First-line autologous stem cell transplantation in primary CNS 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.

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.

Ibrutinib Monotherapy as Bridge-to-Transplant for Relapsed/Refractory Primary Oculo-Cerebral Lymphoma

Introduction. Primary central nervous system lymphoma is an uncommon form of extranodal non-Hodgkin’s lymphoma, with increasing incidence, a relatively aggressive course and a poor 5-year survival. Because of its localization, the therapeutic compounds used in this disease must be able to pass through the blood-brain barrier. Chemotherapy regimens based on high-dose methotrexate are currently the standard of care for all patients who can tolerate such drugs. Autologous stem cell transplantation is indicated for malignant lymphomas in the relapsed/refractory setting. Methods. Three patients, with a median age of 60 years, range 53–64, were diagnosed with primary CNS lymphoma, and treated with ibrutinib monotherapy in the Department of Hematology, Ion Chiricuta Clinical Cancer Center, Cluj-Napoca, Romania, between September 2018 and November 2020 All the patients were relapsed–refractory following high-dose methotrexate chemotherapy. We present our experience using ibrutinib monotherapy-based treatment as a bridge-to-transplant option on a single-center case series and a review of the literature in this field. Results. Two of the patients were given ibrutinib as a second line therapy, both achieving complete remission and being eligible for an autologous stem cell transplantation. The third patient achieved a short remission using six cycles of systemic chemotherapy, but was started on ibrutinib monotherapy, with limited results. Conclusion. Our data is limited, and these results should be confirmed by multicentric clinical trials and should be regarded as a single-center case series, with all its limitations. Still, it brings forward a new therapeutic option for this rare subtype of malignant lymphomas, which if left untreated has a dismal prognosis.

Durable Survival Outcomes in Primary and Secondary Central Nervous System Lymphoma After High-dose Chemotherapy and Autologous Stem Cell Transplantation Using a Thiotepa, Busulfan, and Cyclophosphamide Conditioning Regimen

BACKGROUND

High-dose chemotherapy (HDC) with autologous stem cell transplantation (ASCT) has been investigated in patients with primary central nervous system lymphoma (PCNSL) and non-Hodgkin lymphoma (NHL) with CNS involvement and has shown promising results.

PATIENTS AND METHODS

A retrospective analysis was performed of 48 consecutive patients who had undergone HDC/ASCT with TBC (thiotepa, busulfan, cyclophosphamide) conditioning for PCNSL (27 patients), secondary CNS lymphoma (SCNSL) (8 patients), or relapsed disease with CNS involvement (13 patients) from July 2006 to December 2017. Of the 27 patients with PCNSL, 21 had undergone ASCT at first complete remission (CR1).

RESULTS

The 2-year progression-free survival (PFS) rate was 80.5% (95% confidence interval [CI], 69.9-92.9) and the 2-year overall survival (OS) rate was 80.1% (95% CI, 69.2%-92.7%) among all patients. The 2-year PFS and OS rate for patients with PCNSL in CR1 was 95.2% (95% CI, 86.6%-100%) and 95.2% (95% CI, 86.6%-100%), respectively. On univariate analysis of the patients with PCNSL, ASCT in CR1 was the only variable statistically significant for outcome (P = .007 for PFS; P = .008 for OS). Among patients with SCNSL or CNS relapse, the 2-year PFS and OS rate were comparable at 75.9% (95% CI, 59.5%-96.8%) and 75.3% (95% CI, 58.6%-98.6%), respectively. The most common side effects were febrile neutropenia (89.6%; of which 66.7% had an infectious etiology identified), nausea/vomiting (85.4%), diarrhea (93.8%), mucositis (89.6%), and electrolyte abnormalities (89.6%). Four patients (8.3%) died of treatment-related overwhelming infection; of these patients, 3 had SCNSL.

CONCLUSION

HDC and ASCT using TBC conditioning for both PCNSL and secondary CNS NHL appears to have encouraging long-term efficacy with manageable side effects.

Hematopoietic stem cell transplantation in primary central nervous system lymphoma: a review of the literature

Primary central nervous system lymphoma (PCNSL) is an uncommon variant of extranodal non-Hodgkin lymphoma (NHL) with an aggressive course and worse outcomes compared with other lymphomas of similar tumor burden and histologic subtype. High-dose chemotherapy supported by autologous stem cell transplantation (HDC/ASCT) is an option for therapy for this disease in both the relapse setting and as post-remission consolidation. Data are currently limited to only several single-arm phase II trials with small sample sizes, but randomized trials are now ongoing. In this review, we discuss the efficacy, feasibility, and toxicity of HDC/ASCT for PCNSL and its role in the treatment of this aggressive malignancy, both in the first-line and relapse settings. We also bring to attention the current data on allogeneic stem cell transplantation (allo-SCT) in PCNSL.

Autologous Stem-Cell Transplantation for Primary Central Nervous System Lymphoma: Systematic Review and Meta-analysis

BACKGROUND

Primary central nervous system lymphoma (PCNSL) is an aggressive form of non-Hodgkin lymphoma. Methotrexate is first-line chemotherapy. Autologous stem-cell transplantation (ASCT) is increasingly used as an alternative consolidative treatment to whole-brain radiotherapy.

