Impact of Metastatic Pattern on Survival Following Pancreatectomy for Cancer.

Background and methods: The incidence of pancreatic cancer is increasing, and up to 55% of patients present with metastatic disease at the time of diagnosis. Many patients also develop metastatic disease following surgical resection. The impact of metastatic patterns on outcomes has not been described. A retrospective chart review was conducted of patients with pancreatic adenocarcinoma treated at a tertiary care center from 2012 to 2023. Patients who presented with metastatic disease or developed metastatic disease during their treatment course were identified. Univariate analysis was performed to identify factors associated with specific metastatic patterns. Kaplan-Meier survival curves were estimated for metastatic sites and stratified by treatment.

Results: Of the 330 patients identified, 192 (58.2%) presented with locoregional disease and underwent curative intent surgery before developing metastases, and 138 (41.8%) presented initially with metastatic disease. Median overall survival (OS) with metastases for all patients was 6 months. For patients who underwent curative intent surgery, OS was significantly worse for those who developed peritoneal metastasis compared to patients who developed other sites of metastases (median OS 5.4 vs. 9.2 months, p = 0.0005).

Conclusion: The development of peritoneal metastases after surgery for pancreatic cancer is associated with worse OS compared to other sites of metastatic disease.