Table 2.
Comparison of IHC, FISH, and Real-Time PCR Analyses of HER-2 in Formalin-Fixed, Paraffin-Embedded Breast Tumors
| Group* | Case no. | Hercep1&2† 0, 1+, 2+, 3+ | FISH HER-2/CEP 17‡ | Ratio mRNA§ HER-2/ β-actin N = 5 | Ratio DNA¶ HER-2/gastrin N = 5 |
|---|---|---|---|---|---|
| A | 1 | 3 | >7.0 | 149.88 [107.55; 179.38] | 23.22 [10.58; 30.48] |
| 2 | 3 | 6.0 | 85.50 [23.01; 130.19] | 19.59 [6.6; 34.25] | |
| 3 | 3 | 3.1 | No result∥ | 2.33 [0.62; 34.44] | |
| 4 | 3 | >7.5 | 182.92 [105.93; 262.1] | 67.45 [41.22; 77.66] | |
| 5 | 3 | 6.0 | 222.12 [183.96; 262.1] | 43.79 [7.3; 94.38] | |
| 6 | 3 | 6.6 | 24.46 [3.52; 43.97] | 17.98 [6.67; 25.63] | |
| 7 | 3 | 4.2 | 29.59 [10.53; 43.67] | 4.12 [1.98; 6.48] | |
| 8 | 3 | 4.0 | 65.86 [33.78; 120.2] | 7.48 [4.73; 11.18] | |
| B | 9 | 2 | 1.1 | 17.06 [9.71; 35.88] | 2.89 [1.8; 3.42] |
| 10 | 2 | 1.1 | 4.82 [3.35; 7.98] | 2.46 [1.51; 2.69] | |
| 11 | 2 | 1.1 | 58.93 [31.39; 98.55] | 2.08 [1.85; 2.38] | |
| 12 | 2 | 1.2 | 6.59 [5.42; 10.05] | 1.88 [1.38; 2.15] | |
| 13 | 2 | 0.9 | 61.61 [42.65; 82.67] | 2.13 [1.44; 2.57] | |
| 14 | 2 | 1.0 | 7.67 [4.52; 11.29] | 1.91 [0.86; 3.01] | |
| 15 | 2 | 1.0 | 4.82 [0.92; 9.69] | 2.6 [1.87; 3.93] | |
| 16 | 2 | 1.0 | 2.85 [1.93; 5.1] | 1.98 [1.24; 2.4] | |
| C | 17 | 1 | 0.8 | 18.05 [8.54; 36.41] | 0.93 [0.67; 1.14] |
| 18 | 1 | 1.1 | 43.85 [34.81; 51.71] | 0.64 [0.03; 1.24] | |
| 19 | 1 | 1.1 | 8.62 [3.46; 19.41] | 0.34 [0.09; 0.93] | |
| 20 | 1 | 0.9 | 26.23 [10.74; 63.1] | 0.37 [0.05; 0.73] | |
| 21 | 1 | 1.1 | 17.45 [10.64; 35.95] | 1.58 [1.26; 1.74] | |
| 22 | 1 | 1.1 | 9.89 [6.38; 13.27] | 1.45 [0.16; 2.57] | |
| 23 | 1 | 1.3 | 13.93 [9.55; 21.75] | 1.12 [0.28; 1.58] | |
| 24 | 1 | 0.9 | 10.61 [6.1; 13.89] | 1.24 [0.54; 3.15] | |
| D | 25 | 0 | 1.0 | 51.53 [7.77; 130.58] | 1.79 [0.86; 2.46] |
| 26 | 0 | 1.0 | 0.46 [0.32; 0.76] | 1.98 [1.19; 2.52] | |
| 27 | 0 | 1.0 | 35.51 [4.25; 104.4] | 1.53 [0.86; 1.9] | |
| E | 28 | 1 | 1.1 | 33.33 [13.99; 41.3] | 0.96 [0.34; 1.47] |
| 29 | 1 | 2.4 | 7.15 [2.95; 10.58] | 2.15 [1.99; 2.33] | |
| 30 | 1 | 1.4 | 29.92 [7.18; 95.76] | 1.86 [0.93; 2.71] |
Groups A–D = Invasive ductal carcinomas (HercepTest 3+, 2+, 1+ positive; 0, negative). Group E = DCIS.
Duplicate blinded HER-2 protein expression assay (HercepTest).
CEP 17 = probe for chromosome 17 centromere region.
Relative HER-2/neu mRNA expression (Her-2/neu/β-actin) in absolute values. Values are given as means, with min and max values.
Relative HER-2/neu gene amplification in accordance with the LightCycler HER2/neu DNA Quantification kit (Roche). Values are given as means, with min and max values.
Insufficient mRNA for analyzing both HER-2 and β-actin.
A–D = Invasive ductal carcinomas.
E = DCIS cases.
Abbreviations: DCIS, ductal carcinoma in situ; IHC, immunohistochemistry; FFPE, formalin-fixed, paraffin-embedded; FISH, fluorescence in situ hybridization.