Role of gamma probe-assisted intraoperative sentinel lymph node evaluation in predicting axillary breast cancer metastasis after neoadjuvant chemotherapy

摘要

Objective Intraoperative sentinel lymph node biopsy is a universally accepted technique to identify patients who are candidates for axillary lymph node dissection during breast cancer surgery. However, there is controversy over its use in patients who underwent preoperative neoadjuvant chemotherapy. This study aimed to examine the diagnostic value of gamma probe-assisted intraoperative sentinel lymph node examination with frozen section in breast cancer patients who had undergone preoperative neoadjuvant chemotherapy. Methods This retrospective study included 94 tumors diagnosed with stage IIA, IIB or IIIA invasive breast cancer with locoregional lymph node metastasis who underwent surgical treatment after neoadjuvant chemotherapy. Intraoperatively, axillary sentinel lymph node sampling was done using radioactive colloid and gamma probe and materials were examined with frozen section method. Patients with positive sentinel nodes underwent axillary resection. Histopathological examination of all surgical samples was done postoperatively. Results In 87 of 94 tumors (92.6%), a sentinel lymph node could be identified using the method. The sensitivity, specificity and accuracy of the method for predicting axillary macro metastasis were 85.7, 86.5 and 86.2%, respectively, with 5.7% false negative rate. Conclusions Sentinel lymph node identification using preoperative scintigraphy and intraoperative use of gamma probe seems to be a feasible and efficient method in terms of differentiating patients that require axillary lymph node dissection during breast cancer surgery, even when they have received neoadjuvant chemotherapy. Further large prospective studies allowing subgroup analyses are warranted.