NOA-03 trial of high-dose methotrexate in primary central nervous system lymphoma: final report

Residual diffusion-weighted imaging hyperintense signal in primary central nervous system lymphoma can predict early recurrence

BACKGROUND

The treatment response of primary central nervous system lymphomas (PCNSLs) is mainly evaluated using postcontrast T1-weighted imaging (T1WI). Because poorly enhanced lesions may contain residual tumors, the combination of evaluation methods will potentially improve the accuracy of determining treatment effectiveness. In this study, we evaluated the usefulness of diffusion-weighted imaging (DWI) in predicting recurrence among patients with PCNSL who achieved complete response (CR)/unconfirmed CR (CRu).

METHODS

Fifty-four patients newly diagnosed with PCNSL who were treated at our institution and achieved CR/CRu at the end of treatment were included in this study. The patients were divided into two groups according to the presence or absence of residual DWI hyperintense signal at the tumor site at the end of treatment. Kaplan-Meier analysis was performed to analyze the median overall survival (OS) and progression-free survival (PFS).

RESULTS

The mean age of the 54 patients was 66.4 ± 13.3 years. The induction therapies were HD-MTX in 20 patients, R-MPV in 29 patients, and other chemotherapies in five patients. Radiotherapy was performed in 35 patients, high-dose cytarabine therapy in 14 patients, and autologous hematopoietic stem cell transplantation in one patient, and of the 54 patients, 10 had no consolidation therapy. The residual DWI hyperintense signal sign was observed in 18 patients. The R-MPV regimen was statistically associated with a lower rate of residual DWI hyperintense signal (p = 0.0453). The median PFS was statistically shorter in the residual DWI hyperintense signal group than in the non-residual DWI hyperintense signal group (14.0 months vs. 85.1 months) (p < 0.0001, log-rank test).

CONCLUSION

A residual DWI hyperintense signal at the end of treatment was statistically associated with shorter PFS. Among patients who achieved CR/CRu evaluated based on postcontrast T1WI, DWI could be a valuable additional sequence to predict the early recurrence of PCNSL.

Advances in therapeutic strategies for primary CNS B-cell lymphomas

INTRODUCTION

Primary CNS lymphoma (PCNSL) has traditionally been treated with induction HD-MTX-based chemotherapy, followed by consolidation whole-brain radiotherapy. However, this approach is associated with significant neurocognitive complications, especially in older patients. Therefore, different consolidation protocols have been evaluated. High-dose chemotherapy followed by autologous stem cell transplantation (HD-ASCT) has the best long-term survival outcomes in younger patients.

AREAS COVERED

In this review of the literature, we focus on the overall therapeutic strategy and advances in the management of the aggressive primary CNS B-cell lymphomas.

EXPERT OPINION

In young and fit PCNSL patients, HD-ASCT is the preferred consolidation strategy to achieve long-term survivals. Older patients with good performance status should also be evaluated for MTX-based induction polychemotherapy followed by ASCT. However, management of PCNSL patients remains challenging, and new avenues with targeted therapies are under investigation. To date, ibrutinib, lenalidomide, and immune checkpoint inhibitors appearto be promising in PCNSL. However, as monotherapy, durable responses are less likely to be achieved. Unfortunately, when combined with chemoimmunotherapy, considerable toxicity and mortality have been reported. Clinical trials on these molecules are aiming to reduce toxicity and maintain responses. CAR-T-cell therapy has recently emerged as a further option. It has shown efficacy in patients with secondary CNS lymphoma, with few but encouraging results in primary CNSL.

Improvement of outcomes of an escalated high-dose methotrexate-based regimen for patients with newly diagnosed primary central nervous system lymphoma: a real-world cohort study

Purpose

High‐dose methotrexate (HD‐MTX)-based chemotherapy regimen is the first-line treatment of primary central nervous system lymphoma (PCNSL). At present, doses of MTX in the range of 3.5–8 g/m² are frequently used. However, the optimal dose of methotrexate for PCNSL remains controversial. The purpose of this real-world study was to compare the efficacy and toxicity of HD-MTX in patients with untreated PCNSL.

Methods

Immunocompetent adults with newly diagnosed PCNSL between January 2015 and December 2018 were investigated and followed up to June 2019. All patients’ initial treatments were based on HD‐MTX chemotherapy regimens.

Results

A total of 73 patients were reviewed. For patients who received HD-MTX at 8 g/m² vs.3.5 g/m², the complete response (CR) rates were 68.29% vs 43.75% (p = 0.03), and the median PFS times were 17.7 months vs 9.05 months (HR=0.455, 95% CI 0.239–0.865, p=0.016). There was no significant difference in OS between the two groups. Serious adverse effects were uncommon and clinically manageable.

Conclusion

There is a correlation of treatment response and clinical outcomes between the dosage of MTX in initial induction therapy in newly diagnosed PCNSL. MTX dose of 8 g/m² provided a higher CR rate and PFS benefits with acceptable adverse effects.

