The Real-World status and risk factors for a poor prognosis in elderly patients with primary central nervous system malignant lymphomas: a multicenter, retrospective cohort study of the Tohoku Brain Tumor Study Group

BACKGROUND

Elderly patients with primary central nervous system malignant lymphoma (EL-PCNSL) may not be given sufficient treatment due to their poor pre-treatment Karnofsky Performance Status (KPS) and comorbidities. Therefore, a retrospective, cohort study was performed to evaluate risk factors associated with a poor prognosis of EL-PCNSL in the Tohoku Brain Tumor Study Group.

METHODS

Patients aged ≥ 71 years with PCNSL were enrolled from eight centers. Univariate analysis was performed with the log-rank test. A Cox proportional hazards model was used for multivariate analysis.

RESULTS

Three of the total 142 cases received best supportive care (BSC). Treatment was given to 30 cases without a pathological diagnosis, 3 cases with cerebrospinal fluid (CSF) cytology, and 100 cases with a pathological diagnosis. After confirmation of no differences in progression-free survival (PFS) and overall survival (OS) between the group treated without pathology and the groups diagnosed by pathology or CSF cytology and between median age ≥ 76 years and < 76 years, a total of 133 patients were studied. The median pre-treatment KPS was 50%. Median PFS and median OS were 16 and 24 months, respectively. Risk factors associated with poor prognosis on Cox proportional hazards model analysis were pre-treatment cardiovascular disease and central nervous system disease comorbidities, post-treatment pneumonia and other infections, and the absence of radiotherapy or chemotherapy.

CONCLUSIONS

Pre-treatment comorbidities and post-treatment complications would affect the prognosis. Radiation and chemotherapy were found to be effective, but no conclusions could be drawn regarding the appropriate content of chemotherapy and whether additional radiotherapy should be used.

Treatment Regimens for Immunocompetent Elderly Patients with Primary Central Nervous System Lymphoma: A Scoping Review

Simple Summary

Most patients diagnosed with primary central nervous system lymphoma (PCNSL) are 60 years or older and tend to have a poor prognosis. Evidence to guide and optimize treatment choices for these vulnerable patients is limited. We performed a scoping review to identify and describe all relevant clinical studies investigating chemotherapies and combinations of chemotherapies (including high-dose chemotherapy followed by autologous stem cell transplantation (HCT-ASCT)) in elderly PCNSL patients. In total, we identified six randomized controlled trials, 26 prospective and 24 retrospective studies (with/without control group). While most studies investigated protocols based on ‘conventional’ chemotherapy treatment, data evaluating HCT-ASCT in the elderly were scarce, and the generalizability of the only RCT published is questionable. Considering the poor prognosis of these patients and their need for more effective treatment options, a thoroughly planned randomized controlled trial comparing HCT-ASCT with ‘conventional’ chemoimmunotherapy is urgently needed to evaluate the efficacy of HCT-ASCT.

Abstract

Background: Most patients diagnosed with primary central nervous system lymphoma (PCNSL) are older than 60 years. Despite promising treatment options for younger patients, prognosis for the elderly remains poor and efficacy of available treatment options is limited. Materials and Methods: We conducted a scoping review to identify and summarize the current study pool available evaluating different types and combinations of (immuno) chemotherapy with a special focus on HCT-ASCT in elderly PCNSL. Relevant studies were identified through systematic searches in the bibliographic databases Medline, Web of Science, Cochrane Library and ScienceDirect (last search conducted in September 2020). For ongoing studies, we searched ClinicalTrials.gov, the German study register and the WHO registry. Results: In total, we identified six randomized controlled trials (RCT) with 1.346 patients, 26 prospective (with 1.366 patients) and 24 retrospective studies (with 2.629 patients). Of these, only six studies (one completed and one ongoing RCT (with 447 patients), one completed and one ongoing prospective single arm study (with 65 patients), and two retrospective single arm studies (with 122 patients)) evaluated HCT-ASCT. Patient relevant outcomes such as progression-free and overall survival and (neuro-)toxicity were adequately considered across almost all studies. The current study pool is, however, not conclusive in terms of the most effective treatment options for elderly. Main limitations were (very) small sample sizes and heterogeneous patient populations in terms of age ranges (particularly in RCTs) limiting the applicability of the results to the target population (elderly). Conclusions: Although it has been shown that HCT-ASCT is probably a feasible and effective treatment option, this approach has never been investigated within a RCT including a wide range of elderly patients. A RCT comparing conventional (immuno) chemotherapy with HCT-ASCT is crucial to evaluate benefit and harms in an un-biased manner to eventually provide older PCNSL patients with the most effective treatment.

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.

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.

Clinical significance of disease-specific MYD88 mutations in circulating DNA in primary central nervous system lymphoma

Recent sequencing studies demonstrated the MYD88 L265P mutation in more than 70% of primary central nervous system lymphomas (PCNSL), and the clinical significance of this mutation has been proposed as diagnostic and prognostic markers in PCNSL. In contrast, mutational analyses using cell-free DNAs have been reported in a variety of systemic lymphomas. To investigate how sensitively the MYD88 L265P mutation can be identified in cell-free DNA from PCNSL patients, we carried out droplet digital PCR (ddPCR) and targeted deep sequencing (TDS) in 14 consecutive PCNSL patients from whom paired tumor-derived DNA and cell-free DNA was available at diagnosis. The MYD88 L265P mutation was found in tumor-derived DNA from all 14 patients (14/14, 100%). In contrast, among 14 cell-free DNAs evaluated by ddPCR (14/14) and TDS (13/14), the MYD88 L265P mutation was detected in eight out of 14 (ddPCR) and in 0 out of 13 (TDS) samples, implying dependence on the detection method. After chemotherapy, the MYD88 L265P mutation in cell-free DNAs was traced in five patients; unexpectedly, the mutations disappeared after chemotherapy was given, and they remained undetectable in all patients. These observations suggest that ddPCR can sensitively detect the MYD88 L265P mutation in cell-free DNA and could be used as non-invasive diagnostics, but may not be applicable for monitoring minimal residual diseases in PCNSL.

