Intrathecal IgM synthesis as a diagnostic marker in patients with suspected CNS lymphoma.

For CNS lymphomas (CNSL), there is a high need for minimally invasive and easily obtainable diagnostic markers. Intrathecal IgM synthesis can easily be determined in routine CSF diagnostics. The aim of this study was to systematically investigate the diagnostic potential of intrathecal IgM synthesis in primary and secondary CNSL (PCNSL and SCNSL). In this retrospective study, patients with a biopsy-proven diagnosis of PCNSL or SCNSL were compared with patients with other neurological diseases in whom CNSL was initially the primary radiological differential diagnosis based on MRI. Sensitivity and specificity of intrathecal IgM synthesis were calculated using receiver operating characteristic curves. Seventy patients with CNSL were included (49 PCNSL and 21 SCNSL) and compared to 70 control patients. The sensitivity and specificity for the diagnosis of CNSL were 49% and 87%, respectively, for the entire patient population and 66% and 91% after selection for cases with tumor access to the CSF system and isolated intrathecal IgM synthesis. In cases with MRI-based radiological suspicion of CNSL, intrathecal IgM synthesis has good specificity but limited sensitivity. Because of its low-threshold availability, analysis of intrathecal IgM synthesis has the potential to lead to higher diagnostic accuracy, especially in resource-limited settings, and deserves further study.

Primary central nervous system marginal zone lymphoma.

Marginal zone lymphoma (MZL) is the most common indolent lymphoma primarily arising in the central nervous system (CNS). To date, 207 cases of primary CNS MZL (PCNSMZL) were published, mostly as single case reports or small case series. It most commonly presents as extra-axial dural-based masses, more frequently in middle-aged women, displaying an insidious onset, with a long history of symptoms preceding the diagnosis. PCNSMZL can be radiographically mistaken for meningioma. PCNSMZL consists of CD20+ , CD3- small B lymphocytes with varying degrees of plasmacytic differentiation and low proliferation index. Trisomy 3, but not MALT1 or IgH translocation, is a common genetic abnormality. Other recurrent genetic abnormalities involve TNFAIP3 and NOTCH2. Ethiopathogenesis was poorly investigated. Due to its rarity, standard of care remains to be defined; it exhibits an excellent prognosis after varied treatments, such as surgery, radiotherapy, chemotherapy or their combinations. Nevertheless, each treatment should be considered after an accurate analysis of overtreatment risk. Short follow-up is a major limitation in reported PCNSMZL cases, which restrains our knowledge on long-term results and iatrogenic sequels. This review was focussed on presentation, differential diagnoses, pathological findings, treatment options and clinical outcomes of PCNSMZL; recommendations for best clinical practice are provided.

Clinical outcomes of etoposide and cytarabine as consolidation in elderly patients with primary CNS lymphoma.

BACKGROUND: A consolidation strategy has not been established for transplant-ineligible elderly patients with primary central nervous system lymphoma (PCNSL). In this study, we aimed to retrospectively evaluate the clinical outcomes of etoposide and cytarabine (EA) as consolidation chemotherapy for transplant-ineligible patients with PCNSL following high-dose methotrexate (MTX)-based induction chemotherapy. MATERIALS AND METHODS: Between 2015 and 2021, newly diagnosed transplant-ineligible patients with PCNSL with diffuse large B-cell lymphoma were consecutively enrolled. All enrolled patients were over 60 years old and received EA consolidation after achieving a complete or partial response following induction chemotherapy. RESULTS: Of the 85 patients who achieved a complete or partial response to MTX-based induction chemotherapy, 51 received EA consolidation chemotherapy. Among the 25 (49.0%, 25/51) patients in partial remission before EA consolidation, 56% (n = 14) achieved complete remission after EA consolidation. The median overall survival and progression-free survival were 43 and 13 months, respectively. Hematological toxicities were most common, and all patients experienced grade 4 neutropenia and thrombocytopenia. Forty-eight patients experienced febrile neutropenia during consolidation chemotherapy, and 4 patients died owing to treatment-related complications. CONCLUSION: EA consolidation chemotherapy for transplant-ineligible, elderly patients with PCNSL improved response rates but showed a high relapse rate and short progression-free survival. The incidences of treatment-related mortality caused by hematologic toxicities and severe infections were very high, even after dose modification. Therefore, the use of EA consolidation should be reconsidered in elderly patients with PCNSL.

