Long-term efficacy, safety and neurotolerability of MATRix regimen followed by autologous transplant in primary CNS lymphoma: 7-year results of the IELSG32 randomized trial

Targets and treatments in primary CNS lymphoma

Primary central nervous system lymphoma (PCNSL) is a rare and highly aggressive lymphoma entirely localized in the central nervous system or vitreoretinal space. PCNSL generally initially responds to methotrexate-containing chemotherapy regimens, but progressive or relapsing disease is common, and the prognosis is poor for relapsed or refractory (R/R) patients. PCNSL is often characterized by activation of nuclear factor kappa B (NF-κB) due to mutations in the B-cell receptor (BCR) or toll-like receptor (TLR) pathways, as well as immune evasion. Targeted treatments that inhibit key PCNSL mechanisms and pathways are being evaluated; inhibition of Bruton's tyrosine kinase (BTK) downstream of BCR activation has demonstrated promising results in treating R/R disease. This review will summarize the evidence and potential for targeted therapeutic agents to improve treatment outcomes in PCNSL. This includes immunotherapeutic and immunomodulatory approaches and inhibitors of the key pathways driving PCNSL, such as aberrant BCR and TLR signaling.

Survival, neurocognitive function, and health-related quality of life outcomes after rituximab-methotrexate, BCNU, teniposide, and prednisolone for primary CNS lymphoma: Final results of the HOVON 105/ALLG NHL 24 study

BACKGROUND

Studies on the efficacy of rituximab in primary CNS lymphoma (PCNSL) reported conflicting results. Our international randomized phase 3 study showed that the addition of rituximab to high-dose methotrexate, BCNU, teniposide, and prednisolone (MBVP) in PCNSL was not efficacious in the short term. Here we present long-term results after a median follow-up of 82.3 months.

METHODS

One hundred and ninety-nine eligible newly diagnosed, nonimmunocompromised patients with PCNSL aged 18-70 years with WHO performance status 0-3 was randomized between treatment with MBVP chemotherapy with or without rituximab, followed by high-dose cytarabine consolidation in responding patients, and reduced-dose WBRT in patients aged ≤ 60 years. Event-free survival was the primary endpoint. Overall survival rate, neurocognitive functioning (NCF), and health-related quality of life (HRQoL) were additionally assessed, with the IPCG test battery, EORTC QLQ-C30 and QLQ-BN20 questionnaires, respectively.

RESULTS

For event-free survival, the hazard ratio was 0.85, 95% CI 0.61-1.18, P = .33. Overall survival rate at 5 years for MBVP and R-MBVP was 49% (39-59) and 53% (43-63) respectively. In total, 64 patients died in the MBVP arm and 55 in the R-MBVP arm, of which 69% were due to PCNSL. At the group level, all domains of NCF and HRQoL improved to a clinically relevant extent after treatment initiation, and remained stable thereafter up to 60 months of follow-up, except for motor speed which deteriorated between 24 and 60 months. Although fatigue improved initially, high levels persisted in the long term.

CONCLUSIONS

Long-term follow-up confirms the lack of added value of rituximab in addition to MBVP and HD-cytarabine for PCNSL.

Survival outcomes and treatment experience of 124 patients with primary central nervous system lymphoma

PURPOSE

Primary central nervous system lymphoma (PCNSL) is a rare malignancy of the central nervous system with high invasiveness. There is little consensus on the treatment of PCNSL. This study retrospectively studied data from PCNSL patients in a single center to summarize treatment experience and explore prognostic factors.

METHODS

Survival curves were drawn using the Kaplan-Meier method and prognostic factors were analyzed using Cox's hazards model.

RESULTS

In multivariate analysis, cerebrospinal fluid lactic acid dehydrogenase (CSF LDH; p = 0.005 and p = 0.002), neutrophil to lymphocyte ratio (NLR; p = 0.014 and p = 0.038), and completion of four cycles of induction therapy (p < 0.001and p < 0.001) were significant and independent predictors of overall survival (OS) and progression-free survival (PFS), respectively.

CONCLUSION

On the basis of this study, we propose that PCNSL patients should receive early induction therapy with sufficient cycles. Subsequent consolidation therapy can prevent relapses and improve survival. In patients with PCNSL, the independent prognostic factors for OS and PFS were CSF LDH level, NLR, and full cycles of induction therapy.

Prognostic value of POD18 combined with improved IELSG in primary central nervous system lymphoma

PURPOSE

The International Extranodal Lymphoma Study Group (IELSG) score is widely used in clinical practice to stratify the risk of primary central nervous system lymphoma (PCNSL) patients. Our study aims to confirm and improve the IELSG score in PCNSL patients based on Chinese populations.

MATERIALS AND METHODS

A total of 79 PCNSL patients were retrospectively analyzed. All patients treated with high-dose methotrexate (HD-MTX)-based therapy collected clinical data. The receiver-operating characteristic (ROC) curve was used to determine the optimal cut-off values for the factors in IELSG score. Progression of disease (POD) at the most landmark time point was determine by Epanechnikov kernel and the area under the ROC curve (AUROC). Kaplan-Meier and multivariable regression methods were used to analyze survival data. Nomogram was generated for calculating the weight of each selected factor.

RESULTS

The traditional IELSG score had no significant difference on OS and PFS except ECOG ≥ 2 and could not stratify the risk groups in PCNSL. The improved IELSG scoring system was established, which incorporated age ≥ 54 years, ECOG ≥ 2, deep brain structure, elevated CSF protein, and LDH/ULN > 0.75. On the other hand, POD18 was identified as a new powerful prognostic factor for PCNSL. In multivariate analysis, POD18 and the improved IELSG scoring system were independent prognostic factors for OS. Nomogram including the two significant variables showed the best performance (C-index = 0.828).

CONCLUSIONS

In this study, the IELSG score was improved and a new prognostic indicator POD18 was incorporated to construct a nomogram prognostic model, thereby further improving the predictive ability of the model.

Diagnostic, Pathologic, and Therapeutic Considerations for Primary CNS Lymphoma

Primary CNS lymphoma (PCNSL) is a rare lymphoma representing 3% of CNS malignancies. The diagnosis is complicated by the unique risks associated with brain biopsy, and the treatment is similarly complicated by the restriction of effective therapeutics able to cross the blood-brain barrier. Currently, the majority of individuals diagnosed with this disease are immunocompetent although immune deficiency related to HIV or immunosuppressive therapy remains an important risk factor. Improvements in both frontline therapy and consolidation options, including the use of hematopoietic stem-cell transplantation, have translated to improved survival. Unfortunately, patients experiencing relapsed or refractory disease often fare poorly. Here, we review key clinical, pathologic, and therapeutic aspects of PCNSL and highlight challenging clinical scenarios that may be encountered by the treating oncologist.

