Background: High-dose methotrexate (MTX) and whole brain radiation therapy (WBRT) prolong survival in primary CNS lymphoma (PCNSL) patients but have been associated with delayed neurotoxicity. Consequently, patients are often treated with chemotherapy alone, and WBRT is deferred until relapse.
Methods: We performed a retrospective study to evaluate the safety and efficacy of salvage WBRT. Radiographic response, survival, and late neurotoxicity were assessed as the main endpoints.
Results: Forty-eight patients received salvage WBRT for PCNSL progression or recurrence. After WBRT, 58% achieved a complete radiographic response, 21% achieved a partial response, 6% had stable disease, and 15% progressed. The median survival from initiation of WBRT was 16 months, and 54% were alive 1 year after WBRT. The median time to PCNSL progression was 10 months; 15 patients (31%) had no subsequent disease recurrence after WBRT. Age younger than 60 years and complete response to WBRT were associated with better outcome. Treatment-related neurotoxicity was observed in 22% of patients. Patients older than 60 years and those treated less than 6 months from MTX therapy were at increased risk for development of neurotoxicity.
Conclusions: Salvage whole brain radiation therapy (WBRT) is effective for recurrent and refractory primary CNS lymphoma. Reserving WBRT until tumor recurrence is a reasonable strategy to minimize or delay the risk of treatment-related neurotoxicity.