[Histonet] Mart-1/Melan-A as a stain for melanoma sentinel nodes

[Barnhart, Tammy]

We are having some debate about which marker to use for our melanoma
sentinel node screens.  We have been using Mart-1, but recently had a case
where we think mast cells were stained.  We can find no literature that
indicates that Mart-1 will stain mast cells.  We use Lab Vision's
Mart-1/Melan-a AB-3 (clone M27C10+M2-9e3).  We ran a Mast Cell tryptase to
see what stained, and all the cells that stained with the Mart-1 stained
plus a bunch of others.  So if the Mart-1 is staining mast cells, it is only
staining a subset of them.  We really think that these are mast cells and
not melanoma, but would like to see some literature to support this.  So two
questions: 1) What are people using as a screening antibody and 2) Does
anyone have a reference that indicates that this antibody will stain mast
cells.  Thanks in advance for your help.

Tammy Barnhart, BS, HTL(ASCP)
Anatomic Pathology Supervisor
St. Alexius Medical Center
Bismarck, ND