Germline PTEN Mutation Cowden Syndrome: An Underappreciated Form of Hereditary Kidney Cancer

Renal cell carcinoma is an underappreciated feature of Cowden syndrome. As most patients lack a prior family history or a distinctive renal cell carcinoma histology, recognition of the associated nonrenal features should target referral for genetic counseling. PTEN loss of heterozygosity is common in Cowden syndrome renal tumors. Because loss of PTEN can activate mTOR and mTOR inhibitors are Food and Drug Administration approved to treat renal cell carcinoma, these agents have clinical potential in renal cell carcinoma associated with Cowden syndrome.