Table 2: Summary of concordant rates from literature review.

Total cases

Total IHC/FISH positive cases

HER 2 IHC/FISH positive concordance

Total IHC/FISH negative/equivocal cases

HER2 IHC/FISH negative concordance

Overall HER2 concordance

Sughayer et al. 2020 [22]

113

0

ND

113

99.1%

99.1%

Chang et al. 2018 [24]

(separate IHC and FISH results)

30

0

ND

30

100 (IHC)/93.3 (FISH)%

100/93.3%

Neely et al. 2018 [23]

610

5

20%

558

100%

98.6%

Park et al. 2014 [25] (FISH only)

265

2

0%

245

100%

99.2%

Dvorak et al. 2013 [26] (FISH only)

194

8

50%

186

100%

96%

Dabbs et al. 2011 [27]

843

36

42%

784

99%

98%

IHC: Immunohistochemistry; ODX: Oncotype DX; RT-PCR: Reverse Transcription-Polymerase Chain Reaction; IHC+: Positive by IHC stain; IHC-: Negative by IHC stain; FISH: Fluorescence In Situ Hybridization; HER2: Human Epidermal Growth Factor Receptor 2; ND: No Data.