Risk of colorectal cancer after diagnosis of prostate cancer: A population-based study.

Abstract

3606 Background: Prior studies on risk of colorectal cancer (CRC) among survivors of prostate cancer (PC) have not controlled for important confounding factors such as competing risk of death and other cancers, and comorbidities. We assessed the risk of CRC (overall, sub-site- and treatment-specific) among PC survivors. Methods: A historical cohort study was performed by linking the Manitoba Cancer Registry and the Manitoba Health administrative databases. Each subject diagnosed with PC as his first cancer between 1987 and 2009 was age-matched with up to five men with no history of invasive cancer on the index date (date of PC diagnosis). All subjects were followed up to the date of diagnosis of CRC or another cancer, death, migration from the province, or study end-point (December 31, 2009). Competing-risk proportional hazard models were used to compare the CRC incidence rates with adjustment for age, history of lower gastrointestinal endoscopy, intensity of health care visits, diabetes and socio-economi...