IHC

Factor XIIIa

Marks dermal dendrocytes and is used for histiocytic phenotyping. Factor XIIIa also stains capillary hemangiomas and certain central nervous system tumors. In combination with CD34, it helps differentiate dermatofibroma (Factor XIIIa positive) from dermatofibrosarcoma protuberans (CD34 positive).

Synonyms

Factor 13, F13a

Full Description

Marks dermal dendrocytes and is used for histiocytic phenotyping. Factor XIIIa also stains capillary hemangiomas and certain central nervous system tumors. In combination with CD34, it helps differentiate dermatofibroma (Factor XIIIa positive) from dermatofibrosarcoma protuberans (CD34 positive).

Methodology

IHC

Specimen Requirements

Tissue Block: Formalin-fixed, paraffin-embedded (FFPE) tumor block preferred. Unstained Slides: Recommended 2 charged slides per stain requested (minimum of 1 slide per stain), baked or unbaked. Fixation: Tissue must be fixed in 10% neutral buffered formalin for 6–72 hours.

Storage and Transportation

Use cold pack for transport. Make sure cold pack is not in direct contact with specimen.

Turnaround Time

24 Hrs

CPT Codes

88342x1 or 88341x1