METHODS

A systematic search of several databases was conducted up through January 10, 2018. Two investigators independently assessed study eligibility and extracted the data. Studies that reported survival outcomes after ASCT were included.

RESULTS

We screened 1517 references and included 43 studies. ASCT was used as consolidative treatment or as salvage treatment/at relapse. Thiotepa, busulfan, and cyclophosphamide and carmustine/thiotepa were commonly used conditioning regimens. In the consolidation setting, 94% of patients experienced or maintained complete or partial response after ASCT. The rates of overall survival (OS) and progression-free survival (PFS) were 94%, 86%, 82%, and 70% and 79%, 70%, 64%, and 54% after 1, 2, 3, and 5 years, respectively. The overall risk of relapse at 5 years was 24%. In the salvage/relapse settings, 85% of patients experienced or maintained complete response or partial response after ASCT. The rates of OS and PFS were 75%, 63%, 56%, and 54% and 85%, 62%, 59%, and 54% after 1, 2, 3, and 5 years, respectively. The risk of relapse at 5 years was 29%. Subgroup analysis showed that the use of carmustine and thiotepa as a conditioning regimen carried the lowest risk of transplant-related mortality. The thiotepa, busulfan, and cyclophosphamide regimen, on the other hand, showed numerically superior OS and PFS rates.

CONCLUSION

This review provides estimates for response and survival to aid in decision making when considering ASCT for patients with PCNSL.

Management of primary central nervous system lymphoma

A rare tumor, primary central nervous system lymphoma can affect immunocompetent and immunocompromised patients. While sensitive to radiotherapy or chemotherapy crossing the blood-brain barrier, it often recurs. Modern treatment consists of high-dose methotrexate-based induction chemotherapy, often followed by consolidation with either radiotherapy or further chemotherapy. Neurotoxicity is however a concern with radiotherapy, especially for patients older than 60 years. The benefit of the addition of rituximab to chemotherapy is unclear. Targeted therapies and immunotherapy have been effective in some patients and are tested on a larger scale. Survival has improved in the last decade, but remains poor in older patients.

Therapy of primary CNS lymphoma: role of intensity, radiation, and novel agents

Primary central nervous system (CNS) lymphomas represent a subgroup of malignancies with specific characteristics, an aggressive course, and unsatisfactory outcome in contrast with other lymphomas comparable for tumor burden and histological type. Despite the high sensitivity to conventional chemotherapy and radiotherapy, remissions are frequently short lasting. Treatment efficacy is limited by several factors, including the biology and microenvironment of this malignancy and the "protective" effect of the blood-brain barrier, which limits the access of most drugs to the CNS. Patients who survive are at high risk of developing treatment-related toxicity, mainly disabling neurotoxicity, raising the question of how to balance therapy intensification with the control of side effects. Recent therapeutic progress and effective international cooperation have resulted in a significantly improved outcome over the past 2 decades, with a higher proportion of patients receiving treatment with curative intent. Actual front-line therapy consists of high-dose methotrexate-based polychemotherapy. Evidence supporting the addition of an alkylating agent and rituximab is growing, and a recent randomized trial demonstrated that the combination of methotrexate, cytarabine, thiotepa, and rituximab (MATRix regimen) is associated with a significantly better overall survival. Whole-brain irradiation and high-dose chemotherapy supported by autologous stem cell transplantation are 2 effective consolidation strategies in patients with a disease responsive to induction chemotherapy. Different strategies such as alkylating maintenance, conservative radiotherapy, and nonmyeloablative consolidation are being addressed in large randomized trials and a more accurate knowledge of the molecular and biological characteristics of this malignancy are leading to the development of target therapies in refractory/relapsing patients, with the overall aim to incorporate new active agents as part of first-line treatment. The pros and cons of these approaches together with the best candidates for each therapy are outlined in this article.

High-dose chemotherapy with thiotepa, busulfan, and cyclophosphamide and autologous stem cell transplantation for patients with primary central nervous system lymphoma in first complete remission

BACKGROUND

High-dose chemotherapy and autologous stem cell transplantation (HDC-ASCT) is a therapeutic option for patients with primary central nervous system lymphoma (PCNSL). To the authors' knowledge, data are limited regarding its use among patients in first complete remission (CR1) with the CNS-directed conditioning regimen of thiotepa, busulfan, and cyclophosphamide (TBC).

METHODS

A retrospective analysis of patients with PCNSL in CR1 who underwent transplantation using a TBC-based conditioning regimen at 2 academic institutions was performed.

RESULTS

Forty-six consecutive patients who underwent HDC-ASCT while in CR1 were identified. The most common induction regimen was high-dose methotrexate plus temozolomide and rituximab (59%). No patients received whole-brain radiotherapy. A total of 40 patients (87%) received cytarabine before undergoing ASCT as either induction intensification, early consolidation therapy, or mobilization. The median time from diagnosis to transplantation was 6 months (range, 4-15 months). The median age of the patients at the time of transplantation was 59 years (range, 27-69 years). With a median follow-up of 2.7 years after ASCT (range, 6 months-7.5 years), the Kaplan-Meier estimates of 2-year overall survival and progression-free survival were 95% (95% confidence interval [95% CI], 80%-99%) and 92% (95% CI, 77%-97%), respectively. The most common toxicities were severe mucositis (35%) and bacterial infections occurring within 100 days of transplantation (35%). The estimated 2-year nonrecurrence mortality rate was 2.9% (95% CI, 0.2%-13.4%).

