Factor XIIIa

Stains
Factor XIIIa

Author: Nat Pernick, M.D.

Topic Completed: 1 August 2012

Revised: 5 March 2019

Copyright: 2003-2018, PathologyOutlines.com, Inc.

PubMed Search: Factor XIIIa

Page views in 2018: 4,686

Page views in 2019 to date: 4,925

Table of Contents

Cite this page: Pernick N. Factor XIIIa. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/stainsfactorxiiia.html. Accessed November 19th, 2019.

Definition / general

Fibrohistiocytic marker; note that peritumoral cells may also exhibit Factor XIIIa staining
Also active form of factor XIII, an enzyme of coagulation system that crosslinks fibrin (Wikipedia: Factor XIII [Accessed 2 August 2018])

Uses by pathologists

Marker of fibrohistiocytic proliferations
Marker of dermal dencrocytes
Differentiate dermatofibrosarcoma protuberans (CD34+, D2-40-, Factor XIIIa-) from dermatofibroma (CD34-, Factor XIIIa+, D2-40+)

Microscopic (histologic) images

Images hosted on PathOut server:

Epithelioid fibrous histiocytoma

Images hosted on other servers:

Atypical fibroxanthoma

Positive staining - normal

Dermal dendrocytes

Positive staining - disease

Soft tissue: benign fibrous histiocytoma and variants, malignant fibrous histiocytoma
Also calcifying fibrous tumor (Mod Pathol 2001;14:784), verruciform xanthoma
Also atypical fibroxanthoma (focal), hemangiopericytoma (scattered), myofibroblastoma in lymph nodes (variable), pleomorphic hyalinizing angiectatic tumor (focal), storiform collagenoma (scattered)
Cervix: aggressive angiomyxoma
CNS: Erdheim-Chester disease

Negative staining

Dermatofibrosarcoma protuberans (usually), Langerhans cell histiocytosis
Solitary fibrous tumor (Int J Gynecol Pathol 2010;29:189)