Primary central nervous system lymphoma: a narrative review of ongoing clinical trials and goals for future studies

Primary central nervous system lymphoma (PCNSL) is a rare disease of the brain, spine, cerebrospinal fluid (CSF) and/or vitreoretinal space. PCNSL is chemo and radiosensitive but relapse is common even years after initial treatment. Outside of consensus regarding the use of high-dose methotrexate (HD-MTX) for first line treatment, there is little uniformity in the management of newly diagnosed or relapsed PCNSL. The lack of consensus is driven by a paucity of randomized trials in this disease. Prospective studies are troubled by low enrollment, the lack of a standard induction regimen, and a varied approach to consolidation strategies. Moreover, the PCNSL patient population is heterogeneous and includes a high proportion of elderly or frail patients and consists of patients manifesting disease in varied compartments of the central nervous system (CNS). As a result, current treatment strategies vary widely and are often dictated by physician and institutional preference or regional practice. This review provides an overview of recently completed and ongoing therapeutic studies for patients with newly diagnosed and recurrent or refractory PCNSL. It discusses the existing evidence behind common approaches to induction and consolidation or maintenance regimens as well as the recent data regarding management of recurrent disease. Finally, it highlights the complexity of trial design in this disease and provides a framework for the design of future studies, which are needed to identify patient populations likely to benefit from specific induction, consolidation, or maintenance therapies.

Foundations of Neuro-Oncology: A Multidisciplinary Approach

Neuro-oncology is a branch of medicine focused on the diagnosis and treatment of primary and secondary tumors of the nervous system as well as the neurologic complications of cancer and cancer treatments. In practice, neuro-oncologists require an intimate knowledge of the neurologic presentation and management of central nervous system tumors, including gliomas, meningiomas, primary central nervous system lymphoma, metastases to the nervous system, and others. The mainstays of treatment for most nervous system tumors include surgical intervention, radiation therapy, and medical treatment with chemotherapy, immunotherapy, and/or targeted therapy. Interdisciplinary collaboration is thus critical to neuro-oncology. The prognosis for many central nervous system tumors, including gliomas and brain metastases, is often poor despite the advent of novel medical therapies. Efforts to develop more effective therapies are ongoing, and patient enrollment in clinical trials assessing the efficacy of new treatments is crucial to improve outcomes.

High-dose methotrexate-based regimens and post-remission consolidation for treatment of newly diagnosed primary CNS lymphoma: meta-analysis of clinical trials

With the exception of high-dose methotrexate (HD-MTX), there is currently no defined standard treatment for newly diagnosed primary central nervous system lymphoma (PCNSL). This review focused on first-line induction and consolidation treatment of PCNSL and aimed to determine the optimal combination of HD-MTX and the long-term beneficial consolidation methods. A comprehensive literature search of MEDLINE identified 1407 studies, among which 31 studies met the inclusion criteria. The meta-analysis was performed by using Stata SE version 15. Forest plots were generated to report combined outcomes like the complete response rate (CRR), overall survival, and progression-free survival. We also conducted univariate regression analyses of the baseline characteristics to identify the source of heterogeneity. Pooled analysis showed a CRR of 41% across all HD-MTX-based regimens, and three- and four-drug regimens had better CRRs than HD-MTX monotherapy. In all combinations based on HD-MTX, the HD-MTX + procarbazine + vincristine (MPV) regimen showed pooled CRRs of 63% and 58% with and without rituximab, respectively, followed by the rituximab + HD-MTX + temozolomide regimen, which showed a pooled CRR of 60%. Pooled PFS and OS showed that post-remission consolidation with autologous stem cell transplantation (ASCT) was associated with the best survival outcome, with a pooled 2-year OS of 80%, a 2-year PFS of 74%, a 5-year OS of 77%, and a 5-year PFS of 63%. Next, whole-brain radiation therapy (WBRT) + chemotherapy showed a pooled 2-year OS of 72%, 2-year PFS of 56%, 5-year OS of 55%, and 5-year PFS of 41%, with no detectable CR heterogeneity throughout the entire treatment process. In HD-MTX-based therapy of newly diagnosed PCNSL, MPV with or without rituximab can be chosen as the inductive regimen, and the rituximab + HD-MTX + temozolomide regimen is also a practical choice. Based on our study, high-dose chemotherapy supported by ASCT is an efficacious approach for consolidation. Consolidation with WBRT + chemotherapy can be another feasible approach.

Outcomes of Autologous Stem Cell Transplant Consolidation in Primary Central Nervous System Lymphoma: A Mayo Clinic Experience

