The DPC4/SMAD4 genetic status determines recurrence patterns and treatment outcomes in resected pancreatic ductal adenocarcinoma: A prospective cohort study

OBJECTIVES: The objective of this study was to investigate the role of genetic status of DPC4 in recurrence patterns of resected pancreatic ductal adenocarcinoma (PDAC). METHODS: Between April 2004 and December 2011, data on patients undergoing surgical resection for PDAC were reviewed. Genetic status of DPC4 was determined and correlated to recurrence patterns and clinical outcomes. RESULTS: Analysis of 641 patients revealed that genetic status of DPC4 was associated with overall survival and was highly correlated with recurrence patterns, as inactivation of the DPC4 gene was the strongest predictor of metastatic recurrence (odds ratio = 4.28). Treatment modalities for recurrent PDAC included chemotherapy alone and concurrent chemotherapy along with local control. For both locoregional and metastatic recurrence, local control resulted in improved survival; however, for groups subdivided according to recurrence patterns and genetic status of DPC4, local control contributed to improved survival in locoregional recurrences of patients with expressed DPC4, while chemotherapy alone was sufficient for others. CONCLUSIONS: Genetic status of DPC4 contributes to the recurrence patterns following pancreatectomy, and patients with an initially expressed DPC4 gene receive a greater benefit from intensive local control for locoregional recurrence. The DPC4 gene, therefore, may aid the establishment of treatment strategies for initial adjuvant treatment or for recurrent PDAC.