Bowel surveillance patterns after a diagnosis of colorectal cancer in Medicare beneficiaries

Background: Postoperative colon surveillance has been recommended for patie nts with a diagnosis of local/regional colorectal cancer. The extent to whi ch these recommendations are followed in practice is poorly characterized. Patterns of surveillance after surgery for colorectal cancer were determine d by using a large population-based database. Methods: This is a retrospective cohort study with cancer registry data lin ked to Medicare claims. Identified were 52,283 patients treated for local/r egional colorectal cancer between 1986 and 1996, and surveillance patterns through 1998 were determined. Surveillance patterns were analyzed by using survival analysis and by computing the proportion of surviving patients who underwent procedures during 4 time periods after treatment: 2 to 14 months , 15 to 50 months, 51 to 86 months and more than 87 months. Results: Median times to first through fifth surveillance events were 20,14 ,15,15, and 15 months, respectively. For 17% of the cohort there was no sur veillance event. Younger patients were more likely to undergo surveillance. Surveillance patterns were not affected by stage. The proportions of the c ohort that underwent no surveillance during the 4 respective time periods w ere 54%, 52%, 60%, and 69%. The percentages of patients who underwent surve illance annually or more frequently in the latter 3 time periods, respectiv ely, were 19%, 10%, and 5%, or 11% overall, treating the data for the 3 eve nts as a whole. Over the period from 1986 to 1998, the proportion of patien ts who had no surveillance procedures gradually decreased, whereas the prop ortion of those who underwent procedures annually or more frequently remain ed relatively constant. Conclusions: During the period from 1986 to 1998 there was low utilization of postdiagnosis colon surveillance in a substantial proportion of elderly patients with a diagnosis of local/regional colorectal cancer. Over time th ere was a trend toward increasing receipt of any surveillance procedures. T he percentages of patients undergoing surveillance annually or more frequen tly did not change between earlier and later periods.