Treatment of secondary CNS lymphoma using CD19-targeted chimeric antigen receptor (CAR) T cells.

BACKGROUND: Aggressive B cell lymphoma with secondary central nervous system (CNS) involvement (SCNSL) carries a dismal prognosis. Chimeric antigen receptor (CAR) T cells (CAR-T) targeting CD19 have revolutionized the treatment for B cell lymphomas; however, only single cases with CNS manifestations successfully treated with CD19 CAR-T have been reported. METHODS: We prospectively enrolled 4 patients with SCNSL into our study to assess clinical responses and monitor T cell immunity. RESULTS: Two of four SNCSL patients responded to the CD19-targeted CAR-T. Only one patient showed a substantial expansion of peripheral (PB) CAR-T cells with an almost 100-fold increase within the first week after CAR-T. The same patient also showed marked neurotoxicity and progression of the SNCSL despite continuous surface expression of CD19 on the lymphoma cells and an accumulation of CD4+ central memory-type CAR-T cells in the CNS. Our studies indicate that the local production of chemokine IP-10, possibly through its receptor CXCR3 expressed on our patient's CAR-T, could potentially have mediated the local accumulation of functionally suboptimal anti-tumor T cells. CONCLUSIONS: Our results demonstrate expansion and homing of CAR-T cells into the CNS in SNCSL patients. Local production of chemokines such as IP-10 may support CNS infiltration by CAR-T cells but also carry the potential of amplifying local toxicity. Future studies investigating numbers, phenotype, and function of CAR-T in the different body compartments of SNSCL patients receiving CAR-T will help to improve local delivery of "fit" and highly tumor-reactive CAR-T with low off-target reactivity into the CNS.

Relevance of different prognostic scores in primary CNS lymphoma in the era of intensified treatment regimens: A retrospective, multicenter analysis of 174 patients.

OBJECTIVES: Treatment intensification (including consolidative high-dose chemotherapy with autologous stem cell transplantation [HDT-ASCT]) significantly improved outcome in primary central nervous system lymphoma (PCNSL) patients. METHODS: We conducted a multicenter, retrospective analysis of newly diagnosed PCNSL patients, treated with intensified treatment regimens. The following scores were evaluated in terms of overall survival (OS) and progression-free survival (PFS): Memorial Sloan-Kettering Cancer Center (MSKCC), International Extranodal Lymphoma Study Group (IELSG), and three-factor (3F) prognostic score. Further, all scores were comparatively investigated for model quality and concordance. RESULTS: Altogether, 174 PCNSL patients were included. One hundred and five patients (60.3%) underwent HDT-ASCT. Two-year OS and 2-year PFS for the entire population were 73.3% and 48.5%, respectively. The MSKCC (p = .003) and 3F score (p < .001), but not the IELSG score (p = .06), had the discriminatory power to identify different risk groups for OS. In regard to concordance, the 3F score (C-index [0.71]) outperformed both the MSKCC (C-index [0.64]) and IELSG (C-index [0.53]) score. Moreover, the superiority of the 3F score was shown for PFS, successfully stratifying patients in three risk groups, which also resulted in the highest C-index (0.66). CONCLUSION: The comparative analysis of established PCNSL risk scores affirm the clinical utility of the 3F score stratifying the widest prognostic spectrum among PCNSL patients treated with intensified treatment approaches.

Ocular motor and vestibular dysfunction in central nervous system lymphoma.

