A study of sentinel node biopsy in T-1 breast cancer treatment: Experienceof 48 cases

Axillary clearance in breast cancer has been proven to be unnecessary in mo re than 50% of cases. Sentinel node biopsy (SNB) is a new technique that ca n be used to avoid unneccesary axillary clearance in breast cancer surgery. Our integrated team, consisting of surgeons, pathologists and nuclear medi cine physicians, studied 48 cases of T-1 breast cancer with lymphoscintigra phy-guided SNB. Before starting this study, the team performed 20 SNBs as a learning procedure. 500 mu Ci of Tc-99m-nanocoll in 0.2 mt were injected a round the lesion, under US or x-ray guidance if necessary. Static images in anterior, lateral and lateral oblique view collected at the end of a 20 mi n dynamic study were used to mark the SN on the skin. During surgery a gamm a probe was used to guide SN resection, and node invasion was assessed with cytokeratin immunohistochemistry. In 14 patients tracer uptake was observe d in a single node, in 30 patients in 2-4 nodes, whereas in four patients t he nodes were scintigraphically missed. Surgical resection was possible in 42 nodes out of 54. All but two patients with negative immunohistochemistry for cancer cell clusters showed metastasis-free axillary nodes. All patien ts with positive SNBs (13) showed involved axilla, in four patients the lym phatic drainage was towards the intramammary chain; one node was juxtaclavi cular and one node was intramammary in the upper outer quadrant. The overal l sensitivity of the method was about 80%, the specificity about 90% with a diagnostic accuracy about 80%, SNB is a promising method for surgical deci sion-making regarding axillary clearance in breast cancer. Adequate trainin g of an interdisciplinary team is needed in order to successfully perform S NB and assess SN invasion. Its unusual anatomic location can be encountered end technical care is necessary to correctly identify and remove them.