[en] Objectives:Scintigraphic detecting of SNs is widely accepted to avoid unnecessary axillary dissection in patients with breast cancer, but the application mode is still discussed controversially. Recently, subarelolar injection was recommended for avoiding anatomic condition. Aim of this study was an evaluation whether sensitivity to detect SNs after quadrant related subareolar (QSA) injection is different between 1cc and 3cc volume. Methods: 12 women with palpable BrCa and without clinical suspicion of lymph node metastases were investigated. One and 3 ml of Tc-99m antimony trisulfide colloid was injected into the QSA area, consecutively. And dynamic images for 5 minutes (1 frame/min) were acquired, respectively. All study was done within 15 minutes. Results: In 12 patients, SNs were detected in 2 patients after 1cc injection and 11 patients after 3cc injection. Sensitivity to detect SNs had a significant difference between 1cc and 3cc injection (16.7% vs 91.7%). Conclusions: Volume of tracer injection in QSA injection may be important for detecting SNs in breast cancer. We recommend using 3 cc of tracer in case of QSA injection