Laser therapy works by delivering highly concentrated light to the target area. The laser's intense energy can cut through tissue, vaporize abnormal cells, or seal blood vessels. In cancer treatment, lasers can be used to shrink or destroy tumors and precancerous growths, either on the surface of the body or inside the body. Various types of lasers, such as CO2 and Nd:YAG, are used depending on the nature of the cancer.