Preoperative serum HER2 extracellular domain levels in primary invasive breast cancer

BMC Cancer

Table 3 Prediction performance of tissue HER2 status and concordance with serum HER2 ECD level

Group analyzed^a	Cross-table		P ^b	Concordance rate	Prediction performance
				Concordance rate	Sensitivity	Specificity	PPV	NPP
(1) Total patients (n = 2,860)			<0.001	78.7	15.0	99.0	82.5	78.5
	Tissue(+)^e	Tissue(-)^f
Elevated^c	104	22
Normal^d	588	2,146
(2) Total patients (n = 2,860) HER2 ECD cutoff = 10.2 ng/ml			<0.001	70.4	54.9	75.3	41.5	84.0
	Tissue(+)	Tissue(-)
Elevated	380	535
Normal	312	1,633
(3) Negative lymph node status (n = 1,747)			<0.001	80.3	11.2	99.1	76.4	80.4
	Tissue(+)	Tissue(-)
Elevated	42	13
Normal	332	1,360
(4) Positive lymph node status (n = 1,113)			<0.001	76.2	19.5	98.9	87.3	75.4
	Tissue(+)	Tissue(-)
Elevated	62	9
Normal	256	786
(5) Stage I (n = 1,243)			<0.001	80.4	9.6	99.2	75.8	80.5
	Tissue(+)	Tissue(-)
Elevated	25	8
Normal	236	974
(6) Stage II (n = 1,212)			<0.001	78.7	13.3	98.9	79.2	78.7
	Tissue(+)	Tissue(-)
Elevated	38	10
Normal	248	916
(7) Stage III (n = 405)			<0.001	73.3	28.3	98.5	91.1	71.1
	Tissue(+)	Tissue(-)
Elevated	41	4
Normal	104	256

^aA diagnostic cutoff value of 15.2 ng/ml was used except where stated otherwise.
^bCalculated by chi-square test.
^cElevated serum HER2 ECD level.
^dNormal serum HER2 ECD level.
^eDefined as 3+ on IHC or amplification on fluorescence in situ hybridization in cases of IHC 2+.
^fTissue HER2 negative.
PPV positive predictive value, NPV negative predictive value.

ISSN: 1471-2407