For which patients with aggressive non-Hodgkin's lymphoma is prophylaxis for central nervous system disease mandatory?

Purpose: Data of a multicenter study in non-Hodgkin's lymphoma (NHL) by the Dutch Hovon Group were reanalyzed to assess the risk of relapse in the central nervous system (CNS) related to the international risk index for NHL. In addition we assessed the risk for CNS disease in relation to the presence of bone marrow localisation at presentation.Design: We focused our analysis on those patients reaching a complete remission (CR). Two hundred eighty-six patients (histological subtypes D–H Working Formulation) and with stages II–IV were analyzed. One hundred ninety-three (67%) patients reached a CR.Results: Relapse occurred in 78 patients of whom 10 patients with concomitant or isolated CNS disease. According to the international risk index the following observations were made: low risk (n = 38) nine out of 34 CR relapsed, none had CNS involvement; low-intermediate risk (n = 115) 27 out of 83 CR relapsed, three had CNS involvement; high-intermediate risk (n = 110) 37 out of 68 CR relapsed, six had CNS involvement; high risk (n = 22) four out of seven CR relapsed, one had CNS involvement. Two out of 10 developed isolated CNS disease and eight out of 10 patients developed CNS disease with systemic relapse.Conclusion: Our data show that the number of CNS relapses after CR is relatively low (10 out of 193 = 5%), with an increasing incidence in the high-risk groups according to the international risk index. The occurrence of CNS relapse seems to be related to the risk of systemic relapse after CR. No subgroup could be discriminated in which prophylactic treatment would be of substantial benefit.     

Characteristics and outcomes of elderly patients with primary central nervous system lymphoma

BACKGROUND:

Approximately 50% of all patients with primary central nervous system lymphoma (PCNSL) are aged ≥65 years; however, this group is relatively understudied, and to the authors's knowledge, optimal treatment for older patients is not well defined.

METHODS:

This was a retrospective review of PCNSL patients aged ≥65 years who were treated at Memorial Sloan‐Kettering Cancer Center between 1986 and 2008. A multivariate analysis of demographic and clinical variables on prognosis and receipt of treatment was performed.

RESULTS:

One hundred seventy‐four patients between the ages of 65 and 89 years were identified; there was a slight predominance of women (52.9%). One hundred forty‐eight patients were treated with chemotherapy at the time of diagnosis (98% with methotrexate‐based therapy) and 31 of these patients also received whole‐brain radiotherapy (WBRT). Sixteen patients received WBRT alone. A radiographic response to chemotherapy was noted in 76% of patients. Ninety patients developed disease progression after initial treatment; 74 received salvage therapy and 48% of these patients responded to salvage treatment. The median overall survival was 25 months (range, 18‐33 months), and the 3‐year survival rate was 36%. Approximately 20.1% of patients were alive for ≥11 years. WBRT was delivered more frequently before 1998, and patients with a history of prior malignancy were less likely to receive WBRT. Age and performance status were identified as the most important predictors of survival. Treatment‐related neurotoxicity at 2 years was strongly associated with receipt of WBRT (P = .0002).

CONCLUSIONS:

PCNSL in the elderly remains sensitive to methotrexate‐based chemotherapy and aggressive treatment may be warranted both at the time of diagnosis and disease recurrence. Cancer 2010. © 2010 American Cancer Society.     

Incidence and risk factors for central nervous system occurrence in elderly patients with diffuse large-B-cell lymphoma: influence of rituximab.

BACKGROUND: The incidence of secondary central nervous system (CNS) occurrences in diffuse large-B-cell lymphoma is not sufficiently high to warrant the use of CNS prophylaxis in all patients. The addition of rituximab increases the complete response rate and prolongs event-free and overall survival in elderly patients with such lymphoma. PATIENTS AND METHODS: We analyzed a cohort of 399 elderly patients with lymphoma prospectively treated with eight cycles of CHOP with or without rituximab in order to assess if rituximab decreases the risk of CNS localization. Prophylaxis of CNS disease was not part of the treatment protocol. RESULTS: We observed 20 CNS occurrences: 12 on therapy, four after partial remission and four following complete remission. In three patients, the CNS was the only site of relapse. In a multivariate analysis, increased age-adjusted International Prognostic Index (IPI) was the only independent predictive factor of CNS recurrence. Only three of 20 patients are alive with a follow-up of 24 months. CONCLUSIONS: Rituximab did not influence the risk of CNS occurrence, possibly because of low rituximab diffusion. Direct intrathecal administration of rituximab could overcome this problem. We also confirmed that CNS occurrence is related to IPI as well as very poor prognosis of relapses occurring on therapy.     

