Clinical patterns and outcome in epithelioid hemangioendothelioma with or without pulmonary involvement: insights from an internet registry in the study of a rare cancer.

BACKGROUND Epithelioid hemangioendothelioma (EHE) is a rare vascular neoplasm of endothelial origin with clinical behavior intermediate between hemangioma and angiosarcoma. The natural history of EHE is highly variable. This study uses an Internet registry to identify clinical patterns with prognostic significance in EHE. METHODS Cases from the International Hemangioendothioma, Epithelioid Hemangioendothelioma, and Related Vascular Disorders (HEARD) Support Group were evaluated based on demographics, organ involvement, disease progression, presence or absence of pleural effusion, and treatment. Survival among various cohorts was compared using log-rank analysis of Kaplan-Meier plots. RESULTS Two hundred sixty-four patients were identified from April 2004 to November 2009. Fifty-eight cases were excluded because of inadequate information or wrong diagnosis. EHE was more common in female patients (61%). Male gender and age ≥ 55 years were associated with decreased survival. The most commonly affected organs were liver, lung, and bone. No specific organ or combination of organ involvement differentially affected survival, and survival was no different between patients with multiple vs single organ involvement. However, pattern B, defined as lesions without distinct borders (eg, pulmonary infiltrates, pleural effusion, ascites), hemoptysis, or involvement of more than two bones adversely affected survival in all cohorts. CONCLUSION A novel staging system with prognostic value for EHE is proposed. Pleural effusion or other signs of uncontained tumor growth, hemoptysis, and osseous involvement of more than two bones implied worse survival than did localized and discrete tumors, regardless of number of organs involved. A lay registry can provide useful insights into the clinical behavior of a rare cancer.