A retrospective study was conducted from a review of the medical records of patients with early-stage, invasive breast cancer who underwent surgical treatment and sentinel node biopsy with a radiotracer from January 2008 to August 2012 at a single institution (221 patients included). The patients were grouped according to the time of (99m)Tc Dextran-500 injection, which was preoperatively (with lymphoscintigraphy) (81 patients) or intraoperatively (140 patients). The purpose of the report is to compare the results of sentinel node biopsy of early-stage breast cancer patients who were subjected to intraoperative (99m)Tc Dextran-500 injections with the patients who received preoperative injections. The following parameters were analyzed: clinical tumor staging, histological and pathological results, size and number of tumor foci, peritumoral vascular invasion, number of lymph nodes removed, size of lymph node metastasis and hormone receptor expression.There were no differences in sentinel lymph node localization whether (99m)Tc Dextran-500 was injected preoperatively or intraoperatively.
