Spindle Cell Lesions

Question 1

It is a breast mass, composed of keloid like material with complex anastomotic spaces that are often empty and have peripherally placed myofibroblasts
Spindle cells (+) CD34, AR, and PR
(-) CK and CD31
Dx?
Pathogenesis?

Answer 1

Pseudoangiomatous stromal hyperplasia (PASH)
Benign breast lesion with aberrant response to hormone to

Question 2

This breast lesion is composed of bland spindle cells composed of fibroblasts and myofibroblasts that are arranged in short haphazardly intersecting fascicles. Interspersed, sick collagen bundles are present.
(+) desmin, CD34, ER, AR, PR
(-) RB1

Answer 2

Myofibroblastoma

Question 3

This tumor is composed of broad, sweeping fascicles of uniform, spindle self, with a small, pale nuclei with pinpoint nucleoli. There is moderate amounts of collagen, and may be slightly myxoid.
(+) nuclear beta catenin
Dx?
Mutation?

Answer 3

Desmoid fibromatosis
FAP (if syndromic), CTNNB1

Question 4

This Lesion is composed of irregularly shaped thin walled vessels with branching and anastomotic growth. The lumen is lined by a single layer of endothelial cells with some hobnail and hyper chromatic features.
(+) vascular markers
(-) MYC overexpression/amplification
Dx?
RF?

Answer 4

Atypical vascular lesiom
Irradiated skin of breast

Question 5

This tomorrow is composed of spindled to plum epithelioid cells lining vascular channels. The nuclei often contain a bullet shaped nucleolus.
(+) vascular markers, high ki67
Dx?
RF?
Molecular?

Answer 5

Angiosarcoma
5 years post radiation
MYC positive in post-radiation angiosarcoma

Question 6

It is a biphasic proliferation of inner ductal cells and outer myoepithelial cells. It may have sebaceous, squamous or apocrine metaplasia.
Dx?
Prognosis

Answer 6

Adenomyoepithelioma
Can de-differentiate into carcinoma (any type)