68 Ga-Labeled Fibroblast Activation Protein Inhibitor PET/CT for the Early and Late Prediction of Pathologic Response to Neoadjuvant Chemotherapy in Breast Cancer Patients: A Prospective Study

作者：Ling Chen, Shan Zheng, Linying Chen, Sunwang Xu, Kunlin Wu, Lingjun Kong, Jiajie Xue, Xiangjin Chen, Weibing Miao, Youzhi Zhu · 发表于：Journal of Nuclear Medicine · 年份：2023 · DOI：10.2967/jnumed.123.266079 · 被引用次数：33 · 研究领域：Peptidase Inhibition and Analysis、Radiopharmaceutical Chemistry and Applications、Medical Imaging Techniques and Applications

68 Ga-labeled fibroblast activation protein inhibitor ( 68 Ga-FAPI) PET/CT has demonstrated promising clinical results, with a higher SUV max and tumor-to-background ratio (TBR) in breast cancer (BC) patients than 18 F-FDG PET/CT. Here, we aimed to evaluate the suitability of 68 Ga-FAPI PET/CT for the early and late prediction of the pathologic response to neoadjuvant chemotherapy (NAC) in BC. Methods: Twenty-two consecutive patients with newly diagnosed BC and an indication for NAC were prospectively included. All patients underwent standard chemotherapy and 68 Ga-FAPI PET/CT at baseline, after 2 cycles of NAC (PET2), and 1 wk before surgery (PET3). SUV max was measured in the primary tumor region and positive regional lymph nodes. The expression of fibroblast activation protein in the primary lesion was analyzed by immunohistochemistry. Results: Seven patients (31.8%) achieved a pathologic complete response (pCR), and 15 (68.2%) had residual tumors. Thirteen patients (59.1%) showed concentric withdrawal of the primary tumor, and 9 (40.9%) showed diffuse withdrawal. Between PET2 and PET3, the ΔSUV max of the primary tumor ( R 2 = 0.822; P = 0.001) and metastatic lymph nodes ( R 2 = 0.645; P = 0.002) were significantly correlated. The absolute values of SUV max and TBR at PET2 and PET3 were lower in patients with pCR than in those without pCR ( P < 0.05). Moreover, a larger ΔSUV max at any time point was strongly associated with pCR ( P < 0.05). Si...