Trends in primary malignant bone cancer incidence and mortality in the United States, 2000-2017: A population-based study.

Background: Primary malignant bone cancers have extremely low incidence, resulting in poor evaluation of their epidemiological characteristics. The objective of this study was to investigate trends in the incidence of primary malignant bone cancers and related mortality. Materials and methods: Data from patients diagnosed with malignant bone cancers from 2000 to 2017 in the Surveillance Epidemiology and End Results database were retrospectively analyzed. Annual age-adjusted incidence and mortality were calculated, and the annual percentage change analyzed. Further, characteristics including patient age and sex, as well as the primary site and stage of different tumor types, were analyzed. Results: The overall age-adjusted incidence rate of primary malignant bone cancers was 7.70 per million people per year, and incidence rates had increased in patients between 60 and 79 years old, or with tumor size ≥ 8 cm. The incidence of chordoma increased significantly (annual percentage change (APC), 3.0 % per year), while those of WHO grade I and II primary bone cancers decreased. During 2000-2017, the mortality rate attributable to malignant bone cancers across the entire United States was 4.41 per million people per year. A positive mortality trend was observed during the study period (APC = 0.7 %, 95 % confidence interval: 0.0 %-1.5 %). Patients with osteosarcoma, and those who were female or of white ethnicity showed significant increasing trends in mortality rate. Conclusions: Different tumor types have variable epidemiological manifestations, in terms of incidence and mortality, and exhibited altered trends over recent years. These variables can provide guidance to inform allocation of medical resources.