Role of 18 F-PET/CT in Predicting Prognosis of Patients With Breast Cancer After Neoadjuvant Chemotherapy

Background Breast cancer can be assessed preoperatively and postoperatively using 18 F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT). We prospectively analyzed the maximum baseline standardized uptake value (SUVmax) derived from FDG PET/CT to predict the outcomes after neoadjuvant chemotherapy (NAC) for breast cancer. Patients and Methods We assessed 130 consecutive female patients with primary breast cancer (mean age, 53.9 years) using PET/CT before and after NAC. The SUVmax before (pre-SUVmax) and after (post-SUVmax) NAC and the SUVmax reduction rates (ΔSUVmax) after NAC with sequential anthracyclines and a taxane were assessed to predict the pathologic complete response (pCR) and prognosis. Results Of the 130 patients, 30 (23.1%) achieved a pCR. The pCR rate of the patients with human epidermal growth factor receptor 2-positive (HER2 + ) and triple-negative (TN) breast cancer was 52.8% and 40.0%, respectively. In contrast, only 1.4% of those with estrogen receptor-positive and HER2 − cancer achieved a pCR. The post-SUVmax correlated closely with the pCR (area under the curve, 0.700) but not with the pre-SUVmax and ΔSUVmax (area under the curve, 0.414 and 0.589, respectively) in patients with HER2 + and TN breast cancer. The post-SUVmax was associated with the pCR ( P = .019), and multivariate analysis selected post-SUVmax as a significant prognostic factor ( P = .014). The post-SUVmax correlated significantly with recurrence-free survival and recurrence ( P = .026, log-rank test). Conclusion The SUVmax determined after NAC using FDG PET/CT can predict for the pCR and the prognosis of patients with operable HER2 + and TN breast cancer. In the future, additional chemotherapy will be applied according to the post-SUVmax after standard NAC to achieve a pCR or omit surgery.