A single institutional retrospective evaluation for younger patients with primary central nervous lymphomas on a modified R-MPV regimen followed by radiotherapy and high dose cytarabine

We conducted a retrospective analysis of patients younger than 60 years (N = 10, median age 54.5) with newly diagnosed primary central nervous system lymphoma (PCNSL) at the University of Tsukuba Hospital from January 2008 to November 2016. All the patients were scheduled to receive a single regimen without registration to any clinical trials. This was based on a phase 2 study by Memorial Sloan-Kettering Cancer Center (MSKCC); induction chemotherapy with rituximab, methotrexate, procarbazine, and vincristine (R-MPV) (five to seven cycles), followed by whole-brain radiotherapy (rd-WBRT) (23.4 Gy) and two high-dose cytarabine (HD-AC) cycles as a consolidation. The median age was 54.5 years, and median follow up duration was 33.1 months. The 3-year overall survival (OS) and progression-free survival (PFS) were 69% (95% CI 31-89%) and 56% (95% CI 20-81%). The median OS and PFS were not reached, respectively. Acute and delayed toxicities were manageable. In particular, OS and PFS of seven patients who achieved CR by the R-MPV induction chemotherapy were significantly superb (3-year OS, 100%; 3-year PFS, 80%), implying that a large proportion of patients in CR after the completion of this treatment may achieve durable disease control. On the other hand, all of the three patients who had progressive disease during this treatment died of disease progression within 1 year after diagnosis without achieving CR. Identifying the patients having a risk of failure in the R-MPV induction chemotherapy is important, and may allow us to consider a potentially more effective regimen.

Pemetrexed for primary central nervous system lymphoma in the elderly

OBJECTIVE

The aim of this study was to evaluate the efficacy and safety of a consecutive series of elderly patients with primary central nervous system lymphoma (PCNSL) treated with single-agent pemetrexed without radiotherapy or intrathecal chemotherapy.

METHODS

Twelve histologically confirmed newly diagnosed PCNSL patients older than 65 years were studied between 2008 and 2013. An induction chemotherapy was initially given (pemetrexed 600 mg/m(2) on day 1, every 3 weeks). Patients achieving a complete, partial response or stable disease proceeded to a maintenance phase (up to 6 cycles). Patients with progressive/recurrent disease (PD) were treated with whole brain radiotherapy on an individual basis.

RESULTS

Four patients presented complete response, six patients showed partial response and two patients presented progressive disease. The median progression-free survival (PFS) was 9.0 months [95 % confidence interval (CI) 2.0-45.3] and the median overall survival was 19.5 months (95 % CI 5.0-45.3). Adverse events included leukocytopenia, anemia, fatigue, rash and vomiting. No neurotoxicity or treatment-related death was observed. The estimated 1-year and 2-year survival rate was 66.7 and 41.7 %, respectively.

CONCLUSIONS

Our efficacy results demonstrate that the single-agent pemetrexed was feasible, active and well tolerated in elderly patients with PCNSL. Furthermore, this single-agent regimen results in higher response rates and less toxicity comparable with other chemotherapy or radiotherapy regimens. Prospectively, controlled studies are warranted to confirm such results.

First-line treatment and outcome of elderly patients with primary central nervous system lymphoma (PCNSL)--a systematic review and individual patient data meta-analysis

BACKGROUND

To investigate prognosis and effects of first-line therapy in elderly primary central nervous system lymphoma (PCNSL) patients.

PATIENTS AND METHODS

A systematic review of studies about first-line therapy in immunocompetent patients ≥60 years with PCNSL until 2014 and a meta-analysis of individual patient data from eligible studies and international collaborators were carried out.

RESULTS

We identified 20 eligible studies; from 13 studies, we obtained individual data of 405 patients, which were pooled with data of 378 additional patients (N = 783). Median age and Karnofsky Performance Score (KPS) was 68 years (range: 60-90 years) and 60% (range: 10%-100%), respectively. Treatments varied greatly, 573 (73%) patients received high-dose methotrexate (HD-MTX)-based therapy. A total of 276 patients received whole-brain radiotherapy (median 36 Gy, range 28.5-70 Gy). KPS ≥ 70% was the strongest prognostic factor for mortality [hazard ratio (HR) 0.50, 95% confidence interval (CI) 0.41-0.62]. After a median follow-up of 40 months, HD-MTX-based therapy was associated with improved survival (HR 0.70, 95% CI 0.53-0.93). There was no difference between HD-MTX plus oral chemotherapy and more aggressive HD-MTX-based therapies (HR 1.39, 95% CI 0.90-2.15). Radiotherapy was associated with an improved survival, but correlated with an increased risk for neurological side-effects (odds ratio 5.23, 95% CI 2.33-11.74).

CONCLUSIONS

Elderly PCNSL patients benefit from HD-MTX-based therapy, especially if combined with oral alkylating agents. More aggressive HD-MTX protocols do not seem to improve outcome. WBRT may improve outcome, but is associated with increased risk for neurological side-effects. Prospective trials for elderly PCNSL patients are warranted.