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BACKGROUND: Sequential followup imaging is often performed after pancreatic resection for cancer. We attempted to quantify the volume and cost of complex abdominal imaging after pancreatic resection nationwide, and determine whether their frequent use confers benefit. METHODS: Patients with pancreatic adenocarcinoma who underwent surgical resection were identified in SEER-Medicare (1991-2005). Claims for abdominal imaging (CT/CTA, MRI/MRA, PET) ≤5 years after resection were analyzed. After initial screen, CT/CTA was used for longitudinal analyses. Univariate and multivariate analyses were performed by Kruskal-Wallis, logistic regression, and Cox. CT utilization was calculated by dividing total scans by months of available postoperative data. Routine annual CT scanning was defined as at least one CT/CTA performed within each 12-month block, excluding year of death/censoring. To assess frequency of annual CT scanning in patients with superior survival, the top decile were further analyzed. RESULTS: Within 5 years of pancreatic resection, 39316 studies were performed on 2792 patients. The majority of these were CT scans (36521, 92.9%), and the remainder MRI (2425, 6.2%) and PET (370, 0.9%). A minority received no imaging after resection, both when analyzing all patients (168/2792, 6.0%), as well as the subset with >5 year-survival (11/265, 4.2%). Mean monthly CT utilization per patient increased from 0.4 in 1991 to 1.1 in 2005 (p<0.0001), including the immediate postoperative period. Overall mean utilization was 0.6 CT scans per month, but only 0.2 scans per month for patients in the top survival decile. Among all patients, scans were not evenly distributed over the years of the study: many of the scans were clustered. Patients received a mean of 2.8 scans within 3 months of surgery, 4.7 scans between 3 months and 1 year, and 5.6 scans between 1 year and study termination. Among 1127 patients with sufficient survival to allow for analysis, 569 (50.5%) received annual CT scans as previously defined. Interestingly, only 81 (28.9%) of the top-performing patients received annual CT scans. Among all patients, postoperative complications, non-white race, advanced stage, and receipt of chemotherapy or radiation were predictive of receiving routine annual CT scans (p<0.05). Routine annual CT scans were associated with negative rather than positive impact on survival (HR for death 1.2, p=0.02). Based on current Medicare line-item payments, the bare minimum mean imaging cost incurred per patient would be $3736, or $5287 over 5 years of survival. CONCLUSIONS: Most patients undergo abdominal imaging, usually CT, after pancreatic cancer resection. CT utilization has increased in recent years. Administrative data from a large national database suggests that performance of routine annual CT scans after resection does not confer a survival benefit.