Tumor Relapse after Pancreatic Cancer Resection is Detected Earlier by 18-FDG PET than by CT

Pancreatic cancer recurrence is often difficult to detect by conventional imaging. Our aim was to evaluate the impact of fluorodeoxyglucose-positron emission tomography (FDG-PET) in the diagnosis of recurrent pancreatic cancer. One-hundred thirty-eight patients were followed after resection for pancreatic cancer. Sixty-six underwent only CT and were excluded. Seventy-two patients also had FDG-PET. Recurrent patients were divided in two groups: group-1, CT positive and group 2, CT non diagnostic, FDG-PET positive. Characteristics and survival curves of the two groups were compared. Significance was set at p < 0.05. Overall, tumors recurred in 63 of 72 (87.5%) patients; two patients had a second cancer resected, thanks to FDG-PET. Tumor relapse was detected by CT in 35 patients and by FDG-PET in 61. Prognostic factors were similar in groups 1 and 2. Five out of 35 group 1 patients underwent surgery (two R0, two bypass, and one exploratory). Ten out of 28 group 2 patients underwent surgery (four R0, two R2, two bypass, and two exploratory). FDG-PET influenced treatment strategies in 32 of 72 patients (44.4%). Group 2 patients survived longer (P = 0.09), but the difference was not significant. Disease-free survival was similar in groups 1 and 2. Tumor relapse is detected earlier by FDG-PET than by CT. FDG-PET can help select the best candidates for surgical exploration, although the real benefit is still to be defined. It influences treatment strategies in a significant percentage of patients. An earlier diagnosis did not influence survival due to the lack of effective therapies.