Combined treatment with high-dose methotrexate, vincristine and procarbazine, without intrathecal chemotherapy, followed by consolidation radiotherapy for primary central nervous system lymphoma in immunocompetent patients.

OBJECTIVES

To assess the feasibility and the activity, as well as the efficacy to treat meninges, of chemotherapy (CHT) containing high-dose methotrexate (HD-MTX) followed by radiation therapy (RT), without intrathecal CHT, in patients with primary central nervous system lymphoma.

METHODS

Eligibility criteria were histologically proven diagnosis, disease limited to the CNS, age < or = 70, ECOG performance status < or = 3, HIV-negative and no prior treatment. Thirteen patients (1996-1999; median age 54 years) received two courses of vincristine 1.4 mg/m2 day 1, MTX 3 g/m2 days 3 and 10 and procarbazine 100 mg/m2 days 1-14 every 4 weeks. Patients who achieved a complete remission were referred to RT, those with progressive disease were excluded from further study; all the remaining patients received a third course of CHT followed by RT.

RESULTS

Twelve patients responded to CHT (overall response rate = 92%, complete response rate = 77%): 9 underwent consolidation RT, 3 did not. Two patients experienced severe acute toxicity; lethal pulmonary thromboembolism and transient renal failure. Five patients relapsed: 2 after CHT and 3 after RT. Relapse was local in all cases, with a case of concomitant hepatic involvement. No cases of ocular or meningeal relapse were observed. In contrast to high-dose cytarabine-containing CHT, salvage therapy with temozolomide produced good results. Two patients died of treatment-related neurotoxicity. Six patients are alive with a median follow-up of 17 months, and a 2-year overall survival (OS) of 61%. The median survival of the 9 patients who completed the planned treatment is 25+ months with a 2-year OS of 80%.

CONCLUSIONS

HD-MTX, procarbazine and vincristine followed by RT, without intrathecal therapy, produce similar results with respect to other HD-MTX-containing regimens. These results seem to suggest that adequate meningeal treatment is possible without intrathecal drug delivery, even in CSF-positive patients. Corroborating data from a larger series are, however, necessary. Temozolomide should be tested in relapsed patients in a phase II prospective trial.