CONCLUSIONS

HDC-ASCT with a CNS-directed conditioning regimen such as TBC should be considered for patients with PCNSL who are in CR1 because this approach is associated with encouraging disease control and survival in this select patient population. Cancer 2017;123:3073-79. © 2017 American Cancer Society.

High-dose chemotherapy with autologous haemopoietic stem cell transplantation for newly diagnosed primary CNS lymphoma: a prospective, single-arm, phase 2 trial

BACKGROUND

High-dose methotrexate-based chemotherapy is standard for primary CNS lymphoma, but most patients relapse. High-dose chemotherapy with autologous stem cell transplantation (HCT-ASCT) is supposed to overcome the blood-brain barrier and eliminate residual disease in the CNS. We aimed to investigate the safety and efficacy of HCT-ASCT in patients with newly diagnosed primary CNS lymphoma.

METHODS

In this prospective, single-arm, phase 2 trial, we recruited patients aged 18-65 years with newly diagnosed primary CNS lymphoma and immunocompetence, with no limitation on clinical performance status, from 15 hospitals in Germany. Patients received five courses of intravenous rituximab 375 mg/m(2) (7 days before first high-dose methotrexate course and then every 10 days) and four courses of intravenous high-dose methotrexate 8000 mg/m(2) (every 10 days) and then two courses of intravenous rituximab 375 mg/m(2) (day 1), cytarabine 3 g/m(2) (days 2 and 3), and thiotepa 40 mg/m(2) (day 3). 3 weeks after the last course, patients commenced intravenous HCT-ASCT (rituximab 375 mg/m(2) [day 1], carmustine 400 mg/m(2) [day 2], thiotepa 2 × 5 mg/kg [days 3 and 4], and infusion of stem cells [day 7]), irrespective of response status after induction. We restricted radiotherapy to patients without complete response after HCT-ASCT. The primary endpoint was complete response at day 30 after HCT-ASCT in all registered eligible patients who received at least 1 day of study treatment. This trial is registered at ClinicalTrials.gov, number NCT00647049.

FINDINGS

Between Jan 18, 2007, and May 23, 2011, we recruited 81 patients, of whom two (2%) were excluded, therefore we included 79 (98%) patients in the analysis. All patients started induction treatment; 73 (92%) commenced HCT-ASCT. 61 (77·2% [95% CI 66·1-86·6]) patients achieved a complete response. During induction treatment, the most common grade 3 toxicity was anaemia (37 [47%]) and the most common grade 4 toxicity was thrombocytopenia (50 [63%]). During HCT-ASCT, the most common grade 3 toxicity was fever (50 [68%] of 73) and the most common grade 4 toxicity was leucopenia (68 [93%] of 73). We recorded four (5%) treatment-related deaths (three [4%] during induction and one [1%] 4 weeks after HCT-ASCT).

INTERPRETATION

HCT-ASCT with thiotepa and carmustine is an effective treatment option in young patients with newly diagnosed primary CNS lymphoma, but further comparative studies are needed.

FUNDING

University Hospital Freiburg and Amgen.

The role of autologous stem cell transplantation in primary central nervous system lymphoma

Primary central nervous system lymphoma (PCNSL) treatment includes 2 phases: induction and consolidation. Induction consists of high-dose methotrexate-based polychemotherapy for most patients, with regimen and dose variations according to patient characteristics and country. Several strategies have been proposed for the consolidation phase, with whole-brain irradiation (WBRT) the most common. However, some authorities recommend avoiding WBRT because of its related risk of severe neurotoxicity. The most relevant alternatives to WBRT are high-dose chemotherapy supported by autologous stem cell transplantation (HDC/ASCT) or nonmyeloablative chemotherapy, the former supported by several single-arm phase 2 trials. Moreover, HDC/ASCT is the only strategy that is assessed in comparison with WBRT in ongoing randomized trials. The rationale for using HDC/ASCT in PCNSL patients is based on the fact that the delivery of high doses could achieve therapeutic drug concentrations in the brain and cerebrospinal fluid, and that non-cross-resistant drugs used for conditioning (eg, alkylating agents) could favor elimination of residual chemoresistant lymphoma cells. Worldwide experience with HDC/ASCT is limited to few single-arm phase 2 trials, but overall results are encouraging, mostly when thiotepa-containing conditioning regimens are used, both in newly diagnosed and relapsed patients. However, several questions on efficacy and feasibility of HDC/ASCT, as well as the best candidates for this strategy, the optimal conditioning regimen, the best time for response assessment, and acute and late effects, remain unanswered. In this review, we critically analyze reported studies on HDC/ASCT in PCNSL and discuss its current role and future perspectives in treating this aggressive malignancy.