BACKGROUND AND PURPOSE: Diagnosis of lymphoma involving the central nervous system (CNS) is challenging. This study aimed to explore the abnormal vestibular and ocular motor findings in CNS lymphoma. METHODS: A retrospective search of the medical records identified 30 patients with CNS lymphoma presenting ocular motor and vestibular abnormalities from four neurology clinics of university hospitals in South Korea (22 men, age range 14-81 years, mean 60.6 ± 15.2). The demographic and clinical features and the results of laboratory, radiological and pathological evaluation were analyzed. RESULTS: Patients presented with diplopia (13/30, 43%), vestibular symptoms (15/30, 50%) or both (2/30, 7%). In 15 patients with diplopia, abnormal ocular motor findings included ocular motor nerve palsy (n = 10, 67%), internuclear ophthalmoplegia (n = 2, 13%), external ophthalmoplegia (n = 2, 13%) and exophoria (n = 1, 7%). The vestibular abnormalities were isolated in 14 (82%) of 17 patients with vestibular symptoms and included combined unilateral peripheral and central vestibulopathy in three from lesions involving the vestibular nuclei. CNS lymphoma involved the brainstem (53%), cerebellum (33%), leptomeninges (30%), deep gray nuclei (23%) or cranial nerves (17%). Two patients showed the "double-panda" sign by involving the midbrain. CONCLUSIONS: This study expands the clinical and radiological spectra of CNS lymphoma. Neuro-ophthalmological and neuro-otological evaluation may guide the early diagnosis of CNS lymphoma.

Top advances of the year: Neuro-oncology.

Management of brain tumors has been challenging given the limited therapeutic options and disabling morbidities associated with central nervous system (CNS) dysfunction. This review focuses on recent developments in the field, with an emphasis on clinical management. The growing clinical trials landscape reflects advanced insights into cancer immunology and genomics and the need to address molecular and clinical heterogeneity. Recent phase 3 trials investigating anti-PD-1 immunotherapies, particularly nivolumab, have failed to demonstrate improved survival in glioblastoma, underscoring the need to better understand the complexity of CNS immunologic surveillance. Conversely, targeted therapies have accounted for several US Food and Drug Administration approvals extended to brain tumors, particularly therapies directed to BRAF V600E mutations and TRAK fusions, underscoring a need to routinely screen patients for these rare molecular abnormalities. In primary CNS lymphoma, attention has turned to long-term outcomes of consolidation therapies, and recent studies have highlighted the excellent disease control afforded by high-dose chemotherapy and stem cell transplantation. Meningiomas remain a focus of investigations, with preliminary promising results observed with octreotide combined with mTOR inhibition, and immunotherapy with single-agent pembrolizumab. Finally, proton radiotherapy has emerged as a novel alternative for leptomeningeal metastases from solid tumors, which can now be treated more safely with craniospinal irradiation and monitored by the enumeration of circulating tumor cells in the cerebrospinal fluid as a biomarker. Taken together, these incremental advances have improved outcomes in select brain tumor patient populations, whereas ongoing clinical trials hold the promise of meaningful advances and breakthroughs for larger proportions of patients with brain tumors.

Combining MYD88 L265P mutation detection and clonality determination on CSF cellular and cell-free DNA improves diagnosis of primary CNS lymphoma.

Diagnosis of primary central nervous system lymphoma (PCNSL) is challenging, and although brain biopsy remains the gold standard, cerebrospinal fluid (CSF) constitutes a less invasive source of lymphomatous biomarkers. In a retrospective cohort of 54 PCNSL cases tested at diagnosis or relapse, we evaluated the contribution of immunoglobulin heavy chain (IGH) gene clonality and MYD88 L265P detection on both CSF cell pellets and supernatants, in comparison with cytology, flow cytometry, interleukin (IL)-10 and IL-6 quantification. Clonality assessment included a new assay to detect partial IGH-DJ rearrangements. Clonal IGH rearrangements and/or MYD88 L265P mutation were detected in 27 (50%) cell pellets and 24 (44%) supernatant cell-free (cf) DNA. Combining analyses on both compartments, 36 (66%) cases had at least one detectable molecular marker, present only in cfDNA for 9 (16%) of them. While cytology and flow cytometry were positive in only 7 (13.0%) and 9 (17.3%) cases respectively, high IL-10 levels were observed in 36 (66.7%) cases. Overall, taking into account molecular and cytokine results, 46/54 (85%) cases had at least one lymphomatous biomarker detectable in the CSF. These results show that this combination of biomarkers evaluated on both cell pellet and supernatant CSF fractions improves significantly the biological diagnosis of PCNSL.

