Rapidly growing gastric metastasis of Merkel cell carcinoma, an unusual cause of melena

Merkel Cell Carcinoma with Gastric Metastasis, a Rare Presentation: Case Report and Literature Review

INTRODUCTION

Merkel cell carcinoma (MCC) is an infrequent, but highly aggressive neuroendocrine neoplasm of the skin with a propensity for recurrence and metastasis. We report a rare case of gastric metastatic localization of this cancer by focusing on the diagnostic, clinical, and surgical approach to the patient.

CASE REPORT

Clinical presentation begins with a peripheral lymphadenopathy whose immunohistochemical characterization identifies the lymphatic dissemination of the disease. Gradually, the patient develops a severe anaemic state which requires several blood transfusions and surgical gastric resection to remove a large bleeding lesion of the antral region. The histopathological analysis of the specimen confirms the metastatic origin from MCC, but the primitive lesion remains unknown.

DISCUSSION

Since this clinical situation is very rare, we conducted a review of the literature selecting the few cases reported, in order to evaluate the current knowledge on this topic. Metastatic involvement of the stomach from Merkel cell carcinoma is a rare presentation of this disease progression with a frequent delay in formulating the correct diagnosis and in further treatment which may be life-threatening for the patient. As regards the local treatment, there is no specific guideline, and the therapeutic indication should be tailored on the specific case.