Treatment for primary CNS lymphoma: The next step

Purpose: The use of preradiotherapy (WT) methotrexate (MTX) has improved di sease control and survival in patients with primary CNS lymphoma (PCNSL). T he reported protocol was designed to optimize and enhance the chemotherapeu tic component of treatment. Patients and Methods: fifty-two patients were treated with five cycles of h igh-dose MTX 3.5 g/m(2), procarbazine 100 mg/m(2)/d, and vincristine 1.4 mg /m(2). Thirty patients received whole-brain RT (45 Gy). Twenty-two older pa tients deferred RT to diminish the risk of delayed neurotoxicity; these pat ients are compared with 12 older patients who completed the entire treatmen t regimen. Most patients (n = 35) received high-dose cytarabine after RT. Results: Objective response rate to the induction chemotherapy regimen was 90%; overall median survival is 60 months. Grade 3 or 4 myelosuppression wa s seen in 30 patients, primarily in association with cytarabine; grade 3 ne phrotoxicity due to MTX was seen in two patients. Older patients had simila r median survival with or without the addition of RT: 32 versus 33 months, respectively. However, late neurotoxicity was significantly more common in those older patients who received RT (P = .00004). Patients younger than 60 years who received the complete treatment regimen have not reached median disease-free or overall survival. Conclusion: increasing the dose of MTX and adding procarbazine and vincrist ine improved disease control and overall survival in patients with newly di agnosed PCNSL. Younger patients in particular fared extremely well with thi s treatment regimen. In older patients, deferring whole-brain RT did not co mpromise overall survival but did reduce treatment-related toxicity. (C) 20 00 by American Society of Clinical Oncology.