Retrospective Study of Selective Submandibular Neck Dissection versus Radical Neck Dissection for N0 or N1 Necks in Level I Patients with Oral Squamous Cell Carcinoma

Table 3

Cox’s proportional hazard model with univariate and multivariate analysis in clinically N0 necks.

	Regional control						Disease-specific survival
	Univariate			Multivariate			Univariate			Multivariate
	Hazard ratio (95% CI)	P value		Hazard ratio (95% CI)	P value		Hazard ratio (95% CI)	P value		Hazard ratio (95% CI)	P value
Type of neck dissection MRND/SMND	1.061 (0.381–2.935)	0.913					0.986 (0.337–2.886)	0.980
Clinical tumor stage T3, 4/T1, 2	1.896 (0.742–2.885)	0.204					3.048 (1.105–8.043)	0.031		14.949 (8.643–21.352)	0.002
Primary tumor site Tongue	1.113 (0.412–2.080)	0.857					1.219 (0.539–3.052)	0.794
Tumor depth (Tongue) ≧4 mm	1.687 (0.659–4.260)	0.465					2.386 (0.935–4.777)	0.061
Poorly or Moderately differentiated	1.061 (0.403–2.446)	0.913					1.490 (0.530–4.187)	0.449
Mode of invasion Grade 4	2.074 (0.815–4.243)	0.148					1.975 (0.871–4.130)	0.350
Neoadjuvant chemoradiotherapy	0.277 (0.107–0.825)	0.045		0.136 (0.050–0.469)	0.049		0.269 (0.076–0.953)	0.042		0.412 (0.150–0.924)	0.032
Pathological nodal stage pN(+)	5.101 (2.470–10.172)	0.003		3.542 (1.447–7.122)	0.027		4.081 (1.299–12.816)	0.016		6.541 (2.463–9.257)	0.014
Extracapsular spread	5.095 (1.383–18.461)	0.031		31.333 (13.443–75.119)	0.005		5.487 (2.238–14.315)	0.025		15.915 (11.440–27.967)	0.024
Adjuvant chemoradiotherapy	2.589 (0.643–8.849)	0.137					2.806 (0.792–9.942)	0.110

SMND: selective submandibular neck dissection; MRND: modified radical neck dissection; CI: confidence interval.