Salvage therapy with bendamustine for methotrexate refractory recurrent primary CNS lymphoma: a retrospective case series

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.

Systemic Relapse in a Young Adult Patient with Primary CNS Diffuse Large B-Cell Lymphoma

Primary central nervous system diffuse large B-cell lymphoma (PCNS-DLBCL) is a rare form of non-Hodgkin's lymphoma, characterized by an aggressive disease course. While CNS relapse is common, systemic relapse is rare with no consensus on optimal treatment. This paper presents an unusual case of advanced PCNS-DLBCL with systemic relapse, including adrenal gland involvement. A review of the existing literature and a discussion on the management of systemic relapse in PCNS-DLBCL is also provided.

Cooccurrence of CD10-Positive and CD10-Negative Mantle Cell Lymphoma Complicated With Central Nervous System Involvement Solely by CD10-Positive Population

The neoplastic cells of mantle cell lymphoma (MCL) usually express CD5 and not CD10. However, cases of MCL with aberrant expression of CD10 have been seldom reported. A 71-year-old man presented multiple lymphadenopathies with a bulky tumor of the abdomen. He received the biopsies from the left cervical lymph node and the duodenum. The former specimen showed MCL with CD5-positive and CD10-negative, but the latter showed MCL with CD5-positive and CD10-positive. After receiving induction therapy, he developed convulsions, and lymphoma cells expressing CD5-positive and CD10-positive were detected in cerebrospinal fluid (CSF). CD10-positive MCL has some significant clinical characteristics. And it shows worse overall survival compared with CD10-negative MCL when it has aggressive features such as blastoid and pleomorphic morphology, high-Ki-67 index, and high mantle cell lymphoma international prognostic index (MIPI). Therefore, physicians and pathologists must carefully discriminate against cases having this aberrant expression.

Patients with marginal zone dural lymphoma successfully treated with rituximab and bendamustine: A report of two cases

Primary dural low-grade marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue (MALT) is a rare disease whose main treatment has been local surgery or radiotherapy. Until now, there have been no cases of dural MALT lymphoma treatment of a patient with several relapses or systemic disease. The present study included two patients with dural MALT lymphoma who had several relapses or systemic disease. Since local therapy was not enough to control the disease for these patients, they were treated with systemic chemotherapy. The patients were administered rituximab (375 mg/m²) and two days of bendamustine (90 mg/m²). Both patients recovered from their clinical symptoms immediately, and their tumors were reduced. During and after rituximab and bendamustine therapy, no central nervous system (CNS) metastasis or cerebrospinal fluid invasion of MALT were observed. The current approach using rituximab and bendamustine treatment was effective against dural MALT lymphoma and may prevent its invasion of the CNS.

Central Nervous System Lymphoma: Approach to Diagnosis and Treatment

Central nervous system lymphoma (CNSL) is a rare form of extranodal non-Hodgkin lymphoma. Central nervous system lymphoma can be primary (isolated to the central nervous space) or secondary in the setting of systemic disease. Treatment of CNSL has improved since the introduction of high-dose methotrexate and aggressive consolidation regimens. However, results after treatment are durable in only half of patients, and long-term survivors may experience late neurotoxicity, impacting quality of life. Given the rarity of this disease, few randomized prospective trials exist. This leaves many questions unanswered regarding optimal first-line and salvage treatments. Recent advances in the knowledge of pathophysiology of CNSL will hopefully help the development of future treatments. This review gives an overview of the epidemiology, pathophysiology, clinical presentation, diagnosis, and treatment of immunocompetent patients with CNSL.

Relapsed Primary Central Nervous System Lymphoma: Current Advances

Primary central nervous system lymphoma is an invasive malignant lymphoma confined to the central nervous system. Although patients undergoing first-line treatment can achieve complete response, most of them still relapse within two years. Relapsed lymphoma is derived from occult lymphoma cells, and B cell receptor pathway activation and immune escape are the key mechanisms for the pathogenesis of PCNSL. Most relapses are in the central nervous system, a small number of relapses are isolated systemic relapses, and clinical symptoms occur early and vary. Current treatments for relapse include high-dose methotrexate rechallenge and other regimens of chemotherapy, whole-brain radiation therapy, hematopoietic stem-cell transplantation, targeted therapy and immunotherapy, which have become promising treatments. The overall prognosis of relapsed PCNSL is very poor, although it is affected by many factors. This article summarizes the mechanisms, related factors, clinical features, follow-up, treatment and prognosis of relapsed primary central nervous system lymphoma.

