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What is HMB 45 is a tumor marker for and explain in detail?
Malignant melanoma expresses HMB45 ,S-100 and vimentin 
HMB 45 is present in melanosome and is more specific 
S-100 is more sensitive but is non specific (also present in LAngerhan's cell histiocytosis, neural tumors and sarcomas like Liposarcoma and Chondrosarcoma)