Table 2.
Univariable and multivariable analysis of each factor’s ability in predicting CSS and OS of secondary osteosarcomas.
| Characteristic | CSS | OS | ||||||
|---|---|---|---|---|---|---|---|---|
| Univariable analysis | Multivariable analysis | Univariable analysis | Multivariable analysis | |||||
| HR (95% CI) | p value | HR (95% CI) | p value | HR (95% CI) | p value | HR (95% CI) | p value | |
| Age at diagnosis | 1.025 (1.015–1.034) | < 0.001 | 1.035 (1.019–1.051) | < 0.001 | 1.024 (1.017–1.03) | < 0.001 | 1.028 (1.017–1.039) | < 0.001 |
| Race | ||||||||
| White | 1 (reference) | 1 (reference) | 1 (reference) | |||||
| Others | 1.65 (1.072–2.540) | 0.023 | 1.708 (1.063–2.742) | 0.027 | 1.255 (0.916–1.720) | 0.158 | ||
| Sex | ||||||||
| Male | 1 (reference) | 1 (reference) | ||||||
| Female | 0.840 (0.565–1.248) | 0.388 | 1 (0.762–1.313) | 1.000 | ||||
| Marital status | ||||||||
| Married | 1 (reference) | 1 (reference) | 1 (reference) | 1 (reference) | ||||
| Un-married | 0.462 (0.295–0.723) | < 0.001 | 1.417 (0.740–2.715) | 0.293 | 0.435 (0.319–0.593) | < 0.001 | 1.136 (0.724–1.782) | 0.578 |
| Year of diagnosis | ||||||||
| 1973–1994 | 2.461 (1.63–3.714) | < 0.001 | 2.644 (1.492–4.686) | < 0.001 | 1.461 (1.07–1.995) | 0.017 | 1.680 (1.116–2.528) | 0.0129 |
| 1995–2015 | 1 (reference) | 1 (reference) | 1 (reference) | 1 (reference) | ||||
| First primary malignancy | ||||||||
| Carcinomas | 1 (reference) | 1 (reference) | 1 (reference) | 1 (reference) | ||||
| Lymphomas/leukemias | 0.672 (0.393–1.152) | 0.148 | 0.921 (0.490–1.731) | 0.798 | 0.626 (0.427–0.920) | 0.017 | 1.133 (0.723–1.776) | 0.585 |
| Sarcomas | 0.315 (0.151–0.659) | 0.002 | 0.592 (0.256–1.370) | 0.221 | 0.505 (0.333–0.767) | 0.001 | 0.913 (0.558–1.494) | 0.717 |
| Others | 0.449 (0.223–0.905) | 0.025 | 1.404 (0.589–3.346) | 0.444 | 0.421 (0.256–0.691) | < 0.001 | 1.021 (0.572–1.823) | 0.945 |
| Radiation for prior malignancies | ||||||||
| Yes | 1 (reference) | 1 (reference) | ||||||
| No | 1.102 (0.740–1.64) | 0.633 | 1.161 (0.883–1.526) | 0.285 | ||||
| Chemotherapy for prior malignancies | ||||||||
| Yes | 1 (reference) | 1 (reference) | 1 (reference) | 1 (reference) | ||||
| No/Unknown | 1.456 (0.954–2.222) | 0.081 | 1.157 (0.688–1.945) | 0.582 | 1.321 (0.993–1.756) | 0.056 | 1.067 (0.748–1.524) | 0.719 |
| Number of primary malignancies | ||||||||
| 1 | 1 (reference) | 1 (reference) | ||||||
| ≥ 2 | 1.472 (0.819–2.648) | 0.196 | 1.411 (0.933–2.133) | 0.103 | ||||
| Latency interval | 1 (0.999–1.003) | 0.868 | 0.999 (0.998–1.001) | 0.737 | ||||
| Tumor location | ||||||||
| Bone | 1 (reference) | 1 (reference) | 1 (reference) | |||||
| Extra-skeleton | 0.086 (0.021–0.348) | < 0.001 | 0.096 (0.023–0.406) | 0.001 | 0.734 (0.503–1.071) | 0.109 | ||
| Primary site | ||||||||
| Extremity | 1 (reference) | 1 (reference) | 1 (reference) | |||||