Systemic Approach to Recurrent Primary CNS Lymphoma: Perspective on Current and Emerging Treatment Strategies

There is no uniform standard of care for the treatment of refractory or recurrent primary central nervous lymphoma (r/r PCNSL). Many different systemic treatment regimens have been studied, but available data are based on small prospective or retrospective reports. There have been no randomized controlled trials in r/r PCNSL to date. Here, we provide an overview of published systemic regimens for the treatment of r/r PCNSL, as well as therapies that are under investigation. In addition, based on available data, we propose strategies of how to approach choice of therapy for different groups of patients in this disease setting. Patients can be mainly divided into three groups: 1) patients suitable for a re-challenge with high-dose methotrexate (HD-MTX)-based regimens and that may or may not be candidates for consolidation with high-dose chemotherapy with autologous stem cell transplant, 2) patients refractory to HD-MTX or that had early relapse, but suitable for an aggressive treatment strategy with re-induction with non-MTX-based therapy, possibly followed by high-dose chemotherapy with autologous transplant, and 3) patients not suitable for re-treatment with HD-MTX and that are not candidates for aggressive therapy. As PCNSL is a rare disease and as there is urgent need for better outcomes in r/r PCNSL, clinical trial participation is encouraged, especially in elderly or frail patients who are not candidates for high-dose chemotherapy and transplant.

Advances and challenges in the treatment of primary central nervous system lymphoma

Primary central nervous system lymphoma (PCNSL), a rare variant of non-Hodgkin's lymphoma, is characterized by distinct biological characteristics and clinical behaviors, and patient prognosis is not satisfactory. The advent of high-dose (HD) methotrexate (HD-MTX) therapy has significantly improved PCNSL prognosis. Currently, HD-MTX-based chemotherapy regimens are recognized as first-line treatment. PCNSL is sensitive to radiotherapy, and whole-brain radiotherapy (WBRT) can consolidate response to chemotherapy; however, WBRT-associated delayed neurotoxicity leads to neurocognitive impairment, especially in elderly patients. Other effective approaches include rituximab, temozolomide, and autologous stem-cell transplantation (ASCT). In addition, new drugs against PCNSL such as those targeting the B-cell receptor signaling pathway, are undergoing clinical trials. However, optimal therapeutic approaches in PCNSL remain undefined. This review provides an overview of advances in surgical approaches, induction chemotherapy, radiotherapy, ASCT, salvage treatments, and novel therapeutic approaches in immunocompetent patients with PCNSL in the past 5 years. Additionally, therapeutic progress in elderly patients and in those with relapsed/refractory PCNSL is also summarized based on the outcomes of recent clinical studies.

Durable Response to Brentuximab Vedotin-Based Chemotherapy in Refractory Hodgkin Lymphoma with Central Nervous System (CNS) Involvement

BACKGROUND CNS involvement in Hodgkin lymphoma is rare. Despite various treatment options, median overall survival is only 13 months after diagnosis of CNS involvement in relapsed/refractory HL. CASE REPORT A 29-year-old woman with classical HL (mixed cellularity) in clinical stage IIB was treated with multilineage chemotherapy and radiotherapy without achieving a sustained complete remission. Systemic and CNS progression of HL occurred at the age of 32 years and the patient received 2 cycles of brentuximab vedotin with bendamustine alternating with 2 cycles of high-dose methotrexate-based treatment and achieved partial remission. She then underwent autologous stem cell transplantation followed by brentuximab vedotin consolidation. The disease progressed and the patient died 6 months after the last dose of brentuximab vedotin. CONCLUSIONS We demonstrated a durable response to brentuximab vedotin-based chemotherapy in a patient with refractory Hodgkin lymphoma with CNS involvement. Prognosis of these patients is poor and new treatment options are needed.

Introduction of novel agents in the treatment of primary CNS lymphoma

Novel insights into the pathophysiology of primary central nervous system lymphoma (PCNSL) have identified the B-cell receptor and Toll-like receptor pathway as well as immune evasion and suppressed tumor immune microenvironment as a key mechanism in the pathogenesis of PCNSL. Small molecules and novel agents targeting these aberrant pathways have been introduced into clinical trials targeting the recurrent or refractory PCNSL patient population. Agents like the Bruton tyrosine kinase (BTK) inhibitor ibrutinib or immunomodulatory drugs (IMiDs) like pomalidomide and lenalidomide have shown promising high response rates in the salvage setting. Here, we give an overview about the recent, exciting developments in PCNSL and summarize the results of clinical trials using novel agents in the recurrent and refractory salvage setting, which include immune checkpoint inhibitors, IMiDs, as well as BTK, phosphatidylinositol-3 kinase, and mammalian target of rapamycin inhibitors.

