What is the consequence of hyperplastic polyps? Do adenomas and colorectal cancer develop in these patients? A clinical study.

Aim: Do patients with hyperplastic polyps (HP) have an increased risk for developing adenomas and colorectal cancer (CRC)? A study was done to detect the number of patients developing adenomas and CRC.

Material And Methods: From 1990-1995 all patients with a HP diagnosed via endoscopy and significant follow-up were studied. The patients were separated in three groups; Group 1 HP in patients with previous adenoma and/or CRC. Group 2 HP with a concurrent adenoma and/or CRC. Group 3 patients with only HP.

Results: Group 1 consisted of 20 patients, group 2 of 39 patients, and group 3 of 136 patients The follow-up was 12.5, 12.6, and 13.4 years respectively. In group 1 there was one patient with an adenoma in the index investigation.In group 2 adenomas were seen coinciding to hyperplastic polyp(s) in 29 patients, while in 11 cases there was a colorectal cancer. Obviously patients in group 3 only had hyperplastic polyps. In group 1 7 patients previously had an adenoma and 12 previously had colorectal cancer. Four patients in group 3 developed cancer : 13, 14, 15, and 15 years after the detection of a hyperplastic polyp. In group 2 only one patient developed cancer in the cecum 9 years after the index investigation. In the four patients of group 3 who developed cancer no one previously had a serrated adenoma at revision of the original histology. Twelve patients developed an adenoma.

Conclusion: Only five CRC's developed in patients with HP. Thus, at the best the risk for developing CRC in patients with HP is not very high and equals that of adenomas.