Fig. 2

Univariable analyses with the predictors dichotomized (< 35 vs. ≥35 years, > 20 vs. ≤20 mm, and positive vs. negative lymph nodes; 2a–c) and categorized accordingly: age at diagnosis in three categories (> 50, 35–50, and < 35 years at diagnosis), tumor size in three (T1, T2, and T3), and lymph nodes in four categories (N0, N1–3, N4–9, and N ≥ 10; 2d–f)