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.

Improving outcomes in primary CNS lymphoma

Primary central nervous system lymphoma (PCNSL) is an aggressive disease with previously poor prognosis. The advent of high-dose methotrexate-based induction regimens as well as use of consolidation therapy has greatly improved this prognosis in recent decades, but durable remission still eludes half of patients. In this review, we summarize the progress made in the treatment of PCNSL as well as the challenges that remain, with a focus on defining optimal induction and consolidation regimens, including the promise of developing biotherapies. Future studies will help delineate the best combination of existing and novel treatment strategies, with the goal of expanding the cohort of patients achieving a cure.

Clinical response and pharmacokinetics of bendamustine as a component of salvage R-B(O)AD therapy for the treatment of primary central nervous system lymphoma (PCNSL)

Background

A relatively high proportion of patients diagnosed with primary CNS lymphoma will experience recurrent disease, yet therapy options are limited in salvage therapy. This is the first study to evaluate a bendamustine-based combination regimen for the treatment of relapsed/refractory PCNSL and to characterize bendamustine pharmacokinetics in the human CSF.

Methods

Patients received bendamustine 75 mg/m² for two days as part of R-B(O)AD administered intravenously every 4 weeks for up to 4 cycles. Response and adverse events of the regimen were assessed. A sparse sampling strategy and population based modeling approach was utilized for evaluation of plasma and CSF levels of bendamustine.

Results

Ten patients were enrolled into study of whom 70% were of refractory disease and with high IELSG prognostic risk scores. The ORR of R-BOAD was 50% (95% CI, 0.24 to 0.76) with one patient achieving CR and four PR. Primary toxicity of the regimen was reversible myelosuppression, mostly grade 3 or 4 neutropenia. The C_max mean for plasma and CSF were 2669 ng/mL and 0.397 ng/mL, respectively, and patients with response at deep tumor sites displayed higher trends in peak exposure. Pharmacokinetic data was best described by a four-compartment model with first-order elimination of drug from central plasma and CSF compartments.

Conclusions

R-BOAD is an effective salvage option for PCNSL, but with significant hematologic toxicity. Bendamustine CSF levels are minimal; however correspond to plasma exposure and response.

Trial registration

ClinicalTrials.gov NCT03392714; retrospectively registered January 8, 2018.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-4632-y) contains supplementary material, which is available to authorized users.

Combined alkylation and histone deacetylase inhibition with EDO-S101 has significant therapeutic activity against brain tumors in preclinical models

There is a clear unmet need for novel therapeutic agents for management of primary and secondary brain tumors. Novel therapeutic agents with excellent central nervous system (CNS) penetration and therapeutic activity are urgently needed. EDO-S101 is a novel alkylating and histone deacetylase inhibiting agent created by covalent fusion of bendamustine and vorinostat. We used murine models to perform CNS pharmacokinetic analysis and preclinical therapeutic evaluation of EDO-S101 for CNS lymphoma, metastatic triple-negative breast cancer of the brain, and glioblastoma multiforme. EDO-S101 has excellent CNS penetration of 13.8% and 16.5% by intravenous infusion and bolus administration respectively. It shows promising therapeutic activity against CNS lymphoma, metastatic triple-negative breast cancer of the brain, and glioblastoma multiforme with significant prolongation of survival compared to no-treatment controls. Therapeutic activity was higher with IV infusion compared to IV bolus. It should be evaluated further for therapeutic use in brain tumors.

