Snapshot A 52-year-old woman with fair skin is concerned about a pink pearly lesion that is growing slowly on her cheek. She is a varsity water polo coach at her local high school and spends many hours under the sun. She admits to not using sunscreen consistently. Introduction Most common skin malignancy that rarely, if ever, metastasizes Epidemiology risk factors sun exposure prior ionizing radiation xeroderma pigmentosum common in fair-skinned individuals Commonly affects upper lip (squamous cell carcinoma typically affects lower lip) Presentation Physical exam pink, pearly-white, almost translucent dome-shaped nodule or papule overlying telangiectasias commonly develop raised or rolled border commonly ulcerate, bleed, and crust in the center (a non-healing ulcer) frequently on sun-exposed areas Evaluation Diagnosis by skin biopsy basophilic palisading cells on histology nests of basaloid cells in dermis Differential Squamous cell carcinoma Actinic keratosis Treatment Determined by size, location, and cosmetic considerations Surgical excision Mohs surgery reported cure rate between 97-99% Prognosis, Prevention, and Complications Prognosis if treated, typically very good risk of developing another basal cell carcinoma is 5-8% per year Prevention use sunscreen avoid sun exposure