CAR T-cell therapy induces a high rate of prolonged remission in relapsed primary CNS lymphoma: Real-life results of the LOC network

The prognosis of relapsed primary central nervous system lymphoma (PCNSL) remains dismal. CAR T-cells are a major contributor to systemic lymphomas, but their use in PCNSL is limited. From the LOC network database, we retrospectively selected PCNSL who had leukapheresis for CAR-T cells from the third line of treatment, and, as controls, PCNSL treated with any treatment, at least in the third line and considered not eligible for ASCT. Twenty-seven patients (median age: 68, median of three previous lines, including ASCT in 14/27) had leukapheresis, of whom 25 received CAR T-cells (tisa-cel: N = 16, axi-cel: N = 9) between 2020 and 2023. All but one received a bridging therapy. The median follow-up after leukapheresis was 20.8 months. The best response after CAR-T cells was complete response in 16 patients (64%). One-year progression-free survival from leukapheresis was 43% with a plateau afterward. One-year relapse-free survival was 79% for patients in complete or partial response at CAR T-cell infusion. The median overall survival was 21.2 months. Twenty-three patients experienced a cytokine release syndrome and 17/25 patients (68%) a neurotoxicity (five grade ≥3). The efficacy endpoints were significantly better in the CAR T-cell group than in the control group (N = 247) (median PFS: 3 months; median OS: 4.7 months; p < 0.001). This series represents the largest cohort of PCNSL treated with CAR T-cells reported worldwide. CAR T-cells are effective in relapsed PCNSL, with a high rate of long-term remission and a reassuring tolerance profile. The results seem clearly superior to those usually observed in this setting.

Prognostic Value of CSF IL-10 at Early Assessment of Induction Chemotherapy in Primary CNS Lymphomas: A LOC Network Study

OBJECTIVES

Despite a high response rate at the first evaluation during induction chemotherapy, the risk of early relapse remains high and unpredictable in primary CNS lymphomas (PCSNLs). We aimed to assess the prognostic value of early IL-10 levels in CSF (e-IL-10) after 2 months of induction chemotherapy.

METHODS

We retrospectively selected from the LOC (Lymphomes Oculo-Cérébraux) network database patients with PCSNLs who had complete or partial response at the 2-month evaluation of a high-dose methotrexate-based first-line chemotherapy for whom e-IL-10 was available.

RESULTS

Thirty patients (median age: 62 years, brain involvement in 30/30, CSF involvement in 10/30, median baseline CSF IL-10: 27.5 pg/mL) met the selection criteria. e-IL-10 was undetectable in 22 patients and detectable in 8 patients. At the end of induction treatment, 7 of 8 and 4 of 22 of the patients with detectable and undetectable e-IL-10 had experienced progressive disease, respectively (p = 0.001, OR: 26.8, 95% CI 2-1,478). The median progression-free survival times were 5.8 months (95% CI 2.8-8.8) and 28.7 months (95% CI 13.4-43.9) in the groups with detectable and undetectable e-IL-10, respectively (p < 0.001).

DISCUSSION

Our results suggest that despite an objective response, the persistence of detectable e-IL-10 is associated with a high risk of early relapse in PCNSL. A closer follow-up of such patients is warranted.

Primary central nervous system lymphomas in immunocompromised patients require specific response criteria

PURPOSE

Immunosuppression is a well-established risk factor for primary central nervous system lymphomas (PCNSLs), which present in this context distinct radiological characteristics. Our aim was to describe the radiological evolution of treated PCNSL in immunocompromised patients and suggest adapted MRI response criteria.

METHODS

We conducted a multicenter retrospective study of patients from the French LOC, K-Virogref and CANCERVIH network databases and enrolled adult immunocompromised patients with newly diagnosed PCNSL.

RESULTS

We evaluated the baseline, intermediate, end-of-treatment and follow-up MRI data of 31 patients (9 living with HIV, 16 with solid organ transplantation and 6 with an autoimmune disease under chronic immunosuppressive therapy). At baseline, 23/30 (77%) patients had necrotic lesions with ring enhancement and 28% of the lesions were hemorrhagic. At the end of the first-line treatment, 12/28 (43%) patients could not be classified according to the IPCG criteria. Thirteen of 28 (46%) patients still harbored contrast enhancement, and 11/28 (39%) patients had persistent large necrotic lesions with a median diameter of 15 mm. These aspects were not associated with a pejorative outcome and progressively diminished during follow-up. Six patients relapsed; however, we failed to identify any neuroimaging risk factors on the end-of-treatment MRI.

