Exam IV: Pathology of Vascular Interventions Flashcards
Varicose Veins
Abnormally dilated, tortuous veins (serpentine)
Causes prolonged, increased intraluminal pressure and loss of vessel wall support
Involvement: superficial veins of the upper and lower leg
Varicose Veins: Causes and Complications
Familial tendency: development of varicosities due to defective development of vein walls
Most disabling complications:
- Persistent edema in the extremity
- Ischemic skin changes: stasis dermatitis and cutaneous ulcerations due to poor wound healing and superimposed infections; can develop chronic varicose ulcers
Esophageal Varices
Liver cirrhosis causes portal vein hypertension, which opens porto-systemic shunts to increase blood flow into veins at esophagealgastic junction
Development of:
- Esophageal varices
- Rectum (hemorrhoids)
- Periumbilical veins of abdominal wall (caput medusa)
Most important: rupture causes massive (fatal) upper GI hemorrhage
Thrombophlebitis/Phlebothrombosis
Venous thrombosis + inflammation
Venous thrombosis: potentiated by cardiac failure, neoplasia, pregnancy, obesity, post-op state, prolonged bed rest/immobilization
Deep leg veins account for > 90% of thrombophlebitis cases
Riding in a plane for a long time without moving
Surgery on knee or hip, or some type of immobilization then DVT to PE
Thrombophlebitis/Phlebothrombosis: Other Sites
Other sites:
Periprostatic venous plexus (males)
Pelvic venous plexus (females)
Large veins in the skull and the dural sinuses (infection or inflammation)
Portal vein thrombosis
Peritoneal infections, appendicitis, salpingitis, and pelvic abscesses
Thrombophlebitis/Phlebothrombosis: Systemic Hypercoagulability
Carcinoma: adenocarcinomas cause paraneoplastic syndrome, which is a pro-coagulant state caused by factors by the tumor cells
Migratory thrombophlebitis: AKA thrombophlebitis migrans
Trousseau sign of malignancy
Venous thrombi occur in one site and reappear elsewhere
Pulmonary Embolism (PE)
Serious complication of DVT
Fragmentation/detachment of whole venous thrombus
First manifestation of thrombophlebitis
Lymphangitis
Bacterial infections spread into and through lymphatics:
Acute inflammation in lymphatic channels/nodes
Most common agent: Group A β-hemolytic streptococci
Affected lymphatics:
Dilated and filled with inflammatory infiltrate composed of neutrophils (acute) and histiocytes (starting to become chronic)
Extends through the vessel wall
Perilymphatic tissues
Cellulitis or focal abscesses (severe cases)
Clinical Features of Lymphangitis
Painful subcutaneous red streaks extend along the course of lymphatics
Painful enlargement of regional lymph nodes
If lymph nodes fail to block bacteria they drain into venous circulation causing bacteremia or septicemia
Primary Lymphedema
Isolated congenital defect (simple congenital lymphedema)
Familial Milroy disease: heredofamilial congenital lymphedema that causes lymphatic agenesis or hypoplasia
The patient will have no lymph nodes or no nodes in that appendage
Secondary (Obstructive) Lymphedema
Occlusion of lymphatic vessels causing abnormal accumulation of interstitial fluid
Most common causes:
- Malignant tumors obstructing lymphatic channels or regional lymph nodes
- Surgical procedures that remove regional groups of lymph nodes- axillary lymph nodes in radical mastectomy
- Post-irradiation fibrosis
- Filariasis- causes elephantitis; larvae of microfilariae that hatch and block fluid
- Post-inflammatory thrombosis and scarring
Persistence of Lymphedema
Increase of subcutaneous interstitial fibrous tissue
Consequent enlargement of affected part
Induration: peau d’orange (orange peel) appearance and skin ulcers
Lymphedema in Cavities
Milky collections of lymph in various spaces
Rupture of dilated lymphatics due to obstruction of lymphatics by infiltrating tumor
Categories:
Chylous ascites (peritoneum)
Chylothorax (pleural cavity)
Chylopericardium (pericardium)
Benign Hemangiomas
Locally aggressive lesions with infrequent metastases
Rarely highly malignant angiosarcomas
Primary tumors of large vessels:
Aorta, pulmonary artery, and vena cava
Extremely rare and mostly connective tissue sarcomas
Extremely common tumors
Increased numbers of normal or abnormal vessels filled with blood
Majority are superficial lesions in head or neck
Internal lesions: 1/3rd in the liver
Many types/variations: capillary, cavernous, and pyogenic granuloma
Vascular Neoplasms
Endothelium-derived: hemangioma, lymphangioma, angiosarcoma
Arise from cells that support and/or surround blood vessels such as endothelial and glomus cells
Glomus tumor, hemangiopericytoma
Capillary Hemangioma
Most common variant
Composed of a proliferation of benign capillaries
Locations:
Skin and subcutaneous tissues
