Primary central nervous system lymphoma: treatment with chemotherapy and radiotherapy.

Between 1989 and 1993, 22 HIV negative patients with primary central nervous system lymphoma (PCNLS) were treated with three different regimens. In group A, 13 patients received preradiotherapy systemic and intrathecal methotrexate (MTX), radiotherapy (RT) and three courses of post-RT chemotherapy (CT) with thiotepa and procarbazine. In group B, 4 patients received a similar CT only after RT and without intrathecal MTX in 3/4 cases. In group C, 5 elderly patients received CT alone. In group A, 9/13 patients achieved response after pre-RT CT and 12/13 were in complete response (CR) after RT. After a median follow-up of 27 months, 8/13 (62%) patients are alive but 4 have leucoencephalopathy and cognitive dysfunction. In group B, all 4 patients were in CR after RT but the 3 patients who did not receive intrathecal MTX died within 10 months with meningeal recurrence. In group C, 4/5 patients had a response to CT. 2 patients died of recurrent tumour at 5 and 10 months, and 2 are living in CR 11+ and 21+ months after diagnosis, 1 after salvage CT. Combined treatment with RT and CT is useful in PCNSL but adequate treatment of the meninges is required. CT alone is sometimes of value in elderly patients in whom RT is not indicated.