Case report: Successful treatment of a patient with relapsed/refractory primary central nervous system lymphoma with thiotepa-based induction, autologous stem cell transplantation and maintenance

Despite significant improvements in prognosis, a subset of patients with primary central nervous system lymphoma (PCNSL) remains at high risk for relapse. The treatment of relapsed and refractory (R/R) PCNSL remains a major clinical challenge. Herein, we present a 24-year-old patient with PCNSL who relapsed 4 years after initial diagnosis and subsequently became refractory to high-dose methotrexate (HD-MTX), temozolomide, whole brain radiation therapy (WBRT), ibrutinib, and lenalidomide. She received thiotepa with anti-programmed cell death protein 1 (PD-1) antibody and achieved partial remission and then underwent autologous stem cell transplantation (ASCT) with thiotepa-based conditioning. Post-transplant maintenance with thiotepa and anti-PD-1 at 3-month intervals resulted in a durable complete response (CR) in this case of R/R PCNSL. Our report highlights the important role of thiotepa in the treatment of patients with R/R PCNSL.

A Systematic Review of Cognitive Function, Anxiety, and Depression in Patients With Newly Diagnosed Primary Central Nervous System Lymphoma

OBJECTIVE

To retrospectively analyze the effects of different treatments on cognitive functioning, anxiety, and depression in patients with primary central nervous system lymphoma (PCNSL).

METHODS

A comprehensive literature search was conducted in multiple databases including the Cochrane Library, CINAHL, PubMed, Web of Science, EMBASE, Sino Med, Wei Pu, Wan Fang, CNKI, and Google Scholar. The search included studies published through June 20, 2023, focusing on cognitive function, anxiety, and depression in adult patients newly diagnosed with PCNSL. Various measurement tools and scales were used to assess the primary outcomes. Descriptive systematic reviews were conducted to integrate the literature and summarize the effects of different treatment modalities on cognitive functioning, anxiety, and depression in PCNSL patients. This review was registered with PROSPERO (CRD42022370250).

RESULTS

A total of 43 studies were included. Induction chemotherapy was associated with improved cognitive function and reduced anxiety and depression in the majority of patients. Whole-brain radiotherapy (WBRT) was found to lead to cognitive impairment, particularly in executive, attention, memory, and motor function. Low-dose WBRT, autologous stem cell transplantation (ASCT), and blood-brain barrier disruption (BBBD) treatments did not result in significant cognitive impairment. Anxiety and depression were observed to decrease over the long term.

CONCLUSIONS

Overall, the cognitive functioning, anxiety, and depression of patients with PCNSL can be improved with appropriate treatments. However, patients treated with WBRT are at a higher risk of cognitive decline compared to those receiving other treatment modalities. Therefore, special attention should be given to patients undergoing WBRT, and a comprehensive analysis should be conducted to reduce neurotoxicity and address early cognitive problems in these patients.

Neurotoxicity and management of primary and secondary central nervous system lymphoma after adoptive immunotherapy with CD19-directed chimeric antigen receptor T-cells

BACKGROUND

Chimeric antigen receptor (CAR) T-cells targeting CD19 have been established as a leading engineered T-cell therapy for B-cell lymphomas; however, data for patients with central nervous system (CNS) involvement are limited.

METHODS

We retrospectively report on CNS-specific toxicities, management, and CNS response of 45 consecutive CAR T-cell transfusions for patients with active CNS lymphoma at the Massachusetts General Hospital over a 5-year period.

RESULTS

Our cohort includes 17 patients with primary CNS lymphoma (PCNSL; 1 patient with 2 CAR T-cell transfusions) and 27 patients with secondary CNS lymphoma (SCNSL). Mild ICANS (grade 1-2) was observed after 19/45 transfusions (42.2%) and severe immune effector cell-associated neurotoxicity syndrome (ICANS) (grade 3-4) after 7/45 transfusions (15.6%). A larger increase in C-reactive protein (CRP) levels and higher rates of ICANS were detected in SCNSL. Early fever and baseline C-reactive protein levels were associated with ICANS occurrence. CNS response was seen in 31 cases (68.9%), including a complete response of CNS disease in 18 cases (40.0%) which lasted for a median of 11.4 ± 4.5 months. Dexamethasone dose at time of lymphodepletion (but not at or after CAR T-cell transfusion) was associated with an increased risk for CNS progression (hazard ratios [HR] per mg/d: 1.16, P = .031). If bridging therapy was warranted, the use of ibrutinib translated into favorable CNS-progression-free survival (5 vs. 1 month, HR 0.28, CI 0.1-0.7; P = .010).

CONCLUSIONS

CAR T-cells exhibit promising antitumor effects and a favorable safety profile in CNS lymphoma. Further evaluation of the role of bridging regimens and corticosteroids is warranted.

Central Nervous System Lymphoma

Central nervous system lymphoma (CNSL) is a rare and aggressive malignancy that primarily affects the brain, spinal cord, and meninges. This article provides a comprehensive overview of the current understanding of CNSL encompassing its epidemiology, pathophysiology, clinical presentation, diagnosis, treatment modalities, and prognosis. Although the main focus is on primary CNS lymphoma (PCNSL), ocular lymphoma, primary leptomeningeal lymphoma, and secondary CNS lymphoma are also discussed. The pathobiology of CNSL involves the infiltration of malignant lymphocytes within the CNS parenchyma or leptomeninges. Various risk factors and immunological mechanisms contribute to its development, including immunodeficiency states, chronic inflammation, and genomic alterations. Accurate diagnosis is crucial for appropriate management, given the heterogeneous clinical presentation. The neuroimaging, systemic imaging, and other modalities for diagnosis and evaluation for extent of disease involvement will be discussed. Additionally, the importance of histopathological examination, cerebrospinal fluid (CSF) analysis, and molecular testing in confirming the diagnosis and guiding treatment decisions are highlighted. The treatment landscape for CNSL has evolved significantly. Therapeutic approaches encompass a multimodal strategy combining high-dose methotrexate-based chemotherapy, consolidation with whole-brain radiation therapy, and high-dose chemotherapy with stem cell rescue. Recent advancements in targeted therapies and immunomodulatory agents offer promising avenues for future treatment options. We review the clinical outcomes and prognostic factors influencing the survival of CNSL patients, including age, performance status, disease stage, and genetic abnormalities.

