PTEN-hamartomatous tumour syndromes

In addition to a wide variety of symptoms and signs, which can be manifest as Cowden (CS) and Bannayan-Riley-Ruvalcaba syndromes (BRRS), individuals with a PTEN mutation are commonly found to have polyps on upper or lower GI endoscopy.

These include adenomas, various hamartomas and other lesions, including lipomas, fibromas, as well as the ganglioneuromas characteristic of Cowden Syndrome. Whether these polyps can or do lead to colorectal cancer is uncertain, but lifetime risk of colorectal cancer is increased (9-32%) compared to the general population.

Genetics

A number of variant databases are available, including Zhejiang University Center for Genetic and Genomic Medicine and the Radboud University Medical centre in The Netherlands.

Risks

While a modest rise in risk for colorectal cancer has been estimated at 9-32% (with age of onset beginning in the late 30s), the major cancer risks for those with a PTEN mutation are breast, thyroid and endometrial.

Management

An American review with guidelines has recommended ascertainment colonoscopy at 35y and 55y, with polyp follow up as required.

European guidelines (2020) on PHTS recommend colonoscopy at age 35-40 years, with follow-up as required.

 

Content updated 30 December 2020