Blood Type as a Predictor of High-Grade Dysplasia and Associated Malignancy in Patients with Intraductal Papillary Mucinous Neoplasms

Intraductal papillary mucinous neoplasms (IPMNs) are precursor lesions to the development of pancreatic adenocarcinoma. We determined if non-O blood groups are more common in patients with IPMN and if blood group is a risk factor for progression to invasive pancreatic cancer among patients with IPMN.

The medical records were reviewed of all patients undergoing resection of an IPMN at Johns Hopkins Hospital from June 1997 to August 2016. Potential risk factors of high-grade dysplasia and associated adenocarcinoma were identified through a multivariate logistic regression model.

Seven hundred and seventy-seven patients underwent surgical resection of an IPMN in which preoperative blood type was known. Sixty-two percent of IPMN patients had non-O blood groups (vs. 57% in two large US reference cohorts, P = 0.002). The association between non-O blood group was significant for patients with IPMN with low- or intermediate-grade dysplasia (P < 0.001), not for those with high-grade dysplasia (P = 0.68). Low- and intermediate-grade IPMNs were more likely to have non-type O blood compared to those with high-grade IPMN and/or associated invasive adenocarcinoma (P = 0.045). Blood type O was an independent predictor of having high-grade dysplasia without associated adenocarcinoma (P = 0.02), but not having associated invasive cancer (P = 0.72). The main risk factor for progression to invasive cancer after surgical resection was IPMN with high-grade dysplasia (P = 0.002).

IPMN patients are more likely to have non-O blood groups than controls, but type O blood group carriers had higher odds of having high-grade dysplasia in their IPMN. These results indicate blood group status may have different effects on the risk and progression of IPMNs.