Fibroepithelial and Stromal Lesions

Question 1

From where do fibroepithelial lesions arise?

Answer 1

Intralobular stroma. Contain both stromal and epithelial elements.

Question 2

What is a fibroadenoma?

Answer 2

Common, mobile, painless, well-defined breast lump composed of epithelial and stromal components

Question 3

What are the two components of a fibroadenoma?

Answer 3

Stroma and epithelium

Question 4

What are the two patterns of fibroadenomas?

Answer 4

Intracanalicular and pericanalicular

Question 5

Elongated epithelial duct structures are situated within a loose myxoid stroma. Dx?

Answer 5

Fibroadenoma

Question 6

Stroma shows hypercellularity, although mitoses and cellular atypia are not present. Epithelial hyperplasia of usual type is present in the glands. This was found in an adolescent. Dx?

Answer 6

Juvenille Fibroadenoma

Question 7

Uscopic fronds of hypercellular stroma lead to formation of leaf-like structures, which project into cystic spaces. What is the Dx?

Answer 7

Phyllodes Tumor

Question 8

Where are stromal components of phyllodes tumors seen?

Answer 8

Only in metastases

Question 9

From what do stromal lesions arise?

Answer 9

Nonspecialized interlobular stroma

Question 10

Anastomosing spaces are seen in dense collagenous stroma. Myofibroblasts are distriuted singly at the margins of the spaces. Dx?

Answer 10

Pseudoangiomatous Stromal Hyperplasia

Question 11

Interlacing bundles of spindle cells, without nuclear atypia, are present with focal bands of collagen. Dx?

Answer 11

Fibromatosis

Question 12

What mutation leads to Fibromatosis?

Answer 12

Mutations in the adenomatous polyposis coli (APC) gene