Characteristics and outcome of patients with primary CNS lymphoma in a "real-life" setting compared to a clinical trial.

We aimed to compare the characteristics and outcome of patients treated within the multi-centre German Primary CNS Lymphoma Study Group 1 trial (G-PCNSL-SG-1; TRIAL group) and patients treated outside this clinical trial ("real-life" setting, R-LIFE group). Therefore, we conducted a retrospective single-centre study in order to analyse all patients with newly diagnosed primary CNS lymphoma (PCNSL) treated consecutively in our institution between November 2000 and June 2015. Altogether, 86 patients were analysed (median 68 years). Twenty patients were treated within (TRIAL) and 66 patients outside the clinical trial (R-LIFE), respectively. The majority (n = 75; 87 %) received high-dose methotrexate as the first-line treatment. Thirty-eight of 66 patients (57.6 %) responded to the first-line therapy. The R-LIFE patients were older (median age 70 vs. 62 years; p = 0.005) and had more frequently a worse performance status (ECOG score 2-4: 59.1 vs. 20.0 %; p = 0.004; median Karnofsky index 70 vs. 80 %; p = 0.003) and less frequently a low prognostic score (IELSG score 0-1: 19.7 vs. 45.0 %; p = 0.038), than the TRIAL patients. Median overall survial (OS) was shorter for the R-LIFE patients (9.3 months [95 % CI 1.9-16.7] vs. 33.4 months [95 % CI 17.6-49.2]; p = 0.065). Median progression-free survival (PFS) was significantly inferior for the R-LIFE patients (3.4 months [95 % CI 2.4-4.4] vs. 24.8 months [95 % CI 4.6-45.0]; p = 0.037). Our data indicate that the outcome of PCNSL patients treated outside, but about analogous to the G-PCNSL-SG-1 trial, was poor. This is likely explained by more unfavourable prognostic factors in patients being treated off trial.