Prognostic Value of FDG PET/CT Parameters in Patients With Advanced Biliary Tract Cancer Receiving Gemcitabine, Cisplatin, and Nab-Paclitaxel

Background: Although a phase 3 trial did not demonstrate a survival benefit for gemcitabine, cisplatin, and nab-paclitaxel (Gem/Cis/Nab-P) in advanced biliary tract cancer (BTC), favorable outcomes were observed in specific patient subgroups, notably those with locally advanced disease or gallbladder carcinoma (GBC). This study aimed to assess the prognostic value of FDG PET/CT-derived parameters in advanced BTC patients treated with the Gem/Cis/Nab-P regimen, thereby identifying potential PET/CT imaging biomarkers that may aid in predicting survival benefit. Patients and Methods: We conducted a retrospective analysis of 125 advanced BTC patients who underwent pretreatment FDG PET/CT followed by Gem/Cis/Nab-P therapy. From the PET/CT images, maximum standardized uptake value, metabolic tumor volume, and total lesion glycolysis (TLG) of primary tumors were quantified. The influence of these parameters on prognostic outcomes was determined. Results: Multivariate survival analysis identified TLG as an independent significant prognostic factor for both progression-free survival (PFS) and overall survival (OS) ( P <0.05). In subgroup analyses stratified by disease stage and TLG, patients with locally advanced disease and low TLG achieved the most favorable survival outcomes (median PFS, 18.4 months; median OS, not reached). Among tumor subtypes, TLG effectively differentiated PFS and OS in GBC patients, with the low TLG group exhibiting a median PFS of 11.7 months. Conclusions: TLG on pretreatment FDG PET/CT served as an independent prognostic biomarker for PFS and OS in advanced BTC. Locally advanced disease and low TLG, as well as GBC with low TLG, might be predictive of enhanced survival benefit from Gem/Cis/Nab-P therapy.