The estimated incidence of PJS is approximately 1 in 50,000 to 1 in 100,000 worldwide, and germline mutations of the tumor suppressor genes serine/threonine kinase 11 or liver kinase B 1 (STK11/LKB1) are considered to be the cause of PJS [2, 3]. This evidence concerns the gene STK11 and Peutz-Jeghers syndrome.