Central nervous system involvement in indolent lymphomas.

BACKGROUND: Central nervous system (CNS) involvement, a well-recognized complication of aggressive non-Hodgkin's lymphomas (NHL), has rarely been reported in indolent lymphomas. Large series have reported this complication in 3% of indolent NHLs, generally following histological transformation. PATIENTS AND METHODS: We retrospectively reviewed the disease characteristics and clinical course in seven patients (six females, one male) with indolent B-cell lymphomas who developed CNS involvement during various stages of their illness. RESULTS: The median ages at diagnosis of systemic and CNS lymphoma were 60 and 63 years, respectively. Histologies were: small lymphocytic lymphoma (two), follicular lymphoma grade I (two), follicular lymphoma grade II (two) and unclear low-grade histology (one). There were diverse neurological symptoms. Two patients had parenchymal involvement, three had leptomeningial involvement and two had both. Systemic lymphoma was found in all patients, all but one having bone marrow involvement. Four patients had a transformation to high-grade histology. Six patients were treated with systemic and intra-cerebrospinal fluid chemotherapy, and two received radiotherapy as well. Five patients achieved CNS response. Survival was 1-9 years for treated patients (median 2 years). Three patients died of CNS disease. CONCLUSIONS: CNS involvement is a rare and unexpected complication of indolent NHL, which should be considered in the differential diagnosis of patients presenting with new neurological signs. This condition is treatable and some patients have a long clinical course.     

Central nervous system dissemination in immunocompetent patients with aggressive lymphomas: incidence,risk factors and therapeutic options

Central nervous system (CNS) dissemination is a rare (4–5%) but usually fatal complication of aggressive lymphomas. Prophylaxis modalities to prevent CNS dissemination in aggressive lymphomas cannot be widely applied to every lymphoma patient since it is associated with increased risk of neurotoxicity. Therefore, identification of high‐risk patients as the best candidates to receive CNS prophylaxis constitutes a major endpoint in the management of these malignancies. Various risk factors and models for CNS recurrence have been described. Parameters reflecting the extent and proliferation of the disease, like elevated serum lactate dehydrogenase levels, involvement of multiple extranodal sites, advanced stage and high age‐adjusted International Prognostic Index (IPI) score, as well as the involvement of specific anatomic sites, like testes, orbit, paranasal sinuses, have been identified and confirmed as important to predict CNS dissemination. Management of this complication in aggressive lymphomas with conventional‐dose chemotherapy is associated with disappointing results, while some preliminary but encouraging experiences suggest a potential role of high‐dose chemotherapy and stem cell transplantation. The analysis of recent clinical studies could lead to advancement in the prognosis of aggressive lymphomas, but several questions regarding the optimum chemotherapy combination, the best conditioning regimen and the role of radiation therapy and intrathecal chemotherapy remain still unanswered. The purposes of the present review are to critically analyse current data on the risk of CNS dissemination in aggressive lymphomas, the clinical presentation of secondary CNS lymphomas and the efficacy of CNS prophylaxis as well as to discuss the available therapeutic options for this devastating event. Copyright © 2009 John Wiley & Sons, Ltd.     

Central nervous system involvement in mantle cell lymphoma.

BACKGROUND: Extranodal involvement, including central nervous system (CNS), is a frequent event in patients with mantle cell lymphoma (MCL). However, the incidence, risk factors, and impact on outcome remain controversial. PATIENTS AND METHODS: Main clinical, biological, and evolutive features of 82 patients (60 males/22 females; median age: 61 years) diagnosed with MCL (blastoid, 26%) in a single institution were analyzed for risk of CNS involvement and prognosis. RESULTS: Most patients had advanced stage and intermediate or high-risk International Prognostic Index (IPI). Eleven patients eventually developed CNS involvement with an actuarial 5-year risk of 26% (95% confidence interval 10% to 42%). In one asymptomatic patient, cerebrospinal fluid infiltration was detected at staging maneuvers (1/62; 1.6%). The remaining 10 patients developed neurological symptoms during the course of the disease (median time from diagnosis, 25 months). Initial variables predicting CNS involvement were blastoid histology, high proliferative index measured by Ki-67 staining, high lactate dehydrogenase (LDH) and intermediate- or high-risk IPI. Histological subtype and serum LDH maintained significance in multivariate analysis. Treatment of CNS infiltration consisted of intrathecal chemotherapy (two cases), and intrathecal chemotherapy plus systemic treatment (seven cases). Median survival after CNS involvement was 4.8 months, patients with this complication having shorter survival than those with no CNS disease. CONCLUSION: This study confirms the high incidence of CNS involvement in MCL patients. Treatments aimed at preventing this complication are warranted.     