Concomitant systemic and central nervous system non-Hodgkin lymphoma: the role of consolidation in terms of high dose therapy and autologous stem cell transplantation. A 60-case retrospective study from LYSA and the LOC network

The purpose of our study is to determine the outcome of patients with systemic non-Hodgkin lymphoma presenting with neurologic localization at diagnosis, as well as the impact of consolidation in terms of high-dose therapy followed by autologous stem cell transplantation. Newly diagnosed non-Hodgkin lymphoma patients with concomitant systemic and neurological involvement at diagnosis were included in this study. Sixty patients (37 males; 25 females) were included. Median age was 61 years (23-85 years). Histological subtype was mainly diffuse large B-cell lymphoma (n = 54; 90%). The International prognostic index was over 2 in 41 (72%) patients. Median number of extranodal sites was 2 (range: 1-5). Central nervous system involvement alone was documented in 48 patients. Paravertebral involvement with epidural mass and cord compression and positive cerebrospinal fluid were present in 7 patients. Five patients had both central nervous system and epidural involvement. First-line chemotherapy was mainly anthracycline-based (88%) plus high-dose methotrexate (74%) with or without cytarabine. Consolidation with high-dose therapy followed by autologous stem cell transplantation was performed in 19 patients. For the whole population, overall response rate after induction chemotherapy was 76%. Three-year progression-free survival and overall survival were 42 ± 7% and 44 ± 7%, respectively. For patients under 66 years of age, consolidation strategy using high-dose therapy followed by autologous stem cell transplantation positively impacted 3-year overall survival and progression free survival (P = 0.008) and (P = 0.003), respectively. In multivariate analysis, high-dose therapy had a positive impact on 3-year overall survival and progression-free survival for the whole population as well as for patients under 66 years old in CR after induction therapy (OS [HR=0.22 (0.07-0.67)] and progression-free survival [HR = 0.17 (0.05-0.54)]). In conclusion, non-Hodgkin lymphoma prognosis with concomitant systemic and neurological involvement at diagnosis is poor with a high risk of relapse when treated with conventional chemotherapies alone. This retrospective study supports the feasibility and the potential benefit of a consolidative strategy with high-dose therapy followed by autologous stem cell transplantation in this subset of patients. This strategy and the best intensive chemotherapy regimen remain to be validated in prospective trials.

R-MPV followed by high-dose chemotherapy with TBC and autologous stem-cell transplant for newly diagnosed primary CNS lymphoma

High-dose methotrexate-based chemotherapy is the mainstay of treatment of primary central nervous system lymphoma (PCNSL), but relapses remain frequent. High-dose chemotherapy (HDC) with autologous stem-cell transplant (ASCT) may provide an alternative to address chemoresistance and overcome the blood-brain barrier. In this single-center phase-2 study, newly diagnosed PCNSL patients received 5 to 7 cycles of chemotherapy with rituximab, methotrexate (3.5 g/m(2)), procarbazine, and vincristine (R-MPV). Those with a complete or partial response proceeded with consolidation HDC with thiotepa, cyclophosphamide, and busulfan, followed by ASCT and no radiotherapy. Primary end point was 1-year progression-free survival (PFS), N = 32. Median age was 57, and median Karnofsky performance status 80. Following R-MPV, objective response rate was 97%, and 26 (81%) patients proceeded with HDC-ASCT. Among all patients, median PFS and overall survival (OS) were not reached (median follow-up: 45 months). Two-year PFS was 79% (95% confidence interval [CI], 58-90), with no events observed beyond 2 years. Two-year OS was 81% (95% CI, 63-91). In transplanted patients, 2-year PFS and OS were 81%. There were 3 treatment-related deaths. Prospective neuropsychological evaluations suggested relatively stable cognitive functions posttransplant. In conclusion, this treatment was associated with excellent disease control and survival, an acceptable toxicity profile, and no evidence of neurotoxicity thus far. This trial was registered at www.clinicaltrials.gov as NCT00596154.

Consolidative autologous hematopoietic stem-cell transplantation in first remission for non-Hodgkin lymphoma: current indications and future perspective

The non-Hodgkin lymphomas (NHLs) are a heterogeneous group of diseases with variable clinical outcomes. Autologous hematopoietic stem-cell transplantation (ASCT) as frontline, consolidative therapy has been evaluated based upon histological subtype of NHL. In this review, we summarize the major clinical trials guiding the use of frontline ASCT in NHL. With the constantly changing landscape of upfront therapy and multiple promising novel agents, the ability to conduct randomized trials to evaluate the benefit of consolidative ASCT is not only challenging but may be considered by some an inept utilization of resources. Our recommendation for consolidative ASCT is based on analyzing the current available data.

Phase 2 trial of high-dose rituximab with high-dose cytarabine mobilization therapy and high-dose thiotepa, busulfan, and cyclophosphamide autologous stem cell transplantation in patients with central nervous system involvement by non-Hodgkin lymphoma

BACKGROUND

High-dose thiotepa, busulfan, and cyclophosphamide (TBC) with autologous stem cell transplantation (ASCT) has been used in patients with central nervous system (CNS) involvement by non-Hodgkin lymphoma (NHL). Despite limited penetration into the CNS, rituximab is active in primary CNS NHL. Therefore, high-dose rituximab was combined with TBC for ASCT in patients with CNS NHL.

