Question
Below given is a histopathological image of a blood vessel/lymph tumor.Regarding this pathology,which of the following statements is true?
A. Common in Uganda in Africa
B. Associated with recipients of renal transplants
C. Seen in about 30% cases of AIDS
D. All of the above
Show Answer
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Correct Answer » D Explanation |
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Ans:D. All of the Above.
Image shows:Kaposi’s sarcoma in late nodular stage. There are slit-like blood-filled vascular spaces. Between them are present bands of plump spindle-shaped tumour cells.
Kaposi’s Sarcoma
- Kaposi’s sarcoma is a malignant angiomatous tumour .
CLASSIFICATION.
1. Classic (European) Kaposi’s sarcoma.
- It is more common in men over 60 years of age of Eastern European descent.
- The disease is slow growing and appears as multiple, small, purple, dome-shaped nodules or plaques in the skin, especially on the legs.
- Involvement of visceral organs occurs in about 10% cases after many years.
2. African (Endemic) Kaposi’s sarcoma.
- This form is common in equatorial Africa.
- It is so common in Uganda that it comprises 9% of all malignant tumours in men.
- It is found in younger age, especially in boys and in young men and has a more aggressive course than the classic form.
- The disease begins in the skin but grows rapidly to involve other tissues, especially lymph nodes and the gut.
3. Epidemic (AIDS-associated) Kaposi’s sarcoma.
- This form is seen in about 30% cases of AIDS, especially in young male homosexuals than the other high-risk groups.
- The cutaneous lesions are not localised to lower legs but are more extensively distributed involving mucous membranes, lymph nodes and internal organs early in the course of disease.
4. Kaposi’s sarcoma in renal transplant cases.
- This form is associated with recipients of renal transplants who have been administered immunosuppressive therapy for a long time.
- The lesions may be localised to the skin or may have widespread systemic involvement.
PATHOGENESIS.
- It is an opportunistic neoplasm in immunosuppressed patients which has excessive proliferation of spindle cells of vascular origin having features of both endothelium and smooth muscle cells:
- Epidemiological studies have suggested a viral association implicating HIV and human herpesvirus 8 (HSV 8, also called Kaposi’s sarcoma-associated herpesvirus or KSHV).
- Occurrence of Kaposi’s sarcoma involves interplay of HIV-1 infection, HHV-8 infection, activation of the immune system and secretion of cytokines (IL-6, TNF-α, GM-CSF, basic fibroblast factor, and oncostain M).
- Defective immunoregulation plays a role in its pathogenesis is further substantiated by observation of second malignancy (e.g. leukaemia, lymphoma and myeloma) in about one-third of patients with Kaposi’s sarcoma.
MORPHOLOGIC FEATURES.
- Grossly, the lesions in the skin, gut and other organs form prominent, irregular, purple, dome-shaped plaques or nodules.
- Histologically, the changes are nonspecific in the early patch stage and more characteristic in the late nodular stage.
- Early patch stage: There are irregular vascular spaces separated by interstitial inflammatory cells and extravasated blood and haemosiderin.
- Late nodular stage: There are slit-like vascular spaces containing red blood cells and separated by spindleshaped, plump tumour cells. These spindle-shaped tumour cells are probably of endothelial origin.
