A 56-year-old man comes to the office due to a yearlong history of skin lesions on the cheeks, forehead, and scalp. Except for their appearance, the lesions do not trouble the patient. Medical history includes androgenic alopecia and poorly controlled type 2 diabetes mellitus. Vital signs are normal. Findings on the left cheek are shown in the exhibit. Similar lesions appear on the right cheek, forehead, and scalp. Which of the following is the most likely diagnosis in this patient?

Question

A 56-year-old man comes to the office due to a yearlong history of skin lesions on the cheeks, forehead, and scalp.  Except for their appearance, the lesions do not trouble the patient.  Medical history includes androgenic alopecia and poorly controlled type 2 diabetes mellitus.  Vital signs are normal.  Findings on the left cheek are shown in the exhibit.  Similar lesions appear on the right cheek, forehead, and scalp.  Which of the following is the most likely diagnosis in this patient?

Quizplus · Accepted Answer

11ec25c8_d371_7dc4_bc81_af50a3c53625_MD0003_00 This patient has actinic keratosis (AK), a precursor to squamous cell carcinoma (SCC). AK presents as chronic, scaly papules or plaques with a characteristic sandpaper-like texture; it most commonly occurs in older, fair-skinned patients. Chronic sun exposure is the major risk factor, with lesions primarily affecting sun-exposed areas (eg, scalp, face); the surrounding skin often displays features of solar damage (eg, telangiectasias, deep wrinkles), as in this patient. deep wrinkles AK is diagnosed based on appearance, but biopsy is indicated to rule out SCC for lesions exhibiting high-risk features (eg, >1 cm, induration/ulceration, rapid growth, therapeutic failure). Isolated lesions can be treated with focal cryotherapy (eg, liquid nitrogen), but involvement of a large area, as seen in this patient, requires field therapy with topical agents (eg, 5-fluorouracil). (Choice B) Psoriasis presents as erythematous plaques with silver scales. The lesions are pruritic and most commonly occur at the extensor surfaces (eg, knees). erythematous plaques (Choice C) Seborrheic dermatitis typically presents with mildly pruritic, erythematous plaques with greasy, yellow scales on the scalp, central face, and ears. Discrete, isolated scaly papules are atypical. yellow scales (Choice D) Seborrheic keratoses typically present as brown, stuck-on papules with rough surfaces. stuck-on papules (Choice E) Tinea facialis presents as an erythematous annular patch or plaque with light, diffuse scales. plaque Educational objective: Actinic keratosis is characterized by scaly papules or plaques with sandpaper-like texture on sun-exposed areas (eg, face, scalp). Lesions are precursors to squamous cell carcinoma and are treated with cryotherapy or topical agents (eg, 5-fluorouracil), depending on distribution. References: Current perspectives on actinic keratosis: a review. (http://www.ncbi.nlm.nih.gov/pubmed/27500794)

A 56-Year-Old Man Comes to the Office Due to a Yearlong