| Trunk | 1.146 (0.736–1.785) | 0.546 | 1.027 (0.621–1.699) | 0.916 | 1.176 (0.870–1.590) | 0.292 | ||
| Unknown | 2.264 (1.034–4.957) | 0.041 | 1.143 (0.456–2.863) | 0.776 | 1.608 (0.866–2.986) | 0.133 | ||
| Osteosarcomas occurring within the prior radiation field | ||||||||
| No/Unknown | 1 (reference) | 1 (reference) | 1 (reference) | |||||
| Yes | 1.076 (0.609–1.903) | 0.801 | 1.501 (0.986–2.285) | 0.058 | 1.852 (1.124–3.052) | 0.016 | ||
| No first radiation | 1.156 (0.668–1.999) | 0.604 | 1.534 (1.018–2.313) | 0.041 | 1.386 (0.874–2.197) | 0.165 | ||
| Histology | ||||||||
| Non-Pagetic osteosarcoma | 1 (reference) | 1 (reference) | 1 (reference) | 1 (reference) | ||||
| Pagetic osteosarcoma | 4.704 (1.603–13.800) | 0.005 | 2.660 (0.828–8.551) | 0.100 | 2.587 (1.238–5.406) | 0.012 | 1.680 (0.756–3.734) | 0.203 |
| NOS | 2.419 (1.253–4.668) | 0.008 | 1.826 (0.908–3.670) | 0.091 | 1.425 (0.984–2.064) | 0.061 | 1.088 (0.727–1.630) | 0.681 |
| Stage | ||||||||
| Localized | 1 (reference) | 1 (reference) | 1 (reference) | 1 (reference) | ||||
| Regional | 2.486 (1.398–4.421) | 0.002 | 3.292 (1.701–6.370) | < 0.001 | 1.437 (1.008–2.048) | 0.045 | 1.902 (1.283–2.819) | 0.001 |
| Distant | 5.919 (3.145–11.138) | < 0.001 | 5.977 (2.930–12.191) | < 0.001 | 3.696 (2.476–5.517) | < 0.001 | 4.370 (2.775–6.881) | < 0.001 |
| Unstaged | 1.971 (0.894–4.345) | 0.092 | 1.190 (0.477–2.972) | 0.709 | 1.539 (0.953–2.484) | 0.078 | 1.146 (0.663–1.979) | 0.626 |
| Grade | ||||||||
| I | 1 (reference) | 1 (reference) | ||||||
| II | 1.019 (0.106–9.800) | 0.987 | 1.505 (0.325–6.97) | 0.602 | ||||
| III | 1.857 (0.248–13.920) | 0.547 | 1.941 (0.468–8.054) | 0.361 | ||||
| IV | 2.195 (0.299–16.09) | 0.439 | 2.397 (0.587–9.792) | 0.223 | ||||
| Unknown | 2.346 (0.323–17.05) | 0.399 | 2.386 (0.587–9.696) | 0.224 | ||||
| Surgery | ||||||||
| Yes | 1 (reference) | 1 (reference) | 1 (reference) | 1 (reference) | ||||
| No | 2.85 (1.741–4.663) | < 0.001 | 2.346 (1.351–4.075) | 0.002 | 2.417 (1.750–3.339) | < 0.001 | 1.947 (1.343–2.824) | < 0.001 |
| Unknown | 2.298 (1.421–3.716) | < 0.001 | 1.563 (0.782–3.124) | 0.207 | 1.346 (0.954–1.898) | 0.090 | 1.061 (0.654–1.722) | 0.811 |
| Radiation | ||||||||
| Yes | 1 (reference) | 1 (reference) | 1 (reference) | 1 (reference) | ||||
| No | 0.567 (0.364–0.882) | 0.012 | 1.261 (0.664–2.394) | 0.478 | 0.610 (0.447–0.832) | 0.002 | 1.127 (0.758–1.676) | 0.553 |
| Radiation sequence with surgery | ||||||||
| Radiation prior to surgery | 1 (reference) | 1 (reference) | ||||||
| Radiation after surgery | 2.313 (0.301–17.8) | 0.421 | 2.285 (0.540–9.672) | 0.262 | ||||
| No radiation and/or cancer-directed surgery | 1.939 (0.270–13.93) | 0.51 | 2.036 (0.505–8.208) | 0.317 | ||||
| Chemotherapy | ||||||||
| Yes | 1 (reference) | 1 (reference) | 1 (reference) | 1 (reference) | ||||
| No/unknown | 1.672 (1.122–2.491) | 0.012 | 1.363 (0.818–2.271) | 0.234 | 1.631 (1.24–2.145) | < 0.001 | 1.345 (0.958–1.887) | 0.087 |