Safety and efficacy of induction immunochemotherapy with rituximab, methotrexate, ifosfamide, and vincristine (R-MIV) in patients with primary CNS lymphoma including recent COVID-19 pandemic experience.

Clinical data on primary central nervous system (CNS) lymphoma (PCNSL) patients is mostly generated from prospective studies, and many frail real-world patients are not included. Recently,the diagnosis and treatment of PCNSL patients was confounded by the COVID-19 pandemic. In particular, treatment with high-dose cytarabine was linked to increased risk of pneumonia and virus persistence. We report on outcome of the induction regimen R-MIV (rituximab, methotrexate, ifosfamide, and vincristine) involving intensive administration of high-dose methotrexate (3.5 g/m2 ) with ifosfamide, every 2 weeks and rituximab once per week for six doses. The median age and performance status (PS) for 64 patients was 58 years and 2 (PS 3; 22%) respectively. The overall response rate by magnetic resonance imaging/computed tomography (MRI/CT) was 73% (n = 46/63), with an additional 17.5% (n = 11/63) patients without measurable disease at baseline. Grade 3-4 haematological toxicity was low for R-MIV (neutropenia: 25% and thrombocytopenia: 1%). Three patients (4.7%) died from treatment-related toxicity. Co-existence of SARS-CoV-2 infection with cytomegalovirus reactivation and the varicella-zoster virus in two patients was fatal. Fifty patients (78%) were eligible for consolidation. Median progression-free and overall survival were not reached (median follow-up: 44 months). In conclusion, the R-MIV regimen is feasible in routine practice, effective and safe, even during the COVID-19 pandemic.

Genomic Profiling Reveals Differences in Primary Central Nervous System Lymphoma and Large B-Cell Lymphoma, With Subtyping Suggesting Sensitivity to BTK Inhibition.

BACKGROUND: B-cell primary central nervous system (CNS) lymphoma (PCL) is diffuse large B-cell lymphoma (DLBCL) confined to the CNS. Less than 50% of patients with PCL achieve complete remission with current therapies. We describe the findings from comprehensive genomic profiling (CGP) of a cohort of 69 patients with PCL, 36 cases of secondary CNS lymphoma (SCL), and 969 cases of DLBCL to highlight their differences and characterize the PCL cohort. In addition, we highlight the differences in frequency of germinal center B-cell like (GCB) and non-GCB subtypes and molecular subtypes, particularly MCD and EZH subtypes, between PCL and DLBCL. MATERIALS AND METHODS: Sixty-nine cases of B-cell PCL, 36 cases of secondary CNS lymphoma (SCL), and 969 cases of DLBCL were evaluated by CGP of 405 genes via DNAseq and 265 genes via RNAseq for fusions (FoundationOne Heme). Tumor mutational burden (TMB) was calculated from 1.23 Mb of sequenced DNA. RESULTS: Genomic alterations with significant differences between PCL and DLBCL included MYD88, ETV6, PIM1, PRDM1, CXCR4, TP53, and CREBBP, while only MYD88 was significantly different between SCL and DLBCL. PCL cases were significantly enriched for the MCD molecular subtypes, which have an excellent response to BTKi. We report a patient with a durable complete response to BTKi consistent with their genomic profile. EBV status, CD274 amplification, and TMB status suggest that 38% of PCL patients may benefit from ICPI; however further study is warranted. CONCLUSION: CGP of PCLs reveals biomarkers, genomic alterations, and molecular classifications predictive of BTKi efficacy and potential ICPI efficacy. Given the limitations of standard of care for PCL, CGP is critical to identify potential therapeutic approaches for patients in this rare form of lymphoma.