A paucity of randomized phase III clinical trials in primary central nervous system lymphoma (PCNSL) has resulted in no uniform consensus on the optimal strategy for consolidation and conditioning regimens for autologous stem cell transplant (ASCT). The past 2 decades have witnessed a preference for thiotepa (TT)-based conditioning regimens due to superior central nervous system penetration. We retrospectively evaluated outcomes of patients with PCNSL who underwent ASCT at Mayo Clinic, Rochester over the past 2 decades, and the impact of TT-based conditioning regimens. Fifty-six patients underwent transplant for PCNSL, with 25 and 31 patients receiving BEAM (non-thiotepa) and carmustine (BCNU)/TT-based conditioning, respectively. All patients received high-dose methotrexate-based induction therapy. While the BCNU/TT group had higher risk disease features such as high International Extranodal Lymphoma Study Group prognostic score, elevated cerebrospinal fluid protein, and older patient population, there was no significant difference at 2 years post-transplant in progression-free survival (BEAM 68.0% [46.1% to 82.5%] versus BCNU/TT, 65.5% [45.2% to 79.8%], P = .99) or overall survival (OS) (84.0% [62.8% to 93.7%] in the BEAM group versus 81.6% [61.3% to 91.9%] in the BCNU/TT group, P = .95). Disease response status before transplant significantly affected the outcomes as those in complete remission had an OS at 2 years post-transplant of 94.7% (68.1% to 99.2%) in the BEAM group and 90.5% (67.0% to 97.5%) in the BCNU/TT group compared with those in partial response, 57.1% (17.2% to 83.7%) in BCNU/TT group and 50.0% (11.1% to 80.4%) in the BEAM group, respectively (P < .0001). Our retrospective cohort adds to the currently available literature and identifies the disease status before transplant as a significant factor affecting survival.

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.

Comprehensive approach to diagnosis and treatment of newly diagnosed primary CNS lymphoma

Primary central nervous system lymphoma (PCNSL) is a rare form of non-Hodgkin lymphoma that affects the brain parenchyma, spinal cord, eyes, and cerebrospinal fluid without evidence of systemic, non-CNS involvement. PCNSL is uncommon and only a few randomized trials have been completed in the first-line setting. Over the past decades, the prognosis of PCNSL has improved, mainly due to the introduction and widespread use of high-dose methotrexate, which is now the backbone of all first-line treatment polychemotherapy regimens. Despite this progress, durable remission is recorded in only 50% of patients, and therapy can be associated with significant late neurotoxicity. Here, we overview the epidemiology, clinical presentation, staging evaluation, prognosis, and current up-to-date treatment of immunocompetent PCNSL patients.

Clinical Characteristics, Surgical Outcomes, and Prognostic Factors of Intracranial Primary Central Nervous System Lymphoma

BACKGROUND

Intracranial primary central nervous system lymphoma (PCNSL) is a rare aggressive malignant tumor with poor prognosis. The effect of surgical resection on intracranial PCNSL is still controversial. This study investigates the efficacy and safety of surgical resection, as well as to analyze the clinical characteristics and prognostic factors of intracranial PCNSL.

METHODS

The clinical materials of 89 consecutive patients with intracranial PCNSL were analyzed retrospectively. Outcome in survival was assessed by progression-free survival (PFS) and overall survival (OS). Univariate and multivariate analyses were performed for various potential prognostic factors to identify independent prognostic factors of intracranial PCNSL.

RESULTS

Among the 89 patients, gross total resection (GTR) was achieved in 57 patients (64.0%), subtotal resection (STR) in 14 patients (15.8%), and biopsy in 18 patients (20.2%).The PFS and OS at 2 years were estimated at 32.3% and 74.1%, respectively. The median PFS was 20 months (95% confidence interval, 16-23) and the median OS was 32 months (95% confidence interval, 25-38). Patients with surgical resection (GTR and STR) had better PFS than those with biopsy, and the difference of PFS was statistically significant (P = 0.007). However, the difference of OS was not statistically significant (P = 0.062). Multivariate analysis showed that invasion of deep structure was the only independent risk factor for intracranial PCNSL. Eleven patients (12.4%) had surgical complications, mainly including limb weakness and visual field defect.

CONCLUSIONS

For intracranial PCNSL, surgical excision can improve PFS but not OS. Invasion of deep structure was the only independent risk factor for intracranial PCNSL.

Continuous intrathecal injection therapy of methotrexate is a therapeutic option in primary CNS lymphoma

Primary central nervous system lymphoma (PCNSL) is a rare subtype of non-Hodgkin's lymphoma, and its prognosis is still very poor despite the conventional therapy of high-dose methotrexate (HD-MTX) followed by whole-brain radiation therapy (WBRT). The purpose of the present study was to evaluate the survival benefit of continuous intrathecal injection therapy of methotrexate (CIT-MTX) combined with the conventional therapy. A total of 26 PCNSL patients treated with CIT-MTX were analyzed. Ten mg of methotrexate were continuously injected into the lateral ventricle via a subcutaneous port over 5 days biweekly for 5 cycles. CIT-MTX was performed with WBRT in addition to HD-MTX in 15 cases, and 11 cases with high risk for HD-MTX were treated with CIT-MTX and WBRT. The response rate of all patients was 92.3%, and median progression-free survival and median overall survival (mOS) were 59.4 months and 93.8 months, respectively. Median OS of patients treated with CIT-MTX in addition to HD-MTX and WBRT was longer than the previously reported mOS with HD-MTX and WBRT (95 vs 33 months). In cases that could not tolerate HD-MTX, mOS of patients treated with CIT-MTX and WBRT was longer than the previously reported mOS with WBRT alone (36.7 vs 18 months). There was no difference in OS between patients with cerebrospinal fluid dissemination and patients without (p = 0.83). Better prognosis in patients treated with CIT-MTX may be derived from stable concentration of methotrexate in the cerebrospinal fluid. CIT-MTX was an effective additional therapeutic option for PCNSL.

