If the doctor suspects melanoma, a biopsy will be performed. A biopsy is a test that involves removing the growth and analyzing it under a microscope. The method of biopsy depends on the size and shape of the growth. If it's a small mole or growth, the doctor will try to remove the whole growth in what's called an excisional biopsy. If the growth is larger, a doctor will usually remove only a part of the growth. This is called an incisional biopsy. Doctors may use local anesthetic if necessary for either type of biopsy. Once the tissue is removed, the doctor will send it to a lab to determine whether melanoma is present.