The overall ORs for KRAS and GNAS mutations in male patients with IPMN were 1.065 (95 % CI 0.680–1.668; P = 0.782, Q = 7.216, I2 = 0.000) and 1.946 (95 % CI 1.156–3.278; P = 0.012, Q = 9.885, I2 = 49.419), respectively (Fig. 3). Here, GNAS is linked to pancreatic intraductal papillary-mucinous neoplasm.