Role of 18F-Flurodeoxyglucose Positron-Emission Tomography/Computed Tomography in the Evaluation of Early Response to Neoadjuvant Chemotherapy in Patients with Locally Advanced Triple-Negative Breast Cancer.

Abstract

Background:Response evaluation in locally advanced breast cancer is done through different methods ranging from clinical examination to magnetic resonance imaging, however evaluation with positron-emission tomography/computed tomography (PET/CT) in now being incorporated for the response evaluation. The aim of the present study is to correlate response to neoadjuvant chemotherapy (NACT) with PET/CT scan.Materials and Methods:The present study is a retrospective analysis of 30 locally advanced, triple-negative breast cancer patients. PET/CT scan was done pretreatment and post three and six cycles of NACT and was correlated with pathologic complete response (pCR). Responding disease was considered when there was at least a 50% reduction in the longest diameter.Results:The median pretreatment size of the breast lesion in CT scan was 3.9 ± 2.3 cm (2–12 cm) and maximum standardized uptake value (SUVmax) on PET/CT was 8.5 ± 5.5 (2.9–24). Among the responders, the median decrease in size of lesion was 3.2 ± 1.3 cm and median reduction in SUV of the tumor among was −8.1 ± 5.4 and was statistically significant when compared with nonresponders (P < 0.001). CT scan has 66% accuracy and PET has 82% accuracy at post three cycles NACT in predicting the pathological response. PET/CT had higher sensitivity and specificity when compared with CT findings alone in response evaluation.Conclusion:PET/CT scan can be considered as a sensitive tool for predicting pCRs and further larger trials are required to establish these findings.