Repeated USMLE Questions Step 1- 179

A 65-year-old farmer presents to the clinic for evaluation of a long time lesion on his forehead. During an examination for life insurance, the nurse noticed it and advised him to go to the clinic for evaluation. The lesion is 1.5 in diameter, tan and nodular with an adherent greasy scale. Microscopically, it shows atypical keratinocytes invading the dermis and presence of intercellular bridges between the tumor cells.

What is the most likely diagnosis?

A- Basal cell carcinoma

B- Langerhans cell histiocytosis

C- Malignant melanoma

D- Mycosis fungoides

E- Squamous cell carcinoma

Answer





This is a typical presentation of squamous cell carcinoma. Forehead is a common site due to direct exposure to sun. Gross and microscopic findings are typical for squamous cell carcinoma.

The correct answer is E