Abstract C47: The impact of racial/ethnic disparities on survival for children and young adults with chest wall sarcoma: A population-based study

Purpose: To determine whether there are racial/ethnic disparities in disease presentation and survival outcomes among children and young adults with chest wall sarcomas. Methods: The Surveillance, Epidemiology and End Results (SEER) database from 1973-2013 was analyzed for all patients less than 24 years old and diagnosed with chest wall based on primary tumor histology and primary tumor site. Tumor histology was categorized as skeletal for histologic subtypes arising from bone and extra-skeletal for histologic subtypes arising from soft tissues. Tumor sites included thorax, clavicle, sternum and ribs. We performed multivariate logistic regression to investigate the association of race/ethnicity with advanced stage of disease at presentation and likelihood of undergoing surgical resection after adjusting for age, sex, treatment, tumor size and sarcoma type. Overall survival (OS) was evaluated using Cox regression to estimate hazard ratios with 95% confidence intervals. All statistics were calculated with SPSS Statistics Version 23. Results: A total of 598 patients were identified and included 363 non-Hispanic whites (61%), 129 Hispanics (22%), 57 non-Hispanic blacks (10%), and 49 other race/ethnicity (8%). The mean age at diagnosis was 14 + 6.6 years. Most patients presented with advanced stage disease defined as regional or distant disease (393, 66%). Race/ethnicity was not associated with stage of disease at presentation. However, patients with advanced stage disease were more likely to have a skeletal sarcoma (OR= 2.55, 95% CI: 1.71-3.80), tumor size ≥8 cm (OR= 3.66, 95% CI: 2.35-5.71) and undergone radiation therapy (OR= 1.80, 95% CI: 1.22-2.67). Those who underwent surgical resection were less likely to present with advanced disease (OR=0.34; 95% CI: 0.20-0.59). The 5- and 10-year OS for the entire cohort were 62% and 58%, respectively. Non-Hispanic blacks had a worse 5-year and 10-year OS compared to Non-Hispanic whites (54% versus 65%, 48% versus 60%, respectively). In the univariate analysis, non-Hispanic Blacks were 63% more likely to die than non-Hispanic whites (95% CI 1.07-2.49); however, this association was mitigated after controlling for age at diagnosis, sex, tumor type, tumor size, disease stage, surgical resection and radiation treatment in the multivariate analysis. In the multivariate analysis, predictors of worse OS included older age at diagnosis (HR 1.05, 95% CI 1.03-1.07), tumor size > 8cm (HR 2.15, 95% CI 1.50-3.10), regional disease (HR 1.79, 95% CI 1.19-2.69), distant disease (HR 3.99, 95% CI 2.67-5.96), and failure to undergo surgical resection (HR 2.08, 95% CI 1.55-2.81). Most patients (79%) underwent surgical resection. However, non-Hispanic blacks were less likely than non-Hispanic whites to undergo surgical resection even after controlling for sex, age at diagnosis, tumor type, tumor size, disease stage, and radiation therapy (OR 0.49, 95% CI 0.25-0.97). Conclusions: Non-Hispanic black children and young adults with chest wall sarcomas have decreased overall survival compared to non-Hispanic whites. In addition, Non-Hispanic blacks are less likely to undergo surgical resection of their tumors which may contribute to the survival disparities identified in this study. Citation Format: Michael Joseph, Emma Hamilton, Winston Huh, Andrea Hayes-Jordan, Mary Austin. The impact of racial/ethnic disparities on survival for children and young adults with chest wall sarcoma: A population-based study. [abstract]. In: Proceedings of the Ninth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2016 Sep 25-28; Fort Lauderdale, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2017;26(2 Suppl):Abstract nr C47.