lymphoma (PCNSL) and their relationship to differential chemo-immunotherapeutic response has not been established. There is a particular need for genomic biomarkers that identify patients with newly-diagnosed PCNSL at high risk of early progression and death. We applied targeted next-generation sequencing for detection of recurrent single nucleotide variants, copy number alterations and zygosity abnormalities in diagnostic specimens from 78 PCNSL patients treated with a standard methotrexate-based regimen, to identify prognostically significant molecular subgroups. All patients received induction immunochemotherapy and 44 proceeded to dose-intensive consolidation. Genomic aberrations at four loci were associated with 91% of lymphoma progression events and all 15 deaths: (1) chromosome 6p copy-neutral loss of heterozygosity (CN-LOH) or focal homozygous deletion (HD) at 6p21.3, and mutations of tumor suppressor genes (2) BTG1, (3) ETV6 and (4) TP53. Cox regression multivariate analysis demonstrated a high risk of progression in patients with aberrations at these loci. Genomic aberrations at these loci were also associated with significantly shorter survival. Lower expression of HLA-DR was associated with 6p CN-LOH/6p21.3 HD and inferior prognosis. These genomic aberrations identify a high-risk molecular subgroup that may inform risk stratification in PCNSL. Further elucidation of the mechanisms of therapeutic resistance associated with the high-risk genetic phenotype is requisite to facilitate precision medicine and progress in therapy.

Assessing the intracranial metabolic score as a novel prognostic tool in primary CNS lymphoma with end of induction-chemotherapy 18F-FDG PET/CT and PET/MR.

The metabolic response of primary central nervous system lymphoma (PCNSL) patients has yet to be evaluated. This study aimed to assess the prognostic value of a novel scoring scale, the intracranial metabolic score (IMS), in PCNSL patients receiving end-of-therapy 18F-FDG PET/CT (EOT-PCT) and PET/MR (EOT-PMR). The IMS was determined based on the metabolism of normal intracranial structures, including gray matter, white matter, and cerebrospinal fluid. The EOT-PCT cohort was evaluated using the IMS and commonly used Deauville score (DS). Another cohort of patients who underwent the EOT-PMR was used to validate the accuracy of the IMS. In total, 83 patients were included in the study (38 in PET/CT cohort, and 45 in PET/MR cohort). The area under the curve (AUC) values of the IMS for predicting PFS and OS were superior to those of the DS. When patients in the PET/CT cohort were stratified into five groups (respectively labeled IMS 1-5), three groups (IMS1-2, IMS 3-4, and IMS 5), or two groups (IMS1-3 and IMS4-5; IMS 1-4 and IMS 5), a higher IMS score was significantly correlated with poorer PFS and OS (p < 0.001). Similar results were observed for PFS in the PET/MR cohort (p < 0.001). The IMS and DS scale were found to be independent prognostic indicators for PFS and OS in the PET/CT cohort, and the IMS was identified as the sole independent prognostic indicator for PFS in the PET/MR cohort. The IMS as a novel and effective prognostic tool for PCNSL patients, showing superior predictive value for patients' outcomes compared to the DS when assessed with EOT-PET scans.

CTIM-35. PD-1 BLOCKADE WITH CAMRELIZUMAB IN RELAPSED/REFRACTORY PRIMARY CENTRAL NERVOUS SYSTEM LYMPHOMA

Abstract Primary central nervous system lymphoma (PCNSL) are rare extranodal large B-cell lymphomas. There are no standard-of-care treatment options for patients with relapsed and refractory PCNSL and the overall prognosis is poor. We conducted a phase 2 clinical trial to evaluate the efficacy and adverse events of PD-1 antibody camrelizumab in relapsed/refractory PCNSL. Enrolled patients received camrelizumab 200mg intravenously every 2 weeks. The primary endpoint was overall response rate (ORR). Here we present results of 20 relapsed PCNSL patients who treated with camrelizumab. Among them,12 were male and 8 were female. The median age was 57 years (range 25-67 years). Fourteen patients were available to evaluate efficacy. After camrelizumab treatment, 4 got complete response (CR), 3 got partial response (PR), 1 got stable disease, and 6 got progressed disease (PD). The ORR was 50%. The median progression-free survival (PFS) was 19.3 weeks (95% CI, 3.1-35.5). 24 week PFS rate was 40%. For the 7 patients who got CR/PR, got a long sustained response, with a median PFS of 93.6 weeks (range 17-211.6+ weeks). One patient developed pseudoprogression 2 months after initiation of treatment. By the last follow-up, 18 patients discontinued treatment (10 PD, 4 complete treatment, 3 withdrawal of informed consent, 1 lost follow-up). Eleven patient got PD. Nine patients received chemotherapy and 5 received radiotherapy after PD. PD-L1 expression, microsatellite stability and mutation burden of the tumors were detected in 9 patients, and all the three factors were not correlated with efficacy. The main drug-related adverse reaction was cutaneous capillary hyperplasia. None of the patients dropped out of the study due to adverse reactions. Our data suggest that camrelizumab is active in relapsed/refractory PCNSL and support further investigation of PD-1 blockade in PCNSL.

