3.2.3. Vascular Pathology 3 of 3 Flashcards
What is and where do we find simple or capillary lymphangiomas?
Simple (capillary) lymphangioma
pedunculated lesions up to 1-2 cm in diameter
predominantly on the head, neck, and axilla
When do we see, how do they present and what are cavernous lymphangiomas (cystic hygromas)?
massively dilated lymphatic spaces lined by endothelial cells & separated by intervening connective tissue stroma containing lymphoid aggregates
margins are indistinct and unencapsulated; resection is difficult
CL of the neck are common in Turner syndrome
How do they present and what are Glomus Tumors?
benign but exquisitely painful tumors
arise from modified SM cells of the glomus bodies (involved in thermoregulation)
Morphology of Bacillary Angiomatosis
skin lesions are red papules and nodules or rounded subcutaneous masses
Histology of Bacillary Angiomatosis
Histologically: capillary proliferation with prominent epithelioid endothelial cells exhibiting nuclear atypia and mitoses. Lesions contain stromal neutrophils, nuclear dust, and the causal bacteria.
What cat bacteria is linked to Bacillary Angiomatosis? What conditions are associated with it?
Bartonella henselae: principal reservoir is the domestic cat; causes cat-scratch disease
necrotizing granulomatous disorder of lymph nodes
What causes Kaposi sarcoma?
Kaposi Sarcoma caused by human herpes virus 8 (HHV8) highly associated with AIDS
Who gets Kaposi Sarcoma?
Classic KS: disorder of mediterranean, middle eastern, or eastern european descent (esp. ashkenazic Jews)
How does Kaposi Sarcoma present, and where is it on the body?
multiple red-purple skin plaques or nodules
usually distal, lower extremities
Progress and Treatment for Kaposi?
persistent, but usually asymptomatic and remain localized to skin and subq
treatment: surgical removal
Most common tumor in central Africa
Endemic African Kaposi Sarcoma
How is Endemic African Kaposi Sarcoma different from clasic Kaposi Sarcoma?
usually HIV-seronegative individuals than classic KS
How do we treat Transplant associated Kaposi Sarcoma?
treatment: decrease immunosuppression
How do we treat AIDS associated Kaposi Sarcoma?
treatment: antiretroviral agents to boost immune system
How common of a malignancy is AIDS Associated Kaposi Sarcoma in HIV patients?
most common HIV-related malignancy
What is Hemangioendothelioma?
spectrum of vascular neoplasms with clinical behaviors intermediate between benign, well-differentiated hemangiomas and frankly anaplastic angiosarcomas
How are malignant tumor vasculature conditions different from benign?
Benign tumors typically form obvious vascular channels lined by normal-appearing endothelial cells. Malignant tumors are more often solid and cellular, exhibit cytologic atypia, and lack well-defined vessels
What are angiosarcomas?
Angiosarcoma: malignant endothelial neoplasm that primarily affects older adults
mostly involves skin, soft tissue, breast, and liver
What are Hepatic angiosarcomas? What are they associated with? How mobile are they?
associated with carcinogenic exposures
arsenic, PVC, Thorotrast
locally invasive and can readily metastasize
Morphology of Hepatic Angiosarcomas
cutaneous: deceptively small and asymptomatic red papules or nodules; eventually become large, fleshy masses of red-tan to gray-white tissue with margins blurring imperceptibly into surrounding structures
What do we use to best see Hepatic Angiosarcomas microscopically?
endothelial origin of these tumors can be demonstrated by immunohistochemical staining for CD31 or von Willebrand factor
What are Hemangiopericytomas?
tumors of ACTUAL pericytes are very rare and the vast majority of those previously assigned to this group are derived from other cells (e.g. fibroblasts)
Describe a balloon angio
transiently inflating a balloon catheter to pressures sufficient to rupture an occluding plaque
What are coronary stents?
expandable tubes of metallic mesh to make a larger and more regular lumen. Useful to tack down intimal flaps and dissections and mechanically limits vascular spasm
2 complications of stents
thrombosis
proliferative in-stent restenosis (lumina closes up again); significant number within 6-12 months of stenting
How do drug eluting stents work?
leach antiproliferative drugs into the adjacent walls to prevent SM cell activation
What are vascular grafts?
synthetic or autologous vascular grafts used increasingly to replace damaged vessels or bypass diseased arteries
When do we use large-bore (12-18 mm) synthetic conduits?
function well in high-flow locations (e.g. aorta)
Problem with small-diameter artificial grafts (</= 8 mm dia)
generally fail b/c:
thrombosis
late intimal hyperplasia
Better alternatives to small diameter artificial grafts and how effective are they?
saphenous vein grafts
long-term patency: only 50% at 10 years
internal mammary artery
long-term patency: 90% at 10 years