Rapid Review·Cardiovascular
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PATHOLOGY
T3Take a glanceVascular Tumors & Malformations
Focus on
Benign versus malignant vessel tumours, the exposure that names each one, and the malformations that shunt blood the wrong way.
Key takeaways
Benign vessel tumours
Hemangioma
a benign capillary tumour.- Infantile (strawberry) hemangiomas appear in the first weeks of life and regress by about 5 to 8 years, so the answer is usually observation.
- Cherry hemangiomas are common in adults and do NOT regress.
Pyogenic granuloma
a rapidly growing red polypoid lesion that bleeds easily. Linked to trauma and pregnancy, and despite the name it is neither pyogenic nor a granuloma.Glomus tumour
benign, painful, red-blue tumour under the nail bed, arising from the modified smooth muscle of the thermoregulatory glomus body.Bacillary angiomatosis
a benign vascular proliferation caused by Bartonella in immunocompromised (HIV) patients. Can mimic Kaposi sarcoma, and the distinction matters because this one is curable with antibiotics.Cystic hygroma
a lymphatic malformation of the neck, associated with Turner syndrome.Malignant vessel tumours
Kaposi sarcoma
malignant and HHV-8 driven, of endothelial origin. Seen in AIDS, transplant recipients, and older Eastern European men.Angiosarcoma
a highly aggressive malignant endothelial tumour.- Hepatic angiosarcoma is linked to vinyl chloride, arsenic, and Thorotrast.
- Also arises in chronic lymphedema after mastectomy (Stewart-Treves syndrome) and after radiation.
| Tumour | Benign or malignant | Signature association |
|---|---|---|
| Infantile (strawberry) hemangioma | Benign | Appears in first weeks, regresses by 5 to 8 years |
| Cherry hemangioma | Benign | Adults, does not regress |
| Pyogenic granuloma | Benign | Trauma, pregnancy; bleeds easily |
| Glomus tumour | Benign | Painful, under the nail bed |
| Bacillary angiomatosis | Benign proliferation | Bartonella in HIV; mimics Kaposi |
| Cystic hygroma | Benign malformation | Turner syndrome |
| Kaposi sarcoma | Malignant | HHV-8; AIDS, transplant, older Eastern European men |
| Angiosarcoma | Malignant | Vinyl chloride, arsenic, Thorotrast; lymphedema; radiation |
The malformations that shunt blood the wrong way
Arteriovenous malformation
an abnormal high-flow artery-to-vein connection that bypasses the capillary bed, raising the risk of high-output cardiac failure. The most common cause of intracranial hemorrhage in children.Hereditary hemorrhagic telangiectasia (Osler-Weber-Rendu)
autosomal dominant. Mutations in the genes for TGF-beta receptors weaken the vessel wall, blood pools in the post-capillary venules, and small and large arteriovenous shunts form.- Findings: blanching telangiectasias on skin and mucous membranes including the tongue, recurrent epistaxis, and arteriovenous malformations in the brain (hemorrhagic stroke), lung (hemoptysis, and platypnea, dyspnea that worsens on sitting up), liver, GI tract (bleeding), and kidney (hematuria).
- Complications: the systemic high-volume shunts cause high-output heart failure and pulmonary hypertension; pulmonary AVMs let clots and bacteria bypass the lung filter (paradoxical embolism, brain abscess); and the chronic bleeding gives iron deficiency anemia.
An HIV patient has purple vascular skin lesions. What must you rule out before calling it Kaposi sarcoma, and why does it matter?
Bacillary angiomatosis (Bartonella): it looks the same in the same population, but it is cured with antibiotics.
How it's tested
Hepatic angiosarcoma is classically linked to occupational vinyl chloride, arsenic, or Thorotrast, so an occupational history in a liver tumour stem is pointing here. Kaposi sarcoma is HHV-8 driven and seen in AIDS, and the distinction that matters clinically is from bacillary angiomatosis, which looks similar in the same population but is caused by Bartonella and responds to antibiotics. In an infant, a strawberry hemangioma is managed by observation, because it regresses on its own. On the malformation side, an adult with recurrent epistaxis, mucocutaneous telangiectasias and a family history has hereditary hemorrhagic telangiectasia, and the complication to anticipate is a high-output state from arteriovenous shunting.
Go deeper
First Aid 2026 — CV/Pathology (vascular tumours and malformations) · B&B — Vascular tumours · Mehlman — HY Pathology (Kaposi vs bacillary angiomatosis, angiosarcoma exposures), HY Cardio (HHT and high-output failure)
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