How do physicians diagnose skin cancer?
A skin examination by a dermatologist is the way to get a definitive diagnosis of skin cancer. In many cases, the appearance alone is sufficient to make the diagnosis.
A skin biopsy is usually used to confirm a suspicion of skin cancer. This is performed by numbing the area under the tumor with a local anesthetic such as lidocaine. A small portion of the tumor is sliced away and sent for examination by a pathologist, who looks at the tissue under a microscope and renders a diagnosis based on the characteristics of the tumor.