METHODS

A single-arm phase 2 trial using high-dose rituximab with cytarabine for stem cell mobilization followed by high-dose rituximab combined with thiotepa, busulfan, and cyclophosphamide (R-TBC) for ASCT was conducted. Doses of rituximab at 1000 mg/m(2) were given on days 1 and 8 of mobilization and on days -9 and -2 of TBC. The primary endpoint was efficacy.

RESULTS

Thirty patients were enrolled. Eighteen patients had primary CNS NHL (12 with complete remission (CR)/first partial remission (PR1) and 6 with CR/PR2), and 12 patients had secondary CNS lymphoma (5 with CR/PR1 and 7 with CR/PR2 or beyond). All patients were in partial or complete remission. Twenty-nine patients proceeded to R-TBC ASCT. Two patients developed significant neurotoxicity. The 100-day nonrelapse mortality rate was 0%, and 1 patient died because of nonrelapse causes 5 months after ASCT. For all patients, at a median follow-up of 24 months (range, 12-40 months), the estimated 2-year progression-free survival rate was 81% (95% confidence interval, 59%-92%), and the 2-year overall survival rate was 93% (95% confidence interval, 76%-98%). There were no relapses or deaths among the 18 patients with primary CNS lymphoma.

CONCLUSIONS

For patients with CNS involvement by B-cell NHL and especially for patients with primary CNS NHL, R-TBC ASCT shows encouraging activity and merits further study.

Autologous stem cell transplant in recurrent or refractory primary or secondary central nervous system lymphoma using thiotepa, busulfan and cyclophosphamide

The prognosis for patients with central nervous system (CNS) involvement by recurrent or refractory diffuse large B-cell lymphoma is poor, with overall survival (OS) of 4-10 months. High-dose chemotherapy (HDC) and autologous stem cell transplant (ASCT) is a potential treatment alternative. We reviewed patients with recurrent primary (PCNSL) or secondary (SCNSL) CNS lymphoma referred for consolidation HDC-ASCT utilizing thiotepa, busulfan and cyclophosphamide (TBC). Among the 17 patients included, all had achieved a complete remission after salvage induction chemotherapy, which incorporated methotrexate in 82% of patients. Two patients failed stem-cell harvesting and 15 (88%) underwent transplant. The estimated 3-year progression-free survival (PFS) and OS were both 93% (95% confidence interval 61-99%). Median PFS and OS were not reached. There was no transplant-related mortality. These results confirm the benefit of TBC followed by ASCT in select patients with recurrent PCNSL and suggest a potential role for the regimen in those with SCNSL. Further investigation is warranted.

Diagnosis and treatment of primary CNS lymphoma

Primary CNS lymphoma (PCNSL) is a rare lymphoma that is confined to the CNS, with low tendency for systemic dissemination and a relatively aggressive course. Outcome in patients with PCNSL is often poor. Owing to its low incidence, current knowledge about optimal treatment of PCNSL is fragmentary. Chemotherapy regimens based on high-dose methotrexate are currently standard treatment for all patients with PCNSL who can tolerate such drugs. Whole-brain radiotherapy alone can lead to remission in up to 90% of patients, but often results in poor long-term disease control when given alone, and in delayed neurotoxicity when given after high-dose methotrexate. In this Review, we describe current approaches to diagnosis and treatment of PCNSL, and discuss novel therapeutic approaches that are currently in development, such as the use of rituximab and high-dose chemotherapy followed by autologous stem-cell transplantation. The possible use of intrathecal and intraventricular chemotherapy, optimal salvage treatment, and specific treatment approaches in elderly, paediatric and immunocompromised patients, are also considered.

Rituximab is associated with improved survival for aggressive B cell CNS lymphoma

BACKGROUND

The optimal treatment strategy in patients with aggressive B cell central nervous system lymphoma suitable to receive intensive therapy is unknown. The benefit of incorporating rituximab in systemic therapy remains unclear. We performed a retrospective study examining the impact of rituximab in the context of concomitant therapies, including methotrexate, cytarabine, and radiotherapy, in patients treated with curative intent at 4 university teaching hospitals during 1996-2011.

METHODS

A retrospective study of CNS lymphoma cases treated at the participating institutions was performed in accordance with institutional ethical guidelines. Patients were included if they received a diagnosis of primary diffuse large B cell lymphoma of the CNS, were HIV negative, and were treated with curative intent.

RESULTS

One hundred twenty patients aged 21-81 years were identified. Rituximab recipients and nonrecipients were similar, except for rituximab recipients being more likely to have received a diagnosis after 2004. The median follow-up of surviving patients was 30 months. The 5-year overall survival was 46%. Univariate analysis revealed age ≤60 years, ECOG performance status ≤1, normal lactate dehydrogenase, diagnosis after 2004, and treatment with cytarabine and rituximab as predictive of favorable overall survival. Multivariate analysis identified age to be an independent predictor of overall survival, with a trend toward improved survival from the other variables that were significant in univariate analyses.

