For this study, the authors identified patients receiving initial chemotherapy for metastatic bladder cancer treatment during an index period from January 2010-June 2014 by review of electronic health records, with follow-up through July 2016. Patients who subsequently received second-line therapy were included in this analysis and the Kaplan-Meier method was utilized to evaluate outcomes from second-line treatment initiation.
Among the 1,155 patients receiving first-line treatment during the index period, 391 (33.9%) patients received second-line treatment and were eligible for analysis. The median age was 70 years (range 36-89) and 81.1% were men. Median time to initiation of second-line therapy following metastatic bladder cancer diagnosis was 7.8 months. Second-line therapy was used in 33.6% of patients who received first-line cisplatin-based therapies and 34.0% of those who received other first-line therapies. Of these second-line treated patients, 51.4% received combo-therapy, most commonly carboplatin/gemcitabine (14.8%), carboplatin/paclitaxel (12.0%), and cisplatin/gemcitabine (7.7%). Among second-line treated patients, 48.6% received monotherapy, most commonly paclitaxel (17.4%), docetaxel (10.5%), pemetrexed (8.2%), and gemcitabine (6.6%). For the composite outcome of third-line therapy initiation or death, the median time-to-event for all second-line regimens was 5.2 months (95%CI 4.5-6.0). Median overall survival (OS) for all second-line treatment regimens was 9.4 months (95%CI, 8.2-11.1). Time-to-event outcomes were significantly different across the various regimens (p = 0.0005).
In summary, this real-world data provides important insights into patterns of care and outcomes for second-line metastatic bladder cancer patients. These results concur with other observational studies in this time frame, suggesting that only one third of first-line metastatic bladder cancer patients progress to second-line treatment. Taxane and platinum-based regimens predominated in the second-line, although patterns of treatment were consistent with prior research showing that no clear standard of care exists for these patients. Monotherapy and combination regimens are utilized in equal proportions, both producing poor outcomes for metastatic bladder cancer patients.
Speaker: Kyle Flannery, Kenilworth, United States of America
Co-Authors: J. Black-Shinn (The Woodlands, United States of America) M. Boyd (The Woodlands, United States of America) N. Robert (The Woodlands, United States of America) A. Kamat (Houston, United States of America)
Written By: Zachary Klaassen, MD, Urologic Oncology Fellow, University of Toronto, Princess Margaret Cancer Centre, Twitter: @zklaassen_md at the European Society for Medical Oncology Annual Congress - September 8 - 12, 2017 - Madrid, Spain