FaCD Online Syndrome Fact Sheet

Last updated: 24 Sep 2009

Name: Hyperplastic-Adenomatous Polyposis syndrome

Synonym: HAPS

Mode of Inheritance: spor/ multifact?/ de novo?

Tumor features

colon cancer
colorectal adenomas
colorectal hyperplastic polyps


Place and Simmang[1] reported on 6 patients aged 41-75 with 50-100 hyperplastic polyps associated with adenomas, and in 3 patients associated with colon cancer. The patients were retrospectively selected by the fact that they had more than 50 hyperplastic polyps. Family history was negative. The authors refer to this condition as hyperplastic-adenomatous polyposis syndrome (HAPS).
In a series of 15 patients with hyperplastic polyposis as defined by the WHO International Classification, Ferrández et al observed common as well as large hyperplastic polyps, adenomas and serrated adenomas. None of these patients had a first-degree relative with colon cancer.[2]. In general, adenomas are not uncommon in patients with many hyperplastic polyps. HAPS should presently be considered part of the heterogenous hyperplastic polyposis and hereditary mixed polyposis type I and type II spectrum.


[1] Place RJ, Simmang CL. Hyperplastic-adenomatous polyposis syndrome. J Am Coll Surg 1999; 188(5):503-507.
[2] Ferrández A, Samowitz W, DiSario JA, Burt RW. Phenotypic characteristics and risk of cancer development in hyperplastic polyposis: case series and literature review. The American journal of gastroenterology 2004; 99(10):2012-8.