Integrated genetic analyses of immunodeficiency-associated Epstein-Barr virus- (EBV) positive primary CNS lymphomas.

Immunodeficiency-associated primary CNS lymphoma (PCNSL) represents a distinct clinicopathological entity, which is typically Epstein-Barr virus-positive (EBV+) and carries an inferior prognosis. Genetic alterations that characterize EBV-related CNS lymphomagenesis remain unclear precluding molecular classification and targeted therapies. In this study, a comprehensive genetic analysis of 22 EBV+ PCNSL, therefore, integrated clinical and pathological information with exome and RNA sequencing (RNASeq) data. EBV+ PCNSL with germline controls carried a median of 55 protein-coding single nucleotide variants (SNVs; range 24-217) and 2 insertions/deletions (range 0-22). Genetic landscape was largely shaped by aberrant somatic hypermutation with a median of 41.01% (range 31.79-53.49%) of SNVs mapping to its target motifs. Tumors lacked established SNVs (MYD88, CD79B, PIM1) and copy number variants (CDKN2A, HLA loss) driving EBV- PCNSL. Instead, EBV+ PCNSL were characterized by SOCS1 mutations (26%), predicted to disinhibit JAK/STAT signaling, and mutually exclusive gain-of-function NOTCH pathway SNVs (26%). Copy number gains were enriched on 11q23.3, a locus directly targeted for chromosomal aberrations by EBV, that includes SIK3 known to protect from cytotoxic T-cell responses. Losses covered 5q31.2 (STING), critical for sensing viral DNA, and 17q11 (NF1). Unsupervised clustering of RNASeq data revealed two distinct transcriptional groups, that shared strong expression of CD70 and IL1R2, previously linked to tolerogenic tumor microenvironments. Correspondingly, deconvolution of bulk RNASeq data revealed elevated M2-macrophage, T-regulatory cell, mast cell and monocyte fractions in EBV+ PCNSL. In addition to novel insights into the pathobiology of EBV+ PCNSL, the data provide the rationale for the exploration of targeted therapies including JAK-, NOTCH- and CD70-directed approaches.

Management of primary and secondary CNS lymphoma.

Central nervous system (CNS) lymphoma has traditionally had very poor outcomes however advances in management have seen dramatic improvements and long-term survival of patients. In primary CNS lymphoma there are now randomised trial data to inform practice, however secondary CNS lymphoma has a lack of randomised trial data and CNS prophylaxis remains a contentious area. We describe treatment strategies in these aggressive disorders. Dynamic assessment of patient fitness and frailty is key throughout treatment alongside delivery of CNS-bioavailable therapy and enrolment in clinical trials. Intensive high-dose methotrexate-containing induction followed by autologous stem cell transplantation is preferred for patients who are fit. Less intensive chemoimmunotherapy, whole brain radiotherapy and novel therapies may be reserved for patients unfit or chemoresistant. It is essential to better define patients at increased risk of CNS relapse, as well as effective prophylactic strategies to prevent it. Future prospective studies incorporating novel agents are key.

Central nervous system lymphomas-Assessment and treatment and prevention of central nervous system relapse.

In this review focused on lymphoma and the central nervous system (CNS), we summarize recent developments in the management of primary (PCNSL) and secondary CNS lymphoma (SCNSL), treatment of CNS lymphoma in the older population, the neuroradiological assessment of CNS lymphoma and finally highlight the ongoing debate on optimal CNS prophylaxis. The section on PCNSL focuses on the different approaches available for frontline treatment in Europe and the United States and discusses consolidation strategies. We then highlight available strategies to treat PCNSL in the elderly population, an area of unmet need. New therapies aiming at minimizing toxicity and prioritizing quality of life are emerging for these patients. Secondary CNS lymphoma, especially in the relapsed/refractory setting is another area of unmet need, and the efficacy of CAR-T cell therapy is being explored. We provide an overview of the imaging challenges in the neuroradiological assessment of CNS lymphoma. Finally, the section on CNS prophylaxis summarizes recent findings from large retrospective studies challenging the efficacy of present approaches to prophylaxis in higher-risk patients with lymphoma.

