• Useful stain to confirm or exclude a diagnosis of malignant melanoma (using a single stain)
• Excellent stain to use in attempts at identifying metastatic melanoma to lymph nodes

Submit processed tissue block or tissue section mounted on a charged, unstained slide

Formalin-fixed, paraffin embedded (FFPE) tissue block

Ambient (preferred)

Immunohistochemical staining and microscopic examination

If requested, an interpretive report will be provided

All IHC stains will include a positive control tissue

Specifications:

• Melanoma cocktail is composed of antibodies to Tyrosinase, Mart1, HMB45 (created in our lab using three separate antibodies)

Tyrosinase:

• Highly specific marker for identifying melanoma
• Will not cross react with melanophages
• 100% specific and >80% sensitive for non-spindle cell type melanomas
• 100% specific and 85% sensitive for amelanotic melanomas
• Very specific marker for identifying malignant melanoma in sentinel lymph nodes

HMB45:

• Reacts with most melanomas (approximately 80%)
• Also reacts with benign melanocytes such as in junctional melanocytes, Spitz nevi, and cellular blue nevi

MART-1:

• Expressed in virtually all nevi with the exception of neurotized melanocytes with prominent Schwannian differentiation
• Stains all melanomas with epithelioid or mixed spindle and epithelioid features
• Is more sensitive than HMB45 in identifying desmoplastic melanoma, however is less sensitive than S100 (Mart-1may stain <50% of cells in desmoplastic melanomas)
• Mart-1 can detect a small number of HMB45 negative metastatic melanomas and a rare case of S100 negative metastatic melanoma
• It has virtually the same sensitivity as Melan-A

Staining pattern:

• Pathologist cannot discriminate one marker from another using this cocktail