Abstract: Aim: It is known that the most frequent location of tumor metastasis is in the axillary lymph nodes in subjects with breast cancer. Therefore, SLN detection and pathological evaluation are crucial for prognostic assessment and the selection of a therapeutical approach We designed this study to evaluate the efficacy of Tc-99m HIG lymphoscintigraphy and IGP on imaging SLN localization in patients with early stage (stage 1-2) breast cancer. Materials and methods: Fifteen patients with early stage breast cancer were included in this study. A peritumoral injection of Tc-99m HIG (750 µCi /0.1 ml in each injector) was given to four quadrants around the tumor in all patients before the operation. Dynamic images were taken just after the injection for a duration of 30 minutes at 15 second intervals. Anterior and lateral static images were taken from the thoracic regions following dynamic images for a duration of 2 hours until detection of SLN. In all the patients, before the operation, background counts were taken by IGP from the injection area, axilla, intramammarial region and thigh. Then, 5 ml of patent blue was injected peritumorally in all subjects. Attention was paid to ensure that the counts taken by IGP during the operation (invivo counting) should be twofold the patient's background activity (thigh background). After extracting the tissue (exvivo counting) the count should be at least tenfold of the patient's background activity. We also examined to determine the specimen whether or not it contained blue color. Then, this lymph node was accepted as an SLN and was sent for histopathological examination. Results: We performed lymphoscintigraphy on 14 patients. In 12 of the tumors SLN was detected in the axiller region and in 2 tumors both in the axiller and in the intramammarial region. All the patients underwent a patent blue violet injection and IGP count during the operation. In 14 of these patients, patent blue retention in SLN was seen. In all the patients SLN was detected by IGP. The histopatological examination of SLN detected, 6 of these patients (%40) had metastasis in the SLN node. In a further examination it was found that 4 of these 6 patients also had axillary metastasis. However, in one patient axiller lymph nodes metastasis other than SLN was seen. Eight of the 15 patients had no metastasis either in SLN or the axillary region. As a results, we concluded that Tc-99m HIG was a suitable agent for the SLN detection by lymphoscintigraphy and IGP in breast cancer patients.