Does histology predict outcome for malignant vascular tumors of the liver?

Background and Objectives Malignant vascular tumors (MVT) of the liver are uncommon and poorly understood. We hypothesized that tumor histology is a predominant factor associated with survival in these tumors. Methods Patients with malignant histopathologic diagnoses of hepatic angiosarcoma (AS), hemangioendothelioma (HE) and its epithelioid variant (EHE), or hemangiopericytoma (HP) were identified using the SEER database (1973-2007). Overall survival (OS) was studied with Kaplan-Meier curves. Results We included 297 patients with MVT (207 AS, 28 HE, 56 EHE, 6 HP). All tumors demonstrated metastatic potential, although EHE and AS had the highest rate of regional or distant metastases (75% each). Patients with AS had the shortest median OS (1 month), however, those undergoing surgery had improved survival (6 months). Three patients with AS underwent liver transplant and lived for 11, 21, and 91 months each. Patients with EHE had the longest overall median survival of 75 months (30-183, P < 0.001). Surgical resection and transplant did not demonstrate an improvement in OS of patients with EHE in multivariable models. Conclusions Histology is an important factor in determining survival for patients with hepatic MVT. Patients with EHE have the longest OS, whereas patients with AS have shorter survival but may benefit from surgery.