Surgical applications of gamma-detecting probes

The RIGS system is a technology which was developed to provide a more sensitive and accurate method of detecting colorectal cancer during surgery. One of the components of this system is the hand-held, gamma-detecting probe [Neoprobe Model 1000instrument; Neoprobe Corporation, Dublin, Ohio), used by the surgeon to identify preadministered, radiolabeled monoclonal antibody which has localized to dis- eased tissue. RIGSuses sound-directed gamma detection to identify and locate cancer which may not be seen or felt by the surgeon. The success of RIGS has been largely due to the remarkable sensitivity of the gamma- detecting probe in detecting small amounts oflow-energy radioactivity. This attribute has led to the use of the probe for other surgical applications including pre- and intraoperative lymphatic mapping, and parathyroid localization. Surgery for melanoma, breast cancer, parathyroid disease, and colorectal cancer has been af- fected by the increased use of the gamma-detecting probe both in clinical trials and practice. This chapter will review the many applications of this new technology.