Table 2 Comparison of descriptive characteristics of the two validation groups of the MSKCC model for predicting ALN metastasis, New York and Wei Fang.

Variable	Wei Fang retrospective group			MSKCC, New York validation group
	No.	ALN ( +)		No.	SLN ( +)
	No.	No.	%	No.	No.	%
No. of patients	613	296	48.3	1545	579	37.5
Age (years)
≤ 40	70	42	60.0	181	88	48.6
41–69	473	233	49.3	1066	406	38.1
≥ 70	70	21	30.0	298	85	28.5
Tumor size (cm)
T1mic	1	0	0	51	11	21.6
T1a	15	5	33.3	199	31	15.6
T1b	42	7	16.7	362	84	23.2
T1c	226	78	34.5	624	263	42.1
T2 ≤ 3	179	94	52.5	215	121	56.3
T2 > 3	125	90	72.0	80	56	70.0
T3	25	22	88.0	14	13	92.9
Tumor location
UOQ	301	164	54.5	879	330	37.5
LOQ	80	36	45.0	211	91	43.1
UIQ	130	43	33.1	264	74	28.0
LIQ	33	17	51.5	135	49	36.3
Central	69	36	52.2	56	35	62.5
Histologic grade*
I	15	1	6.7	97	11	11.3
II	449	210	46.8	375	139	37.1
III	125	75	60.0	810	346	42.7
Unknown	-	-	-	97	22	22.7
Tumor type
Ductal	551	276	50.1	1339	514	38.4
Lobular	23	10	43.5	166	61	36.7
Special Type	39	10	25.6	40	4	10.0
LVI
No	366	105	28.7	1205	344	28.5
Yes	247	191	77.3	340	235	69.1
Multifocality
No	510	238	46.7	1155	403	34.9
Yes	103	58	56.3	390	176	45.1
ER
Negative	182	92	50.5	273	99	36.3
Positive	431	204	47.3	1186	462	39.0
Unknown	-	-	-	86	18	20.9
PR
Negative	302	156	51.7	600	219	36.5
Positive	311	140	45.0	858	342	39.9
Unknown	-	-	-	86	18	20.9

Note: Tumor size was defined as the size of the invasive component, and the T classification was carried out according to the 2002 TNM classification system. In cases of multifocal tumors or unifocal tumors that involved more than 1 quadrant, the tumor location was classified in the following order of priority: UOQ, central quadrant (central), LOQ, LIQ, and UIQ. For example, a tumor in the UIQ and central quadrants would be classified as central. A tumor involving the central quadrant and UOQ would be classified as UOQ. If all quadrants were involved, the tumor was classified as UOQ. Positivity of estrogen and progesterone receptors was defined as at least 10% or more immunostained cells.
Abbreviations: UOQ, upper outer quadrant; LOQ, lower outer quadrant; UIQ, upper inner quadrant; LIQ, lower inner quadrant; LVI, lymphovascular invasion; ER, estrogen receptor; PR, progesterone receptor.
*Excluding lobular carcinomas.

Search