Tumor Biology Impacts Survival in Surgically Managed Primary Hepatic Vascular Malignancies

Background: Hepatic angiosarcoma (AS) and hepatic epithelioid hemangioendothelioma (HEHE) are rare primary hepatic vascular malignancies (PHVM) that remain poorly understood. To guide management, we sought to identify factors and trends predicting survival after surgical intervention using a national database. Materials and methods: In a retrospective analysis of the National Cancer Database patients with a diagnosis of PHVM were identified. Clinicopathologic factors were extracted and compared. Overall survival (OS) was estimated and predictors of survival were identified. Results: Three hundred ninty patients with AS and 216 with HEHE were identified. Only 16% of AS and 36% of HEHE patients underwent surgery. The median OS for patients who underwent surgical intervention was 97 months, with 5-year OS of 30% for AS versus 69% for HEHE patients (P< 0.001). Tumor biology strongly impacted OS, with AS histology (Hazard Ratio [HR] of 3.61 [1.55-8.42]), moderate/poor tumor differentiation (HR = 3.86 [1.03-14.46]) and tumor size (HR = 1.01 [1.00-1.01]) conferring worse prognosis. The presence of metastatic disease in the surgically managed cohort (HR = 5.22 [2.01-13.57]) and involved surgical margins (HR = 3.87 [1.59-9.42]), were independently associated with worse survival. Conclusions: In this national cohort of PHVM, tumor biology, in the form of angiosarcoma histology, tumor differentiation and tumor size, was strongly associated with worse survival after surgery. Additionally, residual tumor burden after resection, in the form of positive surgical margins or the presence of metastasis, was also negatively associated with survival. Long-term clinical outcomes remain poor for patients with the above high-risk features, emphasizing the need to develop effective forms of adjuvant systemic therapies for this group of malignancies.