punch biopsy

:  a biopsy in which a small, round sample of tissue (such as skin) is obtained by using an instrument with a circular blade An incisional or punch biopsy that includes the most raised (or most deeply pigmented) portion of the lesion is acceptable if the lesion is too large for complete simple excision or is at a site where complete removal would cause substantial disfigurement.—Howard K. Koh, The New England Journal of Medicine, 18 July 1991