PO-0669: External validation of a survival model for stage III NSCLC: focus on similarities or differences?. (April 2015) - Oberije, C.; Deasy, J.; Lievens, Y.; Belderbos, J.; Vandecasteele, K.; Uyterlinde, W.; Rimner, A.; Troost, E.G.C.; Lambin, P.