Is whole-brain radiotherapy still a standard treatment for primary central nervous system lymphomas?

PURPOSE OF REVIEW

In primary central nervous system lymphomas (PCNSL), optimal therapy remains to be established, and the role of whole-brain radiotherapy (WBRT) is a matter of debate. With radiation alone, transient responses and clinical improvement are frequent, but long-term disease control is exceptional. WBRT has been considered possible consolidation therapy after high-dose methotrexate (HDMTX)-based initial chemotherapy. This strategy has been questioned due to a high risk of delayed neurotoxicity after combined treatment. This review analyses the current role of WBRT in PCNSL.

RECENT FINDINGS

Neither in retrospective analyses nor in randomized trials, an overall survival benefit with WBRT in addition to HDMTX-based initial chemotherapy could be found. On the other hand, a recent randomized trial did not show superiority of consolidation with high-dose chemotherapy followed by autologous stem-cell transplantation to consolidation WBRT after initial HDMTX-based polychemotherapy. This finding, however, is probably due to an intense initial therapy and to a small number of patients having reached consolidation and randomization to WBRT vs. high-dose chemotherapy followed by autologous stem-cell transplantation.

SUMMARY

The current role of WBRT in PCNSL is confined to patients who cannot tolerate chemotherapy or have failed it. WBRT should not routinely be used for consolidation of HDMTX-based chemotherapy due to lack of evidence of efficacy as additional treatment and due to a high risk of neurotoxicity.

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.

Central Nervous System Prophylaxis Strategies in Diffuse Large B Cell Lymphoma

OPINION STATEMENT

Central nervous system (CNS) relapse is an undesirable event in the course of patients with diffuse large B cell lymphoma (DLBCL) with a median survival of approximately 6 months following CNS relapse. CNS prophylaxis for the prevention of CNS recurrence, in addition to the standard R-CHOP chemotherapy, is thus preferable. For an overall relapse risk of 2-5%, administration of CNS-directed therapies for all patients with DLBCL is unnecessary and prophylaxis should be targeted for the high-risk patients. CNS-International Prognostic Index (CNS-IPI) score has enabled risk stratification with risk ranging < 1% (low-risk group) compared to > 10% (high-risk group). The latter could be considered for CNS prophylaxis. CNS-IPI, however, is not perfect and may not capture patients with high-risk extra-nodal sites such as testicular DLBCL. Cell-of-origin and MYC/BCL2 expression can further build on CNS-IPI to narrow higher risk patients. CNS prophylaxis strategies are controversial. Common strategies include intrathecal (IT) chemotherapy and systemic CNS penetrants such as methotrexate. IT chemotherapy does not adequately penetrate the brain parenchyma and hence it is insufficient in preventing parenchymal CNS recurrences. Most experts promote systemic methotrexate for high-risk groups, which penetrates both the leptomeningeal and parenchymal CNS compartments. Even though systemic CNS prophylaxis is widely promoted over IT alone, its efficacy is unclear. Ongoing efforts in search for appropriate CNS prophylaxis strategies are warranted. My personal practice is to administer systemic high-dose methotrexate in conjunction with R-CHOP chemotherapy for eligible patients deemed at a high risk of CNS recurrence, especially those with high-risk CNS-IPI and extra-nodal involvement.

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.

Primary Central Nervous System Lymphoma

PURPOSE OF REVIEW

Primary central nervous system (CNS) lymphoma is a rare and aggressive extranodal non-Hodgkin lymphoma confined to the brain, eyes, spinal cord, or leptomeninges without systemic involvement. This article provides an overview of the clinical features, diagnosis, and management of primary CNS lymphoma in patients who are immunocompetent, focusing on recent advances in treatment.

RECENT FINDINGS

Primary CNS lymphoma is sensitive to radiation therapy; however, whole-brain radiation therapy inadequately controls the disease when used alone and causes delayed neurotoxicity with significant neurocognitive impairment, especially in patients who are elderly. A number of clinical trials have demonstrated durable disease control and less neurotoxicity with methotrexate-based induction chemotherapy with or without autologous stem cell transplantation or reduced-dose whole-brain radiation therapy.

SUMMARY

Prompt diagnosis and initiation of treatment are vital to improving clinical outcomes in patients with primary CNS lymphoma. The optimal treatment has yet to be defined, but high-dose methotrexate-based induction chemotherapy is considered standard for newly diagnosed primary CNS lymphoma. Ongoing randomized trials will attempt to address the roles of rituximab and consolidative treatment using autologous stem cell transplantation or reduced-dose whole-brain radiation therapy. Despite high tumor response rates to initial treatment, many patients will relapse. The choice of salvage treatment will depend on age, previous treatment and response, performance status, and comorbidities at the time of relapse.