Pegfilgrastim to support CHOP-14 in elderly patients with non-Hodgkin's lymphoma

This study investigated whether pegfilgrastim support would enable on-schedule delivery of dose-dense cyclophosphamide, doxorubicin, vincristine and prednisone (CHOP-14) to elderly patients with non-Hodgkin's lymphoma (NHL). Thirty patients 60 years of age and older with aggressive NHL were evaluated after receiving up to six cycles of CHOP-14 supported with pegfilgrastim. The median age was 68 years (range 61 - 74). Forty-seven per cent of patients received full dose chemotherapy on schedule for all cycles (range 65 - 93). Chemotherapy was delayed in 10 patients and dose reduced in 15 patients. Hematological toxicity was the most common reason for delays and dose reduction. Six of nine patients (67%) achieved a peripheral blood CD34⁺ count of at least 20 cells×10⁶ L^-1 on day 12 of cycle one. The delivery on schedule of dose-dense CHOP-14 to elderly patients with previously untreated aggressive NHL is safe and efficacious with once per cycle pegfilgrastim support.     

Central nervous system involvement following diagnosis of non-Hodgkin's lymphoma: a risk model.

BACKGROUND: To determine the incidence and risk factors for central nervous system (CNS) relapse in patients with non-Hodgkin's lymphoma (NHL). PATIENTS AND METHODS: Patient records were registered prospectively in successive patients with NHL admitted to the Norwegian Radium Hospital from 1980 to 1996. A total of 2514 patients had no CNS involvement at diagnosis and were treated according to standard protocols. The incidence and risk factors for CNS progression or relapse were examined retrospectively. RESULTS: In low-grade (L)-NHL, the risk of CNS involvement was low (2.8%). In high-grade (H)-NHL, lymphoblastic and Burkitt's NHL patients had a high risk of CNS recurrence (24.4%) at 5 years, and prophylaxis seemed to reduce this risk. For the other patients with H-NHL, the proportion with CNS involvement at 5 years was 5.2%. Multivariate analysis identified five independent risk factors, each present in >5% of patients: elevated serum lactate dehydrogenase, serum albumin <35 g/l, <60 years of age, retroperitoneal lymph node involvement and involvement of more than one extranodal site. If four or five of these risk factors were present, the risk of CNS recurrence was in excess of 25% at 5 years. CONCLUSIONS: The risk of CNS involvement in this study is comparable with the results from other large series. CNS prophylaxis is not recommended in any subgroup of L-NHL. The risk of CNS involvement among patients with either Burkitt's or lymphoblastic lymphomas is considerable and these patients should therefore receive intensive chemotherapy including systemic and intrathecal methotrexate. Patients with other types of H-NHL should receive adequate CNS prophylaxis if at least four of the five risk factors identified are present.     

Incidence and risk factors for central nervous system relapse in patients with primary mediastinal large B-cell lymphoma in the rituximab era

Central nervous system (CNS) involvement is rare in primary mediastinal large B-cell lymphoma (PMLBCL). We aimed to evaluate the incidence of CNS relapse as first treatment failure event and the effect of the induction chemotherapy regimen, central nervous system - international prognostic index (CNS-IPI) and other clinical and laboratory variables on the risk of CNS relapse in 564 PMLBCL patients treated with immunochemotherapy. Only 17 patients (3.0%) received CNS prophylaxis. During a 55-month median follow-up only 8 patients experienced CNS relapse as first event, always isolated. The 2-year cumulative incidence of CNS relapse (CI-CNSR) was 1.47% and remained unchanged thereafter. The CI-CNSR was not affected by the chemotherapy regimen (R-CHOP or R-da-EPOCH). None of the established International Prognostic Index factors for aggressive lymphomas predicted CNS relapse in PMLBCL. The 2-year CI-CNSR in patients with versus without kidney involvement was 13.3% versus 0.96% (p < 0.001); 14.3% versus 1.13% with versus without adrenal involvement (p < 0.001); and 10.2% versus 0.97% with versus without either kidney or adrenal involvement. CNS-IPI was also predictive (2-year CI-CNSR in high-risk vs. intermediate/low-risk: 10.37% vs. 0.84%, p < 0.001). However, this association may be driven mainly by kidney and/or adrenal involvement. In conclusion, in PMLBCL, CNS relapse is rare and appears to be strongly associated with kidney and/or adrenal involvement.     