CTNI-33. EARLY COMPLETE RESPONSE MIGHT NOT BE AN INDICATOR OF LONGER PROGRESSION-FREE SURVIVAL IN NEWLY-DIAGNOSED PRIMARY CENTRAL NERVOUS SYSTEM LYMPHOMA WITH A COMPLETE RESPONSE BY MTX-BASED INDUCTION THERAPY

Abstract Primary central nervous system lymphoma (PCNSL) is an extra-nodal non-Hodgkin lymphoma solely arising from the central nervous system including eyes. While 70% of patients with newly-diagnosed PCNSL achieve a complete response (CR) after R-MPV, the current standard of care MTX-based induction therapy, recurrence yet frequently occurs (~50%) and clinical factors related to failure are not well defined. Early complete response is associated with lower recurrence rate in various cancers. In this study, we conducted a retrospective, single-institution study to investigate whether early complete response was associated with recurrence in PCNSL. Newly-diagnosed PCNSL patients treated with R-MPV at the authors’ institution between 2011 and 2022 were identified, and progression-free survival (PFS), overall survival (OS) were analyzed along with number of chemotherapy cycles required to achieve a CR or CR unconfirmed (CRu). In total of 92 patients treated with R-MPV identified, 68 (75%) patients achieved a CR or CRu. Among patients who achieved CR or CRu, a median total of seven (1-8) R-MPV cycles were delivered. The median cycle required to achieve CR or CRu was five (1-8). Consolidation whole brain radiation therapy (WBRT) was given to 29 younger patients (median age: 63), while 39 older patients (median age: 74) were treated without WBRT. The number of chemotherapy cycles required to achieve CR or CRu was not associated with PFS or OS in all ages. However, requiring six or more chemotherapy cycles to achieve CR or CRu was associated with longer PFS (p=0.046) in patients treated without WBRT. These data suggest that early complete response might not be indicative of superior survival outcome in newly-diagnosed PCNSL treated without consolidation WBRT. Persisting enhancing lesions during chemotherapy could lead to treatment intensification through delivering greater number of chemotherapy cycles, which might have conferred longer PFS in these patients.

CTNI-38. SINGLE-CENTER COMPARATIVE ANALYSIS ABOUT OUTCOMES OF MULTI-AGENTS CHEMOTHERAPY FOR PRIMARY CENTRAL NERVOUS SYSTEM LYMPHOMA; R-MPV SHOWED A FAVOR RESULT

Abstract BACKGROUND Primary central nervous system lymphoma (PCNSL) is a malignant tumor in the brain, spinal cord, and eyes. Radiotherapy may cause delayed leukoencephalopathy so that the first-line treatment is methotrexate (MTX)-based multi-agent chemotherapy. We had used the Bonn protocol based on MTX and cytarabine, but since 2020, we have adopted the R-MPV protocol. This study analyzes the outcomes of patients treated initially at our institution. METHODS AND RESULTS We reviewed 57 out of 88 newly diagnosed PCNSL patients treated with chemotherapy alone between December 2005 and January 2023. Initial treatments included the Bonn protocol in 25 patients (12 with rituximab, forming R-Bonn) and R-MPV in 26 patients. High-dose chemotherapy with peripheral blood stem cell transplantation (PBSCT) was given as consolidation in 4 Bonn and 9 R-MPV patients. The Bonn protocol was completed by 20 patients (80%) with a complete response (CR) in 19 (76%). The R-MPV protocol was completed by 23 patients (88%) with CR in 22 (85%). Post-treatment outcomes were compared using survival analysis. Median progression-free survival (mPFS) had not been reached in the R-MPV group and was significantly better than 33.1 months in the Bonn protocol and 58.6 months in the R-Bonn protocol (log-rank test; p=0.0296, 0.0036). Overall survival (OS) did not show significant differences. PBSCT’s impact on outcomes suggested improvement in PFS and OS after R-MPV, but this was not statistically significant. DISCUSSION We examined the efficacy of different chemotherapy regimens for PCNSL at our institution. The R-MPV protocol showed superior completion rates, response rates, and treatment efficacy. Consolidation with PBSCT may improve outcomes, though further investigation with more cases and longer observation is necessary.

