Diffuse primary malignant melanoma of the upper gastrointestinal tract

Primary malignant melanomas of the GI tract are very rare. Their symptomatology is not specific. We report a 78-year-old Tunisian woman hospitalised with a 6-month history of recurrent abdominal pain, loss of appetite, weakness and weight loss. She had no personal history of cutaneous or ocular melanoma. Upper gastrointestinal endoscopy revealed multiple small, raised darkly pigmented tumours. Theses lesions were found in the oesophagus, the stomach, the bulb and the duodenum. Biopsy specimens were taken and histology showed the presence of melanocytic cells with abundant melanin pigment. Immunohistochemically, tumour cells were positive for HMB-45. Morphological examinations revealed hepatomegaly with multiple nodules with small lymph nodes at the celiac axis. All available diagnostic procedures failed to identify any other site of ocular or cutaneous melanoma, the present case was considered as primary GI melanoma. Palliative chemotherapy was not possible because patient was extremely cachectic and she died one month later.