Radio-guided surgical biopsy for the diagnosis of suspected osseous metastases

Radioisotope bone scanning is frequently employed in staging malignancies. However, false positive results are common, and biopsy is usually required. In the absence of plain radiographic abnormalities or local symptoms, loca lization of the area of abnormal tracer activity at the time of open rib or sternum biopsy may be difficult. It often requires resection of a large po rtion of one or more ribs or other bones to assure that the target area was biopsied, and still the area in question is commonly missed. In this setti ng, the newly-developed, small gamma probe is now used as a tool to allow p recise intraoperative localization of increased tracer activity in the targ et bone. The use of gamma counting is an easy, highly accurate aid (100% se nsitivity) to localize areas of abnormal radioisotope uptake in suspected a symptomatic osseous metastases, usually for open biopsy of a rib. The use o f this technique obviates the need to obtain intraoperative localizing radi ographs to confirm accurate rib identification, thereby substantially decre asing operative time.