Methodology
Immunohistochemistry (IHC)
Test Description
Melan A (Mart1, Melanoma Antigen Recognized by T-cells 1), is a differentiation antigen that is expressed in melanocytes, most melanomas. Melan A recognizes a subcellular fraction found in melanosomes. Melan A is a useful addition to melanoma panels since it is specific for melanocytic lesions. Both HMB 45 and Melan A are co-expressed in the majority of melanomas, as well as uniquely expressed in certain cases. Melan A antibody, A103 clone labels the tumor cells of a subset of adrenocortical carcinomas and sex cord tumors of the gonads.
Specimen Requirements
  • A formalin-fixed, paraffin-embedded (FFPE) tissue block is preferred specimen type
  • or
  • One (1) unbaked, unstained slide for H&E staining (required) and two to three (2-3) positively charged unstained slides (all cut at 4-5 microns) for each test/antibody ordered
  • Block and slide identifiers should be clearly written and match exactly with the specimen ID and specimen labeling as noted on the requisition.
Storage and Transportation
Use cold pack for transport. Make sure cold pack is not in direct contact with specimen.
CPT Code(s)*
88342 x 1 or 88341 x 1
Turnaround Time
24 hours
Level of Service
Stain Only

*The CPT codes provided with our test descriptions are based on AMA guidelines and are for informational purposes only. Correct CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed.