Abstract: A probe for detecting and removing radioactively tagged tissue, e.g., a sentinel lymph node, within the body of a living being. The probe is arranged to be inserted through a small percutaneous portal into the patient's body and is movable to various positions adjacent the tagged tissue to detect the presence of radiation therefrom so that the probe can be positioned immediately adjacent that tissue to ensnare or trap it. The probe can then be removed from the being's body, carrying the tagged tissue with it. The probe may be constructed to make use of a scintillation crystal, a collimator, adjustable or fixed, and a backshielding lightpipe.