Primary central nervous system lymphoma in Japan: A nationwide survey

Purpose: To analyze clinical features, treatment results, and prognostic fa ctors of primary central nervous system lymphoma (PCNSL) in Japan, we condu cted a nationwide survey. Methods and Materials: We analyzed 466 patients with histologically proven PCNSL treated between 1985 and 1994 at 62 institutions, including 56 medica l schools. Results: Patient and tumor characteristics of the 366 patients were not gre atly different from those reported previously, except for the relatively hi gh proportion of T-cell lymphoma (8.5%). The median survival time of the 46 6 patients was 18 months, and the 5- and 10-year survival rates were 15.2% and 8.2%, respectively. Complete response was observed in 63% of evaluable patients, but 64% of the complete responders developed recurrence (77% with in the irradiated volume). Among patient- or tumor-related factors, higher age, worse performance status, presence of B symptom, multiple lesions, pre sence of meningeal dissemination, and elevated lactate dehydrogenase (LDH) level were associated with poorer survival, whereas no significant differen ce was observed in prognosis with respect to sex, T/B phenotype, or histolo gical subclassification, In 410 patients receiving at least 40 Gy to the tu mor, there was no difference in survival with respect to total radiation do se or field. Patients receiving 2 or more cycles of systemic chemotherapy h ad a slightly longer median survival time (22 months) acid higher 5-year su rvival rate (20%) than those receiving radiotherapy alone (18 months and 17 %, respectively), but the difference was not significant (p = 0.13), No che motherapy protocol appeared to be better than any other. Conclusions: In addition to age and performance status, which are well-know n prognostic factors, B symptom, tumor number, presence of meningeal dissem ination, and serum LDH level also seemed to influence survival. Higher radi ation dose was not associated with better prognosis. The role of chemothera py could not be clarified because of the use of various protocols, but it s eemed that the influence of various prognostic factors is greater than the effect of chemotherapy. (C) 1999 Elsevier Science Inc.