Different patterns of failure in two treatment regimens for primary central nervous system lymphoma, a retrospective analysis of 124 cases in Taiwan

To explore prognostic factors and outcomes of primary central nervous system lymphoma (PCNSL) of diffuse large B-cell lymphoma (DLBCL) in Taiwan, 124 PCNSL-DLBCL patients (from 1995 to 2021) were retrospectively analyzed. Mainly, two treatment modalities including sandwich chemoradiotherapy and modified MATRix regimen were employed in these patients. Overall survival (OS) was determined by log-rank test and time-dependent Cox analysis. Median OS of all patients was 27.1 months. 47 (37.9%) patients who underwent sandwich chemoradiotherapy had a complete remission (CR) rate of 87.2%, median OS of 53.9 months, and progression free survival (PFS) of 42.9 months. 11 (8.9%) patients who underwent modified MATRix regimen had CR rate of 72.7%, median OS of 18.9, and PFS of 11.2 months. There are no significant OS differences between treatment groups or addition of Rituximab. Patients treated with the modified MATRix regimen experienced a higher early mortality rate followed by a survival plateau. IELSG low-risk group had significantly improved OS and PFS than IELSG intermediate- or high-risk group. In multivariant analysis, age > 60 years old and bilateral cerebral lesions are associated with significantly inferior OS. Sandwich chemoradiotherapy demonstrated better early survival and reduced treatment-related toxicity for PCNSL patients compared to the modified MATRix regimen. However, the long-term follow-up revealed a higher rate of treatment failure events in the sandwich chemoradiotherapy group. IELSG and MSKCC scores served as reliable risk assessment models. Incorporating bilateral cerebral lesions as a risk factor further improved risk evaluation.

Central Nervous System Lymphoma

OBJECTIVE

This article reviews the clinical presentation, diagnostic workup, staging, and treatment of primary central nervous system (CNS) lymphoma and common manifestations of secondary CNS lymphoma.

LATEST DEVELOPMENTS

Lymphoma can arise in the CNS de novo (primary CNS lymphoma) or as the result of systemic disease (secondary CNS lymphoma). Symptoms may include focal neurologic deficits related to the disease site, cognitive decline, and symptoms of increased intracranial pressure. Standard treatment may differ based on lymphoma subtype and location. A majority of CNS lymphoma is diffuse large B-cell subtype and exhibits aggressive behavior. First-line treatment is generally methotrexate-based polychemotherapy. Response rates to treatment are high, approximately 80% to 90% for primary CNS lymphoma, but relapse is common. Consolidation approaches including myeloablative chemotherapy followed by autologous stem cell rescue, nonmyeloablative chemotherapy, radiation, and medical maintenance regimens reduce rates of relapse. The recent development of targeted agents such as Bruton tyrosine kinase inhibitors and immunomodulatory strategies have shown promise in the treatment of CNS lymphoma. Immunotherapy in the form of checkpoint inhibitors and chimeric antigen receptor T cells is being studied. More indolent forms of lymphoma may be treated with radiation or targeted therapy.

ESSENTIAL POINTS

CNS lymphoma is an uncommon but clinically meaningful manifestation of extranodal lymphoma. The diagnosis requires a high level of suspicion for rapid initiation of potentially curative treatment.

How I treat secondary CNS involvement by aggressive lymphomas

Secondary central nervous system (CNS) lymphoma (SCNSL) is a rare but clinically challenging scenario with historically disappointing outcomes. SCNSL refers to lymphoma that has spread into the CNS concurrently with systemic disease or CNS relapse during or after frontline immunochemotherapy, presenting with or without systemic lymphoma. Diffuse large B-cell lymphoma (DLBCL) denotes the most common entity, but an increased incidence is observed in other histologies, such as Burkitt lymphoma and mantle-cell lymphoma. The incidence, timing in disease course, location, evidence supporting the use of CNS prophylaxis, and treatment pathways vary according to histology. No randomized data exist to delineate the best treatment approaches with current recommendations based on retrospective and single-arm studies. However, a regimen comprising immunochemotherapy, incorporating agents that cross the blood-brain barrier, followed by thiotepa-containing conditioning and autologous stem-cell transplant outlined in the international MARIETTA study demonstrated improvement in outcomes, representing a major accomplishment in the care of patients with DLBCL with SCNSL. Anti-CD19 chimeric antigen receptor T cell denotes a paradigm shift in the treatment of patients with systemic aggressive lymphomas, with emerging data also demonstrating efficacy without higher neurotoxicity in those with SCNSL. In this manuscript we discuss 5 clinical scenarios and review the evidence supporting our recommendations.

Functional Outcome and Overall Survival in Patients with Primary or Secondary CNS Lymphoma after Surgical Resection vs. Biopsy

BACKGROUND

Central nervous system lymphoma (CNSL) is rare form of brain tumour. It manifests either as primary CNS lymphoma (pCNSL) originating within the central nervous system or as secondary CNS lymphoma (sCNSL), arising as cerebral metastases of systemic lymphoma. For a significant period, surgical resection was considered obsolete due to the favourable response to chemotherapy and the associated risk of postoperative deficits. The objective of the present study was to demonstrate the benefits of resection in CNSL patients, including extended survival and improved postoperative function.

METHODS

A retrospective study involving patients diagnosed with either PCNSL or SCNSL that were surgically approached at our neurosurgical department between 2010 and 2022 was conducted. Patients were categorised into three subgroups based on their neurosurgical approach: (1) stereotactical biopsy, (2) open biopsy, (3) resection. We then performed statistical analyses to assess overall survival (OS) and progression-free survival (PFS). Additionally, we examined various secondary factors such as functional outcome via Karnofsky Performance Index (KPS) and prognosis scoring.

RESULTS

157 patients diagnosed with PCNSL or SCNSL were enclosed in the study. Of these, 101 underwent stereotactic biopsy, 21 had open biopsy, and 35 underwent resection. Mean age of the cohort was 64.94 years, with majority of patients being female (54.1%). The resection group showed longest OS at 44 months (open biopsy = 13 months, stereotactic biopsy = 9 months). Calculated median follow-up was 34.5 months. In the Cox regression model, postoperative KPS 70% (p < 0.001) and resection vs. stereotactic biopsy (p = 0.040) were identified as protective factors, whereas older age at diagnosis was identified as a risk factor (p < 0.001). In the one-way analysis of variance, differences in postoperative KPS were found among all groups (p = 0.021), while there was no difference in preoperative KPS among the groups.

