219 Routine Imaging Versus Watchful Waiting in the Follow-Up of Resected Pancreatic Adenocarcinoma: A Single-Centre Retrospective Cohort Study

Abstract Aim To compare survival and recurrence-related outcomes in patients undergoing routine imaging versus a watchful waiting strategy following surgical resection of pancreatic ductal adenocarcinoma (PDAC). Method This retrospective cohort study included patients who underwent PDAC resection at a UK tertiary centre between January 2017 and December 2022. Patients were categorised based on follow-up strategy: routine imaging (scheduled CT every 6 months for the first 2 years post-operatively, then annually thereafter) or watchful waiting (annual clinical review with imaging triggered by symptoms or biomarkers). Primary outcomes were overall survival (OS), disease-free interval (DFI), and post-recurrence survival (PRS), calculated through Kaplan-Meier analysis and compared using the log-rank test. Secondary outcomes included recurrence characteristics and the receipt of palliative chemotherapy. Multivariable Cox and logistic regression models adjusted for covariates. Results 83 patients were included; 66 (80%) developed PDAC recurrence. No significant differences were observed between groups in OS (median 30.3 months [routine imaging] vs. 27.3 months [watchful waiting], p=0.47), DFI (21.0 vs. 19.7 months, p=0.90), or PRS (7.6 vs. 5.5 months, p=0.46). These findings remained non-significant after adjustment for demographic, clinical and pathological covariates. Palliative chemotherapy was more frequently given in the routine imaging group (56% vs. 35%), but this difference was non-significant (p=0.15). Recurrence patterns were similar between groups. Conclusions Routine imaging was not demonstrated to improve survival or recurrence-related outcomes compared to watchful waiting after PDAC resection. Further studies are needed to define optimal follow-up strategies balancing early detection, patient outcomes, and resource allocation.