Mole, or nevocellular nevus, may occur from birth or some time in the life time. Most moles are benign. Melanoma and basal cell carcinoma are malignant skin cancer and may look like a mole. If one or more of the ABC rules apply, please see us to be checked with dermoscope, which is a noninvasive method that allows the in vivo evaluation of colors and microstructures of the epidermis, the dermoepidermal junction, and the papillary dermis not visible to the naked eye. The ABC rules are: Asymmetry (one half of the mole doesn’t match the other), Border irregularity, Color that is not uniform, Diameter greater than 6 mm (about the size of a pencil eraser), and Evolving size, shape or color.
If the mole forms a nodule, expands to a big size, or reveals a strange shape, pathological examination may be done with biopsy or excision, which is covered by Japanese health insurance. Excisions of multiple moles for the cosmetic purpose are not covered by Japanese health insurance.