A dermatologist is a physician who performs Mohs surgery, according to the American Academy of Dermatology. A dermatologist specializes in treating problems of the skin, hair, nails and mucous membranes.
Mohs surgery is a special surgery that treats skin cancer, especially basal cell and squamous cell skin cancer, according to Skin Cancer Foundation. Even a certified dermatologist needs extra training to perform it properly, according to the American Academy of Dermatology.
In Mohs surgery, the lesion is removed layer by layer, along with a margin of healthy skin, according to Skin Cancer Foundation. The layers are examined under a microscope right away, and more layers are removed until no more of the cancer remains.