CONCLUSIONS

In this retrospective analysis, the addition of rituximab to high-dose methotrexate-based chemotherapy in patients with aggressive B cell CNS lymphoma was associated with improved overall survival. Further studies are underway to prospectively validate these findings.

Salvage chemoimmunotherapy with rituximab, ifosfamide and etoposide (R-IE regimen) in patients with primary CNS lymphoma relapsed or refractory to high-dose methotrexate-based chemotherapy

Despite a high proportion of patients with primary CNS lymphoma (PCNSL) experiences failure after/during first-line treatment, a few studies focused on salvage therapy are available, often with disappointing results. Herein, we report feasibility and activity of a combination of rituximab, ifosfamide and etoposide (R-IE regimen) in a multicentre series of patients with PCNSL relapsed or refractory to high-dose methotrexate-based chemotherapy. We considered consecutive HIV-negative patients ≤75 years old with failed PCNSL treated with R-IE regimen (rituximab 375 mg/m(2) , day 0; ifosfamide 2 g/m(2) /day, days1-3; etoposide 250 mg/m(2) , day 1; four courses). Twenty-two patients (median age 60 years; range 39-72; male/female ratio: 1:4) received R-IE as second-line (n = 18) or third-line (n = 4) treatment. Eleven patients had refractory PCNSL, and 11 had relapsing disease. Twelve patients had been previously irradiated. Sixty (68%) of the 88 planned courses were actually delivered; only one patient interrupted R-IE because of toxicity. Grade 4 hematological toxicity was manageable; a single case of grade 4 non-hematological toxicity (transient hepatotoxicity) was recorded. Response was complete in six patients and partial in three (overall response rate = 41%; 95%CI: 21-61%). Seven patients were successfully referred to autologous peripheral blood stem cell collection; four responders were consolidated with high-dose chemotherapy supported by autologous stem cell transplant. At a median follow-up of 24 months, eight responders did not experience relapse, two of them died of neurological impairment while in remission. Six patients are alive, with a 2-year survival after relapse of 25 ± 9%. We concluded that R-IE is a feasible and active combination for patients with relapsed/refractory PCNSL. This regimen allows stem cell collection and successful consolidation with high-dose chemotherapy and autologous transplant.

Current and emerging pharmacotherapies for primary CNS lymphoma

Primary central nervous system lymphoma (PCNSL) constitutes a rare group of extranodal non-Hodgkin's lymphoma (NHL) primarily of B cell origin. It occurs in both immuno-competent and immune-compromised patients. High dose m ethotrexate (HD-MTX) based chemotherapy is the standard therapy. Chemotherapy with whole brain radiation therapy (WBRT) improves response rates and survival compared with WBRT alone. However, due to the increased risk for neurotoxicity with WBRT, recent studies have focused on using chemotherapy alone. Methotrexate based multi-agent chemotherapy without WBRT is associated with similar t reatment rates and survival compared with regimens that include WBRT although controlled trials have not been performed. Because of the low incidence of this disease, it is difficult to conduct randomized controlled trials. In this article we have discussed about the past, present and emerging treatment options in patients with PCNSL.

Prognosis after high-dose chemotherapy followed by autologous stem-cell transplantation as first-line treatment in primary CNS lymphoma--a long-term follow-up study

BACKGROUND

High-dose chemotherapy followed by autologous stem-cell transplantation (HCT-ASCT) is a promising approach in eligible patients with primary central nervous system lymphoma (PCNSL). We report long-term data of patients who were treated according to HCT-ASCT containing protocols.

PATIENTS AND METHODS

We analyzed survival and relapse rates in 43 (<67 years) immunocompetent patients with newly diagnosed PCNSL being treated according to two different high-dose methotrexate-based protocols followed by high-dose carmustine/thiotepa (BCNU/TT) plus ASCT (±whole brain irradiation). Analysis was conducted for all patients (intention-to-treat) and those patients who actually received HCT-ASCT (per-protocol).

RESULTS

Thirty-four patients achieved complete remission, of those 12 relapsed (35%), while 6 of them relapsed 5 years after diagnosis. After a median follow-up of 120 months, median overall survival (OS) was reached after 104 months. Two- and 5-year OS was 81% and 70% and 2- and 5-year event-free survival (EFS) was 81% and 67%, respectively. In per-protocol analysis (N = 34), 5-year OS and EFS was 82% and 79%, respectively. HCT-ASCT associated related mortality was not observed.

CONCLUSIONS

Sequential high-dose MTX containing chemotherapy followed by high-dose carmustine/thiotepa plus ASCT (±whole brain irradiation) is safe and leads to high survival rates in eligible patients with newly diagnosed PCNSL.

Primary central nervous system lymphoma: implication of high-dose chemotherapy followed by auto-SCT

Primary central nervous system lymphoma is a rare and distinct subtype of non-Hodgkin's lymphoma that is sensitive to radiation and chemotherapy. Decisions regarding the initial therapeutic approach are influenced by age and risk of therapy-related neurotoxicity. Despite several albeit small phase II studies, and the acknowledged need for larger prospective trials, there is supporting evidence to consider auto-SCT following induction chemotherapy in patients with good performance status. The international extranodal lymphoma study group is conducting a randomized phase II study comparing consolidative radiation therapy to high-dose therapy. Novel therapeutic options including early aggressive approach with upfront auto-SCT and strategies to prevent relapse following transplantation is an area of focus.

