Primary intraosseous hemangioma
Updates to Article Attributes
Primary intraosseous haemangiomas, also known as haemangiomas of bone, are benign tumours of small and large calibre vascular channels arising within bone 4, seen most frequently in the vertebrae and next most frequently in the skull.
Terminology
Given their non-neoplastic nature, some authors ref refer to these lesions as vascular malformations or harmatomashamartomas. They have not been included in the 2018 ISSVA classification 6.
Epidemiology
Intraosseous haemangiomas are common, with vertebral haemangiomas seen in ~10% of the adult population 4. They are slightly less commonly encountered in men (M:F = 0.7:1) and most commonly seen in the 5th decade of life but can occur at any age 4.
Diagnosis
Diagnostic criteria according to the WHO classification of soft tissue and bone tumours (5th edition) 4:
typical imaging appearances
on histology, thin-walled blood vessels with a lining of single non-atypical endothelial cells
Clinical presentation
These tumours are slow-growing and are most commonly asymptomatic (~99% 4) unless they exert mass effect on sensitive structures, present as a swelling or a palpable mass, especially in the skull, or when large and strategically located, they may present with a pathological fracture 4.
If they are high-flow lesions, shunt-related symptoms may also be present.
Pathology
Primary intraosseous haemangiomas are slow-growing vascular tumours, usually located in the medullary cavity 4. The aetiology and pathogenesis are unknown 4. Most commonly they are located in the vertebrae (of the thoracic spine 5), followed by the skull and facial bones, followed by long bones where they preferentially involve the metaphysis or diaphysis 4. They are classified as benign, but rarely may be locally aggressive.
Microscopic appearance
Intraosseous haemangiomas come in four histologic types 1,2:
intraosseous cavernous haemangioma
intraosseous capillary haemangioma
intraosseous arteriovenous haemangioma (may represent congenital arteriovenous malformations) 2
intraosseous venous haemangioma
Histologically, intraosseous haemangiomas demonstrate hamartomatous vascular tissue within endothelium surrounding bone trabeculae and permeating marrow, but may also contain fat, smooth muscle, fibrous tissue, and thrombi 4.
It should be noted that it is difficult to distinguish between the various histological types on imaging, except for those with a large arterial component ref.
Location-specific subtypes
Radiographic features
Plain radiograph
Plain radiographs are usually the first line of imaging and may be sufficient in vertebral or calvarial lesions. Findings include ref:
prominent trabecular pattern
sclerotic vertebra with vertical trabeculae: corduroy sign
lytic calvarial lesions with spoke-wheel appearance
irregular and lytic in long bones, with a honeycomb appearance
CT
Usually appears as a mixed or sclerotic bone lesion with internal fat. CT allows for better visualisation of thickened vertical trabeculation, which can give the polka-dot appearance on axial images and the corduroy sign on coronal and sagittal images 5.
MRI
Signal intensity is somewhat variable, depending largely on the amount of fat content:
-
T1
high is more common (lipid-rich)
intermediate to low signal intensity is seen in lipid-poor haemangiomas 3
T2: high
T1 C+ (Gd): enhancement is often present
STIR: intermediate or high
MRI is the ideal modality to demonstrate mass-effect complications, such as neural impingement and extraosseous extension.
Nuclear medicine
Bone scintigraphy is usually normal but may show increased or decreased uptake ref.
Treatment and prognosis
If incidental with typical imaging appearances no work-up or follow-up is required 5. Treatment is reserved for symptomatic lesions, and a number of options exist ref:
embolisation to reduce intraoperative blood loss
surgical resection, especially if complicated by spinal cord compression
intralesional ethanol injection
Local recurrence rates are low 4.
Differential diagnosis
When internal fat is present and the imaging findings are not typical, the following differential diagnosis can be considered 5:
-<p><strong>Primary intraosseous haemangiomas</strong>, also known as <strong>haemangiomas of bone</strong>, are benign tumours of small and large calibre vascular channels arising within bone <sup>4</sup>, seen most frequently in the <a href="/articles/vertebra">vertebrae</a> and next most frequently in the <a href="/articles/skull">skull</a>.</p><h4>Terminology</h4><p>Given their non-neoplastic nature, some authors <sup>ref</sup> refer to these lesions as vascular malformations or harmatomas. They have not been included in the <a href="/articles/issva-classification-of-vascular-anomalies" title="ISSVA classification of vascular anomalies">2018 ISSVA classification</a> <sup>6</sup>.</p><h4>Epidemiology</h4><p>Intraosseous haemangiomas are common, with<a href="/articles/vertebral-haemangioma" title="Vertebral haemangioma"> vertebral haemangiomas</a> seen in ~10% of the adult population <sup>4</sup>. They are slightly less commonly encountered in men (M:F = 0.7:1) and most commonly seen in the 5<sup>th</sup> decade of life but can occur at any age <sup>4</sup>.</p><h4>Diagnosis</h4><p>Diagnostic criteria according to the <a href="/articles/who-classification-of-tumors-of-bone">WHO classification of soft tissue and bone tumours (5th edition)</a> <sup>4</sup>:</p><ul>- +<p><strong>Primary intraosseous haemangiomas</strong>, also known as <strong>haemangiomas of bone</strong>, are benign tumours of small and large calibre vascular channels arising within bone <sup>4</sup>, seen most frequently in the <a href="/articles/vertebra">vertebrae</a> and next most frequently in the <a href="/articles/skull">skull</a>.</p><h4>Terminology</h4><p>Given their non-neoplastic nature, some authors <sup>ref</sup> refer to these lesions as vascular malformations or hamartomas. They have not been included in the <a href="/articles/issva-classification-of-vascular-anomalies" title="ISSVA classification of vascular anomalies">2018 ISSVA classification</a> <sup>6</sup>.</p><h4>Epidemiology</h4><p>Intraosseous haemangiomas are common, with<a href="/articles/vertebral-haemangioma" title="Vertebral haemangioma"> vertebral haemangiomas</a> seen in ~10% of the adult population <sup>4</sup>. They are slightly less commonly encountered in men (M:F = 0.7:1) and most commonly seen in the 5<sup>th</sup> decade of life but can occur at any age <sup>4</sup>.</p><h4>Diagnosis</h4><p>Diagnostic criteria according to the <a href="/articles/who-classification-of-tumors-of-bone">WHO classification of soft tissue and bone tumours (5th edition)</a> <sup>4</sup>:</p><ul>