Patterns of treatment in older adults with primary central nervous system lymphoma

BACKGROUND: The incidence of primary central nervous system lymphoma (PCNSL) has increased in recent decades and is highest in people aged >or=65 years. Radiotherapy (XRT) and systemic chemotherapy (CTX), alone or in combination, are reported to extend survival, but treatment-related toxicity is a particular concern in the elderly. The objective of the current study was to identify factors associated with the receipt and type of treatment in a population-based cohort of older PCNSL patients. METHODS: Using Surveillance, Epidemiology, and End Results (SEER) cancer registry data linked with Medicare claims, the authors identified PCNSL cases in adults aged >or=65 years who were diagnosed between 1994 and 2002. Initial treatment was defined as XRT alone, CTX alone, combined CTX and XRT, or no treatment, based on Medicare claims in the 6 months after diagnosis. The authors assessed the effects of age, comorbidity, and sociodemographic characteristics on the odds of receiving treatment. RESULTS: Of 579 PCNSL patients, 464 (80%) received any treatment. XRT alone was the most common modality (46%), followed by combined therapy (33%) and CTX alone (22%). The type of treatment varied by age (P < .0001). The use of CTX alone or in combination with XRT decreased with increasing age, whereas the use of XRT alone increased with age. In adjusted analysis, younger age (P < .01) was found to be predictive of the receipt of any treatment. The use of CTX decreased with age (P < .0001). The median survival was 7 months (95% confidence interval, 6-8 months); no significant time trends were observed. CONCLUSIONS: Although the majority of older PCNSL patients received treatment, most did not receive optimal therapy. Age was found to have the greatest influence on treatment selection. Overall survival in elderly PCNSL patients appears to be poor.     

Second malignancies in patients with primary central nervous system lymphoma

Background

Primary central nervous system lymphoma (PCNSL) is a rare extranodal lymphoma with distinctive biological behaviors. The evolving treatment of PCNSL has greatly improved the outcome for patients with this disease and has stimulated interest in second malignancies (SMs) in patients diagnosed with PCNSL.

Methods

The records of 129 cases of PCNSL at Mayo Clinic, diagnosed between January 1, 1988, and November 26, 2012, were reviewed. Data on clinical characteristics, laboratory parameters, treatments, outcomes, and SMs were collected. The mean follow-up time was 44.8 months (range, 0.5–240 months; median, 28.0 months).

Results

Altogether, 28 cases with 30 (23.26%) SMs were identified. Twenty (15.50%) patients had prior or synchronous SM. Ten (7.76%) patients developed a subsequent primary cancer after PCNSL. The most common sites of prior or synchronous SMs were prostate (4/20), skin (4/20), and gastrointestinal (3/20). The most common site of the subsequent SM was skin (4/10). Two cases were identified with both prior SM and subsequent SM.

Conclusions

Second malignancies in cases with PCNSL were not uncommon and occurred in nearly a quarter of our cohort. Nonmelanoma skin cancers were frequently seen. Therefore, screening for SMs should also be considered in long-term follow-up of patients with PCNSL. In addition, the high incidence of subsequent cancer, synchronous cancer, and frequently seen nonmelanoma skin cancers may all indicate an immunosuppressed state in patients with PCNSL.     

