Clinical characteristics associated with primary cardiac angiosarcoma outcomes: a surveillance, epidemiology and end result analysis

Abstract
Primary cardiac angiosarcoma (PCAS) is a rare type of tumour. Furthermore, descriptions of the demographic features and prognostic factors of PCAS patients have been poorly reported. A population cohort study was conducted using retrospectively extracted data from the SEER (Surveillance, Epidemiology and End Results) database for patients with histological diagnoses of PCAS; the extracted information included demographic, treatment and outcome data. A total of 168 cases of PCAS from 1973 to 2013 were included. The mean age at diagnosis was 44.4 ± 15.5 years. PCAS was more prevalent in men than in women. The majority of PCAS patients were white (67.3%), while the incidence of PCAS in black individuals was relatively infrequent (19.0%). In addition, 87 cases were classified as distant stage, 44 as regional stage, and 33 as localized stage. The median disease-specific survival (DSS) was 7.22 months, and the 1-, 2- and 5-year DSS rate for PCAS patients was 34.7%, 14.3% and 10.2%, respectively. Further multivariate analyses showed that an age at (greater than or equal to) 45 years (HR 2.165), no radiotherapy (HR 1.629), tumour size > 5 cm (HR 3.182), and the summary stage was associated with worse PCAS-related survival. Cancer-directed surgery and radiotherapy significantly improved the DSS for patients with PCAS (P < 0.05). The C-index of the nomograms was 0.706 (95% CI 0.654–0.758), and the calibration curves showed good agreement between the nomogram prediction and actual observation. PCAS is a rare cancer that is prone to have poor prognoses. To understand PCAS more thoroughly, more cases with adequate information are needed.