Precise stratification of prognosis in pancreatic ductal adenocarcinoma patients based on pre- and postoperative genomic information.

Background: Pancreatic ductal adenocarcinoma (PDAC) has the highest mortality rate among all cancers; hence, multidisciplinary treatment is essential for patients with PDAC. Although the resectability status, tumour marker, KRAS circulating tumour DNA (mutKRAS-ctDNA) mutations, and GATA binding 6 (GATA6) expression status are promising prognostic biomarkers, their effective integration before and after surgery remains unclear.

Methods: In this retrospective cohort study, patients with PDAC who had undergone radical resection were enrolled, and pre- and postoperative independent factors associated with poor prognosis were identified using Cox hazard modelling. Risk stratification systems were developed using the identified prognostic factors and investigated for the ability to predict prognosis.

Results: A total of 91 patients with PDAC were included (median follow-up duration, 28 months). Borderline resectable or locally advanced cancer at diagnosis, elevated carbohydrate antigen 19-9 (CA19-9) level, and mutKRAS-ctDNA-positive status were identified as independent preoperative factors associated with poor prognosis. The postoperative factors significantly associated with shorter overall survival were low GATA6 expression, elevated CA19-9 level, and mutKRAS-ctDNA-positive status. Finally, the preoperative and postoperative risk scoring systems developed using Cox modelling hazard ratio values could significantly stratify prognosis after curative resection for PDAC.

Conclusion: A risk stratification system based on liquid biopsy, specialised for each phase (pre- and post-surgery), has been proven to be a useful, simple, and practical prognostic prediction clinical tool to determine the optimal multidisciplinary treatment protocol for PDAC.