Table 4. Multivariate analysis of various predictive factors for the presence of four or more node metastases.

Factors	Odds ratio (95% CI)	P -value
Pathological tumour size
⩽2 cm vs > 2cm	2.148 (0.766–6.028)	0.146
Nuclear grade
1+2 vs 3	0.665 (0.168–2.626)	0.561
Oestrogen receptor status
Absent vs present	0.326 (0.075–1.416)	0.135
HER2 status
Negative + unknown vs positive	2.257 (0.722–7.056)	0.162
Lymphovascular invasion
Absent vs present	4.258 (0.888–20.406)	0.07
CK19 mRNA in SLN (copies μl−1)
<1.0 × 105 vs ⩾1.0 × 105	3.662 (1.301–10.305)	0.014

Abbreviations: CI=confidence interval; CK19=cytokeratin 19; SLN=sentinel lymph node.