Prevalence of any size adenomas and advanced adenomas in 40- to 49-year-old individuals undergoing screening colonoscopy because of a family history of colorectal carcinoma in a first-degree relative.

BACKGROUND

Per current guidelines, patients with a first-degree relative (FDR) with colorectal cancer (CRC) should get screened at least at age 40. Data about the prevalence of adenomas and advanced adenomas (AAs) in these patients are lacking.

OBJECTIVE

To examine the prevalence of adenomas and AAs in 40- to 49-year-old individuals undergoing screening colonoscopy for family history of CRC.

DESIGN

Retrospective chart review.

PATIENTS

Asymptomatic patients 40 to 49 years of age undergoing their first screening colonoscopy at the University of Michigan during the period 1999 to 2009 because of an FDR with CRC.

MAIN OUTCOME MEASUREMENTS

Prevalence of adenomas (any size), AAs, and risk factors associated with adenomas.

RESULTS

Among 640 study patients, the prevalence of adenomas (any size) was 15.4% and 3.3% for AAs. Adenoma prevalence was lower if the FDR with CRC was younger than 60 years of age versus an FDR with CRC older than 60 years of age (12.4% vs 19%, P = .034). Male sex (odds ratio 2.6; 95% CI, 1.06-4.4) and advancing age (odds ratio 1.16; 95% CI, 1.03-1.31) were associated with adenomas.

LIMITATIONS

Limited data on risk factor exposure and insufficient sample size to assess risk factors for AAs.

CONCLUSIONS

Among 40- to 49-year-old patients undergoing screening colonoscopy because of an FDR with CRC, the prevalence of adenomas and AAs is low. Further research should determine whether these individuals have a higher prevalence of adenomas compared with average-risk individuals.