Dermatoheliosis
A lifetime of unprotected sun exposure had produced the following changes on the forearms of this 71-year-old rancher:
•Atrophy of epidermis and dermis, allowing the skin to tear and lacerate easily.
•The formation of multiple and, in this case, almost confluent actinic keratoses; these hyperkeratotic papules represent pre-cancerous focal atypia. Not only are these lesions uncomfortable, a small but significant percentage of them will undergo malignant transformation into squamous cell carcinoma.
•Solar purpura: these collections of trauma-induced extravasated red blood cells form very readily in such thin skin, but clear somewhat slowly for the same reason.
•Telangiectasias: these small red tortuous surface blood vessels are caused by a combination of chronic sun-induced vasodilatation, and thinning of the skin.
•Deep furrowing.
•Pronounced dryness.
•Mottled hyperpigmentary changes.
•Laxity/sagging, caused by the loss of dermal elasticity.
•Stellate scars and pseudoscars, which are common on these trauma-prone areas.
All of these skin changes represent dermatoheliosis.
For this patient, it is probably too late for sun protection, although it should be encouraged. At a minimum, he needs to be monitored regularly for skin cancer.
Treatment options for this patient include regular use of moisturizer and application of 5-fluorouracil cream to his arms twice a day for 3 weeks. The most prominent of the actinic keratoses could be treated with liquid nitrogen.