Pathophysiology

Question:

A 72-year-old man who is a retired construction worker comes to the physician because he has had a lesion on his face for 3 months. Physical examination shows a 6-mm, red, ulcerated lesion with heaped borders. A biopsy specimen of the lesion shows atypical, dysplastic keratinocytes within the epidermis and dermis. Which of the following is the most likely diagnosis?

Correct Answer: E.  Squamous cell carcinoma

Skin cancer comes in three major forms – squamous cell carcinoma (SCC), basal cell carcinoma (BCC), and melanoma. This patient’s presentation and histology suggest squamous cell carcinoma. In general, a lesion described as ulcerated or with heaped borders is cancerous until proven otherwise. The atypical and dysplastic keratinocytes indicate a squamous cell origin.

Actinic keratosis is a thick, scaly lesion that a predecessor lesion to SCC. It would be fair to consider in this patient except that the clinical presentation describes a lesion that has progressed much further.

Melanoma is a neoplasm of melanocytes. Melanoma should be associated with ABCDE – Asymmetry, irregular Borders, multiple Colors, Diameter greater than 5mm, and Evolution of a pre-existing nevus. Melanoma is more common in younger people.

Mycosis fungoides is a presentation of cutaneous T-cell lymphoma; this patient’s histology is not suggestive of such a rare diagnosis.