Table 2. Statistical analyses of correlation between HER2 gene copy number status and efficacy in terms of progression free survival (PFS) and overall survival (OS).
| |
PFS |
OS |
||||
|---|---|---|---|---|---|---|
| N | Median PFS (months) | HR (95% CI; P-value) | N | Median PFS (months) | HR (95% CI; P-value) | |
| All patients |
162 |
6 |
|
153 |
11.3 |
|
|
HER2-all-A vs others (HER2-non A and HER2-minor-A) |
6 vs 156 |
2.5 vs 6.7 |
3.65 (1.57–8.46; P=0.0026) |
6 vs 147 |
4.2 vs 13 |
5.05 (2.17–11.77; P=0.0002) |
|
HER2-FISH+ vs HER2-FISH− |
107 vs 55 |
7.4 vs 3.9 |
2.00 (1.42–2.83; P<0.0001) |
100 vs 53 |
12.7 vs 9.7 |
1.18 (0.83–1.69; P=0.3600) |
|
HER2-all-A vs HER2-FISH− vs HER2-FISH+* |
6 vs 55 vs 101 |
2.5 vs 3.9 vs 7.6 |
|
6 vs 53 vs 94 |
4.2 vs 9.7 vs 13 |
|
|
HER2-all-A vs HER2-FISH− |
|
|
2.28 (0.96–5.40; P=0.0606) |
|
|
4.36 (1.82–10.89; P=0.0010) |
|
HER2-all-A vs HER2-FISH+* |
|
|
4.90 (2.08–11.55; P=0.0003) |
|
|
5.48 (2.33–12.92; P<0.0001) |
| HER2-FISH− vs HER2-FISH+* | 2.15 (1.51–3.05; P<0.0001) | 1.26 (0.87–1.81; P=0.2167) | ||||
Abbreviations: CI=confidence interval; FISH=fluorescent in situ hybridization; HER2-all-A=HER2 gene amplification in all the sample (R:HER2/CEP17⩾2 in ⩾90% of cells); HER2-FISH+HER2 gene copy number gain (CNG: presence of ⩾4 copies of the HER2 gene in ⩾40% of the cells) and HER2-A (HER2 gene amplification as R:HER2/CEP17⩾2 in ⩾10% of cells); HER2-FISH−=absence of CNG and absence of HER2 amplification; HER2-minor-A=HER2 gene amplification in a minor population (10–60% of cells); HER2-non-A: absence of HER2 gene amplification; HR=hazard ratio. Significant P-values are in bold. HR with the corresponding 95% CI and P-values for PFS and OS were calculated using the analysis of the Cox proportional-hazards regression model.