“…3 Malignant lesions should also be considered including basal cell carcinoma, squamous cell carcinoma, melanoma, sebaceous cell carcinoma, and primary neuroendocrine of the skin or Merkel cell carcinoma. 1,2,4 In our patient, the histologic differential diagnosis consisted of poorly differentiated primary eccrine carcinoma, metastatic poorly differentiated carcinoma, poorly metastatic carcinoid tumour, and Merkel cell carcinoma. 4,5 Immunohistochemical analyses were useful in this case and Merkel cell carcinoma was unlikely because tumour cells did not express cytokeratine 20.…”