Prognostic impact of meningeal dissemination in primary CNS lymphoma (PCNSL): experience from the G-PCNSL-SG1 trial

Abstract

Background: We evaluated the frequency and prognostic impact of meningeal dissemination (MD) in immunocompetent adult patients with primary central nervous system lymphoma treated in a randomized phase III trial.

Patients and methods: MD was evaluated at study entry and defined by lymphoma proof in the meningeal compartment detected by at least one of the following methods: cerebrospinal fluid (CSF) cytomorphology, detection of clonal B cells by IgH PCR in CSF or contrast enhancement of the leptomeninges on magnetic resonance imaging (MRI).

Results: Data on MD were available in 415 patients, of those, MD was detected in 65 (15.7%): in 44/361 (12.2%) by CSF cytomorphology, in 16/152 (10.5%) by PCR and in 17/415 (4.1%) by MRI. Major patients' characteristics and therapy did not significantly differ between patients with MD (MD+) versus those without MD (MD-). There was a significant correlation of MD with CSF pleocytosis (>5/μl; P < 0.0001), but no correlation with CSF protein elevation (>45 mg/dl). Median progression-free survival was 6.7 months [95% confidence interval (CI) 0-14.5] in MD+ and 8.3 months (5.7-10.8) in MD- patients (P = 0.95); median overall survival was 21.5 months (95% CI 16.8-26.1) and 24.9 months (17.5-32.3), respectively (P = 0.98).

Conclusion: MD was detected infrequently and had no impact on outcome in this trial.