Prognostic significance of standardized uptake value on preoperative ¹⁸F-FDG PET/CT in patients with ampullary adenocarcinoma

Purpose: The purpose of this study was to investigate the prognostic value of ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) in patients with ampullary adenocarcinoma (AAC) after curative surgical resection. Methods: Fifty-two patients with AAC who had undergone ¹⁸F-FDG PET/CT and subsequent curative resections were retrospectively enrolled. The maximum standardized uptake value (SUV_max) and tumor to background ratio (TBR) were measured on ¹⁸F-FDG PET/CT in all patients. The prognostic significances of PET/CT parameters and clinicopathologic factors for recurrence-free survival (RFS) and overall survival (OS) were evaluated by univariate and multivariate analyses. Results: Of the 52 patients, 19 (36.5 %) experienced tumor recurrence during the follow-up period and 18 (35.8 %) died. The 3-year RFS and OS were 62.3 and 61.5 %, respectively. Preoperative CA19-9 level, tumor differentiation, presence of lymph node metastasis, SUV_max, and TBR were significant prognostic factors for both RFS and OS (p < 0.05) on univariate analyses, and patient age showed significance only for predicting RFS (p < 0.05). On multivariate analyses, SUV_max and TBR were independent prognostic factors for RFS, and tumor differentiation, SUV_max, and TBR were independent prognostic factors for OS. Conclusion: SUV_max and TBR on preoperative ¹⁸F-FDG PET/CT are independent prognostic factors for predicting RFS and OS in patients with AAC; patients with high SUV_max (>4.80) or TBR (>1.75) had poor survival outcomes. The role of and indications for adjuvant therapy after curative resection of AAC are still unclear. ¹⁸F-FDG uptake in the primary tumor could provide additive prognostic information for the decision-making process regarding adjuvant therapy.