Autologous hematopoietic cell transplantation versus whole-brain radiotherapy consolidation in primary central nervous system lymphoma: A systematic review and meta-analysis.

The management of newly diagnosed primary central nervous system lymphoma (PCNSL) includes administration of high-dose methotrexate based regimens followed by consolidation therapy to minimize the risk of relapse. However, the best consolidation strategy (autologous hematopoietic cell transplant [auto-HCT] vs. whole-brain radiotherapy [WBRT]) is controversial. Hence, we performed a systematic review and meta-analysis of all randomized controlled trials that compared auto-HCT versus WBRT consolidation for patients with PCNSL after first-line treatment.The primary outcome was overall survival (OS), while the secondary outcomes included progression-free survival (PFS), response rates (overall response rate [ORR] and complete remission [CR]), relapse rate, treatment-related mortality (TRM), and neuropsychological adverse events. We performed a pooled analysis of the single-arm studies that incorporated auto-HCT or WBRT consolidation and evaluated neurocognitive outcomes. Only two studies met the inclusion criteria (n = 240). There was no significant difference in OS (HR = 1.50; 95% CI = 0.95-2.36), PFS (HR = 0.99; 95% CI = 0.44-2.22), ORR (RR = 1.48; 95% CI = 0.90-2.44), CR rate (RR = 1.21; 95% CI = 0.90-1.63), relapse rate (RR = 0.46; 95% CI = 0.05-4.28), and TRM (RR = 5.67; 95% CI = 1.01-31.91). The neuropsychological tests to assess neurocognitive domains were different and inconsistently reported in the two studies and therefore we were unable to perform a meta-analysis but provide a descriptive assessment. Both the studies showed a significant decline in the attention/executive function (based on the trail making test A and trail making test B) in those receiving WBRT compared to auto-HCT. We found 9 single-arm phase II studies that reported data on outcomes associated with either auto-HCT (5 studies) or WBRT (4 studies) consolidation. Of these, two studies (n = 43) reported data on neurocognitive decline following auto-HCT consolidation. Pooled proportion of patients with neurocognitive decline in these studies was 6% (95% CI, 0%-17%) for those receiving auto-HCT and there was no heterogeneity between studies (I2  = 0%). Three studies (n = 122) reported data on neurocognitive decline following WBRT consolidation. Pooled proportion of patients with neurocognitive decline in these studies was 43% (95% CI, 11%-78%) for those receiving WBRT and there was high heterogeneity between studies (I2  = 94%). There was significant heterogeneity between subgroups (p = 0.035). The outcomes were not significantly different in patients with PCNSL receiving auto-HCT or WBRT consolidation therapies, however, there is a higher degree of neurocognitive decline associated with WBRT compared to auto-HCT consolidation. The decision to choose a consolidation strategy needs to be individualized based on age, frailty, and co-morbidities.

CAR T-cell therapy in large B cell lymphoma.

CD19-targeted chimeric antigen receptor (CAR) T-cells have revolutionized the treatment of lymphoid malignancies, including large B cell lymphoma (LBCL). Following seminal early phase multicenter clinical trials published between 2017 and 2020, three CD19-CAR T-cell products received FDA and EMA approval designations in lymphoma in the third-line setting, paving the way for follow-up studies in the second-line. Meanwhile, investigations into the applications of CAR T-cell therapy have further broadened to treating high-risk patients even prior to completion of first-line conventional chemo-immunotherapy. Furthermore, as early trials excluded patients with central nervous system involvement with lymphoma, several studies have recently shown promising efficacy of CD19-CAR T-cells in primary and secondary CNS lymphoma. Here we provide a detailed overview on clinical data supporting the use of CAR T-cells in patients with LBCL.