CONCLUSIONS

Our data show a favourable outcome when resection is compared to either stereotactic or open biopsy. Additionally, the marginally improved postoperative functional status observed in patients who underwent resection, as opposed to in those who underwent biopsy, provides further evidence in favour of the advantages of surgical resection for enhancing neurological deficits.

Evidence-based management of primary and secondary CNS lymphoma

Central nervous system (CNS) lymphoma has traditionally had very poor outcomes however advances in management have resulted in dramatic improvements and long-term survival of patients. We describe the evidence for treatment strategies for these aggressive disorders. In primary CNS lymphoma there are randomized trial data to inform treatment decisions but these are lacking to guide management in secondary CNS lymphoma. Dynamic assessment of patient fitness and frailty is key throughout treatment, alongside delivery of CNS-bioavailable therapy and enrolment in clinical trials, at each stage of the disease. Intensive high-dose methotrexate-containing induction followed by consolidation with autologous stem cell transplantation with thiotepa-based conditioning is recommended for patients who are fit. Less intensive chemoimmunotherapy, novel agents (including Bruton tyrosine kinase inhibitors, cereblon targeting immunomodulatory agents, and checkpoint inhibitors in the context of clinical trials), and whole brain radiotherapy may be reserved for less fit patients or disease which is chemoresistant. Data regarding the efficacy of chimeric antigen receptor T-cells therapy is emerging, and concerns regarding greater toxicity have not been realized. Future areas of prospective studies include the identification of those at high risk of developing CNS lymphoma, management in elderly or frail patients as well as incorporating novel agents into regimens, particularly for those with chemoresistant disease.

Impact of thiotepa dose-intensity in primary diffuse large B-cell lymphoma of the central nervous system undergoing autologous hematopoietic cell transplant with thiotepa/carmustine conditioning

Thiotepa/carmustine (TT-BCNU) is a commonly used autologous transplant (ASCT) conditioning regimen for primary DLBCL of the CNS (PCNSL). The total thiotepa dose varies among TT-BCNU recipients, with some centers administering a total dose of 20 mg/kg, while others using 10 mg/kg. We retrospectively assessed the impact of thiotepa dose intensity on ASCT outcomes in 218 adult PCNSL patients who underwent a first ASCT with TT-BCNU conditioning and received either a total thiotepa dose of 10 mg/kg (TT-10 group; N = 90), or 20 mg/kg (TT-20 group; N = 128). The median follow-up of survivors was 22 months. The cumulative incidence of 1-year non-relapse mortality (NRM) for TT-10 and TT-20 cohorts were 6% (95%CI = 2-12%) vs. 4% (95%CI = 1-8%), respectively (p = 0.66). The 3-year cumulative incidence of relapse (15% vs. 13%; p = 0.67), progression-free survival (PFS) (71% vs. 80%; p = 0.25) and overall survival (OS) (79% vs. 83%; p = 0.56) were similar in the TT-10 and TT-20 groups, respectively. On multivariate analysis compared to TT-10, the TT-20 cohort was not associated with significantly different risk of NRM (Hazard ration [HR] = 0.77; p = 0.64), relapse/progression (HR = 0.87; p = 0.74), PFS (HR = 0.80; p = 0.48) or OS (HR = 1.10; p = 0.80). In conclusion thiotepa dose-intensity in TT-BCNU conditioning does not impact ASCT outcomes of PCNSL patients.

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.

Immunochemotherapy or chemotherapy alone in primary central nervous system lymphoma: a National Cancer Database analysis

Debate remains over the role of rituximab, a large molecule with reduced central nervous system (CNS) penetration, in therapy for primary CNS lymphoma (PCNSL). Since 2013, the National Cancer Database has distinguished between chemotherapy and immunotherapy for frontline treatment. In this setting, rituximab would be the only standard frontline immunotherapy. We examined factors associated with the receipt of immunotherapy using a multivariate regression model for relative risk, with a random intercept to account for the hospital-specific treatment selection process. Patients were matched using a 1:1 propensity score to limit possible confounders, and overall survival (OS) was compared in the matched cohort. We identified 4691 patients with PCNSL diagnosed between 2013 and 2018. The use of immunotherapy has increased from 45% in 2013 to 76% in 2018. Immunotherapy use was associated with sociodemographic variables and local (hospital level) preference rather than clinical factors. The main factors associated with reduced use of immunotherapy included male sex, Black race or Hispanic ethnicity (compared with White non-Hispanic), HIV+ status, treatment in a lower-volume hospital, and earlier year of diagnosis. We matched 2830 patients for the survival analysis. Receipt of immunotherapy was associated with a significantly better OS (hazard ratio [HR], 0.75; 95% confidence interval [CI], 0.67-0.83). There was heterogeneity according to age, because the advantage of immunotherapy was more pronounced for patients aged ≤75 years (HR, 0.71; 95% CI, 0.63-0.80) than for those older than 75 years (HR, 0.87; 95% CI, 0.70-1.08). Overall, our findings support the current trend toward rituximab use, although a nuanced approach should be adopted when treating older patients.

Primary central nervous system lymphoma (PCNSL) in older patients

INTRODUCTION

Primary central nervous system lymphoma (PCNSL) is a rare, chemo and radio-sensitive tumor limited to the central nervous system. The incidence of PCSNL increases notably in the elderly population which represented approximately half of the patients. The limit of 'elderly' population remained debated and nonuniform, including 60 years as a cutoff for brain radiotherapy, 65 years for autologous stem-cell transplantation, and 70 years for the last clinical trials. Current therapeutic options include first line treatment based on high-dose methotrexate based polychemotherapy, consolidation chemotherapy, and adapted autologous stem cell transplantation for highly selected patients. At relapse, single agent targeted therapies or salvage chemotherapy followed by intensive consolidation are promising therapeutic options. Nevertheless, improving management of elderly patients is an urgent medical need that currently remains unresolved.

OBJECTIVE

We will focus on elderly patients with PCNSL and their specificities including clinical presentations, available therapeutic options and adaptations to be made.

