Abstract: Apparatus for safely and accurately positioning the fingertip of a physician (or technician) performing a biopsy procedure, e.g., to excise a core tissue samples of the male prostate or other internal organs, to avoid injury (e.g., a needle stick) from the sharpened distal end of a biopsy needle assembly. Such apparatus comprises an open tubular member defining an elongated passageway through which a biopsy needle assembly, when actuated, can be made to pass and to extend a predetermined distance along an external path in order to effect the core sampling of a biological mass of interest. The tubular housing supports a safety flange at its distal end, such flange having a flat surface adapted to be engaged by the fingertip of the physician prior to actuation of the biopsy needle assembly.