20 - 122: LIPOGENIC NEOPLASM

Question 1

It is characterized by a diffused overgrowth of mature adipose tissue infiltrating through preexisting structures.

Answer 1

Lipomatosis

Question 2

It is a growing mass with predilection of the hand and it is a rare lesion seen in infants and children.

Answer 2

Lipomatosis of the nerve

Question 3

MC nerve involved in Lipomatosis of the nerve

Answer 3

Median nerve

Followed by the ulnar nerve

Question 4

It represents a high-grade sarcoma containing a variable number of pleomorphic fibroblasts and it usually shows a predilection for the extremities of adults.

Answer 4

Pleomorphic liposarcoma

Question 5

Benign neoplasm of brown fat

Answer 5

Hibernoma

Question 6

It is a very rare benign mesenchymal neoplasm of deep soft tissue composed of an irregular mixture of mature adipocytes and smooth muscle cells.

Answer 6

Myolipoma

Question 7

It presents as papules, plaques, or solitary lesions with a predilection for the buttocks, upper posterior thighs and lumbar back. In histopathology, it is defined as ill-defined lesions composed of mature adipose tissue that replaces the dermis.

Answer 7

Nevus lipomatosis superficialis

Question 8

It presents as painful and tender subcutaneous lesions that occur predominantly at the forearm followed by the trunk, upper arm, and legs.

Answer 8

Angiolipoma

Question 9

It often presents as asymptomatic, often long standing, mobile tumor in the subcutaneous tissue. Histologically, the characteristic feature of this tumor is the additional presence of multinucleated giant cells with radially arranged nuclei - floret-like giant cells.

Answer 9

Pleomorphic lipoma

Question 10

Painless, slow growing lesions predominantly in infants or children characterized as infiltrative growth that often extends into deeper structures.

Answer 10

Lipoblastomatosis

Question 11

most common benign mesenchymal neoplasm

Answer 11

Lipoma

Question 12

Lipomas may be seen as a manifestation of what syndromes?

Answer 12

• Gardner syndrome - Familial adenomatous polyposis, desmofibromatosis, lipomas, osteomas, cysts
• Bannayan (Bannayan-Riley-Ruvalcaba Syndrome) syndrome: Macrocephaly, lipomas, lymphangiomas, hamartomas, intestinal polyposis, lentigines

Question 13

Hamartomas, trichilemmomas, lipomas, oral papillomas, palmoplantar keratoses

Answer 13

Cowden syndrome

Question 14

This gene plays an important role in the pathogenesis of lipoma

Answer 14

HMGA2 gene

Question 15

Lipomatosis of nerve is a growing mass with a predilection for the

Answer 15

Hand

Question 16

Lipomatosis of nerve is a rare lesion seen in what age group

Answer 16

Infants and children

Question 17

Answer 17

Lipomatosis of nerve. A, Epineural infiltration of lipogenic cells and collagenous fibrous tissue separating nerve bundles. B, Note the perineural fibrosis.

Question 18

composed of an irregular mixture of mature adipocytes and smooth muscle cells.

Answer 18

MYOLIPOMA

Question 19

The most common anatomic site for hibernoma

Answer 19

thigh followed by the trunk, the chest wall, the shoulder area, the upper extremity, and the head and neck area

Question 20

tumor cells stain positively for S-100 protein and for ___________, a protein unique to brown adipocyte mitochondria

Answer 20

uncoupling protein