Squamous cell carcinoma. A round nodule with central hyperkeratosis, firm and indolent. This lesion cannot be distinguished clinically from keratoacanthoma; it is easily distinguished from nodular BCC because BCC does not develop hyperkeratosis.
Fitzpatrick’s Color Atlas & Synopsis of Clinical Dermatology Klaus Wolff, Richard Allen Johnson, Dick Suurmond Copyright 2005, 2001, 1997, 1993 by The McGraw-Hill Companies. All Rights reserved.
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