Mucous membranes of the oral cavities and lips
Liver, spleen, and kidneys
Capillary Hemangioma Characteristics
Bright red to blue
Millimeters to several centimeters in diameter
Flat or elevated
Unencapsulated aggregates of closely packed, thin-walled capillaries- blood-filled and lined by flattened endothelium
Scant connective tissue stroma separates vessels
Lumens may be partially or completely thrombosed
Microscopically: everything looks well maintained, just see a lot of capillaries
Capillary Hemangioma: Strawberry Type
AKA Juvenile hemangioma of the skin of newborns
Extremely common
May be multiple
Grows rapidly in the first few months
Fades at 1 to 3 years of age
Completely regresses by age 7 (75% to 90% of cases)
Cavernous Hemangioma
Large, dilated vascular channels
Less well circumscribed
Involve deep structures
Brain hemangiomas–most problematic because pressure symptoms or rupture
Component of von Hippel-Lindau disease: cerebellum, brain stem, or retina
Cavernous Hemangioma Characteristics
Red-blue, soft, spongy masses
1 to 2 cm in diameter and sharply defined
Composed of large, cavernous blood-filled vascular spaces separated by a modest connective tissue stroma
Intravascular thrombosis with associated dystrophic calcification (will degenerate over time and calcifications develop)
Pyogenic Granuloma
Rapidly growing pedunculated red nodule
Skin, gingival or oral mucosa
Bleeds easily; often ulcerated
Proliferating capillaries
Extensive edema
Acute and chronic inflammatory infiltrate
Purulent debris producing = see neutrophils
Pyogenic: capillary hemangioma + acute inflammation, irritated, ulcerated, or bleeding
Lymphangiomas
Benign lymphatic analogues of blood vessel hemangiomas
Simple (Capillary) Lymphangioma:
Small lymphatic channels
Head, neck, and axillary subcutaneous tissues
Elevated or pedunculated; 1 to 2 cm in diameter
Networks of endothelium-lined spaces distinguished from capillary channels only by the absence of erythrocytes
Cavernous Lymphangioma (Cystic Hygroma)
Neck or axilla of children usually with other genetic conditions like Turner syndrome
Can be very large (15 cm in diameter) and may fill the axilla and form gross deformities of neck
Massively dilated lymphatic spaces lined by endothelial cells and separated by intervening connective tissue stroma
Lymphoid aggregates
Cavernous angioma - RBCs = cystic hygroma
Glomus Tumor (Glomangioma)
Benign, exquisitely painful tumors
Arises from modified smooth muscle cells of the glomus body, which are specialized arteriovenous structure involved in thermoregulation
Located anywhere in the skin most commonly found in the distal portions of the digits and under fingernails
“Patient that is very tough that is crying in pain over this dot under fingernail” = glomus tumor
Glomus Tumor (Glomangioma) Characteristics
Round, slightly elevated, red-blue
Firm nodules (<1 cm in diameter)
Aggregates, nests, and masses of specialized glomus cells
Branching vascular channels
Microscopically: nice round nodule, but made up of specialized purple glomus cells
Vascular Ectasias: Nevus Flammeus
Group of abnormally prominent capillaries, venules and arterioles that creates a focal red lesion usually in skin or mucous membranes
Nevus Flammeus:
“Birthmark”
Most common form of ectasia
Head or neck; light pink to deep purple
Vascular dilation of blood vessels in dermis
Doesn’t grow with child, stays the same size
Vascular Ectasias: Port Wine Stain
Port wine stain- special form of nevus flammeus that grows with child
Thickens skin surface
Distribution of the trigeminal nerve or occasionally associated with Sturge-Weber syndrome AKA encephalotrigeminal angiomatosis
Rare congenital disorder
Associations:
Venous angiomatous masses in cortical leptomeninges
Ipsilateral facial port wine nevi
Mental retardation, seizures, hemiplegia
Spider Telangiectasia
Focal network of subcutaneous small arteries or arterioles
Arranged in a radial fashion around a central core
Non-neoplastic vascular lesion
Blanches when pressure is applied to its center
Face, neck, or upper chest
Pregnant women or patients with cirrhosis from alcoholism
Hereditary Hemorrhagic Telangiectasia (Osler-Weber-Rendu Disease)
Autosomal dominant disorder
Multiple aneurysmal telangiectasias
Skin and oral mucous membranes, respiratory, GI, urinary tracts
Present from birth
Lesions rupture (occasional): serious epistaxis (nosebleeds), GI bleed, or hematuria
Bacillary Angiomatosis
Vascular proliferation
Opportunistic infection in immunocompromised individuals
Lesions involve skin, bone, brain, other organs
Infection with gram-negative bacilli of the Bartonella family:
1. Bartonella henselae (cat-scratch disease)
2. B. quintana (“trench fever“)
Bacillary Angiomatosis: Characteristics
