Epithelioid hemangioendothelioma (EHE)

Epithelioid hemangioendothelioma is a vascular tumor that can develop in the skin, soft tissues, bones, or deep organs, most frequently the lungs and the liver.   These tumors typically arise from a medium to large vein. Malignancy potency is intermediate to high and comparable with angiosarcoma. The cause of this tumor is unclear and can occur at almost any age.  

Symptoms/History

Epithelioid hemangioendothelioma typically develop as a single, asymptomatic mass and symptoms may arise depending on the location of the lesions in the lungs, liver, bones, or skin. 

Diagnosis

Clinical Exam. The tumors can have variable appearance and symptoms based on the location of involvement. Patients will often require additional diagnostic testing such as imaging or biopsy. 

Imaging. X-ray of EHE may show calcification. Ultrasound is used as a screening tool for lesions in the liver. In children, MRI is preferred because it does not use any ionizing radiation. In adults, CT scan may be sufficient to characterize the tumor’s shape and size. 

Pathology. A biopsy of the lesion can help confirm the diagnosis, and will show findings of poorly formed vascular channel lined by large epithelioid cells in an inflammatory stroma. Vascular markers including CD31, factor VIII-related antigen, and CD34 will typically be positive. 

Genetics. Translocation t(1;3)(p36.3;q25) resulting in the WWTR1-CAMTA1 chimeric gene has been identified in EHE this may be helpful in making the diagnosis in the future. 

Treatment

Rarely EHE may spontaneously resolve.  It is typically resistant to radiation therapy or chemotherapy.  In cases with multiple metastases, treatment is difficult and prognosis guarded. Surgery remains an effective treatment for local recurrences.