CONCLUSION

To improve survival, it will be necessary to personalized and adapt the treatments, to each patient and his comorbidities, to increase their effectiveness and limit their toxicity in this frail population. Finally, inclusion of these patients in clinical trials is one of the major challenges to significantly change PCNSL elderly patient prognosis.

New hopes in relapsed refractory primary central nervous system lymphoma

PURPOSE OF REVIEW

Patients with relapsed/refractory primary central nervous system lymphoma (rrPCNSL) have poor prognosis, with a median survival after relapse of 6.8 months. In this review, we discuss the evolving landscape and the possible future directions related to this important unmet clinical need.

RECENT FINDINGS

The modern two-phase approach for newly diagnosed PCNSL based on an induction using high-dose methotrexate (HD-MTX) combinations and a subsequent consolidation, has significantly improved the outcome in this setting. However, this strategy is able to cure more or less 50% of patients. rrPCNSL patients have a very poor prognosis with a reported 5-year overall survival of 18%. Late relapses (after third year) and use of high-dose chemotherapy and autologous stem cell transplantation (HDT-ASCT) represent important factors associated with a better outcome in this setting. On the basis of the growing acquisition of knowledge on the molecular characteristics of PCNSL, the use of non-chemotherapeutic drugs such as bruton tyrosine kinase inhibitors (BTK-is), immunomodulatory drugs (IMiDs) and immune checkpoint blockers (ICBs) is increasing in the last years along with the introduction of novel approaches (CAR-T cells and blood--brain barrier disruption). However, despite high responses in some cases, durations are often short, translating in outcome results still unsatisfactory.

SUMMARY

Treatment of rrPCNSL patients is challenging. As no standard of care exist in this setting, it is of paramount importance to acquire new knowledge related to this condition and start multidisciplinary collaboration in order to improve pts outcome.

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.

Multiply Relapsed Secondary CNS Non-Germinal Center Diffuse Large B-Cell Lymphoma Successfully Treated with CNS-Centric Therapy

Secondary central nervous system involvement by systemic diffuse large B-cell lymphoma (DLBCL) carries a very poor prognosis. We present a female patient who had two episodes of intracerebral central nervous system (CNS)-only relapse of systemic non-germinal center diffuse large B-cell lymphoma (NGC-DLBCL). Her treatment at initial diagnosis consisted of induction with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) and intrathecal (IT) - methotrexate (MTX) followed by consolidation with autologous stem cell transplant (ASCT) after high-dose carmustine, etoposide, cytarabine, and melphalan (BEAM) chemotherapy. She had the first CNS-only relapse 1.5 years post-ASCT and received whole brain radiation therapy (WBRT). She developed the second intracerebral CNS-only relapse 2 years post-WBRT. A CNS-centric therapeutic approach with salvage chemoimmunotherapy incorporating rituximab, high-dose methotrexate (HD-MTX), high-dose cytarabine (HiDAC), and ibrutinib was utilized for her second CNS-only relapse. She underwent consolidation with a second ASCT following high-dose carmustine (BCNU) and thiotepa chemotherapy. Given her high risk of CNS recurrence, she was started on maintenance ibrutinib. To date, she has remained in complete remission for 3 years. In our experience, multiply relapsed secondary CNS lymphoma (SCNSL) with this response is very rare. We suggest one CNS-centric therapeutic approach that can potentially salvage patients with SCNSL who have not had prior exposure to adequate CNS-directed therapies but acknowledge that additional research is necessary to validate our findings.

Long-Term Results with Thiotepa-Containing Conditioning Regimens for Autologous Stem Cell Transplantation

Autologous stem cell transplantation (ASCT) remains a cornerstone in the treatment of both Hodgkin lymphoma (HL) and various non-Hodgkin lymphoma (NHL) subtypes. BEAM (carmustine, etoposide, cytarabine, and melphalan) is the most frequently used conditioning regimen; however, owing due to limited availability and toxicity of carmustine, thiotepa-containing regimens have been suggested. We previously reported encouraging results in ASCT with a TECAM (thiotepa, etoposide, cyclophosphamide, cytarabine, and melphalan) conditioning regimen from 2000 to 2013. We aimed to update our experience with the TECAM regimen by adding our experience from 2013 to 2020 to the previously reported cohort. Moreover, we aimed to use the detailed data for the 2 transplant cohorts to identify improvements in ASCT outcomes in the recent era. We retrospectively analyzed all lymphoma patients who underwent ASCT at our center between January 2000 and December 2020. A total of 353 lymphoma patients were included (142 in the newer cohort added to 211 previously reported patients), all of whom were treated with our standard TECAM conditioning regimen. The cohort included 127 patients with HL, 107 with DLBCL, and 119 with other NHL subtypes. The newer cohort was characterized by significantly poorer Eastern Cooperative Oncology Group Performance Status (ECOG-PS) prior to ASCT (45.7% versus 19.3% with ECOG-PS ≥1; P < .01), whereas a higher proportion of patients entered transplantation in complete response (CR) (71.9% versus 47.8%; P < .01). The median follow-up after ASCT was 136.4 months (95% confidence interval [CI], 91.4 to 181.4 months). The 3-year progression-free survival (PFS) and overall survival (OS) rates post-ASCT for the entire cohort were 59.8% and 79.3%, respectively. Evaluating the 303 of 353 patients (86.4%) who entered ASCT with a responsive disease-a population that represents today's approach to the selection of patients for ASCT-the 3-year PFS and OS rates were 61.5% and 81.9%, respectively. In this population, the 3-year PFS rate was 62.2% for HL, 62.6% for DLBCL, 64.3% for primary central nervous system lymphoma (PCNSL), and the 3-year OS rate were 90.1%, 75.2%, and 78.6%, respectively. OS was significantly better in the newer cohort (P < .01), but not when evaluating only patients who entered ASCT with responsive disease. Dose reductions, poor disease status, and poor ECOG-PS at ASCT entry were associated with worse outcomes across all lymphoma subtypes. In accordance with our previous report, patients entering transplantation for DLBCL with a partial response achieved similar outcomes as those with a CR. Eighteen patients died within the first 100 days, 8 due to disease progression and 10 due to transplantation-related complications (2.8%). There were no cases of interstitial pneumonitis syndrome. Twenty-two cases (6.2%) of secondary malignancies were documented. Our results confirm that TECAM is an effective and safe conditioning regimen for ASCT in patients with HL and various NHLs, including favorable results in PCNSL. Despite a higher proportion of frail patients, the newer cohort's outcomes were favorable, driven by better lymphoma control pretransplantation. In the DLBCL cohort, ECOG-PS had more prognostic value than achieving a CR pre-ASCT, a finding relevant to the optimal allocation of patients to different treatment options in the era of chimeric antigen receptor T cell availability.

