Abstract
e23504 Background: Small cell osteosarcoma (SCOS) is a rare subtype of osteosarcoma accounting for roughly 1.5% of all osteosarcomas. Its prognosis is slightly worse than conventional osteosarcoma. Exploring demographic trends in patients with a confirmed SCOS diagnosis may provide insight into its epidemiology and allow for earlier diagnosis. The National Cancer Database (NCDB) was analyzed to research the demographic factors in patients diagnosed with SCOS. Methods: A retrospective cohort analysis utilizing the 2004–2020 National Cancer Database (NCDB) included patients with a histologically-confirmed diagnosis of SCOS (ICD-O-3 9185). Demographic factors (age, sex, race, Hispanic status, educational attainment, insurance status, facility type, distance from facility, and Charles-Deyo score) were analyzed via descriptive statistics. Incidence trends were interpreted in regression analysis. The mean survival was compared using the Log Rank (Mantel-Cox) test. Results: A cohort of 102 cases of SCOS were retrieved from the NCDB between 2004–2020. The primary sites for SCOS were the long bones of the lower limb (41%). Most patients were male (69%), White (63%), non-Hispanic (84%) with a mean age for diagnosis of 28 (SD = 18). The mean survival for males was 117 months (95% CI [93,141]), more than twice as long as females with 58 months (95% CI [31,85]). The Log Rank (Mantel-Cox) test reported a chi-square (χ²) value of 6.434, indicating a statistically significant difference between survival curves of males and females (p = 0.01). Residence in a metropolitan area (86%) was more common than other rural or urban areas. The greatest proportion of patients lived in the Middle or South Atlantic region of the United States (68%). The majority of patients were insured (86%), with the most covered by private insurance (64%) or Medicaid (22%). The median household income for each patient was most commonly in the highest quartile of over $74,063 (29%). Patients were diagnosed with SCOS at a steady rate between 2004 to 2020 (R² = 0.0956). Using the AJCC Cancer Staging System, most patients were Stage II (40%) or Stage IV (21%) at diagnosis. As a primary treatment, 87% of patients received chemotherapy. Most patients (91%) had no comorbidities with a Charlson-Deyo score of 0. Conclusions: This is the first time that demographic and socioeconomic factors of SCOS patients have been analyzed from the NCDB, revealing that the mean survival time of patients after receiving a diagnosis was more than double for males than females. SCOS patients are also more likely to live in metropolitan areas, particularly within the Middle or South Atlantic United States. Consistent with earlier reports, SCOS is typically diagnosed in young adults in the long bones of lower limbs. To better understand the impact of demographic factors on the diagnosis, treatment, and overall survival of patients with SCOS, further research is recommended.