IMPACT OF LYMPHOSCINTIGRAPHY ON SENTINEL NODE IDENTIFICATION WITH TECHNETIUM-99M-COLLOIDAL ALBUMIN IN BREAST-CANCER

Identification of the sentinel node by using colloidal tracers and a g amma probe or lymphoscintigraphy could be an effective alternative for the complicated original dye-oriented approach, We studied the sentin el node detection rate using early and delayed imaging in breast cance r patients. Methods: Thirty-seven patients were imaged 2 hr and 18 hr after peritumoral injection of Tc-99m-colloidal albumin. Preoperativel y, axillary foci were located with a handheld gamma probe that was als o used to isolate radiolabeled nodes from the axillary dissection spec imens. The predictive value of the sentinel node for the axillary tumo rstatus was evaluated with histological examination. Results: Two and 18 hr after injection, lymphoscintigraphy revealed one to three separa te axillary lymph nodes in 33 and 34 patients, respectively. In 30 pat ients the axillary foci were easily localized with the gamma probe pre operatively. In all 34 patients (92%), with visualized axillary foci, at least one radioactive sample could be retrieved using the gamma pro be (total 53 samples). Metastases were found in the sentinel nodes of 11 patients, in seven of 11 being the only tumor-positive lymph node i n the axilla, There were no false-negative sentinel nodes. Conclusion: The selective targeting and prolonged intranodal retention of Tc-99m- colloidal albumin allows successful sentinei node identification in mo st (92%) patients.