CONCLUSION

In immunocompromised patients, PCNSLs often harbor alarming features on end-of-treatment MRI, with persistent contrast-enhanced lesions frequently observed. However, these aspects seemed to be related to the necrotic and hemorrhagic nature of the lesions and were not predictive of a pejorative outcome. Specific response criteria for this population are thereby proposed.

Prognosis of glioblastoma patients improves significantly over time interrogating historical controls

BACKGROUND

Glioblastoma (GBM) is the most common devastating primary brain cancer in adults. In our clinical practice, median overall survival (mOS) of GBM patients seems increasing over time.

METHODS

To address this observation, we have retrospectively analyzed the prognosis of 722 newly diagnosed GBM patients, aged below 70, in good clinical conditions (i.e. Karnofsky Performance Status -KPS- above 70%) and treated in our department according to the standard of care (SOC) between 2005 and 2018. Patients were divided into two groups according to the year of diagnosis (group 1: from 2005 to 2012; group 2: from 2013 to 2018).

RESULTS

Characteristics of patients and tumors of both groups were very similar regarding confounding factors (age, KPS, MGMT promoter methylation status and treatments). Follow-up time was fixed at 24 months to ensure comparable survival times between both groups. Group 1 patients had a mOS of 19 months ([17.3-21.3]) while mOS of group 2 patients was not reached. The recent period of diagnosis was significantly associated with a longer mOS in univariate analysis (HR=0.64, 95% CI [0.51 - 0.81]), p < 0.001). Multivariate Cox analysis showed that the period of diagnosis remained significantly prognostic after adjustment on confounding factors (adjusted Hazard Ratio (aHR) 0.49, 95% CI [0.36-0.67], p < 0.001).

CONCLUSION

This increase of mOS over time in newly diagnosed GBM patients could be explained by better management of potentially associated non-neurological diseases, optimization of validated SOC, better management of treatments side effects, supportive care and participation in clinical trials.

Interim FDG-PET improves treatment failure prediction in primary central nervous system Lymphoma: a LOC network prospective multicentric study

PURPOSE

The purpose of our study was to assess the predictive and prognostic role of 2-18F-fluoro-2-deoxy-D-glucose (FDG) PET/MRI during high-dose methotrexate-based chemotherapy (HD-MBC) in de novo primary central nervous system lymphoma (PCNSL) patients aged 60 and above.

METHODS

This prospective multicentric ancillary study included 65 immunocompetents patients who received induction HD-MBC as part of the BLOCAGE01 phase III trial. FDG-PET/MRI were acquired at baseline, post two cycles (PET/MRI2), and post-treatment (PET/MRI3). FDG-PET response was dichotomized, with "positive" indicating persistent tumor uptake higher than the contralateral mirroring brain region. Performances of FDG-PET and International PCNSL Collaborative Group criteria in predicting induction response, progression-free survival (PFS), and overall survival (OS) were compared.

RESULTS

Of 48 PET2 scans performed, nine were positive and aligned with a partial response (PR) on MRI2. Among these, eight (89%) progressed by the end of the induction phase. In contrast, 35/39 (90%) of PET2-negative patients achieved complete response (CR). Among the 18 discordant responses at interim (PETCR/MRIPR), 83% ultimately achieved CR. 87% of the PET2-negative patients were disease-free at 6 months versus 11% of the PET2-positive patients (p<0.001). The MRI2 response did not significantly differentiate patients based on their PFS, regardless of whether they were in CR or PR. Both PET2 and MRI2 independently predicted OS in multivariate analysis, with PET2 showing stronger association.

CONCLUSION

Our study highlights the potential of interim FDG-PET for early management of PCNSL patients. Response-driven treatment based on PET2 may guide future clinical trials.

