Hemangioendothelioma
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Associate Editor(s)-in-Chief: Maria Fernanda Villarreal, M.D. [2]
Synonyms and keywords: Infantile hemangioendothelioma; Kaposiform hemangioendothelioma; Retiform hemangioendothelioma; Epithelioid hemangioendothelioma
Overview
Hemangioendothelioma is a rare group of benign or malignant vascular neoplasms. Hemangioendotheliomas commonly present with an enlarging mass and have been reported in the head and neck, intestines, lungs, lymph nodes, pleura, retroperitoneum,or stomach. Surgical resection, radiotherapy, and chemotherapy is the treatment of choice for hemangioendothelioma.
Historical Perspective
- Hemangioendothelioma was first described by Sharon Weiss, an American pathologist, in 1986.
Classification
- Hemangioendothelioma may be classified into 4 groups:
- Epithelioid hemangioendothelioma
- Kaposiform hemangioendothelioma
- Retiform hemangioendothelioma
- Infantile hemangioendothelioma
- Type I
- Multiple vascular channels
- Formed by an immature endothelial lining
- Stromal separation from bile ductules
- Type II:
- Disorganized appearance and hypercellular
- There are no bile ductules
Pathophysiology
- The pathogenesis of hemangioendothelioma is characterized by
- Hemangioendotheliomas tend to occur around medium to large venous structures.
- There are no genetic mutations associated with the development of hemangioendothelioma.
- On gross pathology, characteristic findings of hemangioendothelioma, include:
- No hallmark features
- Size may range up to 18 cm.
- On microscopic histopathological analysis, characteristic findings of hemangioendothelioma, include:
- Large epithelioid perivascular cells
- Abundant pale eosinophilic cytoplasm
- Cytoplasmic vacuolation (some cells) (also known as "blister cells") - key feature.
- May form lumen and have red blood cells within
- Vesicular nucleus with prominent nucleolus in some cells
- Tuft-like projections into capillaries.
Papillary intralymphatic hemangioendothelioma
- Papillary tufts
- Central hyaline core lined by hobnail-like endothelial cells protruding into the lumina
Retiform hemangioendothelioma
- Infiltrative neoplasm composed of elongated arborizing vessels
- Arranged in an anastomosing pattern
- Lined by a single layer of "hobnail-like" endothelial cells (protrude within the narrow lumina)
Kaposiform hemangioendothelioma
- Composed of several solid poorly circumscribed nodules
- Nodules composed of a mixture of small capillaries and solid lobules
- Arranged in a glomeruloid pattern
- On immunohistochemistry, characteristic findings of hemangioendothelioma, include:
- Positive CD31
- Positive CD34
- Positive Factor VIII
Causes
- Common causes of hemangioendothelioma, include:
Differentiating hemangioendothelioma from other Diseases
- Hemangioendothelioma must be differentiated from other diseases that cause [clinical feature 1], [clinical feature 2], and [clinical feature 3], such as:
- Hepatoblastoma
- Hemangioma
- Angiosarcoma
Epidemiology and Demographics
- The prevalence of hemangioendothelioma is approximately [number or range] per 100,000 individuals worldwide.
- In [year], the incidence of hemangioendothelioma was estimated to be [number or range] cases per 100,000 individuals in [location].
Age
- Patients of all age groups may develop hemangioendothelioma.
- Hemangioendothelioma is more commonly observed among patients aged [age range] years old.
- Hemangioendothelioma is more commonly observed among [elderly patients/young patients/children].
Gender
- Hemangioendothelioma affects men and women equally.
- [Gender 1] are more commonly affected with hemangioendothelioma than [gender 2].
- The [gender 1] to [Gender 2] ratio is approximately [number > 1] to 1.
Race
- There is no racial predilection for hemangioendothelioma.
Risk Factors
- Common risk factors in the development of hemangioendothelioma, include:
- Oral contraceptives
- Polyvinyl chloride
Natural History, Complications and Prognosis
- The majority of patients with hemangioendothelioma are symptomatic at the time of diagnosis.[1]
- Early clinical features will depend on the subtype of hemangioendothelioma. Common clinical features, include:
- If left untreated, the majority of patients with hemangioendothelioma may progress to develop [manifestation 1], [manifestation 2], and [manifestation 3].
- Common complications of hemangioendothelioma, include:
- Prognosis is generally poor, and the 5-year survival rate of patients with hemangioendothelioma is approximately 55%
Diagnosis
Symptoms
- Hemangioendothelioma is usually asymptomatic.
- Symptoms of hemangioendothelioma may include the following:
- [symptom 1]
- [symptom 2]
- [symptom 3]
- [symptom 4]
- [symptom 5]
- [symptom 6]
Physical Examination
- Patients with hemangioendothelioma usually may be well-appearing.
- Physical examination may be remarkable for:
- [finding 1]
- [finding 2]
- [finding 3]
- [finding 4]
Laboratory Findings
- There are no specific laboratory findings associated with hemangioendothelioma.
Imaging Findings
- On CT, characteristic findings of hemangioendothelioma, include:
Hepatic Hemangioendothelioma
- Multiple hypo-attenuating lesions in both hepatic lobes
- That coalesce to form larger confluent hypo-attenuating regions in a peripheral or subcapsular distribution
- Halo or target pattern of enhancement in larger lesions
- Subcapsular lesion often present with capsular retraction
- Located in a predominantly peripheral distribution, with coalescence as individual nodules.
- On MRI, characteristic findings of hemangioendothelioma, include:
Hepatic Hemangioendothelioma
- T1: hypointense lesions relative to normal liver parenchyma on unenhanced T1-weighted images
- T2: heterogeneously increased signal intensity
- C+ (Gd): some lesions demonstrate either a peripheral halo or a target-type enhancement pattern after administration of a gadolinium-based contrast agent, with occasional observation of a thin peripheral hypointense rim
Treatment
Medical Therapy
- There is no treatment for hemangioendothelioma; the mainstay of therapy is supportive care.
Surgery
- Surgery is the mainstay of therapy for hemangioendothelioma.
- The recurrence rate after surgery of hemangioendothelioma. is approximately 40%
Prevention
- There are no primary preventive measures available for hemangioendothelioma.