Abstract
INTRODUCTION: MALT (mucosae associated lymphoid tissue) lymphomas represent a low grade, rare and poorly known subtype (approximately 5%) of central nervous system (CNS) lymphoma. Their management is not standardized and their long-term prognosis remains unknown. The main objective of this study is to better define the clinical and radiological patterns of these tumors as well as their evolution and prognosis after treatment. METHODS: The cases of MALT CNS lymphomas treated since 2000 in our institution have been identified through the neuro-oncology department database. All biological, clinical and radiological data were collected retrospectively from medical records. RESULTS: Ten out of 422 CNS lymphomas listed were diagnosed as MALT lymphomas. Four of them were primary CNS lymphomas while 6 were associated with systemic involvement. Median age at diagnosis was 57,9 years (48,4-77,8) and sex ratio (F/M) was 9:1. Seven out of 10 patients showed dural location, 2/10 both dural and parenchymatous location and 1/10 exclusive parenchymatous location. Four out of 10 cases were located/unique forms while 6/10 were diffuse/multiple forms. Only 2/10 cases had a lymphomatous meningitis. Five out of 10 patients received chemotherapy (CT) alone, 4/10 surgery and chemotherapy and 1/10 chemotherapy and radiotherapy (RT). Chemotherapy consisted in rituximab-fludarabine-based CT in 4/10 cases, R-CHOP-based CT in 2/10 cases and high-dose methotrexate-based CT in 4/10 cases. Median duration of follow-up was 49 months, without neurotoxicity reported. Six out of 10 patients achieved complete response (CR) after initial therapy, 3/10 achieved partial response (PR) and 1/10 was stable. Median progression free survival was 43 months (95% CI, 17-68) and 4 years overall survival was 86%. DISCUSSION AND CONCLUSION: We report the largest chemotherapy-treated cohort of MALT CNS lymphomas. As previously described, most of them had dural location and looked like meningioma, but they were more often diffuse/multiple forms (only 1/3 of the cases in the literature). All our cases received CT while the great majority of the 79 MALT CNS lymphomas reported in the literature underwent surgery and/or RT with about 70% of CR. Adjuvant CT was associated in only about 1/3 of the cases. Response duration and long-term neurotoxicity were rarely reported because of a short follow-up period (≤3 years in about 2/3 of the cases). In our series, similar results were obtained with CT on disease control without neurotoxicity reported. Accordingly, chemotherapy should be discussed in multidisciplinary national meeting as a valid treatment option for MALT CNS lymphoma.