Clinical trials have shown that chemoradiotherapy (CRT) improves survival compared to radiation therapy (RT) alone in muscle-invasive bladder cancer. We describe uptake of CRT and comparative effectiveness in routine practice.
Electronic treatment records were linked to the population-based Ontario Cancer Registry to identify all patients with bladder cancer treated with curative-intent RT in 1999-2013. Modified Poisson regression was used to analyze factors associated with use of CRT. Cox model and propensity score analyses were used to explore factors associated with cancer-specific (CSS) and overall survival (OS).
1192 patients underwent RT during 1999-2013; median age was 79. Use of CRT increased over time: 36% (124/341) in 1999-2003, 38% (153/399) in 2004-2008, 48% (217/452) in 2009-2013 (p = 0.001). Drug details were available for 82% (402/493) of CRT cases; the most common regimens were single-agent Cisplatin (57%, 230/402), single-agent Carboplatin (31%, 125/402) and 5-FU/Mitomycin (4%, 17/402). Factors associated with CRT include younger age (p < 0.001), lower comorbidity (p = 0.001), and geographic region (range 14-89%, p < 0.001). Five year CSS and OS among CRT cases were 45% (95%CI 39-51%) and 35% (95%CI 30-40%). On adjusted analyses CRT was associated with superior survival compared to RT (CSS HR 0.70, 95%CI 0.59-0.84; OS HR 0.74, 95%CI 0.64-0.85); results were consistent on propensity score analysis. There was significant improvement in survival of all RT-treated cases (irrespective or chemotherapy delivery) in 2009-2013 compared to 1999-2003 (CSS HR 0.77, 95%CI 0.61-0.97; OS HR 0.82, 95%CI 0.69-0.98).
CRT is associated with superior survival compared to RT alone and its uptake corresponded to improved survival among all RT-treated cases in the general population. Uptake of CRT varies widely by geographic region.
Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology. 2018 Jan 03 [Epub ahead of print]
Ketan Ghate, Kelly Brennan, Safiya Karim, D Robert Siemens, William J Mackillop, Christopher M Booth
Department of Oncology, Queen's University, Kingston, Canada., Division of Cancer Care and Epidemiology, Queen's University Cancer Research Institute, Kingston, Canada., Department of Oncology, Queen's University, Kingston, Canada; Division of Cancer Care and Epidemiology, Queen's University Cancer Research Institute, Kingston, Canada., Department of Oncology, Queen's University, Kingston, Canada; Department of Urology, Queen's University, Kingston, Canada., Department of Oncology, Queen's University, Kingston, Canada; Division of Cancer Care and Epidemiology, Queen's University Cancer Research Institute, Kingston, Canada. Electronic address: .