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.

Primary central nervous system lymphoma

Primary central nervous system lymphoma (PCNSL) is a diffuse large B cell lymphoma in which the brain, spinal cord, leptomeninges and/or eyes are exclusive sites of disease. Pathophysiology is incompletely understood, although a central role seems to comprise immunoglobulins binding to self-proteins expressed in the central nervous system (CNS) and alterations of genes involved in B cell receptor, Toll-like receptor and NF-κB signalling. Other factors such as T cells, macrophages or microglia, endothelial cells, chemokines, and interleukins, probably also have important roles. Clinical presentation varies depending on the involved regions of the CNS. Standard of care includes methotrexate-based polychemotherapy followed by age-tailored thiotepa-based conditioned autologous stem cell transplantation and, in patients unsuitable for such treatment, consolidation with whole-brain radiotherapy or single-drug maintenance. Personalized treatment, primary radiotherapy and only supportive care should be considered in unfit, frail patients. Despite available treatments, 15-25% of patients do not respond to chemotherapy and 25-50% relapse after initial response. Relapse rates are higher in older patients, although the prognosis of patients experiencing relapse is poor independent of age. Further research is needed to identify diagnostic biomarkers, treatments with higher efficacy and less neurotoxicity, strategies to improve the penetration of drugs into the CNS, and roles of other therapies such as immunotherapies and adoptive cell therapies.

Clinicopathological analysis and specific discriminating markers of interleukin detection in cerebrospinal fluid with primary central nervous system lymphoma: results from a retrospective study

Primary central nervous system lymphoma (PCNSL) is special extranodal malignant non-Hodgkin lymphomas. This study analyzed clinical features and prognostic factors of PCNSL and evaluated the difference of interleukin (IL) concentrations in cerebrospinal fluid (CSF) between PCNSL and systemic non-Hodgkin lymphoma (sNHL). Patients consecutive newly diagnosed with PCNSL were recruited, the demographic and clinicopathological data were retrospectively analyzed, and the potential prognostic factors for overall survival (OS) were identified with survival analysis. 27 patients with PCNSL and 21 patients with sNHL collected CSF IL-5, IL-6, and IL-10 concentrations at diagnosis. The difference in interleukin (IL) concentrations in two diseases was analyzed to evaluate the value of IL concentrations. A total of 64 patients with PCNSL were enrolled, the median age was 54.50 years (range 16-85 years); male: female ratio was 1.91. Headache was the most common complaint symptom involved in 42.19% (27/64) of patients. Diffuse large B-cell lymphoma (DLBCL) accounted for 89.06% (57/64) of patients; other uncommon types accounted for 3.13% (2/64). In prognostic analysis, multiple lesions and Ki67 ≥ 75% expression exhibited a worse prognosis(P = 0.041), and patients with autologous hematopoietic stem cell transplantation (auto-HSCT) treatment presented superior OS (P < 0.05). In multivariate analysis, BCL2 expression was revealed as an unfavorable prognostic marker, and auto-HSCT was revealed as a favorable prognostic marker. CSF IL-10 concentration in patients with PCNSL was significantly higher than sNHL (P = 0.000) and excluded other histopathology of NHL; IL-10 value was still significantly different between DLBCL of PCNSL and sDLBCL (P = 0.003). In ROC curve analysis, the cutoff value of IL-10 was 0.43 pg/mL for the diagnosis value of PCNSL, sensitivity was 96.3%, specificity was 66.67%, and AUC was 0.84 (0.71-0.96). Although IL-6 concentration did not differ in the two groups, IL-10/IL-6 ratio was meaningful, with a cutoff value of 0.21, sensitivity of 81.48%, specificity of 80.95%, and AUC of 0.83 (0.71-0.95). This study highlights the characteristics of patients with PCNSL, potential prognostic makers also have been explained. CSF interleukin (IL) concentrations revealed IL-10 levels, and IL-10/IL-6 ratio may represent a useful biomarker in the differential diagnosis of PCNSL and sNHL.

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.

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.

Long term outcomes in older patients with primary central nervous system lymphoma: an analysis of the Texas Cancer Registry

Primary central nervous system lymphoma (PCNSL) is an aggressive subtype of non-Hodgkin lymphoma that carries a poor prognosis in the elderly. The aim of this study is to investigate treatment patterns and survival trends in patients ≥ 65 years with PCNSL through data provided by the Texas Cancer Registry. Adults ≥ 65 years diagnosed with PCNSL and followed between 1995-2017 were identified and separated into three eras: 1995-2003, 2004-2012, and 2013-2017. Baseline covariates compared included patient demographics and treatments administered. Pearson's chi-squared test and Cox proportional hazard models compared covariates; overall survival (OS) and disease-specific survival (DSS) were assessed via Kaplan-Meier methodology. There were 375 patients; 104 (27.7%) in 1995-2003, 146 (38.9%) in 2004-2012, and 125 (33.3%) in 2013-2017. There were 50 (48.1%), 55 (37.7%), and 31 (24.8%) in 1995-2003, 2004-2012, and 2013-2017, respectively, that did not receive treatment. At last follow up, 101 (97.1%), 130 (89.0%), and 94 (75.2%) in each era died, of which 89 (85.6%), 112 (76.7%), and 70 (56.0%) were attributed to PCNSL. Median OS per era was eight (95% confidence interval [CI] 5.06-10.93), six (95% CI, 2.30-9.69), and five months (95% CI, 2.26-7.73) (p = 0.638). DSS per era was nine (95% CI: 0.00, 26.53), 10 (95% CI: 5.14, 14.86), and 19 (95% CI, 0.00-45.49) (p = 0.931) months. Spinal cord as primary disease site (HR: 0.668 [95% CI, 0.45-0.99], p = 0.049), and chemotherapy (HR 0.532 [95% CI, 0.42-0.673], p =  < 0.001) or chemotherapy + radiation (HR, 0.233 [95% CI, 0.11-0.48] p < 0.001) had better outcomes compared to no therapy or radiation therapy alone. Survival in older patients ≥ 65 with PCNSL has not improved per our analysis of the TCR from 1995-2017 despite increasing trends of treatment utilization. Strategies to augment recruitment of older individuals in trials are needed in order to determine who would derive treatment benefit and minimize treatment toxicities.