Epileptic seizures in patients with primary central nervous system lymphoma: A systematic review

BACKGROUND

Primary central nervous system lymphoma (PCNSL) accounts for less than 5% of primary brain tumors. Epileptic seizures are a common manifestation of brain tumors; however, literature on the prevalence, characteristics, and oncological implications of seizures in patients with PCNSL is limited, and the management of antiepileptic drugs (AEDs) is unclear. This review aimed to summarize the existing knowledge on seizures in PCNSL, their potential association with surgery, oncological treatment, survival rates, and management of AEDs.

METHODS

A systematic review was performed according to the PRISMA recommendations and included articles published between 1953 and 2023 describing seizures in patients with PCNSL.

RESULTS

The search identified 282 studies, of which 21 were included. Up to 33% of patients with PCNSL developed seizures, mostly at the initial presentation. Little information was found on changes in seizure incidence through the course of the disease, and no details were found on seizure frequency, the percentage of treatment-resistant patients, or the evolution of seizures at remission. Younger age, cortical location, and immunodeficiency have been identified as potential risk factors for seizures, but evidence is very limited. The growing use of vigorous treatments including intensive chemotherapy with autologous stem cell transplantation and immunotherapy with CAR-T cells is associated with a higher incidence of seizures. The association between seizure development and patient mortality in PCNSL remains unknown. There are no data on AED prophylaxis or the use of specific AEDs in PCNSL.

CONCLUSIONS

Further studies are needed to investigate seizures in larger cohorts of PCNSL, to clarify their prevalence, better characterize them, identify risk factors, analyze survival rates, and make recommendations on AED management. We recommend following general practice guidelines for seizures symptomatic of brain tumors and not to prescribe AED prophylaxis in PCNSL.

CAR T-cell therapy for central nervous system lymphomas: blood and cerebrospinal fluid biology, and outcomes

Not available.

[18F]FDG PET-MRI provides survival biomarkers in primary central nervous system lymphoma in the elderly: an ancillary study from the BLOCAGE trial of the LOC network

PURPOSE

Primary central nervous system lymphoma (PCNSL) incidence is rising among elderly patients, presenting challenges due to poor prognosis and treatment-related toxicity risks. This study explores the potential of combining [18F]fluorodeoxyglucose ([18F]FDG) PET scans and multimodal MRI for improving management in elderly patients with de novo PCNSL.

METHODS

Immunocompetent patients over 60 years with de novo PCNSL were prospectively enrolled in a multicentric study between January 2016 and April 2021. Patients underwent brain [18F]FDG PET-MRI before receiving high-dose methotrexate-based chemotherapy. Relationships between extracted PET (metabolic tumor volume (MTV), sum of MTV for up to five lesions (sumMTV), metabolic imaging lymphoma aggressiveness score (MILAS)) and MRI parameters (tumor contrast-enhancement size, cerebral blood volume (CBV), cerebral blood flow (CBF), apparent diffusion coefficient (ADC)) and treatment response and outcomes were analyzed.

RESULTS

Of 54 newly diagnosed diffuse large B-cell PCNSL patients, 52 had positive PET and MRI with highly [18F]FDG-avid and contrast-enhanced disease (SUVmax: 27.7 [22.8-36]). High [18F]FDG uptake and metabolic volume were significantly associated with low ADCmean values and high CBF at baseline. Among patients, 69% achieved an objective response at the end of induction therapy, while 17 were progressive. Higher cerebellar SUVmean and lower sumMTV at diagnosis were significant predictors of complete response: 6.4 [5.7-7.7] vs 5.4 [4.5-6.6] (p = 0.04) and 5.5 [2.1-13.3] vs 15.9 [4.2-19.5] (p = 0.01), respectively. Two-year overall survival (OS) was 71%, with a median progression-free survival (PFS) of 29.6 months and a median follow-up of 37 months. Larger tumor volumes on PET or enhanced T1-weighted MRI were significant predictors of poorer OS, while a high MILAS score at diagnosis was associated with early death (< 1 year).

CONCLUSION

Baseline cerebellar metabolism and sumMTV may predict response to end of chemotherapy in PCNSL. Tumor volume and MILAS at baseline are strong prognostic factors.

First line treatments in primary central nervous system lymphomas in young patients

PURPOSE OF REVIEW

The aim of this review is to provide an update on current first-line treatments as well as on-going studies in immunocompetent patients with primary central nervous system lymphomas.

