361 Background: To investigate correlation of genetic alterations of pancreatic ductal adenocarcinoma (PDAC) with patients’ survival, recurrence patterns, and treatment for recurrent disease. Methods: We reviewed genetic alterations of major 4 genes (K-ras, DPC4, p53, and c-erbB-2) in 699 patients who underwent surgical resection, and correlated with clinical outcomes. Results: Median survival of all patients was 21.7 months, and 5-year survival rate was 20.4%. Alterational rates of each gene were as follows: K-ras, 48.3%; DPC4, 68.1%; p53, 40.8%; c-erbB-2, 14.0%. Mutation of K-ras and inactivation of DPC4 genes were associated with shorter patients’ survival in univariate analysis. In multivariate analysis, mutation of K-ras gene was independently correlated with patients’ survival (especially, GAT and TGT subtypes). Inactivated DPC4 gene had no independent correlation with overall survival, but it was strongly associated with distant metastasis following pancreatectomy. Survival after recurrence (SAR) was evaluated in subdivided groups according to DPC4 gene function (intact or loss)/recurrence patterns (locoregional or distant)/treatment options (local control or systemic therapy). In these 8 groups, patients in intact/locoregional/local control group showed the longest survival (24.2 months of median SAR), and intact/locoregional/systemic therapy and loss/distant/systemic therapy groups were associated with much shorter survival (9.5 and 9.2 months of median SAR, respectively). Conclusions: Assessment of genetic features of PDAC may assist in deciding targeted surveillance or treatment for primary as well as recurrent PDAC, and further studies for therapeutic strategies according to genetic analyses should be devised.