The diagnostic role and dynamic changes in cerebrospinal fluid neopterin during treatment of patients with primary central nervous system lymphoma

This study aimed at evaluating the diagnostic and prognostic role of neopterin (Npt) concentration in the cerebrospinal fluid (CSF) of patients with primary central nervous system lymphoma (PCNSL). Ninety‐nine patients were enrolled in this retrospective study; these included patients with PCNSL (n = 21), other brain tumors (n = 44), and inflammatory diseases (n = 34). CSF Npt concentration was measured using ELISA. Receiver operating characteristic (ROC) curve analysis was performed to assess the discriminative ability of CSF Npt concentration for the diagnosis of PCNSL. CSF Npt concentration in patients with PCNSL was significantly higher than that in patients with other brain tumors and inflammatory diseases (P < .001). On ROC curve analysis, the optimal cutoff CSF Npt level of 10.77 ng/mL for the diagnosis of PCNSL and the diagnostic yield of MRI were increased when used in conjunction with CSF Npt concentration. The CSF Npt concentrations in PCNSL patients with multiple lesions were significantly higher than those in patients with a single lesion. Changes in CSF Npt concentration were consistent with post‐treatment changes in tumor sizes. The CSF Npt concentration may be a good biomarker for the diagnosis, for monitoring of disease course, and for prognostic evaluation of patients with PCNSL.

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.

Balancing relapses versus cognitive impairment in primary central nervous system lymphoma: a single-center experience

OBJECTIVES

The outcomes of primary central nervous system lymphoma (PCNSL) are much improved with multi-modality regimens. Unfortunately, in limited-resource countries, chemo-radiotherapy is the only option of curative-intent treatment. This study aimed to evaluate the effects of low-dose whole brain radiotherapy (WBRT) as a consolidation on disease control and long-term neurocognitive functions.

METHODS

We conducted a retrospective single-center study enrolling PCNSL patients from 2011 to May 2016 to evaluate the real-life treatment outcome and neurotoxicity from treatment especially radiotherapy.

RESULTS

Thirty-seven newly diagnosed immunocompetent PCNSL patients were treated with a high-dose methotrexate-based regimen with or without WBRT. The median age was 56 (range 16-78) years old. After chemotherapy, the overall response and complete response (CR) rates were 59.5% and 43.2%, respectively. All 6 partial response (PR) patients and 6 of 16 CR patients underwent radiotherapy. In 22 patients who achieved CR, the progression-free survival (PFS) of patients without WBRT was significantly inferior to the WBRT group with the hazard ratio of 4.7 (95% confidence interval 1.14-19.82, p = 0.03). The 3-year PFS were 35% and 78.75%, respectively, but there was no difference in overall survival. The serial Montreal Cognitive Assessment evaluations (20-72 months post chemotherapy) of 10 long-term CR patients revealed one dementia among three patients without WBRT and five mild cognitive impairments in seven patients with WBRT. Except for the dementia case, all the other patients can perform daily activities without assistance.

CONCLUSION

The low-dose WBRT consolidation is associated with lower PCNSL relapses with only mild neurocognitive toxicity.

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.

Patterns of relapse in primary central nervous system lymphoma: inferences regarding the role of the neuro-vascular unit and monoclonal antibodies in treating occult CNS disease

Background and purpose

The radiologic features and patterns of primary central nervous system lymphoma (PCNSL) at initial presentation are well described. High response rates can be achieved with first-line high-dose methotrexate (HD-MTX) based regimens, yet many relapse within 2 years of diagnosis. We describe the pattern of relapse and review the potential mechanisms involved in relapse.

Methods

We identified 78 consecutive patients who attained complete radiographic response (CR) during or after first-line treatment for newly diagnosed PCNSL (CD20+, diffuse large B cell type). Patients were treated with HD-MTX based regimen in conjunction with blood–brain barrier disruption (HD-MTX/BBBD); 44 subsequently relapsed. Images and medical records of these 44 consecutive patients were retrospectively reviewed. The anatomical location of enhancing lesions at initial diagnosis and at the time of relapse were identified and compared.

Results

37/44 patients fulfilled inclusion criteria and had new measureable enhancing lesions at relapse; the pattern and location of relapse of these 37 patients were identified. At relapse, the new enhancement was at a spatially distinct site in 30 of 37 patients. Local relapse was found only in seven patients.

Discussion

Unlike gliomas, the majority of PCNSL had radiographic relapse at spatially distinct anatomical locations within the brain behind a previously intact neurovascular unit (NVU), and in few cases outside, the central nervous system (CNS). This may suggest either (1) reactivation of occult reservoirs behind an intact NVU in the CNS (or ocular) or (2) seeding from bone marrow or other extra CNS sites.

Conclusion

Recognizing patterns of relapse is key for early detection and may provide insight into potential mechanisms of relapse as well as help develop strategies to extend duration of complete response.

Early whole brain radiotherapy in primary CNS lymphoma: negative impact on quality of life in the randomized G-PCNSL-SG1 trial

PURPOSE

In the randomized G-PCNSL-SG-1 trial, the addition of whole brain radiotherapy (45 Gy) to high-dose methotrexate (HD-MTX)-based chemotherapy (early WBRT arm) did not prolong overall survival (OS) as compared to HD-MTX-based chemotherapy alone (no early WBRT arm) in primary CNS lymphoma (PCNSL) patients. To determine whether WBRT might lead to quality of life (QoL)-relevant late neurotoxicity, this trial prospectively monitored QoL.

