Rare autosomal dominant condition- Mutation of the STK11 gene (tumor suppressor gene), expressed in a lot of tissues

Individuals develop hamartomous polyps throughout their GI tract and melanotic macules in their mouth, lips, genitalia, palms & soles.- Often asymptomatic. If big enough → abdominal pain, constipation, GI bleeding- Increased risk of extraintestinal cancers in GI tract, pancreas, breast, lung, ovaries/uterus, testes.

Polyp:- Benign outgrowths- Mostly in the small intestine- May be flat, pedunculated attached by stalk, sessile

Diagnosis: - Suspected in individuals with melanotic macules- Colonoscopy for pictures and biopsy → presence of hamartomas- Genetic testing for STK11 gene- Tumor marker screening: CEA for colon cancer, CA19-9 for pancreatic cancer, CA-125 for ovarian cancer