The prognosis of pancreatic adenocarcinoma remains poor, with a 5-year survival rate lower than 5%. Resection, the gold standard treatment, can be performed in less than 10% of patients. Following surgery, the median survival is 12 months for the most favorable cancer patients. Concomitant chemoradiation, as an adjuvant treatment is superior to surgery alone, in terms of survival; controlled trials are currently performed. Neoadjuvant chemoradiation is a new approach, potentially able to increase survival and resection rate. This work justifies the role of these schemes, in terms of modalities and potential advantages. A second part is dedicated to gastric carcinoma, with a review of the current results of chemoradiation, whose efficiency, even though a trend can be observed, remains to be proven. Prospective adjuvant combined treatments are ongoing, in France and in the States.