Individuals with germline PTEN mutations have an inherited cancer syndrome known as PTEN hamartoma tumor syndrome (PHTS), which is characterized by increased risk of endocrine cancers including 85% lifetime cancer risk for the female breast, 35% thyroid and 28% endometrium; non-endocrine cancers are also components of the syndrome and include renal cancer (33% lifetime risk), colorectal (9%) and melanoma (6%) (Eng 2001, Tan et al. 2012). Here, PTEN is linked to PTEN hamartoma tumor syndrome.