Table 5: Multivariate analyses for the effect of comorbidity on overall and disease-specific mortality according to histological subtype.

Histological subtypeNo. of patientsOverall mortality Disease-specific mortality
5-year (%)HR (95% CI)5-year (%)HR (95% CI)

Ewing/osteosarcoma
 No149541531
 Mild10701.02 (0.43–2.42)600.80 (0.31–2.09)
 Moderate9671.12 (0.47–2.66)560.88 (0.33–2.36)
 Severe8380.79 (0.27–2.32)370.67 (0.20–2.26)
Others
 No219301221
 Mild27451.42 (0.81–2.48)411.54 (0.78–3.05)
 Moderate18442.36 (1.18–4.70)281.05 (0.37–2.97)
 Severe13772.44 (1.30–4.58)462.07 (0.94–4.56)

Note: abbreviations: HR: hazard ratio, CI: confidence interval. Adjusted for age, stage at diagnosis, tumor size, soft tissue involvement, malignancy grade, surgical margin, and chemotherapy.