Although needle-wire localization is the most commonly used localization technique for nonpalpable breast lesion biopsy, the technique of radioguided occult lesion localization (ROLL), is becoming increasingly used for open-surgery diagnosis in such cases. Sentinel lymph node biopsy(SLNB) is based on the hypothesis that lymphatic drainage from a tumor reaches the sentinel node(SLN) first and that it can be identified accurately and removed. If SLN exactly reflects the lymph-node status, a negative SLN for metastasis might allow complete axillary lymph node dissection (ALDN) to be avoided.