Abstract: A surgical instrument is disclosed for extracting specimens from an organ which comprises particularly configured cutting elements. In particular, the elements are so configured and arranged that they penetrate the organ by means of a substantially cylindrical incision and, immediately thereafter, perform a finishing cut which separates from the organ the cylindrical specimen corresponding to the incision.In one embodiment of the invention, the cutting elements employed are a punch and rotating guillotine or knife. In a second embodiment, the guillotine is replaced by a cutting element comprising two faced clamps, each being in the form of a chute, trough or convex member having a sharpened point and sharpened longitudinal edges.