[Unusual presentation of malignant melanoma of the small intestine].

2 patients with unusual presentations of malignant melanoma involving the small intestine, a 75-year-old woman and a 78-year-old man, are described. One underwent laparotomy for diagnosis and removal of a retroperitoneal mass, with no preoperative evidence of the primary disease. The other underwent emergency laparotomy for small bowel obstruction due to intussusception, which was found to result from a metastatic melanoma. A melanoma had been completely resected from the patient's thigh a month previously, but full investigation before the operation for intussusception failed to establish the diagnosis. Malignant melanoma tends to spread to the small intestine, but tumors of this organ are very rare. Preoperative diagnosis is important since it may improve the outcome of surgical intervention, as well as the prognosis in general.