Cowden syndrome and Bannayan-Ruvalcaba-Riley syndrome share clinical characteristics such as hamartomatous polyps of the gastrointestinal tract, mucocutaneous lesions, and increased risk of developing neoplasms. Furthermore, both conditions and several other distinctive phenotypes are caused by mutations in the PTEN gene. For this reason Marsh et al. (1999) suggested that the spectrum of disorders be referred to as PTEN hamartoma tumor syndrome (PHTS). Approximately 80% of CS patients have PTEN mutations.
Confirmation of a clinical diagnosis, Carrier testing in unaffected family members