Dermatology & Skin Cancer Surgery Center offers cryosurgery, also known as cryotherapy, as an option for precancer treatment. This is the method of taking liquid nitrogen and using it to destroy abnormal tissue. Externally, it is used to treat tumors found on the skin, lesions, and moles that show early stages of skin cancer, and actinic keratosis or precancerous skin growths. Liquid nitrogen is administered directly to the skin using a cotton swab or spray and the growth is removed. Most patients are able to leave the office shortly after the procedure.