Objective: To clarify the efficacy of chemotherapy after radiation therapy in immunocompetent patients with primary central nervous system lymphoma (PCNSL).
Patients and methods: A retrospective analysis of 22 PCNSL patients was performed. Twenty-two patients were divided into a combined treatment (chemotherapy after radiation) group and a radiation group. The survival curves, calculated according to the Kaplan and Meier method, were compared using the Log-rank and Wilcoxon statistical analyses.
Results: Eight patients were treated with radiation therapy alone, and their median survival time (MST) after diagnosis was 21.9 months. Fourteen patients were treated with chemotherapy after radiotherapy. Six patients received chemotherapy consisting of cyclophosphamide, adriamycin, vincristine and prednisolone (CHOP), while 6 patients received carboplatin-based chemotherapy and 2 patients received methotrexate-based chemotherapy. The MST of these 14 patients was 34.4 months, which was not significantly better than that of the radiation therapy group (p=0.159). Leukoencephalopathy occurred in 3 patients, who received whole brain radiation.
Conclusion: The use of chemotherapy after radiation has up to now been thought to be a standard treatment modality but CHOP or carboplatin-based chemotherapy did not improve the survival time.