Infantile hemangioma
benign
Bright red raised lesion; appears weeks after birth, grows, then regresses over years. GLUT1⁺.
Most common tumor of infancy
Propranolol if near eye or airway
Tiny bright red papules; don't regress.
Adults; number rises with age
Trunk
Pyogenic granuloma
lobular capillary hemangioma
Fast-growing polypoid red lesion that bleeds and ulcerates easily.
Skin or gums; pregnancy, minor trauma
Gum nodule in pregnancy; may regress after delivery
Cavernous hemangioma
benign
Large dilated blood-filled channels.
Liver (most common benign liver tumor), brain (seizures, bleeding)
Don't biopsy a liver hemangioma — it bleeds
Small, red-blue, exquisitely tender; from modified smooth muscle of thermoregulatory glomus bodies.
Under the fingernail
Cold sensitivity, point tenderness
Cystic hygroma
lymphangioma
Cavernous lymphatic malformation in the neck.
Turner syndrome (45,X)
Neck mass on prenatal ultrasound
Bacillary angiomatosis
infection
Red-purple papules of capillary proliferation with neutrophils; bacteria on Warthin-Starry stain.
Bartonella henselae/quintana in AIDS
Mimics Kaposi · azithromycin or doxycycline
Kaposi sarcoma
low-grade malignant
Purple patches → plaques → nodules; spindle cells with slit-like vessels and lymphocytes.
HHV-8: classic (older Mediterranean/Eastern European men, legs), AIDS (aggressive, mucosa, GI, lung), endemic African, transplant
ART, lower immunosuppression, chemotherapy
Angiosarcoma
high-grade malignant
Malignant endothelial tumor; CD31⁺; aggressive.
Elderly scalp/face skin, breast after radiation, liver (vinyl chloride, arsenic, Thorotrast)
Poor prognosis
Malignant lymphatic tumor.
Chronic lymphedema after mastectomy and node dissection (Stewart-Treves)
Purple nodules on a swollen arm
Hereditary hemorrhagic telangiectasia
Autosomal dominant malformation of vessels: telangiectasias and AVMs.
Skin, lips, nose, GI tract, lung, liver, brain
Recurrent nosebleeds, GI bleeding, paradoxical emboli