Primary central nervous system lymphoma in immunocompetent patients: a retrospective review of MRI features

Introduction: To define the features of primary central nervous system lymphoma (PCNSL) on MRI in immunocompetent patients. Methods: A retrospective review of the authors' institutional database was performed to identify histologically proven cases of PCNSL. Images were retrieved and reviewed with respect to location, lesion number, size, signal intensity, enhancement characteristics, oedema and necrosis. Results: Thirty‐one cases of histologically proven PCNSL had available imaging. One patient was excluded due to immunosuppression. Of the 30 remaining cases, the average age was 65.5 years, and males and females were equally represented. A total of 68 lesions (average of 2.5 per patient) were identified. With diffusion‐weighted imaging, all but two had restricted diffusion (40.3% mild and 55.6% marked) and all but one had enhancement (51.5% homogeneous, 42.6% heterogeneous and ring 4.4%). Most lesions were isointense to grey matter (75.8% on T2‐weighted image (WI) and 82.5% on T1‐WI). Oedema was mild in 43.4% and marked in 55.2%. Necrosis was seen in only five lesions (7.4%). On a per patient basis, 50% had bilateral lesions and 96.7% had lesions contacting a cerebrospinal fluid (CSF) surface. 16.7% of patients had posterior fossa involvement and 30% had lesions in the basal ganglia or thalami. Conclusion: The vast majority of cases of PCNSL in immunocompetent patients have lesions contacting a CSF surface, enhancement and restricted diffusion with no necrosis. These features should alert radiologists to the diagnosis of PCNSL.     

Proton magnetic resonance spectroscopy in immunocompetent patients with primary central nervous system lymphoma

Background: Magnetic resonance spectroscopy imaging (MRSI) non-invasively evaluates the metabolic profile of normal and abnormal brain tissue. Primary central nervous system lymphoma (PCNSL) is a highly aggressive tumor responsive to high-dose methotrexate based regimens. Patients often have complete responses but relapses are common. We characterized the MR spectra of PCNSL patients, correlated MRSI with MRI and evaluated whether early recurrence could be detected by MRSI.Methods: Patients with PCNSL had multi-voxel MRSI before, during, and after treatment. The region of interest was defined using axial FLAIR images. Metabolites assessed were N-acetyl-aspartate (NAA), choline (Cho), creatine (Cr), lipid, and lactate. Ratios of Cho/Cr, NAA/Cho, and NAA/Cr were calculated and correlated with MRI. Overall survival (OS), progression free survival (PFS), and relative risks of each of the ratios were determined.Results: MRSI was performed on 11 men and seven women; median age of 59. Sixty-seven MRSI studies were performed, 17 baseline and 48 follow-up studies. Median ratios in 16 pretreated patients were Cho/Cr-1.90, NAA/Cho-0.39, and NAA/Cr-1.27. Two patients had lipid at baseline, five had lactate and two had both. MRSI correlated with tumor response or progression on MRI; in three patients MRSI suggested disease progression prior to changes on MRI. Univariate analysis of metabolite ratios, lipid, and lactate revealed that none significantly affected PFS or OS. Kaplan–Meier analysis of the presence or absence of lipid, lactate or both revealed a trend for increased PFS.Conclusion: MRSI and MRI correlate with tumor response or progression and may allow early detection of disease recurrence. The presence or absence of lipid and/or lactate may have prognostic significance. Further research using MRSI needs to be done to validate our findings and determine the role of MRSI in PCNSL.Presented in part at the 1999 Annual Meeting of the American Academy of Neurology; April 12, 1999.     

原发性中枢神经系统淋巴瘤35例临床及预后分析

目的：探讨原发中枢神经系统淋巴瘤（PCNSL）临床特点、诊治方案及临床疗效。方法：总结2001年1月-2008年1月收治的35例PCNSL患者,均经病理证实为B细胞来源非霍奇金淋巴瘤并接受放疗,其中25例放疗后接受化疗。结合文献对原发性中枢神经系统淋巴瘤患者的临床特点、病理学检查、影像学表现、治疗及预后进行回顾性分析。结果：本病以中老年人多见,发病急,病程短,病情进展快。临床表现复杂,颅内高压为主要表现之一。CT、MRI增强扫描病灶多呈均匀明显强化,可单发或多发。35例患者中位生存时间23月,1年生存率74．3％,3年生存率25．7％,5年生存率5．71％。肿瘤全切及局部切除者,生存率未见明显统计学差异（P=0．053）,加化疗疗效优于不加化疗（P=0．012）。结论：PCNSL临床表现多样,影像学缺乏特异性,极易误诊,确诊需要依靠病理学检查,最佳治疗方案是手术加放疗、化疗的联合治疗。PCNSL侵袭性强,生存期短,其预后主要与发病年龄、多灶性、一般状态有关。     

原发性中枢神经系统淋巴瘤患者预后的影响因素分析

目的 探讨原发性中枢神经系统淋巴瘤(PCNSL)患者预后的影响因素.方法 收集82例PCNSL患者的临床资料,包括性别、年龄、病灶数量、病灶部位、病灶直径、治疗方法、意识状态、体力状况(PS)评分等一般资料,以及脑脊液(CSF)常规检测指标(CSF蛋白质、CSF氯化物)和生化检测指标[血清乳酸脱氢酶(LDH)、β2微球...     

