Description
Why It’s Done:
This test is performed to:
• Diagnose melanoma, especially when the tumor’s origin is unclear.
• Differentiate melanoma from non-melanocytic tumors, such as carcinomas or sarcomas.
• Confirm metastasis of a known melanoma to another site (e.g., lymph node, internal organ).
• Assist in treatment planning by accurately identifying the tumor type.
S-100 is highly sensitive, and HMB-45 adds specificity, making the combination valuable in identifying melanoma cells.
Preparation:
• No special preparation is needed from the patient.
• The test is conducted on a tissue sample obtained via biopsy or surgical excision.
• If you are undergoing a biopsy, your healthcare provider may give instructions regarding:
o Fasting (if sedation is required)
o Medication management
o Post-biopsy care and transportation
Always follow your provider’s specific pre-procedure guidelines.
