Table 2.

Non-sentinel-node involvement rate.

	ALND		NSN = 0		NSN+		Chi2
	n	%	n	%	n	%	P
	840		654	78.3	176	21.1
Age
≤40	48	5.75	41	6.27	7	3.98	0.3241
41–75	739	88.50	578	88.38	156	88.64
>75	48	5.75	35	5.35	13	7.39
Missing data	5		5		0
pT size
≤10	108	12.97	99	15.18	9	5.11	0.0016
10–30	633	75.99	485	74.39	143	81.25
>30	92	11.04	68	10.43	24	13.64
Missing data	7		7		0
Grade
1	180	22.0	151	23.63	27	15.52	0.0691
2	429	52.44	326	51.02	100	57.47
3	209	25.55	162	25.35	47	27.01
Missing data	22		20		2
LVI
No	252	31.46	187	29.92	64	37.43	0.0612
Yes	549	68.54	438	70.08	107	62.57
Missing data	39		34		5
Extracapsular extension
No	619	78.55	503	81.13	111	68.10	0.0003
Yes	169	21.45	117	18.87	52	31.90
Missing data	52		39		13
Endocrine receptors
Negative	82	9.90	66	10.19	16	9.14	0.6829
Positive	746	90.10	582	89.81	159	90.86
Missing data	12		11		1
Her2
Negative	721	88.25	562	87.95	155	89.08	0.6820
Positive	96	11.75	77	12.05	19	10.92
Missing data	23		20		3
Number SN+
≤2	797	97.43	631	98.44	161	93.60	0.0004
>2	21	2.57	10	1.56	11	6.40
Missing data	1		1		0
Status SN
pN0 (i+)	33	4.27	31	5.07	2	1.27	<0.0001
pN1mi	216	27.94	192	31.42	22	13.92
pN1macro	524	67.79	388	63.50	134	84.81
Missing data	67		48		18
AC
No	257		230	35.55	27	15.52	<0.0001
before ALND	150		148	22.87	29	16.67
after ALND	388		269	41.58	118	67.82
Missing data	90		39		9
Surgery
Conservative	682	81.29	538	81.76	142	80.68	0.7427
Mastectomy	157	18.71	120	18.24	34	19.32
Missing data	1		1		0
Radiotherapy
No	30	3.65	29	4.48	1	0.58	0.0151
Yes	793	96.35	618	95.52	172	99.42
Missing data	17		12		2

Bold entries indicate statistical significant differences.