2. Diagnostic Utility of FDG-PET in the Clinical Management of Patients with Suspected Recurrent Pancreatic Carcinoma after Whipple Procedure

Purpose: We evaluated the usefulness of FDG-PET in the assessment of patients with suspected pancreatic carcinoma who have previously undergone a Whipple procedure.

Methods and Materials: Attenuation-corrected FDG-PET was performed in 11 patients (5 males, 6 females, age range 52–76 years), with suspected recurrent pancreatic carcinoma after Whipple procedure. Recurrence was suspected based on clinical, laboratory (CA19-9 serum tumor marker level), or abdominal CT findings. Diagnostic validation was by histology in 2 patients and radiologic or clinical follow-up (5 to 48 months) in 9 patients. Changes in therapeutic management that were prompted by PET were tabulated.

Results: PET was concordant with the findings of abdominal CT in 7 patients (6 true-positive, 1 true-negative). PET detected unsuspected lung lesions in 1 of these patients that was subsequently confirmed by a chest CT. PET was discordant with abdominal CT in 4 patients. PET detected tumor recurrence in 3 of 4 patients in this group (27% of total) who had non-diagnostic CT and elevated CA19-9 serology. Chemotherapy was initiated in 2 of these 3 patients (18% of total), while the other patient died shortly after the PET study from pneumonia and recurrent tumor was confirmed at autopsy. The remaining 1 of 4 patients in the discordant group had a false-positive PET study due to relatively high FDG localization in a displaced loop of bowel.

Conclusion: PET is useful in localizing the tumor in post-Whipple patients with suspected recurrent pancreatic carcinoma and can impact their clinical management.