MRI-based Radiomics Virtual Biopsy for BCL6 in Primary Central Nervous System Lymphoma

AimTo establish machine learning model based on radiomic signature for predicting B-cell lymphoma 6 (BCL-6) rearrangement in primary central nervous system lymphoma (PCNSL). Materials and MethodsRetrospective study on 102 PCNSL patients (31 with BCL-6 rearrangement positive, 71 with BCL-6 rearrangement negative) were randomly divided into the training and validation set at a ratio of 7:3. Radiomics models based on contrast-enhanced T1-weighted imaging (CE-T1WI) and fluid-attenuated inversion recovery (FLAIR) in different regions including VOItumor core and VOIperitumoral edema. Radiomics features were extracted and selected using LASSO regression, and radiomics score (rad-score) were calculated using the weighted coefficients. Four machine learning models (logistic regression, random forest, support vector machine, K-nearest neighbors) were developed and evaluated based rad-score. The optimal radiomics model was integrated into the clinical or radiological factors to construct a predictive model through logistic regression analysis. A nomogram was constructed based on independent significant features for individualized prediction. ResultsAll rad-scores based on CE-T1WI and FLAIR sequences were significantly associated with BCL6 rearrangement (p<0.05) in univariate regression analysis. LR machine learning model performed best with AUCs of 0.935 (training) and 0.923 (validation). Rad-scores from CE-T1WI tumor core and peritumoral edema were independent significant predictors. ConclusionRadiomics signature based on CE-T1WI and FLAIR sequences have significant value in distinguishing BCL6 rearrangement. The CE-T1WI radiomics model based on VOItumor core and VOIperitumoral edema are robust markers for identifying BCL6 rearrangement.

Distinguishing clinical and imaging characteristics of primary central nervous system lymphoma from high-grade glioma and metastatic brain tumors.

The purpose of this retrospective analysis was to evaluate the clinical presentations, radiological characteristics, patient outcomes, and therapeutic approaches among individuals diagnosed with primary central nervous system lymphoma (PCNSL), high-grade glioma (HGG), and metastatic brain tumors (METS). We assembled a cohort of brain tumor patients from two medical centers, with two oncologists independently reviewing their clinical profiles. A retrospective examination of 87 PCNSL, 87 HGG, and 71 METS cases was performed to assess the aforementioned parameters. Notable variations were identified in the incidence of epileptic seizures and cognitive impairments between PCNSL and METS patients. Cerebral hemisphere involvement was predominantly observed in HGG and METS cases. PCNSL cases exhibited a higher likelihood of multiple lesions, whereas HGG showed a greater tendency for recurrence. The median survival times were established at 24.3months for PCNSL, 44.5months for HGG, and 27.1months for METS patients. In PCNSL cases, the number of lesions was identified as a significant predictor of mortality (P = 0.008). Our findings highlight the importance of clinical and imaging features in diagnosing PCNSL, which may present distinct features compared to HGG and METS.

Primary central nervous system lymphoma: a series report and literature review

ObjectiveThis study aims to analyze the clinical features, Radiological findings and diagnostic characteristics (tissue biopsy, flow cytometry and cerebrospinal fluid cytology) of primary central nervous system lymphoma (PCNSL). To improve the diagnosis of the disease.MethodsA total of 19 patients with primary central nervous system lymphoma admitted to the Second Hospital of Hebei Medical University from 2014 to 2023 were selected. The clinical data of the patients were retrospectively analyzed. Combined with the relevant literature, the clinical characteristics of PCNSL patients were analyzed to assist the diagnosis.ResultMost of the patients were middle-aged and elderly patients (65 years old), and the main clinical manifestations showed no obvious specificity, including headache, dizziness and limb weakness. Radiological findings showed that common site of currence were located in the brain parenchyma. The PCNSL subtype of 19 patients was all diffuse large B cell subtype by cytology, flow cytometry or histopathology. Six cases were diagnosed by biopsy pathology and 11 cases were diagnosed by flow cytometry of cerebrospinal fluid. In all patients diagnosed with PCNSL by clinical cytology (CSF cytology and flow cytometry), abnormal cells were found on CSF examination.ConclusionThe pathological type of primary central nervous system lymphoma was diffuse large B-cell subtype, with diverse clinical manifestations and multiple. Both tissue directed biopsy and flow cytometry could effectively assist clinical diagnosis. Early and timely diagnosis and intervention are of great significance for delaying the disease process and reducing the economic burden of patients and families.

