The pooled OR from 13 studies including 358 pancreatic cancer patients and 201 normal individuals is shown in Fig. 3 (OR = 17.19, 95% CI = 8.72–33.86, P < 0.00001), indicating that CDKN2A inactivation through methylation plays an important role in the pathogenesis of pancreatic cancer. This evidence concerns the gene CDKN2A and familial pancreatic carcinoma.