Table 4. Progression-free survival analysis.
| Variable | Univariate Analysis | Stage-Adjusted Analysis | ||
| HR (95% CI) | P valuea | HR (95% CI) | P valueb | |
| Age at diagnosis (per year increase) | 1.02 (0.99–1.04) | 0.057 | 1.01 (0.99–1.04) | 0.287 |
| Ethnic group (Malays vs Chinese) | 0.43 (0.15–1.21) | 0.167 | 0.70 (0.24–2.06) | 0.731 |
| Ethnic group (Indians vs Chinese) | 0.37 (0.05–2.70) | 0.37 (0.05–2.76) | ||
| Ethnic group (Others vs Chinese) | 0.00 (NE) | 0.00 (NE) | ||
| Smoking history (Ever-smoker vs non-smoker) | 2.09 (0.66–6.58) | 0.199 | 0.81 (0.16–4.04) | 0.797 |
| Family history of cancer (Positive vs Negative) | 2.22 (0.72–6.86) | 0.154 | 2.91 (0.75–11.26) | 0.121 |
| Presence of comorbidities (Yes vs No) | 1.19 (0.61–2.34) | 0.605 | 0.91 (0.44–1.87) | 0.799 |
| Stage at diagnosis (II vs I) | 3.88 (1.30–11.52) | <0.001 | - | - |
| Stage at diagnosis (III vs I) | 10.45 (4.80–22.71) | - | ||
| Stage at diagnosis (IV vs I) | 16.43 (4.54–59.51) | - | ||
| Tumour differentiation/grade (moderate vs well) | 1.24 (0.54–2.88) | 0.001 | 1.20 (0.52–2.78) | 0.224 |
| Tumour differentiation/grade (poor vs well) | 4.33 (1.86–10.07) | 2.25 (0.89–5.67) | ||
| Tumour type (Non-borderline vs mixed borderline) | 1.91 (0.95–3.84) | 0.065 | 1.33 (0.63–2.80) | 0.447 |
| Ovarian surface involvement (Yes vs No) | 8.86 (3.82–20.53) | <0.001 | 5.26 (2.04–13.58) | 0.001 |
| Lymphovascular invasion (Yes vs No) | 8.13 (3.59–18.42) | <0.001 | 4.60 (1.81–11.71) | 0.001 |
| CA125 (per U/mL increase) | 1.00 (1.00–1.00) | 0.617 | 1.00 (1.00–1.00) | 0.803 |
| Received chemotherapy (Yes vs No) | 5.92 (2.60–13.50) | <0.001 | 3.01 (1.18–7.68) | 0.021 |
| Received adjuvant chemotherapy (Yes vs No) | 1.69 (0.89–3.23) | 0.106 | 1.63 (0.76–3.49) | 0.212 |
| HER2 status (HER2− vs HER2+) | 2.02 (0.82–4.96) | 0.120 | 1.30 (0.50–3.38) | 0.586 |
| Among HER2+ patients: HER2 amplification ratio (per unit increase) | 0.72 (0.48–1.08) | 0.109 | 0.69 (0.43–1.09)c | 0.111 |
Abbreviation: HR, hazard ratio; CI, confidence interval; NE, not estimable.
a
P values for age at diagnosis, CA125 and HER2 amplification ratio were based on Wald test, and P values for all other variables were based on the log-rank test.
b
Based on Wald test.
c
To interpret with caution as there were <10 deaths in the fitted multivariable model.