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Combined Merkel cell carcinoma and atypical fibroxanthoma
Summer R Youker1, Elizabeth M Billingsley
1Department of Dermatology, St. Louis University, St. Louis, Missouri 63104, USA. sumyou@hotmail.com
Background:
Although there are reports of squamous cell carcinoma arising within and adjacent to Merkel cell carcinoma, and one report of an atypical fibroxanthoma-like tumor arising in an irradiated recurrent Merkel cell carcinoma, there have previously been no reports of an immunohistochemically verified atypical fibroxanthoma occurring in conjunction with a Merkel cell carcinoma.
Objective:
We report on a neoplasm with distinct features of both Merkel cell carcinoma and atypical fibroxanthoma.
Methods:
Histologic and immunohistochemical evaluations were performed.
Results:
Our results verify the finding of a combined Merkel cell carcinoma and atypical fibroxanthoma.
Conclusion:
This case is an interesting and unusual combination of tumors. The origin of the Merkel cell carcinoma is revisited. Debated origins include neuroendocrine, epithelial, and pleuripotent stem cell.
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