RECENT FINDINGS

High-dose methotrexate (HD-MTX)-based polychemotherapy is widely used in induction treatment (IT). Among HD-MTX-based regimens, the best association is not yet defined. IT should be followed by a consolidation or a maintenance according to patient's age and performance status. Thiotepa-based intensive chemotherapy (IC) followed by autologous stem cell transplantation (ASCT) has improved survival in eligible patients compared to a nonmyeloablative consolidation. Because of the high risk of neurotoxicity, conventional whole brain radiotherapy (WBRT; 36-40 Gy) has been abandoned. Reduced-WBRT (23.4 Gy) is an alternative option in patients under 60 years-old in complete response after IT. Its safety remains to be demonstrated in elderly patients. The benefit of maintenance strategies to reduce the risk of relapse is being assessed in several studies in patients beyond 70 years-old.

SUMMARY

HD-MTX-based polychemotherapy remains the corner stone of the IT, but the best regimen is not yet defined. Clinical trials assessing new IT regimens are ongoing. Intensive consolidation with IC + ASCT benefits patients up to 70 years-old. Predictive factors are under investigation to better define therapeutic response and guide treatment adjustment.

Radiotherapy for newly diagnosed primary central nervous system lymphoma: role and perspective

Whole brain radiotherapy (WBRT) has long been a key treatment of newly diagnosed primary central nervous system lymphoma (PCNSL). In the 1990s, the addition of high dose Methotrexate-based induction chemotherapy (HD MTX-based CT) has enabled a drastic improvement in PCNSL patients outcome. However, combined treatment has led to radiation-induced delayed neurotoxicity, especially in older patients. Alternative treatment strategies have been assessed to improve the efficacy and neurotoxicity ratio. Nowadays, in the elderly patients WBRT is widely omitted or deferred, and in younger patients WBRT is challenged by high dose chemotherapy with autologous stem cell transplant (HCT-ASCT) for consolidation treatment after HD MTX-based CT. In this setting, this review is addressed to clinicians with the aim to summarize the role of WBRT in the treatment of newly diagnosed PCNSL and its perspectives.

Brain radiotherapy in patients treated for a newly diagnosed primary central nervous system lymphoma: professional practice evaluation in 19 French centers

INTRODUCTION

The objective of this study was a multicentric evaluation of professional practices, analyzing the irradiation technique itself and its impact on survival and recurrence sites, in primary central nervous system lymphomas (PCNSLs).

METHODS

We retrospectively analyzed the technical and clinical records of 79 PCNSL patients included in the database of the national expert network for oculocerebral lymphoma ('LOC') who were treated with brain radiotherapy as first-line treatment for newly diagnosed primary central nervous system lymphoma between 2011 and 2018.

RESULTS

The number of patients treated with brain radiotherapy gradually decreased over time. The heterogeneity of radiotherapy prescriptions was significant, and 55% of them did not comply with published recommendations in terms of irradiation dose and/or volume. The proportion of complete responders to induction chemotherapy treated with reduced-dose radiotherapy increased over time. Partial brain radiotherapy was associated with significantly lower overall survival in univariate analysis. In partial responders to induction chemotherapy, increasing the total dose to the brain >30 Gy and adding a boost to the WBRT induced a trend toward improved progression-free and overall survival. Five recurrences (13%) occurred exclusively in the eyes, all in patients whose eyes had been excluded from the irradiation target volume and including 2 patients without ocular involvement at diagnosis.

CONCLUSION

The visibility of recommendations for prescribing brain radiotherapy for the treatment of newly diagnosed primary central nervous system lymphoma needs to be improved to harmonize practices and improve their quality. We propose an update of the recommendations.

Mismatch Repair Deficiency and Lynch Syndrome Among Adult Patients With Glioma

PURPOSE

The Lynch syndrome (LS)-glioma association is poorly documented. As for mismatch repair deficiency (MMRd) in glioma, a hallmark of LS-associated tumors, there are only limited data available. We determined MMRd and LS prevalence in a large series of unselected gliomas, and explored the associated characteristics. Both have major implications in terms of treatment, screening, and prevention.

