Table 2.
Factors associated with development of second primary cancer risks.
| SHR | 95% CI | p | |
|---|---|---|---|
| Age | |||
| 20–40 | ref | ||
| 41–60 | 1.206 | 1.100–1.323 | <0.001 |
| 61–70 | 1.648 | 1.494–1.818 | <0.001 |
| 71–80 | 1.332 | 1.197–1.482 | <0.001 |
| Race | |||
| White | ref | ||
| Black | 1.101 | 1.015–1.194 | 0.021 |
| Other | 0.993 | 0.914–1.079 | 0.860 |
| Histological type | |||
| IDC | ref | ||
| ILC | 0.974 | 0.881–1.077 | 0.600 |
| Mix | 1.092 | 1.004–1.188 | 0.039 |
| Other | 0.942 | 0.867–1.024 | 0.160 |
| Stage* | |||
| I | ref | ||
| II | 0.945 | 0.896–0.996 | 0.034 |
| III | 0.814 | 0.750–0.884 | <0.001 |
| HR | |||
| Negative | ref | ||
| Positive | 0.880 | 0.829–0.933 | <0.001 |
| Chemotherapy | |||
| With | ref | ||
| Without | 0.88 | 0.832–0.931 | <0.001 |
| Radiotherapy | |||
| With | ref | ||
| Without | 1.161 | 1.109–1.217 | <0.001 |
p values obtained from the multivariable Fine and Gray competing model.
*
Stage classification according to the 8th edition of AJCC staging.
SHR, Subdistribution hazard ratio; IDC, Infiltrating duct carcinoma; ILC, Invasive lobular carcinoma; Mixed, mix of IDC and ILC; HR, Hormone receptor.