Clinicopathological analysis of primary central nervous system lymphoma in patients with or without HIV infection

The clinicopathological features of HIV-related primary central nervous system lymphoma (PCNSL) and immunocompetent primary central nervous system lymphoma (IC-PCNSL) were found to be distinct. Thirty-seven patients with HIV-related PCNSL and thirty patients with IC-PCNSL were included in our study. Hematoxylin & eosin (HE) staining, immunohistochemical detection using CD10, MUM1, CD20, Bcl-2, Bcl-6, p53, C-MYC, Ki67, methyltransferase like factor 3 (METTL3) antibodies and Epstein–Barr encoding region (EBER) in situ hybridization were performed. All of the patients were classified as the diffuse large B-cell lymphoma (DLBCL) histological type. Patients with HIV-related PCNSL were younger and more likely to be male, with elevated lactate dehydrogenase (LDH) and low sugar content in cerebrospinal fluid (CSF) compared to patients with IC-PCNSL.The positive rates of METTL3, Bcl-2, p53 and EBER were significantly higher in HIV-related PCNSL patients than in IC-PCNSL patients. Furthermore, we also found that the expression of METTL3 was lower in germinal centre B-cell (GCB)-like DLBCL (n = 7) than in non-GCB like DLBCL (n = 30) in HIV-related PCNSL (P = 0.030); however, in IC-PCNSL patients, the expression of METTL3 was not significantly different between GCB-like DLBCL and non-GCB-like DLBCL (P = 0.670). Although the manifestations are similar in PCNSL patients with and without HIV, HIV-related PCNSL differs from IC-PCNSL in terms of pathological characteristics including METTL3, Bcl-2, p53 and EBER. We therefore suggest that the pathogenesis of HIV-related PCNSL and IC-PCNSL may differ according to host immune status.

MRI-Based Machine Learning for Prediction of Clinical Outcomes in Primary Central Nervous System Lymphoma.

A portion of individuals diagnosed with primary central nervous system lymphomas (PCNSL) may experience early relapse or refractory (R/R) disease following treatment. This research explored the potential of MRI-based radiomics in forecasting R/R cases in PCNSL. Forty-six patients with pathologically confirmed PCNSL diagnosed between January 2008 and December 2020 were included in this study. Only patients who underwent pretreatment brain MRIs and complete postoperative follow-up MRIs were included. Pretreatment contrast-enhanced T1WI, T2WI, and T2 FLAIR imaging were analyzed. A total of 107 radiomic features, including 14 shape-based, 18 first-order statistical, and 75 texture features, were extracted from each sequence. Predictive models were then built using five different machine learning algorithms to predict R/R in PCNSL. Of the included 46 PCNSL patients, 20 (20/46, 43.5%) patients were found to have R/R. In the R/R group, the median scores in predictive models such as support vector machine, k-nearest neighbors, linear discriminant analysis, naïve Bayes, and decision trees were significantly higher, while the apparent diffusion coefficient values were notably lower compared to those without R/R (p < 0.05). The support vector machine model exhibited the highest performance, achieving an overall prediction accuracy of 83%, a precision rate of 80%, and an AUC of 0.78. Additionally, when analyzing tumor progression, patients with elevated support vector machine and naïve Bayes scores demonstrated a significantly reduced progression-free survival (p < 0.05). These findings suggest that preoperative MRI-based radiomics may provide critical insights for treatment strategies in PCNSL.

Impact of Postoperative Chemotherapy on Survival in Patients with Primary Central Nervous System Lymphoma: A Study Based on the SEER Database.

