Reduced Risk of All-Cause, Cancer-, and Cardiovascular Disease-Related Mortality among Patients with Primary Malignant Cardiac Tumors Receiving Chemotherapy in the United States

Primary malignant cardiac tumors (PMCTs) are rare but lethal neoplasms. There are limited evidence-based treatment guidelines for PMCTs. We evaluated the relation of chemotherapy with mortality outcomes in patients with PMCTs in the United States. Data were from patients aged ≥ 20 years from the Surveillance, Epidemiology, and End Results program who were diagnosed with PMCTs from 2000 to 2020. Cox regression, competing risk, and propensity score analyses were performed to estimate hazard ratios (HR) and confidence intervals (CI). About 53% of the 563 patients with PMCTs received chemotherapy as the first course of treatment. During a mean follow-up of 24.7 months (median: 10), 458 deaths occurred with 81.7% and 9.4% due to cancer and cardiovascular disease (CVD), respectively. In models adjusted for sociodemographic and clinico-pathophysiological factors including histology, receipt of chemotherapy was associated with low risk for all-cause (HR: 0.56, 95%CI: 0.45-0.69), cancer (HR: 0.63, 95%CI: 0.50-0.80) and CVD mortality (HR: 0.27, 95%CI: 0.12-0.58). Patients who had both chemotherapy and surgery had the lowest risk for all-cause and cancer mortality. This study suggests that the subpopulations of patients with PMCTs who receive chemotherapy may have better prognosis than those who do not receive this therapy regardless of histology.