Page 267 - Concise Pathology for Exam Preparation ( PDFDrive )

252 SECTION II Diseases of Organ Systems

(e) Sections show a poorly defined unencapsulated lesion, composed of large cavernous
vascular spaces separated by scant connective tissue stroma.

Q. Describe the clinicopathological features of lymphangiomas.
Ans. Lymphangioma is a benign lymphatic counterpart of haemangioma. It is of two
types:
1. Capillary lymphangioma (also called lymphangiomacircumscriptum)
(a) It is millimetres to centimetres in diameter.
(b) Tends to occur subcutaneously in head and neck region and axilla.
(c) Is distinguished from capillary channels by absence of blood cells.
(d) Lobulated but unencapsulated aggregates of thin-walled lymphatics, separated by
scant connective tissue stroma comprises the lesion.
2. Cavernous lymphangioma (also called cystic hygroma)
(a) Occurs in children in neck and axilla and rarely retroperitoneal region
(b) Histopathology shows massively dilated cystic lymphatic spaces lined by endothe-
lial cells and separated by connective tissue stroma that often contains lymphoid
aggregates.
(c) Margins not well-defined and therefore difficult to remove
Q. Describe the clinicopathological features of glomus tumour.

Ans. Glomus tumour (glomangioma) is an exquisitely painful tumour arising from
modified smooth muscle cells of the glomus body (a specialized arteriovenous anastomosis
involved in thermoregulation).
• Manifests as a small (,1 cm in diameter), red-blue firm nodule usually located in the
distal portion of digits.
• Histopathology shows aggregates and nests of specialized glomus cells (small round to
oval with scanty cytoplasm) lying in connective tissue stroma containing branching
vascular structures.

Q. Enumerate the intermediate grade (borderline or low-grade
malignant) vascular tumours and write briefly about them.
Ans. Intermediate grade vascular neoplasms include
1. Kaposi sarcoma (KS): It was first described by Kaposi in 1872 and is frequently as-
sociated with AIDS. There are four known forms of the disease:
(a) Chronic/Classic/European KS
(i) Mostly affects older men of Eastern European or Mediterranean descent
(ii) Not associated with HIV
(iii) Presents with multiple red to purple skin plaques or nodules on extremities
(iv) Viscera and mucosa are involved in 10% cases
(b) Lymphadenopathic/African/Endemic KS
(i) Particularly prevalent among young Bantu children of South Africa
(ii) Presents with localized or generalized lymphadenopathy
(iii) Disease course is aggressive and there is a strong association with AIDS
(c) Transplant (immunosuppression)-associated KS
(i) Occurs several months to a few years posttransplant in patients receiving high
doses of chemotherapy
(ii) Aggressive; involves lymph nodes, mucosa and visceral organs (usually fatal)
(iii) Skin lesions may be absent
(d) AIDS-associated KS
(i) KS is the most common AIDS-associated cancer in the United States.
(ii) Involvement of lymph nodes and the gut and wide and early dissemination
is the hallmark of the disease.
(iii) Most patients, however succumb to AIDS-associated opportunistic infections
rather than consequences of KS.

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