Small cell variant of malignant melanoma masquerading as lymphoma on fine‐needle aspiration cytology: A case report

The morphologic and immunohistochemical diversity of malignant melanoma is well known to pathologists but despite this widespread awareness the diagnosis remains a constant challenge, particularly when a noncutaneous or metastatic tumor is evaluated by fine‐needle aspiration cytology. We present a case of the small cell variant of malignant melanoma mimicking lymphoma in a 78‐year‐old previously healthy male who presented with multiple pulmonary masses and a right‐sided pleural effusion. This particular case was also immunoreactive for the hematopoietic marker CD43, a feature not previously reported in malignant melanoma. Cytologic, histologic, and immunohistochemical features of this case are presented and discussed. Diagn. Cytopathol. 2012. © 2011 Wiley Periodicals, Inc.