Retrospective Analysis of a Cohort of Patients with Metastatic Bladder Cancer with Metastatic Sites Limited to the Pelvis and Retroperitoneum Treated at a Single Institution between 2009 and 2020.

Bladder cancer (BC) presenting with pelvic and retroperitoneal lymph nodes presents a therapeutic challenge. The impact of chemoradiotherapy on pelvic and retroperitoneal lymph node metastasis as a consolidation treatment has not been established. Between 2009 and 2020, 502 patients who were treated with first-line chemotherapy for BC in our center, were retrospectively identified. Patients who received chemoradiotherapy or radiotherapy with an equivalent radiation dose superior to 30 Gy were included in the RTCT group, and other patients were included in the control group (CT group). We performed an analysis of progression-free survival (PFS) and overall survival (OS) for these two cohorts using the Kaplan-Meier method. A total of 89 patients were included, 24 in the RTCT group and 65 in the CT group. Chemoradiotherapy improved both OS ( = 0.034) and PFS ( = 0.009) in comparison with chemotherapy alone: 26.3 months (95% IC 0.0-52.9) and 19.4 months (95% IC 5.0-33.7), respectively, in the RTCT group versus 17.2 months (95% IC 13.7-20.6) and 11.2 months (95% IC 8.6-13.8), respectively, in the CT group. Grade 3/4 toxicity was related to chemotherapy and to chemoradiotherapy at levels of 31% and 24%, respectively. For mBC with metastatic regional or retroperitoneal lymph nodes, chemoradiotherapy seems to confer benefits for both OS and PFS.