Rough lesion on the thigh
An 87-year-old man presented to the Dermatology Clinic with a rough, tender 1-cm plaque on his right thigh that had first appeared 4 weeks earlier. It was firm to palpation with a thick surface of scale crust. The patient had a history of significant sun damage to his skin and basal cell carcinoma.
What’s your diagnosis?
A shave biopsy was performed and revealed a well-differentiated, invasive squamous cell carcinoma (SCC). Complete excision was performed with a 4-mm margin.
In the United States, SCC is the most common skin cancer in Black patients, as well as the second most common skin cancer overall. A history of UV exposure from the sun or artificial tanning beds is the most significant risk factor.1 Radiation, carcinogenic chemical exposure, longstanding inflammation caused by burns, and immunosuppression are also risk factors for SCC.
,When caring for a patient with SCC, the best initial work-up is a biopsy. A punch, shave, or excisional biopsy may all be appropriate if the dermis is adequately sampled. However, with a shave or shallow punch biopsy, thick keratin debris can unintentionally lead to a superficial sampling.
Cutaneous SCC should be treated by excision with 4- to 6-mm margins or Mohs microsurgery. Tumors that are smaller than 2 cm, lack aggressive histologic features, and are located in low-risk areas (eg, trunk or extremities) may be treated with standard excision. Larger tumors, recurrent tumors, higher risk histologic subtypes, and tumors on the head, neck, genitals, hands, or feet are candidates for Mohs surgery.
This patient was counseled to practice sun protection and to schedule regular follow-up visits every 6 months for the next 2 years.
Text courtesy of Jonathan Karnes, MD, medical director, MDFMR Dermatology Services, Augusta, ME. Photos courtesy of Jonathan Karnes, MD (copyright retained).