Aims/Background We aimed to investigate the impact of postoperative chemotherapy (POCT) on survival in patients with primary central nervous system lymphoma (PCNSL) using data from the Surveillance, Epidemiology, and End Results (SEER) database. Methods This study included 786 PCNSL patients, of which 605 received chemotherapy after surgery, and 181 did not. Data from the SEER registry database (2007-2020) were used to analyze PCNSL. Baseline information, including age, sex, race, marital status, primary tumour site, histological type, summary stage, surgical procedures, chemotherapy, and radiotherapy, was analyzed. Propensity Score Matching (PSM) (1:1) was employed to balance the effects of confounding variables between the two groups. Subsequently, Cox regression and bidirectional stepwise regression were used to identify independent prognostic factors. Kaplan-Meier (K-M) survival curves were constructed to assess the impact of POCT on patient prognosis. Additionally, two cases of PCNSL with typical magnetic resonance imaging appearances were presented. Results Multivariate Cox regression results revealed that age older than 60 years (hazard ratio [HR] = 1.786; 95% confidence interval [CI]: 1.272-2.509; p = 0.001) and absence of POCT (HR = 2.841; 95% CI: 2.159-3.738; p < 0.001) were independent prognostic risk factors, while primary tumour locations in the meninges (HR = 0.136; 95% CI: 0.032-0.569; p = 0.006) and other nervous system regions (HR = 0.552; 95% CI: 0.326-0.936; p = 0.027), as well as histological morphologies such as diffuse large B-cell lymphoma (HR = 0.233; 95% CI: 0.128-0.425; p < 0.001) and non-Hodgkin lymphoma (HR = 0.559; 95% CI: 0.356-0.876; p = 0.011), were associated with favourable patient outcomes. K-M curves demonstrated that the group undergoing POCT had a significantly more favourable prognosis compared to the non-POCT group, before (HR = 0.454; 95% CI: 0.343-0.600; p < 0.0001) or after PSM (HR = 0.580; 95% CI: 0.431-0.780; p < 0.0001). For patients with PCNSL, those with tumours located in the infratentorial region (HR = 0.231; 95% CI: 0.078-0.682; p = 0.046), supratentorial region (HR = 0.250; 95% CI: 0.163-0.383; p < 0.0001), overlapping brain regions (HR = 0.201; 95% CI: 0.056-0.727; p = 0.0058), and those who underwent biopsy (HR = 0.740; 95% CI: 0.463-1.182; p = 0.003), subtotal resection (STR) (HR = 0.490; 95% CI: 0.265-0.906; p = 0.0064), or gross total resection (GTR) (HR = 0.613; 95% CI: 0.292-1.287; p = 0.0003) had better prognoses in the postoperative chemotherapy group compared to the non-chemotherapy group. Conclusion POCT significantly improves the prognosis of PCNSL patients and identifies the characteristics of the benefiting population. This information aids clinical practitioners in designing personalized treatment plans for individuals and advancing precise treatment.

Radiomic prediction for durable response to high-dose methotrexate-based chemotherapy in primary central nervous system lymphoma.

The rarity of primary central nervous system lymphoma (PCNSL) and treatment heterogeneity contributes to a lack of prognostic models for evaluating posttreatment remission. This study aimed to develop and validate radiomic-based models to predict the durable response (DR) to high-dose methotrexate (HD-MTX)-based chemotherapy in PCNSL patients. A total of 159 patients pathologically diagnosed with PCNSL between 2011 and 2021 across two institutions were enrolled. According to the NCCN guidelines, the DR was defined as the remission lasting ≥1 year after receiving HD-MTX-based chemotherapy. For each patient, a total of 1218 radiomic features were extracted from prebiopsy T1 contrast-enhanced MR images. Multiple machine-learning algorithms were utilized for feature selection and classification to build a radiomic signature. The radiomic-clinical integrated models were developed using the random forest method. Model performance was externally validated to verify its clinical utility. A total of 105 PCNSL patients were enrolled after excluding 54 cases with ineligibility. The training and validation cohorts comprised 76 and 29 individuals, respectively. Among them, 65 patients achieved DR. The radiomic signature, consisting of 8 selected features, demonstrated strong predictive performance, with area under the curves of 0.994 in training cohort and 0.913 in validation cohort. This signature was independently associated with the DR in both cohorts. Both the radiomic signature and integrated models significantly outperformed the clinical models in two cohorts. Decision curve analysis underscored the clinical utility of the established models. This radiomic signature and integrated models have the potential to accurately predict the DR to HD-MTX-based chemotherapy in PCNSL patients, providing valuable therapeutic insights.

Combination of rituximab and methotrexate followed by rituximab and cytarabine in elderly patients with primary central nervous system lymphoma.

The optimal treatment strategy for newly diagnosed primary central nervous system lymphoma (PCNSL) has yet to be established, especially in the elderly. In the current study, we conducted a phase II study to evaluate the efficacy and safety of rituximab plus high-dose MTX followed by rituximab plus cytarabine in patients aged ≥60 years newly diagnosed with PCNSL. Patients received an induction treatment of high-dose methotrexate plus rituximab followed by two cycles of a consolidation treatment of cytarabine plus rituximab. The primary end-point was a 2-year progression-free survival (PFS) rate. A total of 35 patients were recruited, and their median age was 73 (range: 60-81). After induction treatment, the complete and partial responses (PRs) were 56% and 20% respectively. Twenty-six patients proceeded to the consolidation treatment; the complete and PRs were 59% and 9% respectively. After a median follow-up duration of 36.0 months, the 2-year PFS rate was 58.7%. Treatment was generally well-tolerated as only three patients were withdrawn from the study due to toxicity, and no treatment-related mortality was reported. The 2-year overall survival rate was 77.9%. The current study may suggest the feasibility of administering high-dose MTX plus cytarabine in PCNSL patients aged ≥60 years and the potential role of additive rituximab.

The Prognostic Significance of Pontine-White Matter Score in Primary Central Nervous System Lymphoma Patients.

