RESUMEN
Objective:To evaluate the value of 99Tc m-hydrazinonicotinamide-(poly-(ethylene glycol)) 4-E((poly-(ethylene glycol)) 4-c((Arg-Gly-Asp)fK)) 2 (3PRGD 2) imaging on predicting pathological complete response (pCR) outcomes to neoadjuvant chemotherapy (NAC) in patients with breast cancer and to compare it with 18F-FDG imaging. Methods:From October 2017 to October 2019, 41 patients (age: (61.5±7.8) years) who were diagnosed with stage Ⅱ and Ⅲ breast cancer and planned to receive preoperative NAC in the First Affiliated Hospital of Fujian Medical University and Xiehe Affiliated Hospital of Fujian Medical University were prospectively enrolled. All patients underwent both 99Tc m-3PRGD 2 and 18F-FDG imaging before NAC (baseline), and after the first and the fourth NAC cycle. The tumor/background ratio (T/B; 99Tc m-3PRGD 2) and SUV max ( 18F-FDG) in breast tumors and axillary lymph node (ALN) metastases were separately calculated. The relative T/B changes (ΔT/B 1, ΔT/B 2) and SUV max changes (ΔSUV max1, ΔSUV max2) after the first and the fourth NAC cycle compared to baseline were obtained. Patients underwent surgery after NAC and the pathology was used as the gold standard to determine whether patient achieved pCR. The predictive performance of ΔT/B and ΔSUV max regarding the identification of pCR or non-pCR was evaluated by using ROC analysis and the AUCs were compared by Delong test. Results:Of 41 patients, 13 (31.7%) were achieved pCR after NAC. For breast tumors, the AUCs of ΔT/B 1, ΔT/B 2, ΔSUV max1 and ΔSUV max2 were 0.827 ( P=0.001), 0.687 ( P=0.057), 0.859 ( P<0.001) and 0.713 ( P=0.030) respectively, and the AUCs of ΔT/B 1 and ΔSUV max1 had no significant difference ( z=0.33, P=0.740). For ALN metastases, the AUCs of ΔT/B 1, ΔT/B 2, ΔSUV max1 and ΔSUV max2 were 0.859 ( P=0.002), 0.778 ( P=0.014), 0.572 ( P=0.523) and 0.802 ( P=0.007) respectively, and the AUC of ΔT/B 1 was significantly higher than that of ΔSUV max1 ( z=2.10, P=0.035). Conclusion:The early relative changes of breast tumors and ALN metastases in 99Tc m-3PRGD 2 imaging during NAC can offer predictive information for pCR to NAC in patients with breast cancer, and early relative changes of ALN metastases in 99Tc m-3PRGD 2 imaging may have a higher predictive value for pCR than 18F-FDG imaging.