Extracutaneous primary Merkel cell carcinoma, a rare clinical entity

ABSTRACT Merkel cell carcinoma (MCC) is a rare and aggressive primary neuroendocrine skin cancer. Extracutaneous MCC with an unknown primary skin disease is challenging and intriguing. Histologic examination coupled with a wide panel of immunohistochemical stains is mandatory to establish the diagnosis. The tumour has a high local recurrence rate, metastasis and poor prognosis. We report two such rare cases, a case of an extracutaneous primary MCC involving the breast with axillary lymph node metastasis and another case of primary extracutaneous MCC of the lymph node.