Odds of Stage IV Bone Cancer Diagnosis Based on Socioeconomic and Geographical Factors: A National Cancer Database (NCDB) Review

Background: There are significant differences in prognosis for osteosarcoma, Ewing sarcoma, chondrosarcoma, and chordomas based on the stage at diagnosis. The five-year survival of these bone cancers varies from 75-87% at an early stage of diagnosis and falls to 27-55% at a late stage of diagnosis. Patients and methods: This study retrospectively evaluated the odds of stage I vs stage IV cancer at the time of diagnosis in patients with primary malignant bone tumors (osteosarcoma, chondrosarcoma, Ewing sarcoma and chordoma) diagnosed in the National Cancer Database (NCDB) between 2004 and 2018. Cross tabulations with Chi-square analysis were performed to evaluate frequencies of different socioeconomic and geographical characteristics between patients with stage I vs stage IV cancer. Multivariable binary logistic regression was performed to evaluate relationships between socioeconomic and geographical factors and the odds of stage IV cancer at the time of diagnosis. Statistical significance was set at α = 0.05. Results: 8882 patients with stage I and 3063 with stage IV primary malignant bone tumors were identified. The odds of stage IV bone cancer at diagnosis are increased for patients on Medicaid (odds ratio [OR] = 1.298, 95% confidence interval [CI]: 1.043-1.616) or Medicare (OR = 1.795, 1.411-2.284). Odds of stage IV bone cancer at diagnosis were decreased with female sex (OR = 0.733, 0.671-0.800), private insurance (OR = 0.738, 0.601-0.905), and those treated at community cancer programs (OR = 0.542, 0.369-0.797), comprehensive cancer program (OR = 0.312, 0.215-0.452), or academic/research facilities (OR = 0.370, 0.249-0.550). No significant relationship was identified between the stage at diagnosis and race, ethnicity, Charlson-Deyo score, or education level. Stage IV cancer at diagnosis showed was proportionally lower in chondrosarcomas (17.1%) and chordomas (2.1%) than osteosarcomas (45.0%) and Ewing sarcomas (35.8%). Conclusion: Odds of stage IV bone cancer at diagnosis are greater with male sex, Medicaid or Medicare insurance status, or treatment at community cancer programs. Providers should have a low suspicion for additional evaluation when treating patients with symptoms of bone cancer and should be aware of these disparities when treating people in these groups. This is to the authors' knowledge the first such study conducted through the NCDB.