Table 4.
Preplanned multivariate Cox regression analysis of overall survival by extent of disease, primary tumor site, measurability of disease, ECOG status, chemotherapy regimen, and other prespecified covariates: sex, age, number of lesions, number of metastatic sites, type of gastric cancer, visceral metastasis, prior gastrectomy, prior chemotherapy, HER2 status, and region of origin
| Hazard ratio (95% CI) | P value | ||
|---|---|---|---|
| Trastuzumab plus XP versus XP | 0.68 | (0.36–1.27) | 0.2251 |
| Sex (male vs. female) | 0.16 | (0.07–0.41) | <0.0001 |
| Age (<60 vs. ≥60) | 1.07 | (0.54–2.13) | 0.8382 |
| Extent of disease (locally advanced vs. metastatic) | 0.00 | (0.00–.) | 0.9902 |
| Primary tumor site (stomach vs. gastroesophageal junction) | 0.68 | (0.25–1.87) | 0.4559 |
| Measurability of disease (measurable vs. nonmeasurable) | 0.95 | (0.29–3.05) | 0.9268 |
| ECOG performance status | – | – | – |
| Chemotherapy regimen | – | – | – |
| Number of lesions (1–4 vs. >4) | 0.49 | (0.22–1.09) | 0.0818 |
| Number of metastatic sites (1–2 vs. >2) | 0.79 | (0.41–1.50) | 0.4695 |
| Type of gastric cancer | |||
| Diffuse type versus intestinal type | 3.24 | (1.08–9.70) | 0.0356 |
| Mixed type versus intestinal type | 0.91 | (0.30–2.71) | 0.8644 |
| Visceral metastasis (yes vs. no) | 1.15 | (0.48–2.74) | 0.7510 |
| Prior gastrectomy (yes vs. no) | 0.22 | (0.06–0.75) | 0.0159 |
| Prior chemotherapy (yes vs. no) | 27.72 | (1.11–694.38) | 0.0432 |
| HER2 status | |||
| IHC 0/FISH-positive versus IHC 3+/FISH-positive | 5.31 | (1.29–21.86) | 0.0208 |
| IHC 1+/FISH-positive versus IHC 3+/FISH-positive | 4.87 | (1.73–13.70) | 0.0027 |
| IHC 2+/FISH-positive versus IHC 3+/FISH-positive | 1.53 | (0.73–3.18) | 0.2578 |
| IHC 3+/FISH-negative versus IHC 3+/FISH-positive | 25.66 | (1.72–382.49) | 0.0186 |
| Region of origin | – | – | – |
Among 15 prespecified factors, chemotherapy regimen, performance status, and region of origin were not calculated in this table because all Japanese patients received capecitabine as the chemotherapy partner of cisplatin, had Karnofsky performance status of 0–1, and were from Asia (Japan)
CI confidence interval, ECOG Eastern Cooperative Oncology Group, FISH fluorescence in situ hybridization, HER2 human epidermal growth factor receptor 2, IHC immunohistochemistry, XP capecitabine plus cisplatin