Fig. 3

The impact of adjuvant radiotherapy on DFS across different subgroups, as assessed by Log-Rank test with Kaplan-Meier curves. (A) AJCC Stage I-II and NPS 0, (B) AJCC Stage I-II and NPS 1–2, (C) AJCC Stage I-II and NPS 3–4, (D) AJCC Stage III-IVb and NPS 0, (E) AJCC Stage III-IVb and NPS 1–2, (F) AJCC Stage III-IVb and NPS 3–4. Abbreviations AJCC, American Joint Committee on Cancer; DFS, disease-free survival; NPS, Naples prognostic score