原发性中枢神经系统淋巴瘤35例临床及预后分析

目的:探讨原发中枢神经系统淋巴瘤(PCNSL)临床特点、诊治方案及临床疗效。方法:总结2001年1月-2008年1月收治的35例PCNSL患者,均经病理证实为B细胞来源非霍奇金淋巴瘤并接受放疗,其中25例放疗后接受化疗。结合文献对原发性中枢神经系统淋巴瘤患者的临床特点、病理学检查、影像学表现、治疗及预后进行回顾性分析。结果:本病以中老年人多见,发病急,病程短,病情进展快。临床表现复杂,颅内高压为主要表现之一。CT、MRI增强扫描病灶多呈均匀明显强化,可单发或多发。35例患者中位生存时间23月,1年生存率74.3%,3年生存率25.7%,5年生存率5.71%。肿瘤全切及局部切除者,生存率未见明显统计学差异(P=0.053),加化疗疗效优于不加化疗(P=0.012)。结论:PCNSL临床表现多样,影像学缺乏特异性,极易误诊,确诊需要依靠病理学检查,最佳治疗方案是手术加放疗、化疗的联合治疗。PCNSL侵袭性强,生存期短,其预后主要与发病年龄、多灶性、一般状态有关。     

Temozolomide and methotrexate for primary central nervous system lymphoma in the elderly

Background Treatment for primary CNS lymphoma (PCNSL) in the elderly is associated with lower response rates and higher risks of acute and late delayed toxicity as compared to younger patients. Temozolomide has emerged as a new alternative treatment for PCNSL and constitutes an attractive option for the elderly because of its favorable toxicity profile. In this study we report outcomes of a consecutive series of PCNSL elderly patients initially treated with an innovative regimen combining methotrexate and temozolomide without radiotherapy or intra-thecal chemotherapy. Methods Histologically confirmed newly-diagnosed PCNSL patients older than 60 years were included. An induction chemotherapy was initially given (methotrexate 3 g /m² on days 1, 10, and 20, and temozolomide 100 mg/m² on days 1–5). Patients achieving a partial or complete response proceeded to a maintenance phase (up to 5 monthly cycles of methotrexate 3 g/m² on day 1, and temozolomide 100 mg/m² days 1–5). Non-responders were treated on an individual basis. Results Among the 23 included patients, a complete response was observed in 55%, and disease progressed in the other 45%. Median event-free survival was 8 months, and median overall survival was 35 months. Grades 3 or 4 toxicities included nephrotoxicity in three patients, and hematotoxicity in five; no neurotoxicity has been observed to date. One patient died while on treatment from complications of intestinal obstruction. Conclusion Our efficacy results are comparable to other reported regimens, with the advantages of a favorable toxicity profile, and absence of intra-thecal chemotherapy. Prospective, controlled studies are warranted to confirm such results.     

Association of transcobalamin c. 776C>G with overall survival in patients with primary central nervous system lymphoma

Background:

Chemotherapy for primary central nervous system lymphoma (PCNSL) is based on methotrexate (MTX), which interferes with both nucleic acid synthesis and methionine metabolism. We have reported previously that genetic variants with influence on methionine metabolism are associated with MTX side effects, that is, the occurrence of white matter lesions as a sign of MTX neurotoxicity. Here, we investigated whether such variants are associated with MTX efficacy in terms of overall survival in MTX-treated PCNSL patients.

Methods:

We analysed seven genetic variants influencing methionine metabolism in 68 PCNSL patients treated with systemic and facultative intraventricular MTX-based polychemotherapy (Bonn protocol).

Results:

Median age at diagnosis was 59 years (range: 28–77), 32 patients were female. Younger age (Wald=8.9; P=0.003) and the wild-type C (CC) allele of the genotype transcobalamin c (Tc2). 776C>G (Wald=6.7; P=0.010) were associated with longer overall survival in a multivariate COX regression analysis.

Conclusion:

This observation suggests that the missense variant Tc2. 776C>G influences both neurotoxicity and efficacy of MTX in the Bonn PCNSL protocol.