18-Fluorodeoxyglucose Positron Emission Tomography Predicts Recurrence in Resected Pancreatic Ductal Adenocarcinoma.

BACKGROUND

We aimed to determine whether treatment should be stratified according to 18-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) maximum standardized uptake values (SUV) in pancreatic ductal adenocarcinoma.

METHODS

Patients who underwent preoperative 18F-FDG PET/CT between 2006 and 2014 (n = 138) were stratified into high (≥ 4.85) and low (< 4.85) PET groups. The clinicopathological characteristics and prognostic outcomes were analyzed retrospectively.

RESULTS

The primary tumor SUV was positively correlated with preoperative CA19-9 levels (P < 0.001). The high PET group failed to achieve postoperative CA19-9 normalization (P = 0.014). Disease-specific (P < 0.001), recurrence-free (P < 0.001), liver recurrence-free (P < 0.001), and peritoneal recurrence-free (P = 0.020) survivals were significantly shorter in the high PET group. The primary tumor SUV was an independent predictive risk factor for liver metastasis (hazard ratio 3.46, 95% confidence interval 1.61-7.87; P = 0.001) and peritoneal recurrence (hazard ratio 3.36, 95% confidence interval 1.18-10.89; P = 0.023).

CONCLUSIONS

Surgical resection failed to achieve CA19-9 normalization in the high PET group and distant recurrence was frequent. This suggests the potential for residual cancer at distant sites, even after curative resection. Stronger preoperative systemic chemotherapy is preferred for the high PET group patients.