A retrospective study of 222 patients with newly diagnosed primary central nervous system lymphoma-Outcomes indicative for improved survival overtime.

Primary central nervous system lymphoma (PCNSL) is a rare disease with an incidence of 0.4/per 100,000 person-years. As there is a limited number of prospective randomized trials in PCNSL, large retrospective studies on this rare disease may yield information that might prove useful for the future design of randomized clinical trials. We retrospectively analyzed the data of 222 newly diagnosed PCNSL patients treated in five referral centers in Israel between 2001 and 2020. During this period, combination therapy became the treatment of choice, rituximab has been added to the induction therapy, and consolidation with irradiation was largely laid off and was mostly replaced by high-dose chemotherapy with or without autologous stem cell transplantation (HDC-ASCT). Patients older than 60 comprised 67.5% of the study population. First-line treatment included high-dose methotrexate (HD-MTX) in 94% of patients with a median MTX dose of 3.5 g/m2 (range 1.14-6 g/m2 ) and a median cycle number of 5 (range 1-16). Rituximab was given to 136 patients (61%) and consolidation treatment to 124 patients (58%). Patients treated after 2012 received significantly more treatment with HD-MTX and rituximab, more consolidation treatments, and autologous stem cell transplantation. The overall response rate was 85% and the complete response (CR)/unconfirmed CR rate was 62.1%. After a median follow-up of 24 months, the median progression-free survival (PFS) and overall survival (OS) were 21.9 and 43.5 months respectively with a significant improvement since 2012 (PFS: 12.5 vs. 34.2 p = 0.006 and OS: 19.9 vs. 77.3 p = 0.0003). A multivariate analysis found that the most important factors related to OS were obtaining a CR followed by rituximab treatment and Eastern Cooperative Oncology Group performance status. The observed improvement in outcomes may be due to multiple components such as an intention to treat all patients regardless of age with HD-MTX-based combination chemotherapy, treatment in dedicated centers, and more aggressive consolidation with the introduction of HDC-ASCT.

Performance status, comorbidities, and cycles of methotrexate exert the greatest influence on outcomes of primary and secondary CNS lymphomas: the Lexington experience.

Primary central nervous system lymphoma (PCNSL) occurs primarily in older patients and has a worse prognosis than other extranodal lymphomas. Contemporary treatment is based on high-dose methotrexate (HD-MTX), which crosses the blood-brain barrier. Secondary CNS lymphoma (SCNSL) can occur concomitantly with systemic lymphoma or later at relapse and generally has a dismal outcome. We reviewed disease characteristics and outcomes of 103 patients (44 PCNSL and 59 SCNSL) treated at our center between 2015 and 2020. Median ages at diagnosis were 64 and 62 years, respectively. In both groups, diffuse large B cell lymphoma (DLBCL) was the major histologic type; in SCNSL, other types were also seen. SCNSL, in contrast with PCNSL, manifested with smaller tumors or cerebrospinal fluid positivity. For SCNSL the mean interval to brain involvement was 18 months (0-138). The overall survival had a trend to worse in SCNSL; median survival 11 months versus 61 months in PCNSL (p = 0.089). Progression-free survival was similar in both groups. A significant proportion of SCNSL patients with poor performance status could not obtain CNS-directed treatments. The strongest predictor of poor outcome was ECOG performance status 2 + at diagnosis for both groups. Charlson comorbidity index was predictive only for the PCNSL cohort. Tumor size was not prognostic for survival. The number of HD-MTX cycles correlated with survival, whereas the regimen itself and average cumulative dose of methotrexate did not play a role. Our study is in line with the recent literature and confirms ongoing challenges. We discuss how the outcomes of CNS lymphomas can be improved.

Systemic relapses of primary CNS lymphomas (PCNSL): a LOC network study.