Prevention and management of secondary central nervous system lymphoma

Secondary central nervous system (CNS) lymphoma (SCNSL) is defined by the involvement of the CNS, either at the time of initial diagnosis of systemic lymphoma or in the setting of relapse, and can be either isolated or with synchronous systemic disease. The risk of CNS involvement in patients with diffuse large B-cell lymphoma is approximately 5%; however, certain clinical and biological features have been associated with a risk of up to 15%. There has been growing interest in improving the definition of patients at increased risk of CNS relapse, as well as identifying effective prophylactic strategies to prevent it. SCNSL often occurs within months of the initial diagnosis of lymphoma, suggesting the presence of occult disease at diagnosis in many cases. The differing presentations of SCNSL create the therapeutic challenge of controlling both the systemic disease and the CNS disease, which uniquely requires agents that penetrate the blood-brain barrier. Outcomes are generally poor with a median overall survival of approximately 6 months in retrospective series, particularly in those patients presenting with SCNSL after prior therapy. Prospective studies of intensive chemotherapy regimens containing high-dose methotrexate, followed by hematopoietic stem cell transplantation have shown the most favorable outcomes, especially for patients receiving thiotepa-based conditioning regimens. However, a proportion of patients will not respond to induction therapies or will subsequently relapse, indicating the need for more effective treatment strategies. In this review we focus on the identification of high-risk patients, prophylactic strategies and recent treatment approaches for SCNSL. The incorporation of novel agents in immunochemotherapy deserves further study in prospective trials.

Primary central nervous system lymphoma: a practical guide for neurologists

Primary central nervous system lymphoma is rare, comprising 4% of intracranial neoplasms. Although haematologists or oncologists subsequently manage the condition, it is often neurologists who first make, or at least suspect, the diagnosis. This article reviews the disease, its clinical and radiological features and details the work-up needed to achieve a diagnosis (namely histological or cytological confirmation) and to prepare the patient for treatment. We note the importance of brain biopsy, the role of corticosteroids and the varied treatment options.

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.

Patient Reported and Clinical Outcomes after High-Dose Chemotherapy and Autologous Stem Cell Transplantation in Primary Central Nervous System Lymphoma

Primary central nervous system lymphomas (PCNSL) are rare and associated with an adverse prognosis. High-dose chemotherapy followed by autologous stem cell transplantation (HDC/ASCT) improves progression free (PFS) and overall survival (OS) but neurocognition, performance status and quality of life (QoL) in patient-reported outcome (PRO) after HDC/ASCT remains underexplored. Especially elderly patients may insufficiently recover from this demanding therapy. Therefore, this single-center analysis investigated all PCNSL patients who received HDC/ASCT at the University Hospital Tübingen from 2006-2021 (n = 40, median age 60.5 years) in a retrospective manner. The 2-year PFS/OS was 78.7%/77.3%, respectively, without significant differences between the tested age-groups (≤60 vs. >60 years, p = 0.531/p = 0.334). Higher Thiotepa dosage was an independent predictor for better OS (p = 0.018). Additionally, a one-time prospective, cross-sectional analysis after HDC/ASCT in the same cohort was performed (n = 31; median follow-up 45 months). Here, the median ECOG improved by HDC/ASCT from 1 to 0 and mini-mental state examinations revealed unimpaired neurocognitive functioning (median 28 pts.). PRO data collected by EORTC QLQ-C30 showed a good QoL in both age groups with an average global health status (GHS) of 68.82% (≤60y: 64.72%, >60y: 74.14%). Together, our data indicate that HDC/ASCT is an effective therapy with respect to disease control, overall health status and quality of life, irrespective of patient age.

Diagnosis and Treatment Using Autologous Stem-Cell Transplantation in Primary Central Nervous System Lymphoma: A Systematic Review

BACKGROUND

Consolidation therapy has improved the outcome of newly diagnosed PCNSL patients. Whole-brain radiotherapy (WBRT) was the first consolidation strategy used and represented the gold standard for many years, but at the expense of a high risk of neurotoxicity. Thus, alternative strategies are being investigated in order to improve disease outcomes and to spare the neurocognitive side effects due to WBRT.

METHODS

We reviewed published studies on PCNSL patients treated with HDC/ASCT, focusing on the efficacy and safety of the conditioning regimens. Prospective and retrospective studies, published in the English language from 1992 to 2022, in high-quality international journals were identified in PubMed.

RESULTS

Consolidation with HDC containing highly CNS-penetrating agents (thiotepa, busulfan or BCNU) followed by ASCT provided long-term disease control and survival in PCNSL patients. Two prospective randomized studies, comparing HDC/ASCT versus WBRT, reported similar progression-free survival (PFS) and similar results on the decline in neurocognitive functions in a substantial proportion of patients after WBRT but not after HDC-ASCT. A recent randomized study comparing HDC/ASCT versus non-myeloablative consolidation reported a longer PFS in transplanted patients.

CONCLUSION

ASCT conditioned with regimens, including highly CNS-penetrating agents, represents, to date, the best choice among the available consolidation strategies for fit newly diagnosed PCNSL patients.

European Association of Neuro-Oncology (EANO) guidelines for treatment of primary central nervous system lymphoma (PCNSL)

The management of primary central nervous system (PCNSL) is one of the most controversial topics in neuro-oncology because of the complexity of the disease and the limited number of controlled studies available. In 2021, given recent advances and the publication of practice-changing randomized trials, the European Association of Neuro-Oncology (EANO) created a multidisciplinary task force to update the previously published evidence-based guidelines for immunocompetent adult patients with PCNSL and added a section on immunosuppressed patients. The guideline provides consensus considerations and recommendations for the treatment of PCNSL, including intraocular manifestations and specific management of the elderly. The main changes from the previous guideline include strengthened evidence for the consolidation with ASCT in first-line treatment, prospectively assessed chemotherapy combinations for both young and elderly patients, clarification of the role of rituximab even though the data remain inconclusive, of the role of new agents, and the incorporation of immunosuppressed patients and primary ocular lymphoma. The guideline should aid the clinicians in everyday practice and decision making and serve as a basis for future research in the field.