METHODS

Somatic next-generation sequencing was performed on 1,225 treatment-naive adult gliomas referred between 2017 and June 2022. For gliomas with ≥1 MMR pathogenic variant (PV), MMR immunohistochemistry (IHC) was done. Gliomas with ≥1 PV and protein expression loss were considered MMRd. Eligible patients had germline testing. To further explore MMRd specifically in glioblastomas, isocitrate dehydrogenase (IDH)-wild type (wt), we performed IHC, and complementary sequencing when indicated, in a series of tumors diagnosed over the 2007-2021 period.

RESULTS

Nine gliomas were MMRd (9/1,225; 0.73%). Age at glioma diagnosis was <50 years for all but one case. Eight were glioblastomas, IDH-wt, and one was an astrocytoma, IDH-mutant. ATRX (n = 5) and TP53 (n = 8) PV were common. There was no TERT promoter PV or EGFR amplification. LS prevalence was 5/1,225 (0.41%). One 77-year-old patient was a known LS case. Four cases had a novel LS diagnosis, with germline PV in MSH2 (n = 3) and MLH1 (n = 1). One additional patient had PMS2-associated constitutional mismatch repair deficiency. Germline testing was negative in three MSH6-deficient tumors. In the second series of glioblastomas, IDH-wt, MMRd prevalence was 12.5% in the <40-year age group, 2.6% in the 40-49 year age group, and 1.6% the ≥50 year age group.

CONCLUSION

Screening for MMRd and LS should be systematic in glioblastomas, IDH-wt, diagnosed under age 50 years.

Recent advances in the diagnosis and the treatment of primary CNS lymphoma

This review focuses on the recent progress in the management of primary central nervous system lymphoma (PCNSL). Multiomic analyses allowed to better understand the tumorigenesis of PCNSL and to establish a molecular classification with prognostic value that will optimize patient management and guide future targeted approaches. Cooperative clinical trials have demonstrated the feasibility and efficacy, in selected fit patients, of high-dose chemotherapy with autologous stem cell transplantation as post-induction consolidation, that will progressively replace whole brain radiotherapy associated with a much higher risk of delayed neurotoxicity. Several novel treatments have shown efficacy and overall good tolerance in PCNSL patients, such as Bruton's tyrosine kinase (BTK) inhibitors, imids, immune checkpoint inhibitors and chimeric antigen receptor T-cells (CAR-T). This opens promising therapeutic perspectives to improve the current standard treatment, especially for elderly and unfit patients who represent a growing population.

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.

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.

CSF biomarkers in primary CNS lymphoma

PCNSL is a non-Hodgkin lymphoma (NHL) affecting brain, spinal cord, eyes and leptomeninges. In the past two decades, its prognosis significantly improved due to therapeutic advances but it remains a highly aggressive tumor and early diagnosis is necessary for optimal management. Diagnosis relies on the identification of lymphoma cells in brain tissue obtained by stereotactic biopsy. Alternatively, lymphoma cells may be found in CSF through lumbar puncture (LP) or by a vitrectomy. For several reasons, the diagnosis of PCNSL may be challenging. Misleading radiological presentations are frequent. Dramatic response to steroids may bias histological analysis and deep brain location or frail health status can contraindicate brain biopsy. In the follow-up of patients who have been previously treated, differential diagnosis between tumor relapse and post-treatment may be also difficult. Therefore, the development of complementary reliable diagnostic tools is needed. This review will summarize several diagnostic or prognostic CSF biomarkers which have been proposed in PCNSL, their interests and limits.

Molecular and clinical diversity in primary central nervous system lymphoma

BACKGROUND

Primary central nervous system lymphoma (PCNSL) is a rare and distinct entity within diffuse large B-cell lymphoma presenting with variable response rates probably to underlying molecular heterogeneity.

PATIENTS AND METHODS

To identify and characterize PCNSL heterogeneity and facilitate clinical translation, we carried out a comprehensive multi-omic analysis [whole-exome sequencing, RNA sequencing (RNA-seq), methylation sequencing, and clinical features] in a discovery cohort of 147 fresh-frozen (FF) immunocompetent PCNSLs and a validation cohort of formalin-fixed, paraffin-embedded (FFPE) 93 PCNSLs with RNA-seq and clinico-radiological data.