Treatment of Primary Central Nervous System Lymphoma: From Chemotherapy to Small Molecules

Primary central nervous system lymphoma (PCNSL) is a rare form of extranodal non-Hodgkin lymphoma that is typically confined to the brain, eyes, and cerebrospinal fluid (CSF) without evidence of systemic spread. PCNSL is an uncommon tumor, and only four randomized trials and one phase III trial have been completed so far, all in the first-line setting. The prognosis of patients with PCNSL has improved during the past few decades with the introduction of high-dose methotrexate (HD-MTX), which now serves as the backbone of all first-line treatment regimens. Despite recent progress, results after treatment are durable in half of patients, and therapy can be associated with late neurotoxicity. Novel insights into the pathophysiology of PCNSL have identified the B-cell receptor (BCR) pathway as a key mechanism in the pathogenesis of PCNSL. The use of novel agents targeting components of the BCR pathway, namely the Bruton tyrosine kinase (BTK) inhibitor ibrutinib, and immunomodulatory drugs (IMIDs) like lenalidomide and pomalidomide, has so far been limited to patients who have recurrent/refractory PCNSL with promising high response rates. Within the past 5 years, there has been a peak in clinical trials investigating small molecules and novel reagents in the recurrent/refractory setting, including immune checkpoint inhibitors, IMIDs, and BTK and PI3K/AKT/mTOR inhibitors.

Challenges and prospects in the diagnosis and treatment of primary central nervous system lymphoma

Introduction: Primary central nervous system lymphoma (PCNSL) retains peculiar biological and clinical characteristics and a worse prognosis with respect to other comparable lymphomas. The need for high doses of chemotherapy to achieve valid drug concentrations in cerebral tissues and/or radiotherapy results in severe treatment-related toxicities, mainly neurologic, which are frequently as disabling as the disease itself.Areas covered: Several emerging combined therapies are addressed that focus on treating PCNSL. The prognosis has improved in the last years but several questions remain unanswered and the research of more effective therapies goes on. Information and data were obtained from direct authors' experience and a PubMed search of recent peer-reviewed original articles, review articles, and clinical guidelines.Expert commentary: The substantial progress observed in PCNSL has to be ascribed to a carefully combination of standard chemotherapeutic drugs. High-dose methotrexate-based polychemotherapy followed by mainteinance therapy offers one of the best chances to control the disease. Major issues that deserve many efforts by researchers are the definition of optimal consolidation treatment and a shared management of specific conditions such as elderly population and intra-ocular localization.

Immunochemotherapy using rituximab (RTX) and high-dose methotrexate (HD-MTX): an evaluation of the addition of RTX to HD-MTX in recurrent primary central nervous system lymphoma (PCNSL)

Background

There is increasing evidence that MTX-based chemotherapy is superior to HD-MTX alone. Rituximab (RTX) is effective in a variety of B-cell lymphomas and may enter the brain. The purpose of this study is to evaluate the addition of RTX to HD-MTX in recurrent primary central nervous system lymphoma (PCNSL).

Methods

Patients diagnosed with recurrent PCNSL at our institution between 2004 and 2009 were treated with HD-MTX (3.5-5.5 g/m2) every 2 weeks. From 2010, RTX (375 mg/m2) was administered every 2 weeks along with HD-MTX.

Results

Fifteen recurrences in 10 patients were treated with HD-MTX alone (MTX group). Another 15 recurrences in 10 patients were treated with RTX and HD-MTX (RTX group). In 13 (86.6%) of the 15 recurrences in both groups the pre-planned chemotherapy cycles were completed. In the MTX group, 10/15 (66.6%) recurrences achieved a complete response (CR/CRu), 2/15 (13.3%) recurrences achieved a partial response (PR) and 3/15 (20%) recurrences had progressive disease (PD). In the RTX group, the CR/CRu, PR and PD rates were the same as that in the MTX group. The median time to tumor progression (mTTP) was 9.1 months (range, 1.4-120.9 months) in the MTX group and 7.8 months (range, 0.9-52.3 months) in the RTX group. We found no significant difference in mTTP (9.1 vs. 7.8 months, HR 1.02, 95% CI 0.48-2.18, P = 0.94) between the two groups. All treatment-related toxicities were manageable without any severe events.

Conclusions

The addition of RTX to HD-MTX may not be a promising strategy for recurrent PCNSL. A future study with a larger sample size, longer follow-up, or different RTX dosing/schedule is warranted.

Primary CNS Lymphoma

Primary CNS lymphoma (PCNSL) is a rare form of extranodal non-Hodgkin lymphoma that is typically confined to the brain, eyes, and cerebrospinal fluid without evidence of systemic spread. The prognosis of patients with PCNSL has improved during the last decades with the introduction of high-dose methotrexate. However, despite recent progress, results after treatment are durable in half of patients, and therapy can be associated with late neurotoxicity. PCNSL is an uncommon tumor, and only four randomized trials and one phase III trial have been completed so far, all in the first-line setting. To our knowledge, no randomized trial has been conducted for recurrent/refractory disease, leaving many questions unanswered about optimal first-line and salvage treatments. This review will give an overview of the presentation, evaluation, and treatment of immunocompetent patients with PCNSL.