Limited data exist on the significance of PET imaging and quantitative PET parameters in primary central nervous system (CNS) lymphoma due to its relative rarity. This study was conducted to investigate the prognostic value of a novel internal standardization indicator, the pontine-white matter (PW) score, in primary CNS lymphoma patients undergoing post-treatment 18F-FDG PET/CT and PET/MR imaging. From January 2014 to December 2022, eligible patients with primary CNS lymphoma who underwent post-treatment PET imaging were enrolled. Using the FDG uptake of the pons and white matter as an internal reference, the PW score was graded based on the metabolism of the post-therapeutic lesion for each patient, and its associations with patients' prognosis were investigated. In total, 41 patients with post-treatment PET/CT and 49 patients with post-treatment PET/MR imaging were enrolled. ROC curve analysis indicated that the PW score possessed robust discriminative ability in distinguishing patients with worse outcomes. Furthermore, a higher PW score was significantly correlated with and identified as an independent prognostic indicator for, worse prognosis in both the PET/CT and PET/MR cohorts. The study demonstrated that the PW score was an effective prognostic indicator for identifying post-treatment primary CNS lymphoma patients with worse outcomes.

Outcomes and relapse patterns in primary central nervous system lymphoma: Longitudinal analysis of 559 patients diagnosed from 1983 to 2020.

Contemporary outcomes and relapse patterns in primary CNS lymphoma (PCNSL) are lacking. We analyzed factors associated with relapse in a large cohort with extensive follow-up. T1-post-contrast-enhancing disease was characterized in immunocompetent PCNSL (diffuse large B-cell) patients from 1983 to 2020. Patients were stratified by response to induction and consolidation (complete/unconfirmed [CR/CRu], partial, stable, progression [POD]). Refractory was POD during (or relapse ≤3 months of) induction. Initial relapse site was categorized as local (involving/adjacent to baseline), distant intraparenchymal, leptomeningeal, or other. Progression-free (PFS) and overall survival (OS) were assessed with proportional hazards. Cumulative incidence with competing risks was used to assess local relapse. Median follow-up was 7.4 years (N = 559). Most (321, 57%) were recursive partitioning analysis class 2 (age ≥50, Karnosfky Performance Status [KPS] ≥70). Most had supratentorial (420, 81%), multifocal (274, 53%), bilateral (224, 43%), and deep structure involvement (314, 56%). Nearly all received methotrexate-based induction (532, 95%). There was no difference in PFS or OS from consolidation based on initial response to induction (CR/CRu vs PR) in patients who ultimately achieved a CR/CRu to consolidation. PFS at 1-, 5 years for 351 patients with CR/CRu to consolidation was 80% (95% confidence interval [95% CI]: 76%-84%) and 46% (95% CI: 41%-53%), respectively; 1-year cumulative incidence of local versus nonlocal relapse was 1.8% versus 15%, respectively. For 97 refractory patients, 1-year cumulative incidence of local versus nonlocal relapse was 57% versus 42%, respectively. Deep structure involvement (HR 1.89, 95% CI: 1.10%-3.27%) was associated with local relapse in refractory patients. We report the first comprehensive relapse patterns in a large PCNSL cohort. While relapses post-CR to consolidation are typically distant and unpredictable, refractory patients had a relatively high incidence of local relapse. These findings can help optimize multimodality therapy for this highest-risk population.

Exploring the diagnostic potential of cerebrospinal fluid (CSF) IL-10:IL-6 ratio in patients with primary central nervous system lymphoma (PCNSL).

e14041 Background: Primary Central Nervous System Lymphomas (PCNSL) present significant diagnostic challenges due to their aggressive nature. Current diagnostic methods include neuroimaging, CSF cytology, FDG-PET scans, and biopsies. Building upon the success of the IL-10:IL-6 ratio as a diagnostic biomarker in intraocular lymphoma, this study investigates its potential in PCNSL diagnosis. CSF IL-10:IL-6 ratio emerges as a promising, easily accessible biomarker for early PCNSL detection. Methods: Fifteen histopathologically confirmed PCNSL patients were compared with fifteen CNS inflammatory condition patients and ten patients with other CNS malignancies. Detailed clinical assessments were conducted, and IL-10:IL-6 levels were measured in serum and CSF using Flow cytometry. Results: The CSF IL-10:IL-6 Ratio was elevated (&gt; 1) compared to serum levels in PCNSL patients in contrast to other control groups. The mean age ± SD of PCNSL patients was 55.47 ± 17.29, with a male-to-female ratio of 8:7. The mean (SD) for CSF IL-10:IL-6 ratio in PCNSL was 3.35 (3.88), while the mean (SD) for serum IL-10:IL-6 ratio was 0.438 (1.54). The statistical analysis revealed a significant difference (P = 0.0058 &lt; 0.05). Conversely, comparing the CSF IL-10:IL-6 ratio with serum levels in controls with CNS inflammatory conditions and CNS malignancies showed no statistical significance (P &gt; 0.05). Conclusions: Elevated CSF IL-10 and CSF IL-10/IL-6 ratios suggest their potential as early diagnostic markers for large B cell PCNSL. The IL-10:IL-6 ratio holds promise as a novel, easily accessible biomarker in readily available body fluids for PCNSL diagnosis.

