Case 1 is an 84-year-old Japanese man with previous medical history of hypertension, chronic hepatitis C infection, idiopathic thrombocytopenic purpura and colon polyps (tubular adenoma and tubulovillous adenoma). He had no mucocutaneous pigmentation or family history of PJS. An upper gastrointestinal endoscopy revealed a lobular polyp measuring 14 mm in diameter, in the superior duodenal angle (Figure ). Endoscopic mucosal resection was performed without complication and histological examination showed findings suggestive of a hamartomatous polyp--branching bundles of smooth muscle fibers covered by hyperplastic duodenal mucosa--with a focus of well-differentiated adenocarcinoma (Figure ). A colonoscopy and small-intestinal follow-through showed no other polyps.
Case 2 is a 76-year-old Japanese man who had been treated for prostate, rectal and lung cancer, with no mucocutaneous pigmentation or family history of PJS. An upper gastrointestinal endoscopy revealed a duodenal polyp measuring 15 mm in diameter in the second part of his duodenum (Figure ). Endoscopic mucosal resection was performed, and histological examination showed findings suggestive of a hamartomatous polyp (Figure ). A colonoscopy and small-intestinal follow-through showed no other polyps. After the endoscopic treatment, concomitant liver and thyroid cancers were found.