Clinical impact of carbonic anhydrase 9 expression on neoadjuvant chemoradiotherapy in pancreatic ductal adenocarcinoma.

Background: PDAC cells upregulate carbonic anhydrase 9 (CA9) expression in order to survive in hypoxic tumor environments, which plays a key role in tumor progression. However, the relationship between CA9 expression and preoperative treatment has not been clarified. We evaluated the clinical impact of CA9 expression on the efficacy of neoadjuvant chemoradiotherapy (NACRT) in pancreatic ductal adenocarcinoma (PDAC).