Case-based review: primary central nervous system lymphoma

Primary CNS lymphoma (PCNSL) is a rare diffuse large B-cell lymphoma originating within the central nervous system. The overall incidence of PCNSL is rising, particularly in the elderly population. Immunosuppression is a strong risk factor, but most patients with this tumor are apparently immunocompetent. Diagnosis of PCNSL can be challenging. Non-invasive or minimally invasive tests such as ophthalmological evaluation and spinal fluid analysis may be useful, but the majority of patients require tumor biopsy for definitive diagnosis. Our knowledge concerning optimum treatment of PCNSL is fragmentary due to paucity of adequately sized trials. Most patients are now initially treated with high-dose-methotrexate-based chemotherapy alone, as the addition of whole-brain radiotherapy at standard doses has not been shown to increase survival and does increase the risk of neurological toxicity. Ongoing trials are addressing issues such as the roles of reduced-dose radiotherapy, the addition of the CD20 antibody rituximab to chemotherapy, high-dose chemotherapy followed by autologous stem cell transplantation, and maintenance therapy in the primary management of PCNSL.

Central nervous system involvement by Waldenström macroglobulinaemia (Bing-Neel syndrome): a multi-institutional retrospective study

Bing-Neel syndrome (BNS) is a rare complication seen in patients with Waldenström macroglobulinaemia (WM), in which lymphoplasmacytic lymphoma cells colonize the central nervous system. In this retrospective multi-centre study, we present the clinicopathological features, imaging findings, therapy, response and outcomes of 34 patients with BNS. The median time from WM diagnosis to BNS diagnosis was 3 years, 15% of patients were diagnosed with BNS at the time of WM diagnosis, and 22% of patients developed BNS when responding to active treatment for WM. Patients with BNS presented with variable clinical features including limb motor deficits, change in mental status and cranial nerve palsies. The diagnosis was made using a combination of cerebrospinal fluid cytology, flow cytometry and detection of the MYD88 L265 mutation, and magnetic resonance imaging. The estimated 3-year overall survival rate was 59%. Of the survivors, 40% have evidence of pathological and/or radiological persistence of disease. Age older than 65 years, platelet count lower than 100 × 10(9) /l, and treatment for WM prior to BNS diagnosis were associated with worse outcome. Exposure to rituximab for treatment of BNS was associated with a better outcome. Multi-institutional collaboration is warranted to improve treatment and outcomes in patients with BNS.

Thiotepa-based high-dose therapy for autologous stem cell transplantation in lymphoma: a retrospective study from the EBMT

Clinical information about thiotepa-based autologous stem cell transplantation (auto-SCT) outside the primary central nervous system lymphoma (PCNSL) field is sparse. In this registry-based retrospective study, we evaluated potential risks and benefits of thiotepa-based preparative regimens compared with BEAM (carmustine, etoposide, cytarabine, melphalan) in auto-SCT for diffuse large B-cell lymphoma (DLBCL, excluding PCNSL), follicular lymphoma (FL) or Hodgkin lymphoma (HL). A total of 14 544 patients (589 thiotepa and 13 955 BEAM) met the eligibility criteria, and 535 thiotepa- and 1031 BEAM-treated patients were matched in a 1:2 ratio for final comparison. No significant differences between thiotepa and BEAM groups for any survival end point were identified in the whole sample or disease entity subsets. For a more detailed analysis, 47 TEAM (thiotepa, etoposide, cytarabine, melphalan)-treated patients were compared with 75 matched BEAM patients with additional collection of toxicity data. Again, there were no significant differences between the two groups for any survival end point. In addition, the frequency of common infectious and non-infectious complications including secondary malignancies was comparable between TEAM and BEAM. These results indicate that thiotepa-based high-dose therapy might be a valuable alternative to BEAM in DLBCL, HL and FL. Further evaluation by prospective clinical trials is warranted.

