Atypical nevi, or abnormal moles, are moles that appear unusual to the eye. They may appear similar to melanoma. A person with an atypical nevus (abnormal mole) is at higher risk of melanoma, especially if they have many atypical nevi and/or a family history of abnormal moles and melanoma. The abnormal mole may appear in childhood or adulthood. It can be tested by a shave biopsy or shave removal that is performed in the doctor’s office. The mole is then submitted for examination under the microscope. If atypia (abnormal features) are found on the microscopic examination, an excision may be recommended.