Gastrointestinal Metastatic Melanoma: The Key for Diagnosis.

Abstract

An 80-year-old Caucasian woman was hospitalized with a 2-month course of intermittent fever (max. 38 ° C), asthenia, weight loss (12%), anorexia and nausea. Her medical history includes breast cancer submitted to radical mastectomy and axillary lymph node dissection, papillary thyroid carcinoma and pulmonary and ocular tuberculosis that had been treated more than 5 years previously. She had heart failure, arterial hypertension, dyslipidaemia and obesity under treatment. Physical examination showed obesity and left upper limb lymphedema. Abdominal and rectal examinations were unremarkable. A laboratory study revealed iron deficiency anaemia with haemoglobin 10 g/dL and ferritin 10 ng/mL (normal = 10–120 ng/mL), elevated lactate dehydrogenase 1,379 U/L (normal <247 U/L), aspartate transaminase 59 U/L (normal <31 U/L), alkaline phosphatase 185 U/L (normal = 30–120 U/L), C-reactive protein 21.9 mg/dL (normal = 0–0.5 mg/dL) and a normal procalcitonin value. A bacterial, mycobacterial, viral or fungal infectious disease was excluded by blood, urine and sputum cultures. A thoracic abdominal and pelvic computerized tomography (CT) scan was negative for malignant disease. During hospital stay she presented with intense nausea and vomiting during most meals. A red blood cell transfusion was necessary due to progressive decrease in haemoglobin. Upper endoscopy was performed showing multiple black nodular lesions in the stomach and duodenum (Fig. 1). Narrow-band imaging revealed the presence of black patches on the top of these nodular lesions (Fig. 2). Histopathological examination showed an epithelioid malignant injury with intense and diffuse HMB45 expression suggestive of pigmented melanoma (Fig. 3). The diagnosis of gastrointestinal