High-dose cytarabine salvage therapy for recurrent primary CNS lymphoma

Treatment of recurrent primary CNS lymphoma (PCNSL) though not standardized most often utilizes whole brain radiotherapy, re-challenge with high-dose methotrexate, or administration of an alkylating chemotherapy. High-dose cytarabine (HD-araC) has been advocated as an active agent in PCNSL but limited information exists regarding single agent activity in the recurrent setting. A retrospective review of 14 patients (10 males, 4 females: median age 60 years) with recurrent PCNSL treated at second recurrence with single agent HD-araC. HD-araC was administered at 3gm/m(2) over a 3-h infusion every 12 h for a total of 4 doses (defined as a cycle of therapy). GM-CSF was administered at conclusion of HD-araC. Patients were clinically and radiographically evaluated every 4-weeks. Common toxicity criteria Grade 3 or 4 toxicity included thrombocytopenia (11 patients; 79%), anemia (10; 71%), fatigue (8; 57%), mucositis (8; 57%), neutropenia (8; 57%) and neutropenic fever (5; 36%). No patient discontinued therapy due to toxicity nor were there any treatment-related deaths. Best response to HD-araC was stable disease in 6 patients (43%), partial response in 5 (36%) and progressive disease in 3 (21%). Median progression free survival 3 months (range 2-5 months; 95% CI 2-4 months) and progression free survival was 0% at 6-months. Median survival after onset of HD-araC was 12 months (range 3-18+ months; 95% CI 3-15 months). Single agent HD-araC has limited activity in recurrent PCNSL and is associated with significant toxicity in this small retrospective study.

A case of neurolymphomatosis caused by follicular lymphoma successfully treated with bendamustine

Currently, there is no standard treatment for neurolymphomatosis because of the scarcity of clinical studies. Here, we report the successful treatment of neurolymphomatosis caused by follicular lymphoma with bendamustine, which could be an effective treatment option for this condition.

Efficacy of Procarbazine, Lomustine, and Vincristine Chemotherapy for Recurrent Primary Central Nervous System Lymphomas

Background

Optimal treatment for recurrent primary central nervous system lymphomas (PCNSLs) has not been defined yet and there is no general consensus about the salvage chemotherapy after high-dose methotrexate (HD-MTX)-based chemotherapy. The purpose of the present study was to evaluate the efficacy and safety of procarbazine, lomustine, and vincristine (PCV) chemotherapy for recurrent PCNSLs.

Methods

We reviewed eight immunocompetent patients (five males/three females, mean age: 56 years) who received salvage PCV chemotherapy (procarbazine 60 mg/m², days 8 through 21: CCNU 110 mg/m², day 1: vincristine 2 mg, days 8 and 28) for recurrent PCNSL and two patients switched to PCV chemotherapy due to severe adverse effects of HD-MTX chemotherapy. Radiologic responses, survival, and adverse effects were analyzed.

Results

Of the eight recurrent PCNSLs, three patients (37.5%) showed radiologic complete response, one patient (12.5%) showed partial response, and four patients (50%) showed progressive disease after PCV chemotherapy. Median progression free survival (PFS) from the first administration of PCV to relapse or last follow-up was 7 months (range 5-32 months) and median overall survival was 8 months (range 2-41 months). The two patients who switched to PCV chemotherapy showed PFS of 9 and 5 months from the beginning of PCV to relapse. The common side effects were thrombocytopenia, neutropenia, and peripheral neuropathy. There were 4 grade III or IV myelo-suppression, but no fatal complications, including severe hemorrhage or infection, were observed.

Conclusion

Salvage PCV chemotherapy has a moderate anti-lymphoma activity for recurrent PCNSLs after the HD-MTX-based chemotherapy with tolerable toxicity.

Primary CNS lymphoma

Primary diffuse large B-cell lymphoma (DLBCL) of the central nervous system is an aggressive malignancy that exhibits unique biological features and characteristic clinical behaviour, with overall long-term survival rates of around 20–40 %. Clinical outcome has improved following the advent of chemoradiation protocols incorporating high-dose methotrexate in the mid-1980s, but disease relapse and adverse neurocognitive sequelae remain major clinical challenges. To address this, investigators have focused on improving drug therapy with novel cytotoxic combinations, monoclonal antibody therapy, and intensive chemotherapy consolidation approaches, in an attempt to improve disease control whilst reducing the requirement for whole-brain radiotherapy. Outcomes for patients that are older, immunocompromised, or have relapsed/refractory disease remain unsatisfactory and there is a paucity of clinical trial data to guide treatment of these groups. This review highlights recent advances in pathobiology, imaging, and clinical management of PCNSL and looks ahead to research priorities for this rare and challenging lymphoid malignancy.