The primary outcome of interest was a diagnosis of first primary crc. Secondary outcomes were right-sided crc (occurring at and proximal to the hepatic flexure) and left-sided crc (occurring in the transverse and more distal colon).
We found that patients with a diagnosis of uca did not have a subsequently increased risk of crc. Those results agree with findings in some earlier studies 19,20, including one from our institution 21,
and contrast with the findings in a U.S. Surveillance, Epidemiology,
and End Results database study demonstrating an increase in crc incidence after a diagnosis of uca 22. None of the earlier studies used a competing risks analysis........... Increased risk of uca has been associated with Lynch syndrome14. Most evidence suggests that the increased risk is predominantly for uca of the upper urinary tract, including the renal pelvis and ureter 36. However, some studies indicate that, in Lynch syndrome, the risk of bladder cancer is increased as well 37,38. In the present study, we observed no increased risk of crc in all uca survivors or in patients with upper urinary tract tumours. There also did not appear to be an increased risk of right-sided crc. We did not find, in stratified analysis, an increased risk for those less than 60 years of age at time of uca diagnosis..........Given that the patients in the present study were relatively elderly
(median age 72 years), it is therefore likely that patients with Lynch
syndrome would have developed a first malignancy other than uca at an earlier age and would therefore have been excluded from the study