Marco Foppoli

PURPOSE: Treatment of secondary CNS dissemination in patients with aggressive lymphomas remains an important, unmet clinical need. Herein, we report the final results of a multicenter phase II trial addressing a new treatment for secondary CNS lymphoma based on encouraging experiences with high doses of antimetabolites in primary CNS lymphoma and with rituximab plus high-dose sequential chemoimmunotherapy (R-HDS) in relapsed aggressive lymphoma. PATIENTS AND METHODS: HIV-negative patients with aggressive B-cell lymphoma and secondary CNS involvement at diagnosis or relapse, age 18 to 70 years, and Eastern Cooperative Oncology Group performance status ≤ 3 were enrolled and treated with high-doses of methotrexate and cytarabine, followed by R-HDS (cyclophosphamide, cytarabine, and etoposide) supported by autologous stem-cell transplantation (ASCT). Treatment included eight doses of rituximab and four doses of intrathecal liposomal cytarabine. The primary end point was 2-year event-free survival; the planned accrual was 38 patients. RESULTS: Thirty-eight patients were enrolled; CNS disease was detected at presentation in 16 patients. Toxicity was usually hematologic and manageable, with grade 4 febrile neutropenia in 3% of delivered courses and grade 4 nonhematologic toxicity in 2% of delivered courses. Four patients died because of toxicity. Autologous stem cells were successfully collected in 24 (89%) of 27 patients (median, 10 × 10(6)/kg); 20 patients underwent ASCT. Complete response was achieved in 24 patients (complete response rate, 63%; 95% CI, 48% to 78%). At a median follow-up of 48 months, 17 patients remained relapse free, with a 2-year event-free survival rate of 50% ± 8%. At 5 years, 16 patients were alive, with a 5-year overall survival rate of 41% ± 8% for the whole series and 68% ± 11% for patients who received transplantation. Systemic (extra-CNS) and/or meningeal disease did not affect outcome. CONCLUSION: The combination of high doses of antimetabolites, R-HDS, and ASCT is feasible and effective in patients age 18 to 70 years old with secondary CNS lymphoma, and we propose it as a new standard therapeutic option.

The most effective strategy to prevent central nervous system (CNS) dissemination in diffuse large B-cell lymphoma (DLBCL) remains an important, unmet clinical need. Herein, we report a retrospective analysis of risk-tailored CNS prophylaxis in 200 human immunodeficiency virus-negative adults with DLBCL treated with rituximab-CHOP (cyclophosphamide, doxorubicin, vincristine, prednisone) or similar. High risk of CNS relapse was defined by involvement of specific extranodal organs, or simultaneous presence of advanced stage and high serum lactate dehydrogenase level; CNS prophylaxis with high-dose methotrexate ± intrathecal chemotherapy (IT) was routinely used in high-risk patients diagnosed after 2007. CNS relapse risk was low in 93 patients and high in 107; 40 high-risk patients received prophylaxis, which consisted of IT alone in 7. At a median follow-up of 60 months, one low-risk and nine high-risk patients (1% vs. 8%; P = 0·01) experienced CNS relapse. In the high-risk group, CNS relapses occurred in 8/67 (12%) patients who did not receive prophylaxis and in 1/40 (2·5%) patients who did; the latter occurred in a patient managed with IT alone. CNS relapse rate was 12% (9/74) for patients treated with "inadequate" prophylaxis (none or IT only) and 0% (0/33) for patients managed with intravenous prophylaxis (P = 0·03). In conclusion, high-dose methotrexate-based prophylaxis significantly reduces CNS failures in high-risk patients stratified by involvement of specific extranodal sites and International Prognostic Index.

The authors assessed MATILDE chemotherapy followed by response-tailored radiation therapy in 41 patients aged 70 years or younger with primary CNS lymphoma in a Phase II trial. With response rates of 76% after MATILDE and 83% after chemotherapy with or without radiation therapy, this was an active strategy, particularly in low- to intermediate-risk patients (International Extranodal Lymphoma Study Group [IELSG] score). Myelosuppression was the dose-limiting toxicity, with 9.5% of lethal complications. After a median follow-up of 49 months, a plateau in the survival curve (5-year overall survival: 41 +/- 7%) was obtained.