METHODS

QoL measurements were performed using the EORTC-QLQ-C30 and BN20 questionnaires and combined with repeated Mini Mental State Examinations (MMSE). Exploratory data analysis included the 318 patients in the per-protocol population.

RESULTS

In year 2 after randomization, cognitive functioning and global health status were reduced in the early WBRT arm as compared to the no early WBRT arm (p = 0.004 and p = 0.022, respectively). Also, fatigue (p = 0.037), appetite loss (p = 0.006) and hair loss (p = 0.002) were more intense in the early WBRT arm. MMSE testing revealed lower values (p = 0.002) in the early WBRT arm. A mixed model analysis of longitudinal data additionally showed differences favoring the no early WBRT arm in 15 of 26 dimensions of QoL.

CONCLUSIONS

The analysis of subjective QoL questionnaires and objective MMSE testing revealed that QoL and cognition were conserved in the arm without early WBRT. Thus, even though it was an exploratory analysis, the results of G-PCNSL-SG1 challenge the place of WBRT in the primary therapy of PCNSL.

Primary Vitreoretinal Lymphoma: Management of Isolated Ocular Disease

BACKGROUND

The prognosis for patients with primary vitreoretinal is dismal. The close association of primary vitreoretinal lymphoma with primary central nervous system lymphoma is responsible for high rates of mortality. Traditional treatments consist of systemic chemotherapy and whole-brain radiotherapy. The optimal approach for the treatment of isolated primary vitreoretinal lymphoma is unclear.

METHODS

A review of the relevant medical and scientific literature was performed, focusing on the clinical features of primary vitreoretinal lymphoma and the progress made in the management of isolated ocular disease.

RESULTS

Ocular treatment options for primary vitreoretinal lymphoma have recently expanded with the addition of intravitreal chemotherapeutic agents and localized radiation. Based on several retrospective reports, a general shift has been made toward local therapy (eg, orbital radiotherapy, intravitreal chemotherapy) for ocular disease. No prospective, randomized clinical trials yet exist to guide therapy.

CONCLUSIONS

Optimal treatment regimens for isolated primary vitreoretinal lymphoma continue to evolve. Further investigations into novel therapies and protocols are needed to decrease recurrence rates, reduce or prevent central nervous system involvement, and improve rates of overall survival.

Phase II Trial of Temsirolimus for Relapsed/Refractory Primary CNS Lymphoma

PURPOSE

In this phase II study (NCT00942747), temsirolimus was tested in patients with relapsed or refractory primary CNS lymphoma (PCNSL).

PATIENTS AND METHODS

Immunocompetent adults with histologically confirmed PCNSL after experiencing high-dose methotrexate-based chemotherapy failure who were not eligible for or had experienced high-dose chemotherapy with autologous stem-cell transplant failure were included. The first cohort (n = 6) received 25 mg temsirolimus intravenously once per week. All consecutive patients received 75 mg intravenously once per week.

RESULTS

Thirty-seven eligible patients (median age, 70 years) were included whose median time since their last treatment was 3.9 months (range, 0.1 to 14.6 months). Complete response was seen in five patients (13.5%), complete response unconfirmed in three (8%), and partial response in 12 (32.4%) for an overall response rate of 54%. Median progression-free survival was 2.1 months (95% CI, 1.1 to 3.0 months). The most frequent Common Toxicity Criteria ≥ 3° adverse event was hyperglycemia in 11 (29.7%) patients, thrombocytopenia in eight (21.6%), infection in seven (19%), anemia in four (10.8%), and rash in three (8.1%). Fourteen blood/CSF pairs were collected in nine patients (10 pairs in five patients in the 25-mg cohort and four pairs in four patients in the 75-mg cohort). The mean maximum blood concentration was 292 ng/mL for temsirolimus and 37.2 ng/mL for its metabolite sirolimus in the 25-mg cohort and 484 ng/mL and 91.1 ng/mL, respectively, in the 75-mg cohort. Temsirolimus CSF concentration was 2 ng/mL in one patient in the 75-mg cohort; in all others, no drug was found in their CSF.

CONCLUSION

Single-agent temsirolimus at a weekly dose of 75 mg was found to be active in relapsed/refractory patients with PCNSL; however, responses were usually short lived.

Rituximab with high-dose methotrexate in primary central nervous system lymphoma

The addition of rituximab (R) to chemotherapy improves outcomes in patients with systemic B-cell non-Hodgkin lymphomas, but the impact in patients with primary central nervous system lymphoma (PCNSL) receiving high-dose methotrexate (HDMTX) is unknown. Patients diagnosed with PCNSL at the British Columbia Cancer Agency (BCCA) between 2000 and 2013 were treated with ≥1 cycle of HDMTX 8 g/m(2) every 2 weeks, to best response or 10 cycles. After 2006, rituximab 375 mg/m(2) was given every 2 weeks with HDMTX for a total of 4 doses. 49 (66%) patients received HDMTX alone and 25 (34%) HDMTX+R, with a median of 5 (range 1-10) HDMTX cycles, and no difference between groups. The median follow-up was 5 years: 8.8 years (range 3.15-13.5 years) HDMTX and 1.9 years (range 0.5-7 years) HDMTX+R. The 5-year PFS was 17%, with no difference between groups (HR: 0.75, 95% CI: 0.41-1.35; P = 0.33). The 5-year OS was 38%, with no difference between the groups OS (HR: 0.73, 95% CI: 0.35-1.52; P = 0.39). In this retrospective study comparing two subgroups of patients treated in different eras, the addition of R to HDMTX did not appear to improve outcomes in PCNSL, possibly consistent with its known poor CNS penetration. It is possible that with a larger sample size, longer follow-up, or different rituximab dosing/schedule, the addition of rituximab may lead to a statistically significant improvement in outcomes. Prospective randomized trials currently in progress will more definitively estimate the impact of the addition of rituximab to HDMTX-based chemotherapy for PCNSL.

