Thiel, Eckhard

Abstract Low-grade primary central nervous system lymphoma is a very rare subtype of primary central nervous system lymphoma (PCNSL), for which almost no data is currently available. The purpose of this retrospective study was to characterize the clinical presentation, course and outcome of patients with low-grade PCNSL. Forty patients (18 male, 22 female) from 18 cancer centers in five countries were identified with a median age of 58 (range, 19–78) years and a median Eastern Cooperative Oncology Group (ECOG) performance status of 1 (range, 0–4). The mean time to diagnosis was 14.8 months (range, 0.25–84). Thirty-two patients (80%) had a B-cell and eight a T-cell lymphoma. Thirty-seven patients (92.5%) showed involvement of a cerebral hemisphere or deeper brain structures, while two evidenced only leptomeningeal involvement, and one patient had spinal cord disease. Treatment was performed in 39 patients: chemotherapy and radiotherapy in 15 (38%), radiotherapy alone in 12 (30%), chemotherapy alone in 10 (25%), and tumor resection alone in two. The median progression-free survival (PFS), disease-specific survival (DSS) and overall survival (OAS) were 61.5 (range, 0–204), 130 (range, 1–204), and 79 (range, 1–204) months, respectively. An age ≥60 years was associated with a shorter PFS (P = .009), DSS (P = .015) and OAS (P = .001) in multivariate analysis. Low-grade PCNSL differ from the high-grade subtype in pathological, clinical and radiological features. In this study, the long-term outcome was better as compared to the results obtained in PCNSL in general with age ≥60 years adversely affecting survival.

Purpose To describe the demographic and tumor related characteristics and outcomes for patients with primary T-cell CNS lymphoma (TPCNSL). Patients and Methods A retrospective series of patients with TPCNSL was compiled from twelve cancer centers in seven countries. Results We identified 45 patients with a median age of 60 years (range, 3 to 84 years). Twenty (44%) had Eastern Cooperative Oncology Group (ECOG) performance status (PS) of 0 or 1. Twenty-six (58%) had involvement of a cerebral hemisphere and sixteen (36%) had lesions of deeper sites in the brain. Serum lactate dehydrogenase was elevated in 7 (32%) of 22 patients, and CSF protein was elevated in 19 of 24 patients (79%) with available data. The median disease-specific survival (DSS) was 25 months (95% CI, 11 to 38 months). The 2- and 5-year DSS were 51% (95% CI, 35% to 66%) and 17% (95% CI, 6% to 34%), respectively. Univariate and multivariate analyses were conducted for age (≤ 60 v > 60 years), PS (0 or 1 v 2, 3, or 4), involvement of deep structures of the CNS (no v yes), and methotrexate (MTX) use in the primary treatment (yes v no). Only PS and MTX use were significantly associated with better outcome with hazard ratios of 0.2 (95% CI, 0.1 to 0.4) and 0.4 (95% CI, 0.2 to 0.8), respectively. Conclusion This is the largest series ever assembled of TPCNSL. The presentation and outcome appear similar to that of B cell PCNSL. PS 0 or 1 and administration of MTX are associated with better survival.