The mean number of adenomas per patient for each year of follow-up was 0.66 (IQR, 0-4.08; range, 0-4.34) with MSH2/EPCAM carriers having the greatest average number of adenomas per year relative to other carriers (IQR, 0-4.08; range, 0-4.08; P<0.001). This evidence concerns the gene MSH2 and adenoma.