Table 3. Multivariable stepwise logistic regression analyses of clinico-factors associated with SNB positivity, RFS and OS.

Analysis	Factor	Factor groups	OR (95% CI) for SNB positivity HR (95% CI) for RFS/OS	P-value
SNB positivitya	Breslow thickness (mm)	0.75–1	1.0
		1.01–2	1.6 (0.7–3.5)	0.3
		2.01–4	2.9 (1.3–6.9)	0.01
		>4	3.4 (1.3–9.3)	0.02
	Mitotic count (mm−2)	0	1.0
		0.1–6	2.7 (1.5–5.1)	0.002
		>6	4.2 (2.0–8.7)	<0.0001
	Tumour site	Arm	1.0
		Head/neck	1.9 (0.7–4.7)	0.2
		Leg	2.4 (1.3–4.3)	0.005
		Trunk	2.6 (1.4–4.8)	0.002
RFSb	SNB status	Negative	1.0
		Positive	2.5 (1.5–4.3)	0.001
	Breslow thickness (mm)	0.75–1	1.0
		1.01–2	2.2 (0.6–7.2)	0.2
		2.01–4	2.2 (0.6–7.4)	0.2
		>4	5.3 (1.5–18.2)	0.009
	Ulceration	Absent	1.0
		Present	1.6 (1.0–2.5)	0.03
	Vessel invasion	Absent	1.0
		Present	3.0 (1.4–6.3)	0.003
	Tumour site	Arms	1.0
		Legs	5.0 (2.0–12.5)	0.001
		Head and neck	1.5 (0.7–3.3)	0.3
		Trunk	2.5 (1.2–5.2)	0.02
OSc	SNB status	Negative	1.0
		Positive	4.6 (1.9–10.8)	0.001
	Breslow thickness (mm)	0.75–1	1.0
		1.01–2	1.5 (0.3–6.5)	0.6
		2.01–4	1.7 (0.4–7.4)	0.5
		>4	4.8 (1.1–21.1)	0.04

Abbreviations: CI=confidence interval; HR=hazards ratio; OR=odds ratio; OS=overall survival; RFS=relapse-free survival; SNB=sentinel node biopsy; TIL=tumour-infiltrating lymphocyte.

^aIncluded 408 patients in analysis,

^bIncluded 412 patients in analysis,

^cIncluded 409 patients in analysis.