Table 3.

The correlation between human epidermal growth factor receptor 2 digital image analysis scores and fluorescence in situ hybridization results in 442 cases with fluorescence in situ hybridization

	Visiopharm(%)
	Negative (0/1+)	Equivocal (2+)	Positive (3+)	Total
FISH positive
Group1	3(0.9)	6(9)	53(91.4)	62
Group3	0(0)	1(1.5)	3(4.5)	4
FISH negative
Group2	1(0.3)	0(0)	0(0)	1
Group4	36(11.4)	24(35.8)	2(3.0)	62
Group5	277(87.4)	36(53.7)	0	313
Total	317	67	58	442

HER2 FISH results were categorized into the following 5 groups according to ASCO/CAP HER2 guidelines: Group 1: HER2/CEP17 ratio ≥2.0 and average HER2 copy number ≥4.0 signals/cell; Group 2 HER2/CEP17 ratio ≥2.0 and average HER2 copy number <4.0 signals/cell; Group 3: HER2/CEP17 ratio <2.0 and average HER2 copy number ≥6.0 signals/cell; Group 4: HER2/CEP17 ratio <2.0 and average HER2 copy number ≥4.0 and <6.0 signals/cell; Group 5: HER2/CEP17 ratio <2 and average HER2 copy number <4.0 signals/cell. HER2: Human epidermal growth factor receptor 2, FISH: Fluorescence in situ hybridization, ASCO: American Society of Clinical Oncology, CAP: College of American Pathologist