PTEN and PTEN hamartoma tumor syndrome: PTEN hamartoma tumor syndrome (PHTS), comprising Cowden, Bannayan–Riley–Ruvalcaba, and Proteus-like syndromes, is a rare multisystem disorder associated with increased lifetime risks for several cancer types due to pathogenic germline variants in the tumor suppressor gene PTEN. In addition to the increased cancer risk, PHTS is associated with developmental delay, overgrowth phenotypes, including macrocephaly, benign tumors, and skin abnormalities [76].