Yuji Nakamoto

Prognostic utility of FDG PET/CT in advanced ovarian, fallopian and primary peritoneal high-grade serous cancer patients before and after neoadjuvant chemotherapy

In patients with advanced ovarian, fallopian and primary peritoneal carcinoma, complete interval debulking surgery (IDS) is often performed after neoadjuvant chemotherapy (NAC) to achieve long progression-free survival (PFS) and overall survival (OS). We aimed to investigate the utility of 2-deoxy-2-[F-18]fluoro-D-glucose (FDG) PET/CT in patients with these malignancies who underwent complete IDS. Between 2009 and 2017, twenty-two patients underwent FDG PET/CT scans before and after NAC. The highest SUVmax/peak (standardized uptake value), metabolic tumor volume (MTV) and total lesion glycolysis (TLG) for whole lesions were defined as target SUVmax/peak, tMTV and tTLG, respectively. We also calculated these reduction rates during NAC. These parameters were compared between the groups with platinum-free interval (PFI) > 12 months (n = 10) and those with PFI ≤ 12 months (n = 12). The PFS and OS were evaluated using these quantitative parameters, and in terms of the presence of visually detectable residual lesions after NAC. The target SUVmax/peak before NAC, the reduction rates in the target SUVmax, tMTV and tTLG were significantly higher in the group with PFI > 12 months than the shorter PFI group (p < 0.05). Especially in PFS, the higher reduction rates in the target SUVmax/peak, tMTV, and tTLG had an excellent prognostic stratification (p < 0.05) and the FDG visually negative group after NAC had a significantly better prognosis than the other group (p < 0.01). The reduction rate of FDG PET-based quantitative values and visual analysis after NAC demonstrated prognostic potential, especially in PFS.