Division of Cancer Care & Epidemiology, Cancer Research Institute, Queen's University, Kingston, ON, Canada
Christopher M. Booth , D. Robert Siemens , Yingwei Peng , Ian Tannock , William J. Mackillop
Background: Few studies have documented regimens used and timing of peri-operative chemotherapy for MIBC in routine practice. In metastatic bladder cancer cisplatin has superior efficacy to carboplatin. Time to initiation of adjuvant chemotherapy (TTAC) from surgery is known to be associated with survival in other solid tumors. Here we describe regimens used and TTAC in the general population of Ontario, Canada. Methods: Treatment and physician billing records were linked to the Ontario Cancer Registry to describe use of neoadjuvant (NACT) and adjuvant (ACT) chemotherapy among all patients with MIBC treated with cystectomy in Ontario 1994-2008. Time to initiation of ACT (TTAC) was measured from cystectomy. Multivariate Cox regression was used to identify factors associated with overall (OS) and cancer-specific survival (CSS). Results: Of 2944 patients undergoing cystectomy, 4% (129/2944) and 19% (571/2944) were treated with NACT and ACT respectively. Five-year OS was 25% (95%CI 17-34%) for NACT, 29% (95%CI 25-33%) for ACT cases. Among patients with identifiable drug regimens, cisplatin was used in 82% (253/308) and carboplatin in 14% (43/308). The most common regimens were gemcitabine-cisplatin (54%, 166/308) and MVAC (21%, 66/308). Mean TTAC was 10 weeks; 23% of patients had TTAC >12 weeks. Advanced age (70+ years OR 3.86, 95%CI 1.25-11.9) and lower socioeconomic status (poorest quintile OR 2.38, 95%CI 1.13-5.02) were more likely to have TTAC > 12 weeks. Patients with node positive disease were less likely to have TTAC >12 compared to node negative (OR 0.58, 95%CI 0.34-0.99). TTAC greater than 12 weeks was associated with inferior OS (HR 1.28, 95%CI 1.00-1.62) and CSS (HR 1.30, 95%CI 1.00-1.69). In adjusted analyses, OS and CSS were lower among patients treated with carboplatin compared to those treated with cisplatin; OS HR 2.14 (95%CI 1.40-3.29) and CSS HR 2.06 (95% CI 1.26-3.37). Conclusions: Most patients with MIBC in the general population receive cisplatin and this may be associated with superior outcomes to carboplatin. Initiation of ACT beyond 12 weeks is associated with inferior survival. Patients should start ACT as soon as they are medically fit to do so.
Disclaimer
This material on this page is ©2024 American Society of Clinical Oncology, all rights reserved. Licensing available upon request. For more information, please contact licensing@asco.org
Abstract Disclosures
2024 ASCO Genitourinary Cancers Symposium
First Author: Yu Zeng
2024 ASCO Genitourinary Cancers Symposium
First Author: Chiara Mercinelli
2022 ASCO Annual Meeting
First Author: Elizabeth R. Plimack
2023 ASCO Genitourinary Cancers Symposium
First Author: Matt D. Galsky