Discussion

Primary malignant tumors of the small bowel account for less than 5% of GI malignancy. 14, 15 The most common malignancies involving the small bowel are metastatic. 16, 17 Small and large intestines are the most common sites for metastases from cutaneous malignant melanoma. Sixty percent of patients with malignant melanoma had GI metastases in an autopsy series. 18 Primary small-bowel melanomas are exceedingly rare19 and are associated with a worse prognosis in comparison with cutaneous tumors10 because of the rich vascular supply of GI mucosa and because detection of the disease is frequently made only at an advanced clinical stage.

The clinical presentation of small-bowel melanoma is similar to those of other smallbowel tumors and includes pain (70% of cases) from intestinal occlusion, anemia (20%–50%) from chronic blood loss, loss of weight (50%), and the presence of an abdominal palpable mass (25%). 2, 9, 20 Invagination, massive rectorrhagia, and perforation are less frequent findings. 2, 20