How I treat primary CNS lymphoma

Primary CNS lymphoma (PCNSL) is a rare malignancy with peculiar clinical and biologic features, aggressive course, and unsatisfactory outcome. It represents a challenge for multidisciplinary clinicians and scientists as therapeutic progress is inhibited by several issues. Molecular and biologic knowledge is incomplete, limiting the identification of new therapeutic targets, and the particular microenvironment of this malignancy, and sanctuary sites where tumor cells grow undisturbed, strongly affects treatment efficacy. Moreover, active treatments are known to be associated with disabling neurotoxicity, posing the dilemma of whether to intensify therapy to improve the cure rate or to de-escalate treatment to avoid sequels. The execution of prospective trials is also difficult because of the rarity of the tumor and the impaired general condition and poor performance status of patients. Thus, level of evidence is low, with consequent uncertainties in therapeutic decisions and lack of consensus on primary endpoints for future trials. Despite this unfavorable background, laboratory and clinical researchers are coordinating efforts to develop new ideas, resulting in the recent publication of studies on PCNSL's biology and molecular mechanisms and of the first international randomized trials. Herein, these important contributions are analyzed to provide recommendations for everyday practice and the rationale for future trials.

Chemotherapy in newly diagnosed primary central nervous system lymphoma

Primary central nervous system lymphoma (PCNSL) accounts for only 3% of brain tumors. It can involve the brain parenchyma, leptomeninges, eyes and the spinal cord. Unlike systemic lymphoma, durable remissions remain uncommon. Although phase III trials in this rare disease are difficult to perform, many phase II trials have attempted to define standards of care. Treatment modalities for patients with newly diagnosed PCNSL include radiation and/or chemotherapy. While the role of radiation therapy for initial management of PCNSL is controversial, clinical trials will attempt to improve the therapeutic index of this modality. Routes of chemotherapy administration include intravenous, intraocular, intraventricular or intra-arterial. Multiple trials have outlined different methotrexate-based chemotherapy regimens and have used local techniques to improve drug delivery. A major challenge in the management of patients with PCNSL remains the delivery of aggressive treatment with preservation of neurocognitive function. Because PCNSL is rare, it is important to perform multicenter clinical trials and to incorporate detailed measurements of long-term toxicities. In this review we focus on different chemotherapeutic approaches for immunocompetent patients with newly diagnosed PCNSL and discuss the role of local drug delivery in addition to systemic therapy. We also address the neurocognitive toxicity of treatment.

Therapeutic challenges in primary CNS lymphoma

Optimum treatment for patients with primary CNS lymphoma remains challenging because there have not been any large randomised clinical trials of this rare tumour. Drugs used in treating systemic non-Hodgkin lymphoma have mostly proven ineffective because of difficulties crossing the blood-brain barrier. The recognition of the efficacy of high-dose methotrexate was a substantial therapeutic breakthrough and further advances, such as the development of polychemotherapy regimens, have built on this. Whole-brain radiotherapy can consolidate response to chemotherapy, but the associated toxic effects of chemoradiation can be unacceptable. Other effective approaches include disruption of the blood-brain barrier and the use of high-dose chemotherapy. Recently, there have been attempts to optimise multi-drug chemotherapy regimens by focusing on improving survival and reducing toxic effects. A promising area of research is the incorporation of novel targeted drugs into standard treatment frameworks. In the future, greater cooperation between research groups should hopefully lead to further therapeutic advances.

Favorable outcome of primary CNS anaplastic large cell lymphoma in an immunocompetent patient

A 9-year-old immunocompetent male patient with primary central nervous system anaplastic large cell lymphoma was treated with 5 cycles of intensive chemotherapy including high-dose Ara-C, high-dose methotrexate, etoposide, and carmustine along with intraventricular chemotherapy followed by high-dose thiotepa and carboplatin with autologous peripheral blood hematopoietic stem cell transplantation. He received radiotherapy as the final therapy and has remained in remission for 26 months off therapy.

High-dose chemotherapy supported by autologous stem cell transplantation in patients with primary central nervous system lymphoma: facts and opinions

The standard approach to primary central nervous system lymphomas (PCNSL), that is high-dose methotrexate (HD-MTX)-based chemotherapy followed by whole-brain irradiation (WBRT), is associated with disappointing outcome. Moreover, this strategy is heavily conditioned by increased risk of disabling neurotoxicity, mostly among elderly patients. Several drugs and strategies have been investigated to improve results and neurotolerability. Among others, some investigators focused on the use of high-dose chemotherapy supported by autologous stem cells transplant (HDC/ASCT) as consolidation after primary chemotherapy. This approach has been used as salvage therapy in patients who experienced progressive disease or relapse after conventional chemo-radiotherapy or as consolidation after primary HD-MTX-based chemotherapy, replacing or preceding WBRT. Evidence supporting the role of HDC/ASCT is growing but several questions are still unanswered. The best conditioning regimen, the role of concomitant intrathecal chemotherapy, the neurotoxicity risk of further WBRT after transplant, the best time for response assessment and late effects both on neurological performance and extraneural organs remain to be characterised. This critical review is focused on the analysis of published experiences on HDC/ASCT in PCNSL in order to provide preliminary answers to the most pressing questions in this field.