RESULTS

Consensus clustering of multi-omic data uncovered concordant classification of four robust, non-overlapping, prognostically significant clusters (CS). The CS1 and CS2 groups presented an immune-cold hypermethylated profile but a distinct clinical behavior. The 'immune-hot' CS4 group, enriched with mutations increasing the Janus kinase (JAK)-signal transducer and activator of transcription (STAT) and nuclear factor-κB activity, had the most favorable clinical outcome, while the heterogeneous-immune CS3 group had the worse prognosis probably due to its association with meningeal infiltration and enriched HIST1H1E mutations. CS1 was characterized by high Polycomb repressive complex 2 activity and CDKN2A/B loss leading to higher proliferation activity. Integrated analysis on proposed targets suggests potential use of immune checkpoint inhibitors/JAK1 inhibitors for CS4, cyclin D-Cdk4,6 plus phosphoinositide 3-kinase (PI3K) inhibitors for CS1, lenalidomide/demethylating drugs for CS2, and enhancer of zeste 2 polycomb repressive complex 2 subunit (EZH2) inhibitors for CS3. We developed an algorithm to identify the PCNSL subtypes using RNA-seq data from either FFPE or FF tissue.

CONCLUSIONS

The integration of genome-wide data from multi-omic data revealed four molecular patterns in PCNSL with a distinctive prognostic impact that provides a basis for future clinical stratification and subtype-based targeted interventions.

Isolated intraocular relapses of primary cerebral lymphomas: An LOC network study

Most relapses of primary central nervous system lymphoma (PCNSL) occur in the brain and are associated with a poor prognosis. Isolated intraocular relapses (IIORs) are rare and poorly described. We retrospectively selected from the French Lymphome Oculo-Cérébral database PCNSL patients who initially presented with cerebral localization and who experienced IIOR during the course of the disease. Of the 1472 patients included in the database, 55 patients presented an IIOR. Their median age was 68 years, and median Karnofsky Performance Status 80. IL-10 levels in the aqueous humor and/or in the vitreous were increased in 42/46 patients. 45/55 patients received systemic chemotherapy, and 11/55 received high-dose chemotherapy with autologous stem cell transplantation (HCT-ASCT) as consolidation treatment. After a median follow-up of 69 months, 42/55 patients had relapsed, including 90% of the patients who did not receive HCT-ASCT at IIOR and 40% of the patients who received HCT-ASCT at IIOR (p < 0.001). The first relapse after the initial IIOR was exclusively in the eye in 23/42 patients, and 29/42 patients had a subsequent brain relapse during the course of the disease. The median progression-free survival, brain-free survival and overall survival from IIOR were 12.2, 48.6 and 57.1 months, respectively. Isolated intraocular relapse is not exceptional in the course of PCNSL and deserves systematic ophthalmological follow-up. Its prognosis is much better than the prognosis of brain relapse, with an evolution close to that of primary vitreoretinal lymphoma. With the exception of patients who received HCT-ASCT at IIOR, almost all patients subsequently relapsed, often with other IIORs.

Prognostic factors in primary central nervous system lymphoma

PURPOSE OF REVIEW

Primary central nervous system lymphoma (PCNSL) is a rare and aggressive extranodal diffuse large B cell lymphoma. Despite its apparent immunopathological homogeneity, PCNSL displays a wide variability in outcome. Identifying prognostic factors is of importance for patient stratification and clinical decision-making. The purpose of this review is to focus on the clinical, neuroradiological and biological variables correlated with the prognosis at the time of diagnosis in immunocompetent patients.

RECENT FINDINGS

Age and performance status remain the most consistent clinical prognostic factors. The current literature suggests that neurocognitive dysfunction is an independent predictor of poor outcome. Cumulating data support the prognostic value of increased interleukin-10 level in the cerebrospinal fluid (CSF), in addition to its interest as a diagnostic biomarker. Advances in neuroimaging and in omics have identified several semi-quantitative radiological features (apparent diffusion restriction measures, dynamic contrast-enhanced perfusion MRI (pMRI) pattern and 18F-fluorodeoxyglucose metabolism) and molecular genetic alterations with prognostic impact in PCNSL.

