RESUMEN
Peutz-Jeghers syndrome is a rare autosomal dominant disorder defined by harmatomatous polyps of the gastrointestinal tracts and the occurrence of melanin spots on the lips(oral mucosa), hands and feet. This syndrome is associated with a variety of gastrointestinal and extraintestinal neoplasms, both benign and malignant. A 28-year old male was admitted to our hospital with abdominal pain and nausea for two months. He had melanin spots involving his lips, buccal mucosa, hands and feet. A small bowel series showed luminal obstruction at the forth portion of the duodenum. And abdominal CT scan showed target-like mass suggesting intussusception on the small bowel. On laparotomy, there was an annular constricting mass adherent to retroperitoneum with metastasis to preaortic lymph nodes. Palliative duodeno-jejunostomy was performed. The histologic finding disclosed signet-ring cell type adenocarcinoma.