Premium
The Role of P‐75 NGF‐R in the Diagnosis of Desmoplastic Melanoma
Author(s) -
Ghosn S.,
Radfar A.,
Stefanato C.M.,
Bhawan J.
Publication year - 2005
Publication title -
journal of cutaneous pathology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.597
H-Index - 75
eISSN - 1600-0560
pISSN - 0303-6987
DOI - 10.1111/j.0303-6987.2005.320cc.x
Subject(s) - immunohistochemistry , melanoma , stain , pathology , staining , neural crest , melanin , nerve growth factor , positive staining , biology , medicine , cancer research , receptor , microbiology and biotechnology , embryo , genetics
The histologic diagnosis of desmoplastic melanoma is challenging, particularly when the overlying junctional component is absent and when the spindle cells lack melanin pigment. In these instances, the importance of immunohistochemistry cannot be overemphasized. S‐100 protein, with a sensitivity approaching 90%, is the primary immunohistochemical stain used for this purpose. HMB‐45, although a more specific marker for melanocytes, is often negative in these cases. A marker of schwannian differentiation, p‐75 NGF‐R has been shown to be a useful confirmatory marker for desmoplastic and neurotropic melanoma, with staining intensity comparable to or better than S‐100 protein. We report two cases of desmoplastic melanoma which stained focally and weakly with S‐100 protein in comparison with the stronger staining of p‐75 NGF‐R. In both cases, S‐100 staining could have been missed or interpreted as non‐confirmatory, thus misguiding the diagnosis. We therefore suggest that p‐75 NGF‐R be a complementary marker to S‐100 protein in differentiating desmoplastic melanoma from other non‐neural crest‐derived spindle cell tumors.