SUMMARY

Validation of new biologic and neuroimaging markers in prospective studies is required before integrating future prognostic scoring systems. In the era of radiomic, large clinicoradiological and molecular databases are needed to develop multimodal artificial intelligence algorithms for the prediction of accurate outcome.

P11.09.B Chemotherapy is an efficient treatment in primary CNS MALT lymphoma

Background

Mucosae-associated lymphoid tissue (MALT) lymphomas are a rare and still poorly understood form of primary central nervous system lymphoma (PCNSL). The aim of this study was to better describe these tumors and their management, and to better appreciate their long-term prognosis after treatment.

Material and Methods

Adult immunocompetent patients with primary CNS MALT lymphoma (PCNSML) were retrospectively selected from the database on PCNSL of the Pitié-Salpêtrière Hospital. All cases had double-read for pathology.

Results

Eleven PCNSML representing 1.7% of the 662 PCNSL included in the database were selected, There were 9 women and two men, all immunocompetent. Their median age was 56 years (min 29; max 78). The median time from first symptoms to diagnosis was 13 months and the median KPS at diagnosis was 90. Location was dural in 8 cases, suggestive of meningioma in 7 cases and of subdural hematoma in 1 case, and parenchymal in 3 cases. The disease was unifocal/localized in 4 cases and multifocal/diffuse in 7 cases. In 3 cases, it was the second reading that allowed making the diagnosis. In first-line treatment, all patients received chemotherapy (CT): “systemic” CT, i.e usually used in systemic MALT lymphomas, in 7 cases (n=7) and “CNS” CT, i.e usually used in CNS lesions in 4 cases. CT was preceded by surgery in 4 cases. No patient received radiotherapy in first line. According to the IPCG (International PCNSL Collaborative Group) criteria, the overall response rate was 7/11 (64%). At latest news, 5 patients had a persistent contrast enhancement, stable without any treatment since a median of 57 months, raising the question of complete response despite persisting contrast enhancement. No patient developed neurotoxicity except for one of the 2 patients who subsequently received radiotherapy. The median follow-up was 109 months. The median progression-free survival was 78.0 months (95% CI [43.4;NA[) and the 10-year overall survival rate was 90% (95% CI [0.7;1[).

Conclusion

This series confirms the classical clinical and radiological presentation of PCNSML. Compared to the literature where the treatment was based on radiotherapy in almost two thirds of cases, the therapeutic approach presented here appears unconventional. This is the first series demonstrating that chemotherapy is an efficient treatment in PCNSML, with an excellent long-term outcome and the absence of neurotoxicity, and calling into question the relevance of the IPCG criteria for the evaluation of their therapeutic response.

Radiotherapy or Autologous Stem-Cell Transplantation for Primary CNS Lymphoma in Patients Age 60 Years and Younger: Long-Term Results of the Randomized Phase II PRECIS Study

Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned co-primary or secondary analyses are not yet available. Clinical Trial Updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported.We previously reported the results of a randomized phase II study in patients with newly diagnosed primary CNS lymphoma (age 18-60 years). Patients were treated with high-dose methotrexate-based induction chemotherapy followed by whole-brain radiotherapy (WBRT) or high-dose chemotherapy (thiotepa-busulfan-cyclophosphamide) with autologous stem-cell transplantation (ASCT). The median follow-up was 33 months. In this report, we provide long-term data (median follow-up, 8 years) regarding the outcomes and toxicities. Fifty-three and 44 patients received induction chemotherapy followed by WBRT or ASCT, respectively. Their 8-year event-free survival from random assignment was 67% and 39% in the ASCT and WBRT arms, respectively (P = .03), with a significantly lower risk of relapse after ASCT (hazard ratio = 0.13, P < .001). One third of patients who relapsed after WBRT were alive after salvage treatment. Five and four patients died of ASCT and WBRT-related toxicities, respectively. The 8-year overall survival was 69% and 65% in the ASCT and WBRT arms, respectively (not significant). Balance (52% v 10%, P ≤ 0.001) and neurocognition (64% v 13%, P < .001) significantly deteriorated after WBRT compared with ASCT during the follow-up. This study shows that 40 Gy WBRT should be avoided in first-line treatment because of its neurotoxicity and suboptimal efficacy in reducing relapses while ASCT appears to be highly efficient in preventing relapses.