Characteristics and outcomes of patients undergoing high-dose chemotherapy and autologous stem cell transplantation admitted to the intensive care unit: a single-center retrospective analysis

High-dose chemotherapy and autologous stem cell transplantation (ASCT) can be associated with adverse events necessitating treatment on the intensive care unit (ICU). Data focusing on patients admitted to the ICU during hospitalization for high-dose chemotherapy and ASCT are scarce. We thus conducted a single-center retrospective analysis comprising 79 individuals who had high-dose chemotherapy and ASCT between 2014 and 2020 and were admitted to the ICU between the initiation of conditioning therapy and day 30 after ASCT. The median age was 57 years (range: 20-82 years); 38% of patients were female. B-cell non-Hodgkin lymphoma (34%) and plasma cell disorders (28%) were the most common indications for high-dose chemotherapy and ASCT. Sepsis represented the major cause for ICU admission (68%). Twenty-nine percent of patients required mechanical ventilation (MV), 5% had renal replacement therapy, and 44% needed vasopressors. The ICU, hospital, 90-day, and 1-year survival rates were 77.2%, 77.2%, 72.2%, and 60.3%, respectively. Stable disease or disease progression prior to the initiation of high-dose chemotherapy (p = 0.0028) and MV (p < 0.0001) were associated with an impaired survival. A total of 36 patients died during observation. The most frequent causes of death were the underlying malignancy (44%) and sepsis (39%). Taken together, the present analysis indicates a favorable overall outcome for patients admitted to the ICU during hospitalization for high-dose chemotherapy and ASCT. Thus, this patient group should not be denied admission and treatment on the ICU.

The role of radiotherapy in newly diagnosed primary CNS lymphoma: A descriptive review and a pragmatic approach to clinical practice

Earlier, prior to the development of effective systemic therapy, monotherapy with whole-brain radiotherapy (WBRT) was widely used to treat primary central nervous system lymphoma (PCNSL). Recently, chemotherapy, especially with high dose methotrexate (HDMTX), has largely replaced WBRT as upfront treatment, and the most accepted standard of care is induction with a combination drug therapy followed by consolidation therapy with either autologous stem-cell transplantation (ASCT) or radiation. Whilst WBRT is an effective component of treatment, it is occasionally associated with risk of permanent, irreversible neurotoxicity when doses of more than 30 Gy are used. Hence, there has been a strong focus on the optimization of radiotherapy (RT) which includes dose reduction in the consolidation phase. In this comprehensive review, we have summarized the progress on clinical results and evidence considering the role and use of radiation including combined treatment modalities, low-dose radiotherapy, and neurotoxicity. Finally, we present a practical approach to low-dose WBRT and boosting higher doses to the gross tumor that can be integrated into clinical practice.

Surgical resection versus biopsy in the treatment of primary central nervous system lymphoma: a systematic review and meta-analysis

PURPOSE

Despite the improvement in treatment and prognosis of primary central nervous system lymphoma (PCNSL) over the last decades, the 5-year survival rate is approximately 30%; thus, new therapeutic approaches are needed to improve patient survival. The study's aim was to evaluate the role of surgical resection of PCNSL.

METHODS

Primary outcomes were the overall survival (OS) and progression-free survival (PFS) of patients with PCNSL who underwent surgical resection versus biopsy alone. The meta-analysis was conducted to calculate pooled hazard ratios (HRs) under a random-effects model for the time-to-event variables. The odds ratios (ORs) were calculated for binary, secondary outcome parameters.

RESULTS

Seven studies (n = 1046) were included. We found that surgical resection was associated with significantly better OS (HR 0.63 [95% CI 0.51-0.77]) when compared with biopsy. PFS was also significantly improved (HR 0.64 [95% CI 0.49-0.85]) in patients who underwent resection compared with those who underwent biopsy. The heterogeneity for OS and PFS was low (I2 = 7% and 24%, respectively). We also found that patients who underwent biopsy more often had multiple (OR 0.38 [95% CI 0.19-0.79]) or deep-seated (OR 0.20 [95% CI 0.12-0.34]) lesions compared with those who underwent surgical resection. There were no significant differences in chemotherapy or radiotherapy use or the occurrence of postoperative complications between the two groups.

CONCLUSION

In selected patients, surgical resection of PCNSL is associated with significantly better overall survival and progression-free survival compared with biopsy alone.

Primary CNS Lymphoma: Progress With Dose-Intensive Consolidation

The Oncology Grand Rounds series is designed to place original reports published in the Journal into clinical context. A case presentation is followed by a description of diagnostic and management challenges, a review of the relevant literature, and a summary of the authors' suggested management approaches. The goal of this series is to help readers better understand how to apply the results of key studies, including those published in Journal of Clinical Oncology, to patients seen in their own clinical practice.

Treatment Options for Recurrent Primary CNS Lymphoma

OPINION STATEMENT

Primary CNS lymphoma (PCNSL) constitutes a rare extranodal variant of non-Hodgkin lymphoma (NHL) with an annual incidence of 0.45/100,000. Given the paucity of large prospective clinical trials, there is no consensus treatment for refractory or relapsed (r/r) PCNSL, and available strategies are largely based on retrospective analyses. Patient age, performance status, previously administered treatment, duration of response, and molecular characteristics guide selection of salvage therapy. Patients with a good performance status (KPS >70), particularly ≤65 years, and adequate organ function should be considered for salvage polychemotherapy. Based on its high overall response rate even in the relapsed setting, we choose high-dose (≥ 3.5g/m²) methotrexate (HD-MTX) based regimens, e.g., R-MPV (rituximab, HD-MTX, procarbazine, and vincristine), for remission re-induction as long as patients were sensitive to first line HD-MTX-based regimens, especially when duration of previous response was ≥ 1 year. Following successful remission induction, we choose myeloablative chemotherapy (e.g., thiotepa, busulfan, cyclophosphamide) and subsequent autologous stem cell transplant in curative intent whenever feasible. Alternatively, conventional chemotherapy regimens (for example, monthly HD-MTX) or low-dose whole-brain radiation therapy (WBRT) are selected for consolidation in non-transplant candidates in complete remission. In cases of HD-MTX refractory disease or contraindications, we use pemetrexed; temozolomide/rituximab; high-dose cytarabine; or whole brain radiation for remission induction. Clinical trial participation is considered as well. Emerging therapies for upfront or salvage therapy under ongoing investigation include bruton tyrosine kinase inhibition (e.g., ibrutinib), immunomodulatory drugs (e.g., lenalidomide), immune checkpoint inhibitors (ICI, e.g., nivolumab), and chimeric antigen receptor T (CAR-T) cell therapy.

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.