Fig. 2.

Stage migration between the 7th and 8th editions of AJCC/UICC staging system as well as the modified pTNM staging system for both the training and external validation cohorts. a Classification illustrated in the training cohort; b classification illustrated in the external validation cohort; c patient grouping in the training cohort; d patient grouping in the external validation cohort. Stage migration was mainly observed for patients with stage III disease; therefore, for better contrast among patients at this specific stage, its sub-stages IIIA, IIIB, and IIIC were colored green, blue, and red, respectively. Abbreviations: AJCC/UICC, American Joint Committee on Cancer/Union for International Cancer Control; ed., edition of the tumor-node-metastasis (TNM) staging system