A 76 year old male with an unusual presentation of merkel cell carcinoma.

INTRODUCTION: Merkel Cell Carcinoma is an aggressively malignant, neuroendocrine-derived, cutaneous neoplasm that commonly affects sun-exposed areas of the elderly population. MCC typically presents as a rapidly enlarging, painless nodule that is red to purple in color and located on sun exposed areas such as the head, neck and arms. Although rare, cases of MCC on non-sun exposed skin have been documented and typically have a worse prognosis.

PRESENTATION OF CASE: We report an atypical case of Merkel Cell Carcinoma originating in a non-sun exposed area of the body with evidence of distant metastasis. A 76-year-old male presented with complaints of a firm lesion in his left gluteal fold.

DISCUSSION: Clinical diagnosis of MCC is usually made from a combination of history and physical, skin and nodal examination, biopsy sample with H&E prep, and immunopanel. Treatment according to the National Comprehensive Cancer Network(®) (NCCN(®)) is directed by lymph node involvement and metastasis.

CONCLUSION: With initial unsuccessful treatment, his lesion was excised and pathological evaluation reported Merkel Cell Carcinoma (MCC). Despite further surgical excision and adjuvant chemotherapy, increased hyper metabolism was found in the left descending colon and left prostate of unknown etiology. There have been reports of metastasis of primary MCC to the small bowel mesentery; therefore new focal hyper metabolism cannot be delineated precisely as unrelated to MCC until biopsy and histochemical staining are performed.