The effect of positron emission tomography/computed tomography in axillary surgery approach after neoadjuvant treatment in breast cancer

OBJECTIVE: The aim of this study was to determine the role of positron emission tomography/computed tomography in the decision to perform axillary surgery by comparing positron emission tomography/computed tomography findings with pathology consistency after neoadjuvant chemotherapy. METHODS: Patients who were diagnosed for T1-4, cN1/2 breast cancer receiving neoadjuvant chemotherapy in our clinic between January 2016 and February 2021 were evaluated. Clinical and radiological responses, axillary surgery, and histopathological results after neoadjuvant chemotherapy were evaluated. RESULTS: Axillary involvement was not detected in positron emission tomography/computed tomography after neoadjuvant chemotherapy in 140 (60.6%) of 231 node-positive patients. In total, 88 (62.8%) of these patients underwent sentinel lymph node biopsy, and axillary lymph node dissection was performed in 29 (33%) of these patients upon detection of 1 or 2 positive lymph nodes. The other 52 (37.1%) patients underwent direct axillary lymph node dissection, and no metastatic lymph nodes were detected in 33 (63.4%) patients. No metastatic lymph node was found pathologically in a total of 92 patients without involvement in positron emission tomography/computed tomography, and the negative predictive value was calculated as 65.7%. Axillary lymph node dissection was performed in 91 (39.4%) patients with axillary involvement in positron emission tomography/computed tomography after neoadjuvant chemotherapy. Metastatic lymph nodes were found pathologically in 83 of these patients, and the positive predictive value was calculated as 91.2%. CONCLUSION: Positron emission tomography/computed tomography was found to be useful in the evaluation of clinical response, but it was not sufficient enough to predict a complete pathological response. When planning axillary surgery, axillary lymph node dissection should not be decided only with a positive positron emission tomography/computed tomography. Other radiological images should also be evaluated, and a positive sentinel lymph node biopsy should be the determinant of axillary lymph node dissection.