Does 18-fluorodeoxyglucose (FDG) uptake by positron emission tomography/computed tomography (PET/CT) predict survival in advanced pancreatic cancer? A single-institution experience.

Abstract

351 Background: Pancreatic cancer is associated with a poor prognosis. Histological grade, stage and serum tumor markers are well established prognostic factors for survival. Some studies suggest that 18-fluorodeoxyglucose (FDG) uptake by positron emission tomography/computed tomography (PET/CT) correlates with survival in pancreatic cancer. In this study, we aimed to determine whether standardized uptake value (SUV), a measure of FDG uptake by fusion PET/CT, had prognostic significance in patients with advanced pancreatic cancer. Methods: Using a comprehensive pancreatic cancer database at H. Lee Moffitt Cancer Center, we identified patients who underwent PET/CT scan as initial workup for resection but were found to have advanced disease (stages III and IV) when surgery was attempted. Data from January 2006 to December 2010 was retrospectively analyzed and correlated with the maximum SUV determined by PET/CT. Other prognostic factors including stage, age, gender, serum tumor marker CA 19-9 levels and the use of chemotherapy were also evaluated using multivariate analysis. Results: We identified 41 consecutive patients who were deemed resectable by virtue of staging workup with CT, PET/CT and endoscopic ultrasound (EUS), but found to have locally advanced/metastatic disease intra-operatively. At the time of analysis, there were a total of 30 deaths. Twelve patients had metastatic disease and 29 had stage III pancreatic cancer. SUV uptake ranged from 2.9 to 16.2 with a mean of 6.4. Median overall survival for the 28 patients with SUV less than or equal to the mean (≤ 6.4) was 14 months (95% confidence interval 10 – 25 months) vs. 9.1 months for the 13 patients with SUV > 6.4 (95% confidence interval 4-17 months). This difference was not statistically significant (p=0.178). On multivariate analysis, use of chemotherapy was the only independent predictor of survival. Conclusions: Glucose uptake by PET/CT, reflected by SUV, was not found to be a predictor of survival in patients with advanced pancreatic cancer. The retrospective nature and limited sample size are limitations of our study, however further research is warranted.