Repeat biopsy in relapsed or refractory diffuse large B cell lymphoma: a nationwide survey and retrospective study.

Almost half of patients with diffuse large B-cell lymphoma (DLBCL) have relapsed/refractory (R/R) disease after frontline immunochemotherapy. Although guidelines recommend histological confirmation of R/R disease, repeat biopsies are not always performed. We conducted a two-part study: a nationwide case-vignette survey among treating hematologists, and a single center retrospective analysis. In the survey part, all 64 participating physicians opted not to perform a repeat biopsy in at least one scenario, more often in refractory cases. In the retrospective part, 116 episodes of R/R aNHL among 61 patients were identified. Repeat biopsy was not performed in 72%, more often in refractory episodes, mostly due to low likelihood of alternative diagnoses or problematic location for biopsy. Our study suggests that many patients do not undergo repeat biopsy in R/R DLBCL, especially in refractory cases. Future studies and recommendations should address the necessity of repeat biopsy, according to patient and disease related characteristics.