Table 3.

Detection rates per sentinel lymph node in delayed SLND

	Nodal detection rate (%)					SLNs (median, IQR)
	SPIO	Tc99	Difference	95% CI	p*	SPIO	Tc99	p†
WLE	86.9	82.6	4.3	− 19.0, 27.7	1.000	1 (1, 3)	1 (1, 3)	1.000
OPBCT	90.0	12.5	77.5	58.8, 96.2	< 0.001	1 (1, 2)	0 (0, 1)	< 0.001
Mastectomy	83.3	22.0	61.1	36,2, 86.0	< 0.001	1 (1, 2)	0 (0, 1)	0.021
Total	86.9	32.2	54.5	40.9, 68.2	< 0.001	1 (1, 2)	0 (0, 1)	< 0.001

	Nodal detection rate (%)					SLNs (median, IQR)
	SPIO+BD	Tc99	Difference	95% CI	p*	SPIO+BD	Tc99
WLE	95.7	82.6	13.0	− 9.6, 35.7	0.375	2 (1, 3)	1 (1, 3)	0.250
OPBCT	95.0	32.5	62.5	42.1, 82.9	< 0.001	1 (1, 2)	0 (0, 1)	< 0.001
Mastectomy	94.4	30.6	63.8	42.0, 95.8	< 0.001	1 (1, 2)	0 (0, 1)	0.013
Total	93.9	42.4	51.5	38.5, 64.5	< 0.001	1 (1, 2)	1 (0, 1)	< 0.001

BD blue dye, CI confidence interval, IQR interquartile range, OPBCT oncoplastic breast-conserving therapy, SPIO superparamagnetic iron oxide nanoparticles, Tc⁹⁹ Technetium 99, WLE wide local excision

*p-value is two-sided and refers to McNemar’s test for paired proportions, †p-value is two-sided and refers to Wilcoxon signed-rank test