Sentinel-node biopsy can replace axillary dissection in breast cancer with clinically negative lymph nodes. The study evaluated the accuracy of sentinel-node biopsy in predicting axillary lymph-node status. In 163 patients with operable breast cancer, microcolloidal particles labeled with technetium-99m were injected subdermally, and scintigraphic imaging was used to identify the sentinel node. A γ-ray probe was used to locate and remove the sentinel node during surgery. Pathological examination of all removed nodes confirmed the sentinel node's status. The sentinel node accurately predicted axillary lymph-node status in 97.5% of patients. In 38% of cases with metastatic axillary nodes, the only positive node was the sentinel node. In patients with tumours less than 1.5 cm, the sentinel node accurately predicted axillary-node status in all cases. The technique was reliable, with 98% identification of the sentinel node. The predictive value of the sentinel node was 97.5%, indicating that axillary dissection may be unnecessary if the sentinel node is disease-free. The study found that sentinel-node biopsy is a simple and effective method for identifying the sentinel node. The technique allows for accurate preoperative staging of the axilla, potentially avoiding unnecessary axillary dissection. However, there were some false-negative results, which may be due to micrometastases not detected in frozen-section examination. The study also noted that sentinel-node biopsy may not be suitable for multifocal tumours with extensive multifocality. The results suggest that sentinel-node biopsy can be used to spare patients from axillary dissection when the sentinel node is disease-free. The technique is easy to apply and has high accuracy, making it a promising alternative to traditional axillary dissection. The study also highlights the importance of further research to improve the accuracy of frozen-section examination and to develop more reliable methods for detecting micrometastases. Overall, the study supports the use of sentinel-node biopsy as a valuable tool in the management of breast cancer.Sentinel-node biopsy can replace axillary dissection in breast cancer with clinically negative lymph nodes. The study evaluated the accuracy of sentinel-node biopsy in predicting axillary lymph-node status. In 163 patients with operable breast cancer, microcolloidal particles labeled with technetium-99m were injected subdermally, and scintigraphic imaging was used to identify the sentinel node. A γ-ray probe was used to locate and remove the sentinel node during surgery. Pathological examination of all removed nodes confirmed the sentinel node's status. The sentinel node accurately predicted axillary lymph-node status in 97.5% of patients. In 38% of cases with metastatic axillary nodes, the only positive node was the sentinel node. In patients with tumours less than 1.5 cm, the sentinel node accurately predicted axillary-node status in all cases. The technique was reliable, with 98% identification of the sentinel node. The predictive value of the sentinel node was 97.5%, indicating that axillary dissection may be unnecessary if the sentinel node is disease-free. The study found that sentinel-node biopsy is a simple and effective method for identifying the sentinel node. The technique allows for accurate preoperative staging of the axilla, potentially avoiding unnecessary axillary dissection. However, there were some false-negative results, which may be due to micrometastases not detected in frozen-section examination. The study also noted that sentinel-node biopsy may not be suitable for multifocal tumours with extensive multifocality. The results suggest that sentinel-node biopsy can be used to spare patients from axillary dissection when the sentinel node is disease-free. The technique is easy to apply and has high accuracy, making it a promising alternative to traditional axillary dissection. The study also highlights the importance of further research to improve the accuracy of frozen-section examination and to develop more reliable methods for detecting micrometastases. Overall, the study supports the use of sentinel-node biopsy as a valuable tool in the management of breast cancer.