Late relapses in primary CNS lymphoma after complete remissions with high-dose methotrexate monotherapy

Treatment of patients with newly diagnosed primary CNS lymphomas using high dose methotrexate regimens is reported to yield about 30% long term survivors with minimal neurotoxicity. As in other systemic large cell lymphomas, it is generally assumed that most relapses occur within 5 years of diagnosis. A retrospective review of the Johns Hopkins experience in 52 patients treated between 1995 and 2008 yielded 19 patients (37%) who achieved a complete response and were followed for over 5 years. Four of these patients remained progression-free for over 10 years. However, two of these long-term survivors have now relapsed over 10 years after their initial diagnosis. An analysis of progression and overall survival does not reveal a plateau suggesting that even patients who have not recurred for over 10 years remain at high risk for relapse after treatment with single agent high dose methotrexate.

[Clinical characteristics and outcome of patients with primary central nervous system lymphoma]

目的

探讨原发中枢神经系统淋巴瘤(PCNSL)的临床特征、治疗方案以及预后相关因素。

方法

回顾性总结北京协和医院自1999年6月至2012年6月收治的37例PCNSL患者临床资料，对患者临床特征、治疗以及预后相关因素进行分析。

结果

全部37例PCNSL患者中位发病年龄57(17~78)岁，男女比为2.7:1。以颅内高压和智能障碍为最常见临床表现，起病至诊断中位时间1.5(1~24)个月。肿瘤累及部位以大脑半球为主，且多灶病变更为常见。36例经治患者无进展生存(PFS)时间为18.0 (95%CI 9.1~26.9)个月，总生存(OS)时间为36.0 (95%CI 21.7~50.3)个月，3年累计OS率为46.9%。放化疗联合治疗与单纯化疗组PFS时间[16.0 (95%CI 8.9~23.1)个月对26.0(95% CI 2.9~49.1)个月]及OS时间[36.0 (95%CI 2.3~69.7)个月对29.0 (95%CI 23.4~34.6)个月]比较，差异均无统计学意义(P=0.401、0.866)。

结论

PCNSL预后不佳，化放疗联合并不能显著改善患者生存，其最佳治疗方案应需进一步探索。

[Clinical and prognostic analysis of 30 cases of primary central nervous system lymphoma]

目的

探讨原发性中枢神经系统淋巴瘤（PCNSL）的临床特征、治疗及预后相关因素。

方法

回顾性分析2006年2月至2014年3月天津医科大学肿瘤医院收治的30例PCNSL患者的临床资料，采用Kaplan-Meier法及Log-rank检验进行生存分析。

结果

30例患者中男14例，女16例，平均年龄57.4(23~81)岁。单发肿瘤18例，多发肿瘤12例。17例主要表现高颅压症状，13例表现为不同程度的局灶性神经系统损害。弥漫大B细胞淋巴瘤13例。60％以上患者接受手术、放疗及化疗联合治疗。所有患者治疗后评价CR率63.3%，中位生存期为24个月，2年生存率为46.7%，5年生存率为13.3%,6个月无进展生存率60.0%，1年无进展生存率为43.3%。其中11例患者接受全脑放疗联合化疗，中位生存期为48个月，7例患者接受立体定向放射外科联合化疗，中位生存期与前者比较差异无统计学意义(P=0.233)。单因素生存分析提示年龄与生存期相关(P=0.030)。

结论

PCNSL以弥漫大B细胞淋巴瘤多见，可表现为单发或多发，临床表现为颅内高压或局部神经系统损害。年龄是生存期的重要相关因素。手术治疗适用于幕上、位置表浅肿瘤及急性高颅压患者。立体定向放射外科治疗可迅速缓解症状，神经毒性小，是可行的局部治疗手段。多模式治疗的结合更能使患者获益。

Stereotactic radiosurgery in combination with up-front high-dose methotrexate as a first-line treatment for newly diagnosed primary central nervous system lymphoma

