To characterize the presentation, patterns of care, and outcomes of radiation-associated muscle-invasive bladder cancer (RA-MIBC) compared to primary (non-radiation associated) MIBC. RA-MIBC has been suggested to represent a more aggressive disease variant and be more difficult to treat compared to primary (non-radiation associated) MIBC.
We identified 60,090 patients diagnosed with MIBC between 1988-2015 using the Surveillance, Epidemiology, and End Results database and stratified patients based on whether radiation had been administered to a prior pelvic primary cancer. We used Fine-Gray competing risks regression to compare adjusted bladder cancer-specific mortality (BCSM) for RA-MIBC compared to primary MIBC.
There were 1,093 patients with RA-MIBC and 58,997 patients with primary MIBC. RA-MIBCs were more likely to be T4 at diagnosis (21.0% vs 17.3%, p<0.001), and less likely to be node-positive (10.3% vs 17.1%, p<0.001). The rate of 5-year BCSM was significantly higher for patients with RA-MIBC vs. primary MIBC (56.1% vs 35.3%, AHR 1.24, p<0.001), even after stratification by other tumor, treatment and patient-specific factors.
RA-MIBCs tended to present with higher grade and T stage disease and were less likely to receive curative treatment. Even when accounting for stage, grade, and receipt of treatment, patients with RA-MIBC had worse survival compared to those with primary MIBC. These findings suggest that RA-MIBC present unique clinical challenges and may also represent a biologically more aggressive disease compared to primary MIBC. Future research is needed to better understand the biology of RA-MIBC and develop improved treatment approaches.
Urology. 2021 Apr 12 [Epub ahead of print]
Sybil T Sha, Edward Christopher Dee, Matthew Mossanen, Brandon A Mahal, Cierra Zaslowe-Dude, Trevor J Royce, Michelle S Hirsch, Guru Sonpavde, Mark A Preston, Paul L Nguyen, Kent W Mouw, Vinayak Muralidhar
Geisel School of Medicine at Dartmouth, Hanover, NH, USA; Department of Radiation Oncology, Dana-Farber Cancer Institute/Brigham and Women's Hospital, Harvard Medical School, Boston, MA USA. Electronic address: ., Department of Radiation Oncology, Dana-Farber Cancer Institute/Brigham and Women's Hospital, Harvard Medical School, Boston, MA USA., Department of Surgery, Division of Urology, Dana-Farber Cancer Institute/Brigham and Women's Hospital, Harvard Medical School, Boston, MA USA., Department of Radiation Oncology, University of Miami Miller School of Medicine, Miami, FL USA., Department of Pathology, Brigham and Women's Hospital, Boston, MA, USA., Department of Medicine, Section of Medical Oncology, Baylor College of Medicine, Houston, Texas, USA., Department of Urology, Dana-Farber Cancer Institute/Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
PubMed http://www.ncbi.nlm.nih.gov/pubmed/33857569