Clinical Features and Prognostic of Patients with Primary Central Nervous System Lymphoma

To explore the clinical features and prognosis of patients with primary central nervous system lymphoma（PCNSL）. A retrospective analysis was performed on the relationship between clinical features, treatment regimen and prognosis in 46 newly diagnosed patients with primary central nervous system lymphoma who were diagnosed and treated in The Second Hospital of Lanzhou University from January 2015 to September 2022. Fisher's exact probability method was used to analyze the differences in clinical data of different subgroups. Kaplan-Meier survival curve was used to analyze the overall survival rate and progression-free survival rate of patients with different treatments, and the factors influencing survival were analyzed. Among 46 patients with PCNSL, which pathological type were diffuse large B-cell lymphoma（DLBCL）. There were 26(56.5%) cases of male and 20(43.5%) of female, with a median age of 54(17-71) years. In Hans subtypes, 14 cases (30.4%) of GCB subtype, 32 cases (69.6%) of non-GCB subtype. 32 cases (69.6%) of Ki-67≥80%. Among 36 patients who completed at least 2 cycles of treatment with follow-up data, the efficacy evaluation was as follows: overall response rate(ORR) was 63.9%, complete response(CR) rate was 47.2%, 17 cases of CR, 6 cases of PR. The 1-year progression-free survival rate and 1-year overall survival rate was 73.6% and 84.9%, respectively. The 2-year progression-free survival rate and 2-year overall survival rate was 52.2% and 68.9%, respectively. The ORR and CR rate of 17 patients treated with RMT regimen was 76.5% and 52.9% (9 cases CR and 4 cases PR), respectively. Univariate analysis of 3 groups of patients treated with RMT regimen, RM-BTKi regimen, and RM-TT regimen as first-line treament showed that deep brain infiltration was associated with adverse PFS(P =0.032), and treatment regimen was associated with adverse OS in PCNSL patients（P =0.025）. Different treatment modalities were independent prognosis predictors for OS, the deep brain infiltration of PCNSL is a poor predictive factor for PFS. Patients with relapse/refractory (R/R) PCNSL have a longer overall survival time because to the novel medication BTKi. They have strong toleration and therapeutic potential as a first-line therapy for high-risk patients.

Orelabrutinib, rituximab, temozolomide and high-dose methotrexate (RMOT) in newly diagnosed primary central nervous system lymphoma (PCNSL): A retrospective analysis on efficacy and safety.

e19041 Background: PCNSL is a rare, aggressive malignant tumor and has a poor prognosis. HD-MTX-based regimen is the first-line treatment of PCNSL. Orelabrutinib is a novel, potent, highly selective BTK inhibitor with a high CSF concentration. Recent evidence has shown the efficacy and safety of orelabrutinib in PCNSL. Therefore, we conducted a retrospective study of clinical outcomes in newly diagnosed PCNSL patients (pts) treated with RMOT regimen in routine clinical care. Methods: This retrospective cohort included the pts (aged 18-80 years) with newly diagnosed PCNSL who received 6 cycles of RMOT regimen (rituximab 375 mg/m2 iv day 1; MTX 3.5 g/m2 iv day 1; temozolomide 150 mg/m2 po day 1 to day 5; orelabrutinib 150 mg qd po; 4 weeks per cycle) as the first-line induction therapy between Nov. 2021 and Aug. 2023. All the pts were proposed to receive orelabrutinib monotherapy as maintenance after RMOT therapy. We recommend to receive autologous stem cell transplantation (ASCT) or whole brain radiation therapy (WBRT) as consolidation after RMOT therapy. Efficacy was assessed by MRI/PET per the International PCNSL Collaborative Group (IPCG) criteria. The primary endpoint was overall response rate (ORR); secondary endpoints were CR rate, progression-free survival (PFS), overall survival (OS), and safety. Results: Ten pts (6 males) with PCNSL were included, with a median age of 61 years (range, 45-77). All pts had a histologically confirmed diffuse large B-cell lymphoma. 4 pts (40%) underwent WBRT after induction therapy. As of the cut-off date (December 31, 2023), the median follow-up time was 9.7 (range, 4.8-25.7) month. All pts were evaluated for the treatment response. An interim evaluation after 4 cycles was available for 10 pts, showing complete remission (CR) rate of 80% (8/10), partial response (PR) rate of 20% (2/10), giving an ORR of 100.0% (10/10, Table). At data cutoff, the best ORR was 100.0% (10/10), with all pts achieved CR. Of 10 responders, 9 had an ongoing response, and 1 died of covid-19 infection. Median PFS/OS was not reached (NR) (95% CI NR-NR). The most common AEs were anemia, other include white blood cell or platelet count decreased. Reported AEs were generally manageable and resolved soon after supportive treatment. Only 1 (10%) pts experienced ≥grade 3 AEs—acute kidney injury. No treatment-related death occurred. Conclusions: This retrospective data suggested that RMOT had an encouraging anti-tumor activity in newly diagnosed PCNSL pts, with a toleratable safety profile. This orelabrutinib-containing regimens may provide a potential treatment strategy for pts with PCNSL. [Table: see text]

