Radioguided localization of occult breast lesions

Clinically occult breast lesions are found with increasing frequency by breast screening, and several methods have been used to locate suspicious occult lesions prior to excision. We have developed a new localization technique called ROLL (radioguided occult lesion localization) in which a small quantity of Tc-99m-labelled colloidal serum albumin is injected into the lesion during mammographic or ultrasonic examination. Correct positioning is checked by scintigraphy. A gamma detecting probe is then used to locate the lesion and guide its surgical removal. We report on the first 225 patients in whom we have employed this technique: all had non-palpable breast lesions identified by mammography or ultrasound as clusters of microcalcifications or small opacities. Pathology revealed 134 cancers, 133 of which were treated by breast-conserving surgery. In all but 2 cases (99%), radiolabelling coincided with the lesion site. X-radiography verified that the specimen removed contained all of the lesion. Removal of clinically occult breast lesions is greatly facilitated by the gamma probe, which locates the skin projection accurately, allowing choice of the most appropriate incision, and which can be employed continuously during surgery.