HMB 45 is a tumor marker for-

HMB-45 is a monoclonal antibody that reacts against an antigen present in melanocytic tumors such as melanomas, and stands for homatropine methylbromide 45. It is used in anatomic pathology as a marker for such tumors. The specific antigen recognized by HMB-45 is now known as Pmel 17. HMB-45 was discovered by Drs. Allen M. Gown and Ahur M. Vogel in 1986. The antibody was generated to an extract of melanoma. It reacts positively against melanocytic tumors but not other tumors, thus demonstrating specificity and sensitivity.