Molecular alterations associated with improved survival in pancreatic cancer patients treated with radiation or chemotherapy.

Multiple genetic alterations, several of which may be important prognostic markers, characterize the development of cancer in pancreas. We review our findings from previously published studies with regard to molecular alterations associated with survival differences in patients treated with conventional radiation and chemotherapies used as adjuvant or palliative therapy. K-ras-negative patients with pancreas cancer show improved survival with radiation therapy compared to K-ras-positive patients with pancreas cancer. p53 expression is associated with shorter survival when compared to no p53 expression in pancreas cancer patients treated with radiation therapy or chemotherapy. Pancreas cancer patients whose tumors express p21 show significant survival advantages when treated with chemotherapy or radiation therapy. An inverse relationship is observed with respect to p21 and p53 expression and clinical stage. Although stage and surgical resectability remain the most important variables with respect to pancreas cancer survival, these findings suggest promising opportunities for gene therapies designed to enhance p21 expression or restore wild-type K-ras or p53 function in pancreatic tumors.