Skin lesions: red papules and nodules and rounded subcutaneous masses
Capillary proliferation with epithelioid endothelial cells
Nuclear atypia and mitotic figures
Lesions contain neutrophils, nuclear dust, and bacteria
Diagnosis: polymerase chain reaction (PCR)
Treatment: Macrolide antibiotics (erythromycin)
Kaposi Sarcoma
Common in AIDS patients
Four forms of the disease:
- Chronic KS AKA classic or European KS
- Lymphadenopathic KS AKA African or endemic KS
- Transplant-associated KS
- AIDS-associated (epidemic) KS
Chronic Kaposi Sarcoma/European KS
Older men of Eastern European (Ashkenazi Jews) or Mediterranean descent
Can see with underlying malignancy; not HIV
Multiple red to purple skin plaques or nodules
Distal lower extremities
Increase in size and number; spread proximally
Locally persistent; asymptomatic
Remain localized to skin and subcutaneous tissue
Lymphadenopathic KS/ African or Endemic KS
Same geographic distribution as Burkitt lymphoma
Prevalent among South African Bantu children
NOT associated with HIV
Skin lesions are sparse
Lymphadenopathy
Extremely aggressive
Transplant-Associated KS
Solid-organ transplantation on long-term immunosuppression
Aggressive (even fatal)
Nodal, mucosal, and visceral involvement
Cutaneous lesions may be absent
Lesions occasionally regress when immunosuppressive therapy is reduced, which risks organ rejection
AIDS-Associated (Epidemic) KS
Originally found in 1/3rd of AIDS patients
Male homosexuals
Regimens of antiretroviral therapy: incidence is less than 1%
Lymph nodes or viscera
Disseminates/spreads widely early in disease
Pathogenesis of Kaposi Sarcoma
Human herpesvirus-8 (HHV-8)
KS-associated herpesvirus (KSHV)
Member of the γ-herpesvirus subfamily
Transmitted sexually and nonsexual routes (? Saliva)
Kaposi Sarcoma: Three Stages
- Patch
- Plaque
- Nodule
Kaposi Sarcoma: Stage 1
Patch
Red to purple macules
Confined to the distal lower extremities
Dilated irregular endothelial cell-lined vascular spaces
Interspersed lymphocytes, plasma cells, and macrophages
Kaposi Sarcoma: Stage 2
Plaque
More purple than red
Over time, spread proximally
Larger, violaceous, raised
Dermal accumulations of dilated, jagged vascular channels
Lined and surrounded by plump spindle cells
Extravasated red cells, hemosiderin-laden macrophages, and other mononuclear inflammatory cells
Kaposi Sarcoma: Stage 3
Nodule
Distinctly neoplastic
Sheets of plump, proliferating spindle cells
Dermis or subcutaneous tissues
Small vessels and slit-like spaces: contain red cells
More marked hemorrhage, hemosiderin pigment, and mononuclear inflammation
Mitotic figures are common
Heralds nodal and visceral involvement
African and AIDS-associated variants
Hemangioendothelioma
Wide spectrum of vascular neoplasms Epithelioid hemangioendothelioma Vascular tumor of adults Around medium-sized and large veins Plump and cuboidal tumor cells Inconspicuous well-defined vascular channels
Angiosarcoma
Malignant endothelial neoplasms
Varying histology: well-differentiated tumors (hemangiosarcoma) and anaplastic lesions
Older adults–more commonly affected
Skin, soft tissue, breast, and liver
Hepatic Angiosarcoma
Associated with carcinogen exposures:
1. Arsenic (arsenical pesticides)
2. Thorotrast- radioactive contrast agent formerly used for radiologic imaging
3. Polyvinyl chloride (PVC)
Long latent periods between initial exposure and tumor development
Angiosarcoma: Setting of Lymphedema
Setting of lymphedema then develop angiosarcoma
Ipsilateral upper extremity
Several years after radical mastectomy with lymph node resection
Tumor arises from lymphatic vessels (lymphangiosarcoma)
Angiosarcoma Characteristics
Small, sharply demarcated, asymptomatic, red nodules
Large, fleshy masses of red-tan to gray-white tissue
Margins blend with surrounding structures
Central areas of necrosis and hemorrhage
Malignant tumor that forms vessels = looks like little red nodules and see it when hemorrhage
See where highly vascularized like the heart
Hard to delineate malignant tissue from normal tissue because no capsule
Angiosarcoma: Microscopic Evaluation
Plump, anaplastic endothelial cells producing vascular channels
Wildly undifferentiated tumors
Solid spindle cell appearance and without definite blood vessels
CD31 or von Willebrand factor
Locally invasive; metastasize readily
Aggressive tumors; 5-year survival rates approaching 30%
Hemangiopericytoma
Rare neoplasm
Derived from pericytes-myofibroblast-like cells arranged around capillaries and venules
Slowly enlarging, painless masses
Most common in lower extremities (thigh) and retroperitoneum
Numerous branching capillary channels
Gaping sinusoidal spaces enclosed within nests of spindle-shaped to round cells
Recur after excision: about half will metastasize hematogenously to lungs, bone, or liver
