Cryosurgery (also called cryotherapy) is the process of destroying diseased skin cells (lesions) by freezing them with liquid nitrogen. It may be used to treat cancer or skin problems, such as warts or moles.

When cryosurgery is used to treat skin problems, the skin may first be numbed with a local anesthetic. The liquid nitrogen is applied or sprayed onto the lesion and the immediate surrounding tissue. The application may be repeated.

For treating cancer inside the body, a probe may be inserted into the tumor to freeze and destroy the cancer.