Real Life Clinical Outcomes of Relapsed/refractory Diffuse Large B Cell Lymphoma in the Rituximab Era: the STRIDER Study

Background: Relapse and refractory (R/R) rates after first-line R-CHOP in diffuse large B cell lymphomas (DLBCL) are similar to 40% and similar to 15% respectively. Aims: We conducted a retrospective real-world analysis aimed at evaluating clinical outcomes of R/R DLBCL patients. Material and Methods: Overall, 403 consecutive DLBCL patients treated in two large hematological centers in Torino, Italy were reviewed. Results: At a median follow up of 50 months, 5-year overall survival from diagnosis (OS-1) was 66.5%, and 2-year progression free survival (PFS-1) was 68%. 134 (34.4%) patients relapsed (n = 46, 11.8%) or were refractory (n = 88, 22.6%) to R-CHOP. Most employed salvage treatments included platinum salt-based regimens in 38/134 (28.4%), lenalidomide in 14 (10.4%). Median OS and PFS after disease relapse or progression (OS-2 and PFS-2) were 6.7 and 5.1 months respectively. No significant difference in overall response rate, OS-2 or PFS-2 in patients treated with platinum-based regimens versus other regimens was observed. By multivariate analysis, age between 60 and 80 years, germinal center B cell type cell of origin and extranodal involvement of <2 sites were associated with better OS-2. Discussion: Our findings confirm very poor outcomes of R/R DLBCL in the rituximab era. Widespread approval by national Medicine Agencies of novel treatments such as CAR-T cells and bispecific antibodies as second-line is eagerly awaited to improve these outcomes.