Primary central nervous system lymphomas (PCNSLs) classically remain confined within the CNS throughout their evolution for unknown reasons. Our objective was to analyse the rare extracerebral relapses of PCNSL in a nationwide population-based study. We retrospectively selected PCNSL patients who experienced extracerebral relapse during their follow-up from the French LOC database. Of the 1968 PCNSL included in the database from 2011, 30 (1.5%, median age 71 years, median KPS 70) presented an extracerebral relapse, either pure (n = 20) or mixed (both extracerebral and in the CNS) (n = 10), with a histological confirmation in 20 cases. The median delay between initial diagnosis and systemic relapse was 15.5 months [2-121 months]. We found visceral (n = 23, 77%), including testis in 5 (28%) men and breast in 3 (27%) women, lymph node (n = 12, 40%), and peripheral nervous system (PNS) (n = 7, 23%) involvement. Twenty-seven patients were treated with chemotherapy, either with only systemic targets (n = 7) or mixed systemic and CNS targets (n = 20), 4 were consolidated by HCT-ASCT. After systemic relapse, the median progression-free survival and overall survival (OS) were 7 and 12 months, respectively. KPS > 70 and pure systemic relapses were significantly associated with higher OS. Extracerebral PCNSL relapses are rare, mainly extranodal, and frequently involve the testis, breast, and PNS. The prognosis was worse in mixed relapses. Early relapses raise the question of misdiagnosed occult extracerebral lymphoma at diagnostic workup that should systematically include a PET-CT. Paired tumour analysis at diagnosis/relapse would provide a better understanding of the underlying molecular mechanisms.

A unique case of a fulminant clonal CD8-positive T-cell lymphoproliferative disorder with CNS involvement.

BACKGROUND: This is a unique case that describes the presentation, investigations, and disease trajectory of a fatal, clonal CD8-positive T-cell lymphoproliferative disorder in an otherwise healthy and immunocompetent patient with Epstein-Barr virus seronegative status. Central nervous system involving T-cell lymphoproliferative disorders are rare and typically encountered in the setting of immunocompromise. These disorders are often associated with aggressive cytomorphological features and characteristic magnetic resonance imaging patterns, which were not seen in this case. CASE PRESENTATION: Here we describe a case of a 65 year-old male presenting with neuropsychiatric symptoms, truncal ataxia, and falls who's bone marrow, cerebrospinal fluid, and brain biopsy were consistent with a clonal CD8-positive T-cell lymphoproliferative disorder that did not meet existing World Health Organization criteria for classification as T-cell lymphoma. The patient was treated with intrathecal methotrexate resulting in transient improvement of his symptoms followed by disease progression and death related to aspiration. CONCLUSIONS: This case highlights the importance of urgent and comprehensive work-up in patients with clinical features suggestive of lymphoma with central nervous system involvement, despite atypical imaging features and lack of cytomorphological features satisfying current World Health Organization classification criteria.

Evaluation of progression-free survival as a surrogate end point in primary CNS lymphoma: a systematic review and meta-analysis.

Purpose: To evaluate progression-free survival (PFS) as early surrogate endpoints for overall survival (OS) in primary CNS lymphoma (PCNSL). Methods: PubMed, Embase and Cochrane Central Library were searched up to 7 June 2022. Trial-level analyses were performed by weighted linear regression of logarithmic hazard ratios for PFS and OS. Treatment arm-level analyses were performed between PFS rates and 3- or 5-year OS rates. Results: 1471 PCNSL patients in nine randomized control trials were included. PFS was associated with OS (r = 0.750; 95% CI: 0.228-0.937). Strong linear correlations existed between 1-, 2- and 3-year PFS and 3-year OS (r = 0.896-0.928), moderate or weak correlations existed between 3- to 6-month PFS and 3-year OS, 3-month to 5-year PFS and 5-year OS. Conclusion: Short-term PFS can validly substitute for long-term OS in PCNSL.