Merkel Cell Carcinoma With Gastric Metastases Presenting as a GI Bleed

Abstract

Introduction: Merkel cell carcinoma (MCC) of the skin is a rare malignancy that can present with lymph node metastases. This case is relevant as it is an unusual presentation of a rare disease where MCC is found in the stomach after a patient presents with a GI bleed. An 87-year-old Caucasian male presented to the ER with a 2 day history of fatigue, weakness and dark stools. He was recently diagnosed with MCC in April of 2011 which was treated with radiation. The diagnosis had come from biopsy of a firm, non-tender, mobile nodule near the right elbow. Physical exam during the patient’s emergency room presentation revealed a well developed man in no acute distress. The patient was hemodynamically stable. Rectal exam revealed guiaic positive stools. After undergoing laboratory studies, hemoglobin was found to be 8.7 mg/dL and he was transfused multiple units of packed red blood cells. An EGD was done which revealed a large polypoid lesion along the greater curvature of the stomach (Figure 1) as well as a smaller, 2 cm lesion in the body with slight ulceration. There was no evidence of overt bleeding, but there was evidence of oozing at the body. Biopsies from lesions revealed MCC. The diagnosis was confirmed with keratin, synaptophysin, and the cytokeratin (CK) 20 stains. A computed tomography (CT) scan was done of the chest, abdomen, and pelvis, which revealed a 2 x 1.4 cm mass anterior to the stomach. The patient subsequently underwent radiation therapy as it was decided that he was a poor surgical candidate. Four weeks later after a course of radiation therapy, a follow up EGD revealed a significantly smaller mass on the greater curvature of the stomach, which consisted of mostly prominent folds. Repeat biopsy of the area of the greater curvature of the stomach showed benign chronic gastritis with goblet cell metaplasia and immunochemical stains, which were negative for MCC. A literature review shows that only about 5 other reports document gastrointestinal metastasis. It should be of note that the metastatic disease was surprisingly responsive to radiation therapy and post-radiation treatment EGD revealed negative biopsies from the stomach.Figure 1