Table 3.

Histological assessment of N0 patients with and without cancer recurrence, matched according to demographic and pathological characteristics

	Group 1 (41 N0 patients with recurrence)	Group 2bis (41 N0 patients without recurrence)	P value3
Lymphatic embolization	34	13	0.001
Microvascular infiltration	11	7	0.285
Perineural infiltration	19	6	0.001
p531	49.1% (0-100)	33.8% (0-100)	0.041
Ki671	52.7% (30-80)	33.1% (15-70)	0.038
HER22	7	8	0.785

¹Our immunohistochemical analysis of p53 and Ki67 differ from some of those found in other studies because we expressed them as the number of cancer cells showing immunohistochemical staining over 100 cells, thus as a rate and not as a binomial variable (yes/no). Statistical analysis was retrospectively performed by Student t-test;

²Immunohistochemical detection, both 2+ and 3+ were considered positive;

³P values of χ² test for lymphatic embolization, microvascular infiltration, perineural infiltration, and HER2. P values of Student t-test for p53 and Ki67.