A biopsy instrument comprises an elongated flexible tube having a sharpened metal sleeve affixed to its distal end. An anvil member is affixed to the distal end of an elongated rod or wire which fits through the lumen of the tube and which is reciprocally moveable in the longitudinal direction by appropriately manipulating a handle device affixed to the proximal end of the tube. Affixed to the anvil member and electrically connected to the rod is an electrode. Means are provided for connecting an RF voltage between the electrode and metal sleeve for coagulating blood at the site where a tissue sample is excised from the internal wall of a body organ. The tissue sample is excised by positioning it against the sharpened edge of the metal sleeve and drawing back on the anvil to sever the sample and draw it into the interior of the sleeve where it remains until removed.