E2F1 and neoplasm: However, the significantly higher positivity rate of e2f-1 expression was respectively observed in the groups of the tumor with ≥ 5 cm (P = 0.001), the ≥ 35% of metastatic lymph nodes ratio (P = 0.013), the deeper invasion of tumor (P = 0.003), the later stages of TNM (P = 0.017) and the ≥ 20 months of average survival time (P = 0.005) in comparison with the lower positivity rate of e2f-1 expression in the groups of the tumor with < 5 cm, the < 35% of metastatic lymph node ratio, the slighter invasion of tumor, the earlier stages of TNM and the < 20 months of average survival time (Table 3).