Treatment of primary central nervous system lymphoma

Primary central nervous system lymphoma (PCNSL) is a rare form of extranodal non-Hodgkin's lymphoma that is typically confined to brain, eyes, and cerebrospinal fluid without evidence of systemic spread. The prognosis of patients with PCNSL has improved during the past decade with the introduction of high-dose methotrexate with or without whole brain radiotherapy. However, despite recent progress, results following treatment are durable in few patients, and therapy can be associated with late neurotoxicity. PCNSL is an uncommon tumor, and no phase III trial has been completed so far, leaving many questions about its optimum first-line and salvage treatments unanswered. This review summarizes the literature regarding the treatment of PCNSL in immunocompetent patients.

Primary CNS lymphoma

Primary CNS lymphoma, an uncommon form of extranodal non-Hodgkin's lymphoma, has increased in incidence and occurs in both immunocompromised and immunocompetent hosts. Primary CNS lymphoma in immunocompetent patients is associated with unique diagnostic, prognostic and therapeutic issues and the management of this malignancy is different from other forms of extranodal non-Hodgkin's lymphoma. Characteristic imaging features should lead to suspicion of the diagnosis, avoidance of corticosteroids (if possible) and early neurosurgical consultation for stereotactic biopsy. Since primary CNS lymphoma may involve the brain, cerebrospinal fluid and eyes, diagnostic evaluation should include assessment of all of these regions as well as screening for the possibility of occult systemic disease. Resection provides no therapeutic benefit and should be reserved for the rare patient with neurological deterioration due to brain herniation. Whole-brain radiation therapy alone is insufficient for durable tumor control and is associated with a high risk of neurotoxicity in patients over 60 years of age. Neurotoxicity is typically associated with significant cognitive, motor and autonomic dysfunction and has a negative impact on quality of life. Chemotherapy and whole-brain radiation therapy together improve tumor response rates and survival compared with whole-brain radiation therapy alone. Methotrexate-based multiagent chemotherapy without whole-brain radiation therapy is associated with similar tumor response rates and survival compared with regimens that include whole-brain radiation therapy, although controlled trials have not been performed. The risk of neurotoxicity is lower in patients treated with chemotherapy alone. The incidence of HIV-related primary CNS lymphoma has decreased in the era of highly active antiretroviral therapy. Patients with HIV-associated primary CNS lymphoma have a worse prognosis but may respond to highly active antiretroviral therapy, whole-brain radiation therapy or therapies directed against the Epstein-Barr virus.

Treatment of primary central nervous system lymphoma

Primary central nervous system lymphoma (PCNSL) is a rare form of extranodal non-Hodgkin's lymphoma that is typically confined to brain, eyes, and cerebrospinal fluid without evidence of systemic spread. The prognosis of patients with PCNSL has improved during the past decade with the introduction of high-dose methotrexate with or without whole brain radiotherapy. However, despite recent progress, results following treatment are durable in few patients, and therapy can be associated with late neurotoxicity. PCNSL is an uncommon tumor, and no phase III trial has been completed so far, leaving many questions about its optimum first-line and salvage treatments unanswered. This review summarizes the literature regarding the treatment of PCNSL in immunocompetent patients.

An Update on Primary Central Nervous System Lymphoma

The most important recent advance in treatment of primary central nervous system lymphoma has been the introduction of high-dose methotrexate-based chemotherapy. Convincing data demonstrate that the regimens of such chemotherapy improve survival compared with historical controls treated with radiotherapy alone. However, the optical treatment approach is still unclear and therapy can be associated with long-term neurotoxicity. Current research focuses on maximizing survival while minimizing neurologic sequelae.

Primary central nervous system lymphoma in children

Primary central nervous system lymphoma (PCNSL) is a very rare brain tumor in children, and the optimal management and prognosis of such patients have yet to be defined. In this study, the incidence rate, clinical features, diagnosis, and treatment of childhood PCNSL are reviewed. Except for human immunodeficiency virus-related PCNSL, the prognosis for patients with this tumor type is significantly better in children than in adults. In the absence of prospective studies, it is very difficult to determine the true incidence and the best therapeutic strategy for this rare entity. The majority of children with PCNSL, however, can achieve long-term remissions with intensive chemotherapy alone (an estimated 70% 5-year event-free survival rate), and cranial irradiation can be reserved for relapse of the disease. Further progress in the management of childhood PCNSL will require prospective multinational studies.

An Update on Therapy of Primary Central Nervous System Lymphoma

The most important advance in primary central nervous system (CNS) lymphoma treatment has been the convincing data that high-dose methotrexate-based chemotherapy regimens improve survival compared to historical controls treated with radiotherapy alone. However, the optimal treatment approach is still unclear and therapy can be associated with long-term neurotoxicity. Current research focuses on maximizing survival while minimizing neurologic sequelae.