A CASE OF MALIGNANT AMELANOTIC MELANOMA WITH ITS PROBABLE ORIGIN IN THE INTESTINE

Abstract

A case of malignant amelanotic melanoma of the small intestine in a 28-year-old man is described. Occasionally the patient experienced epigastric pain since 3 months earlier, and was noted to be anemic on his visit to the department of internal medicine. However, abdominal echo and upper gastrointestinal series revealed no abnormalities. On November 16, 1990, however, the patient was admitted to the department because of acute upper abdominal pain. On admission abdominal ultrasonography showed a low echoic tumor shadow in the center of the abdomen and the inner part of the tumor appeared as concentric laminated structure, which corresponded to the CT findings. With the diagnosis of intussusception, an emergency operation was carried out. In the ileum an intussusception involving a 3 cm tumor was recognized, and a partial resection of the small intestine was performed. Histologically, a poorly differentiated carcinoma was suspected. As anemia did not ameliorate after surgery, X-ray examination of the small intestine was conducted and disclosed a lot of tumorous lesions in the jejunum. Laparotomy was performed again for partial resection of the small intestine. Histologically, the tumor was diagnosed as malignant amelanotic melanoma. Chemotherapy with DTIC, ACNU, and VCR was carried out. The patient recovered his daily activities, as of 6 months after the operation.