Whole Exome Sequencing Reveals Gene Mutation Characteristics of Primary Central Nervous System Lymphoma

To investigate gene mutation characteristics of primary central nervous system lymphoma (PCNSL) through whole exome sequencing (WES) to 18 patients with PCNSL. Tumor tissues from 18 patients with diffuse large B-cell lymphoma who were diagnosed with PCNSL in Department of Hematology, Lanzhou University Second Hospital from September 2018 to December 2020 and had normal immune function, no history of HIV or immunosuppressant therapy were collected. High-throughput-based WES was performed on the tumor tissues, with an average sequencing depth of >100×. After data processing and bioinformatics analysis of sequencing results, the mutation maps and mutation characteristics of 18 PCNSL patients were obtained. Obvious somatic mutations were detected in all 18 patients. The median number of somatic mutations was 321. Missense mutations were most prominent (accounting for about 90%), and the mutation type was dominated by C>T (50.2%), reflecting the age-related mutation pattern. Among the top 15 frequently mutated genes, PSD3, DUSP5, MAGEB16, TELO2, FMO2, TRMT13, AOC1, PIGZ, SVEP1, IP6K3, and TIAM1 were the driver genes. The enrichment results of driver gene pathways showed that RTK-RAS, Wnt, NOTCH, Hippo and Cell-Cycle pathways were significantly enriched. The tumor mutation burden was between 3.558 48/Mb and 8.780 89/Mb, and the average was 4.953 32/Mb, which was significantly higher than other cancer research cohorts in the TCGA database. PCNSL occurs somatic missense mutations frequently, mainly point mutations, and the mutation type is mainly C>T. The driver genes are mainly involved in RTK-RAS, Wnt, NOTCH and Hippo pathways, indicating that the above pathways may be related to the pathogenesis of PCNSL. PCNSL has a significantly high tumor mutation burden, which may explain the efficacy of PD-1 inhibitors in PCNSL.

Primary brain lymphoma and glioblastoma: evaluation of DCE T1 and DSC T2 MRI perfusion findings.

The accurate differentiation of primary central nervous system lymphoma (PCNSL) from glioblastoma multiforme (GBM) is clinically crucial due to the different treatment strategies between them. To define magnetic resonance imaging (MRI) perfusion findings in PCNSL to make a safe distinction from GBM with dynamic contrast-enhanced (DCE) T1 and DSC T2 MRI perfusion findings. This retrospective analysis included 19 patients with histopathologically diagnosed PCNSL and 21 individuals with GBM. DCE T1 vascular permeability perfusion values including K-trans, Ve, Kep, IAUGC, and DSC T2 perfusion values including cerebral blood volume (CBV) and cerebral blood flow (CBF) in axial sections from the pathological lesion and contralateral normal brain parenchyma were measured quantitatively using region of interest analysis. The study observed no statistically significant difference between patients with PCNSL (T/B cell) and GBM in the median values of DCE T1 perfusion ratios (P > 0.05). Nevertheless, the DSC T2 perfusion ratios showed a substantial distinction between the two groups. In contrast to patients with PCNSL (1.185 vs. 1.224, respectively), those with GBM had higher median levels of r-CBV and r-CBF (2.898 vs. 2.467, respectively; P 0.01). A cutoff value of ≤1.473 for r-CBV (Lesion/N) and ≤1.6005 for r-CBF (Lesion/N) was found to estimate the positivity of PCNSL. DSC T2 MRI perfusion values showed lower r-CBV and r-CBF values in PCNSL patients compared to GBM patients. According to the findings, r-CBV and r-CBF are the most accurate MRI perfusion parameters for distinguishing between PCSNL and GBM.