Malignant chondroblastoma: NCDB analysis of demographic and socioeconomic factors.
Authors: Cronen Austin , Tade Yanick , Lorber Nitya , Peterson Michael , Khatib Rawaan , Halloum Anas , Nowlen Frances , Kolli Priyanka , Silberstein Peter T. , Lee Daniel , Demangone Michael , Rossi Anthony , Heise Craig , Hsia Beau 
Published: June 2024

e23500 Background: Malignant chondroblastomas are atypical forms of the rare benign chondroid-producing neoplasm known as a chondroblastoma. Chondroblastomas account for less than 1% of all bone tumors and arise in the epiphyses of long bones in young adults. Unlike conventional chondroblastoma, the majority of patients diagnosed with malignant chondroblastomas tend to be older and tumors present at atypical body sites. Therefore investigating trends in diagnosis may yield important insight into its epidemiology. The National Cancer Database (NCDB) was explored to analyze the demographic factors in patients diagnosed with malignant chondroblastoma. Methods: A retrospective cohort analysis utilizing the 2004–2020 National Cancer Database (NCDB) included 67 patients with a histologically-confirmed diagnosis of malignant chondroblastoma (ICD-O-3 Code 9230). Demographic factors (age, sex, race, Hispanic status, insurance status, facility type, distance from facility, and Charlson-Deyo score) were analyzed by descriptive statistics, and incidence trends were interpreted using regression analysis. Results: Between 2004 – 2020, the NCDB identified 67 patients with a confirmed malignant chondroblastoma diagnosis. There was a slightly increasing incidence of patients diagnosed per year (R² = 0.471). The most common primary site was the frontal lobe (60%). Males and females were affected equally (49% and 51%, respectively) with a mean age at diagnosis of 46.5 years (SD = 15.3, Range = 21 – 74 years). The majority of patients were White (90%), non-Hispanic (87%), lived in metropolitan areas (82%), and were privately insured (63%). Treatment facilities primarily consisted of academic programs (48%). Patients lived an average of 27 miles away from the facility (SD = 49, Range = 356.3 miles). Most individuals (76%) had Charlson-Deyo comorbidity scores of 0. Primary treatment methods involved administering radiation therapy (52%). 60 patients (90%) underwent surgical intervention. For valid data, post-surgery survival rates were 100% after 30 days and 93% after 90 days. About half of the patients (57%) survived 5 years after their initial diagnosis. Conclusions: Malignant chondroblastoma is locally aggressive and has metastatic potential. Surgical intervention was the most common treatment (90%), which is consistent with the previous literature. In this study, AJCC staging was not applicable to almost all of the patients (99%). To the best of our knowledge, this is the first NCDB analysis of malignant chondroblastoma patient demographic and socioeconomic factors which addresses a significant gap in knowledge. Most patients were White, non-Hispanic, lived in metropolitan areas and were privately insured. Additional investigation is required to enhance our understanding of how demographic and socioeconomic factors influence the diagnosis, staging, and treatment of individuals with malignant chondroblastoma.