Mohs surgery is a medical procedure used to treat some types of skin cancer including basal cell and squamous cell carcinomas. Mohs surgeries are performed in stages on the same day to efficiently remove the cancerous cells while retaining as much healthy tissue as possible quickly and efficiently. The surgeon removes one layer of tissue at a time, performing an extensive microscopic analysis of the excised cells from each stage. The cycle of tissue removal and analysis is repeated until no cancer cells are visible.