Patients with Primary Central Nervous System Lymphoma Not Eligible for Clinical Trials: Prognostic Factors, Treatment and Outcome

Patients with primary central nervous system lymphoma (PCNSL) not fulfilling inclusion criteria for clinical trials represent an underreported population. Thirty-four consecutive PCNSL patients seen at our center between 2005 and 2019 exclusion therapeutic were analyzed (non-study patients) compared from the G-PCNSL-SG-1 (German Study Group 1) study (study patients), largest prospective multicenter trial on PCNSL, comprising 551 patients. Median follow up was 68 months (range 1–141) in non-study 51 (1–105) Twenty-seven/34 (79.4%) received high dose methotrexate (HDMTX), while seven/34 (20.6%) a glomerular filtration rate (GFR) < 50 mL/min did not. overall survival (OS) six (95% confidence interval [CI] 0–21 months) those 34 The 27 treated HDMTX 526/551 who had as well. OS 20 CI 0–45)/21 18–25) non-study/526 (p = 0.766). Favorable prognostic factors young age, application of early response magnet resonance imaging (MRI). If HDMTX-based chemotherapy can be applied, long-term disease control is possible even qualifying trials. Initial MRI might useful decision treatment continuation.