ALBERT

Description: Background: The outcome of DLBCL patients is improving, it however seems to be very poor for those who are refractory to the therapy. We have decided to analyze this group of patients. Methodology: As part of an observational clinical study NiHiL (GovTrial No NCT03199066) we identified the patients treated in the first line by R-CHOP like immunochemotherapy who met at least one criterium: 1. refractory (stable disease - SD or progression) on 1st line therapy (1st l- R), 2. refractory (SD or progression) on salvage (platinum based regimen) (Salv-R), 3. refractory to or relapse/progression within 12 months after ASCT (ASCT-R/R). There were 210 patients diagnosed in the period 2001-2017 who fulfilled the criteria. Progression-free survival (PSF) and overall survival (OS) were estimated from the time of determination of a refractory disease. Results: The cohort consisted of 163 patients primarily resistant to the first-line therapy, 31 patients were resistant to the salvage therapy and 16 patients progressed within 12 months after ASCT . At the time of the diagnosis, the median age was 65 years (22-91) (the same as at the refractory disease), 54% were males, 74% had advanced clinical stage (III+IV), 68% had IPI 〉3, 77% had above-normal LDH, and 45% had a tumor mass 〉10cm. The OS from the time of determination of refractory disease was 0.53 years, median PFS was 0.29 years. Patients under 65 years had median survival 0.8 years compared to 0.4 years in the group of patients above 65 years of age. The median PFS for 1st l-R, Salv-R and ASCT-R/R resp. was 0.3, 0.26 and 0.35 years resp. and 5y survival 22%, 0% and 6% resp. The median OS for 1st l-R, Salv-R and ASCT-R/R resp. was 0.55, 0.39 and 0.65 y resp. and 5y survival was 28%, 0% and 13% resp. Our results demonstrate that resistant DLBCL has an extremely poor prognosis, clearly new effective therapeutic strategies such as CAR-based therapies or others are required. This work was supported by a research program Progres Q28-9. Disclosures Belada: Seattle Genetics: Membership on an entity's Board of Directors or advisory committees, Research Funding; Roche: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Takeda: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen-Cilag: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Gilead Sciences: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding.