A nonradiation-containing, intermediate-dose methotrexate regimen for elderly patients with primary central nervous system lymphoma

To assess the efficacy, acute toxicity, and delayed neurotoxicity of intermediate-dose methotrexate (MTX)-containing chemotherapy without whole-brain radiotherapy in the treatment of elderly patients with primary central nervous system lymphoma (PCNSL), we conducted a retrospective analysis of elderly patients (N = 17; median age 67) with newly diagnosed PCNSL who were treated with chemotherapy alone at Tsukuba University Hospital from January 2005 to December 2009. Induction therapy consisted of intravenous intermediate-dose MTX (1 g/m²), ranimustine, procarbazine, methylprednisolone, and intrathecal MTX and cytarabine. Patients who achieved complete response (CR) or partial response (PR) received 5 cycles of maintenance therapy every 6 weeks. All patients in this study achieved CR or PR and received maintenance therapy. Overall survival (OS) and progression-free survival (PFS) were 100 and 80% at 1 year, and 61 and 43% at 2 years, respectively. The median OS and PFS were 36 and 20 months, respectively. Delayed neurotoxicity did not develop in any patient before lymphoma progression. In terms of response rate, OS, and PFS, the nonradiation-containing, intermediate-dose MTX-containing protocol used in elderly Japanese patients was comparable to previous protocols that consisted of more intensive chemotherapy. Acute and delayed toxicities were manageable and quality of life was maintained until progression.