Contrast-enhanced 18F-FDG PET/CT: 1-stop-shop imaging for assessing the resectability of pancreatic cancer.

Abstract

Patients with pancreatic cancer continue to have a poor prognosis, with a 5-y survival rate of less than 5%. Surgery is the only treatment that offers a potential cure. Determining resectability is the principal goal of staging in pancreatic cancer patients. Our objective was to evaluate the value of combined contrast-enhanced (18)F-FDG PET/CT in assessing the resectability of pancreatic cancer and to compare enhanced PET/CT with the performance of PET alone and unenhanced PET/CT. Fifty patients (25 women and 25 men; mean age, 64.3 y; range, 39-84 y) with biopsy-proven pancreatic adenocarcinoma underwent enhanced (18)F-FDG PET/CT for the evaluation of resectability. Criteria for unresectability were distant metastases, peritoneal carcinomatosis, arterial infiltration, or invasion of neighboring organs other than the duodenum. The performance of enhanced PET/CT regarding resectability was compared with that of PET alone and unenhanced PET/CT. Histology, intraoperative findings, and follow-up CT with clinical investigations were used as the reference standard. According to the reference standard, 27 patients had disease that was not resectable because of distant metastases (n=17), peritoneal carcinomatosis (n=5), or local infiltration (n=5). In the assessment of resectability, PET alone had a sensitivity of 100%, specificity of 44%, accuracy of 70%, positive predictive value of 61%, and negative predictive value of 100%; unenhanced PET/CT had respective values of 100%, 56%, 76%, 66%, and 100%; and enhanced PET/CT, 96%, 82%, 88%, 82%, and 96%. In 5 patients, unresectability was missed by all imaging methods and was diagnosed intraoperatively. Enhanced PET/CT was significantly superior to PET alone (P=0.035), and there was a trend for enhanced PET/CT to be superior to unenhanced PET/CT (P=0.070). The use of enhanced PET/CT as a 1-stop-shop imaging protocol for assessing the resectability of pancreatic cancer is feasible and accurate. Enhanced PET/CT is significantly superior to PET alone.