The efficacy of stereotactic radiosurgery (SRS) instead of whole brain radiotherapy (WBRT) following high-dose methotrexate (HD-MTX) for primary central nervous system lymphoma (PCNSL) is unclear. To clarify whether SRS in combination with up-front HD-MTX supplements the effect of HD-MTX in remaining or refractory lesions after initial HD-MTX treatment. The authors conducted a retrospective review for newly diagnosed PCNSL patients who underwent SRS after HD-MTX as a first-line treatment. The local control (LC), the progression-free survival (PFS), the recurrence patterns, the salvage treatments, the overall survival (OS), the Karnofsky Performance Status (KPS), the activities of daily living (ADL) were analyzed as well as radiosurgical parameters. Twenty patients underwent SRS for 51 lesions with the median volume of 0.45 cm(3). The median age at SRS was 67 (range 37-82). The median KPS at SRS was 90. The LC rate at 2 years was 86.0 %, the median PFS after SRS was 17 months, necessitating additional SRS and chemotherapy. The median OS was 52 months. No significant side effects related to SRS were observed. During follow-up period, the good ADL preservation was achieved for 13 months from SRS. Patients with KPS ≥ 90 at SRS demonstrated longer ADL preservation (32 months from SRS). SRS following up-front HD-MTX without WBRT provided excellent LC, acceptable OS and the long ADL preservation period. These benefits may be more emphasized especially in patients with good KPS, but should be validated in a large patient population.

[Leptomeningeal infiltlation of primary CNS B-cell lymphoma diagnosed by the biopsy of cauda equina: a case report]

A 49-year-old man was admitted to our hospital with progressive gait disturbance. Our examination revealed a low grade fever, weight loss derived muscle weakness, sensory disturbance and loss of deep tendon reflex of the lower extremities. Magnetic resonance imaging (MRI) detected an abnormal intensity and gadolinium enhancement in the cauda equina. Two weeks after admission, disturbance of consciousness and bladder appeared. Cerebrospinal fluid examination showed pleocytosis, elevated protein and soluble IL-2R, but cytological examination was class II negative. We performed a cauda equina biopsy urgently and diagnosed malignant lymphoma, of a diffuse large B-cell type. We selected combined MTX-based chemoradiotherapy and his symptoms significantly improved after a month. He achieved complete remission and remains recurrence-free after 10 months post treatment although he remains with light paraparesis and sensory disturbance of the lower extremities. He has already gone back to a normal life. An examination of cauda equina biopsy led to quick diagnosis and treatment.

Upfront autologous stem-cell transplantation with melphalan, cyclophosphamide, etoposide, and dexamethasone (LEED) in patients with newly diagnosed primary central nervous system lymphoma

Treatment of primary central nervous system lymphoma (PCNSL) improved in recent years. However, the high neurotoxicity and low survival rates associated with this condition remain unresolved. We report 13 consecutive patients with PCNSL for whom upfront melphalan, cyclophosphamide, etoposide, and dexamethasone (known as LEED) followed by autologous stem-cell transplantation (ASCT) was planned at the Anjo Kosei Hospital. All patients were pathologically diagnosed with diffuse large B-cell lymphoma and were negative for human immunodeficiency virus. All patients were to receive three cycles of high-dose methotrexate-based induction chemotherapy, two cycles of high-dose AraC-based chemotherapy, and LEED followed by ASCT. All 13 patients achieved a partial response, and the 3-year overall survival (OS) rate was 76.2 %. Seven of the 13 patients were alive at the last follow-up, without any adverse events, including neurotoxicity. Six of the 13 (46.2 %) patients underwent ASCT and the 3-year OS rate was 80.0 %. Although this study included only a limited number of patients, these preliminary signs of efficacy and tolerability merit further consideration. To make further improvements in survival, the rate of patients undergoing ASCT should be increased. Other prospective studies involving greater numbers of patients are required to confirm these findings.

Combined modality therapy versus chemotherapy alone as an induction regimen for primary central nervous system lymphoma: a cost-effectiveness analysis

BACKGROUND

In immunocompetent patients with primary central nervous system lymphoma (PCNSL), combined modality therapy (CMT) using high-dose methotrexate and radiotherapy (WBRT) has improved response rates compared with chemotherapy alone. The trade-off is delayed and potentially devastating treatment-related neurotoxicity (NT).

METHODS

A cost-effectiveness analysis using a Markov model compared CMT with chemotherapy alone in age-stratified patients with PCNSL. Baseline probabilities were derived from a systematic literature review. Direct and lost productivity costs were collected from a Canadian perspective and presented in Can$ in 2011. Outcomes were life expectancy, quality-adjusted life years (QALYs), and incremental cost-effectiveness ratio.

RESULTS

The quality-adjusted life expectancy was 1.55 QALYs for CMT and 1.53 QALYs for chemotherapy alone. In younger patients (aged <60 years), CMT yielded 2.44 QALYs, compared with 1.89 QALYs for chemotherapy alone, yielding an expected benefit with CMT of 0.55 QALYs or 6.6 quality-adjusted months. The CMT strategy dominated in younger patients, as it was Can$11 951 less expensive than chemotherapy alone. The chemotherapy-alone strategy dominated in older patients, as it was Can$11 244 less expensive than CMT, and there was no difference in QALYs between the strategies. The model was robust in sensitivity analyses of key variables tested through the plausible ranges obtained from costing sources and published literature.

CONCLUSION

The preferred induction strategy for younger patients with PCNSL appears to be CMT, which minimized cost while maximizing life expectancy and QALYs. This analysis confirms that the preferred strategy for older patients is chemotherapy alone.