SOX10 Expression in Malignant Melanoma, Carcinoma, and Normal Tissues

Abstract

Sry-related HMg-Box gene 10 (SOX10) is a nuclear transcription factor that plays an important role in melanocytic cell differentiation. It has been shown to be a sensitive marker of melanoma including spindle and desmoplastic subtypes. We assessed its frequency of expression in melanoma, carcinoma, benign nevi, and non-neoplastic tissues with routine immunohistochemistry for SOX10. The 109 primary melanoma included 49 epithelioid, 19 spindle cell, 22 desmoplastic, and 19 mixed spindle cell/desmoplastic melanoma. All primary, except 8 desmoplastic melanoma, and 11 metastatic melanoma were strongly and diffusely nuclear SOX10-positive. Six desmoplastic melanoma had ≤10% cells positive, and 2 were <50% positive, all of 3+ intensity. Eighteen of 149 (12%) breast carcinoma were SOX10-positive. All 24 ovarian, 23 endometrial, 26 lung, and 25 colon carcinoma were SOX10-negative. All 43 benign nevi, 18 dysplastic nevi, 68 non-neoplastic and benign skins, and all 56 non-neoplastic breast tissue were SOX10-positive. The sensitivity and specificity for SOX10 in the diagnosis of melanoma are 1.0 and 0.93, respectively; the positive and negative predictive values are 0.87 and 1.0, respectively. SOX10 is a sensitive, specific marker for melanoma. As benign nevi also express SOX10, it cannot be used to differentiate between benign and malignant pigmented skin lesions. Only a small number of breast carcinoma (12%), and breast lobules, express SOX10; no carcinoma of the ovary, endometrium, lung, or colon expressed SOX10.

A diagnostic algorithm to distinguish desmoplastic from spindle cell melanoma

“…Desmoplastic melanoma is currently defined as a subtype of spindle cell melanoma; 1 however, the term spindle cell melanoma can either serve as an umbrella term for the spindle cell and desmoplastic melanoma category, might be applied as a descriptive diagnosis for a conventional melanoma with prominent spindle cells, or-as applied here-may refer to a specific entity that is typically amelanotic, contains o10% collagen fibrils, shows immunophenotypic differences to conventional melanoma, 18,[24][25][26] and typically presents as a thicker lesion or in advanced stages. Further, BRAF mutations occur with different prevalence in spindle cell melanoma.…”

A Newly Developed Mouse Monoclonal SOX10 Antibody Is a Highly Sensitive and Specific Marker for Malignant Melanoma, Including Spindle Cell and Desmoplastic Melanomas

“…1,[11][12][13][14][15] In our study, 115 of 119 primary cutaneous melanomas (96.6%) stained with SOX10. This compares well with the study by Nonaka et al, 7 where SOX10 nuclear expression was found in 76 of 78 melanomas (97%).…”

“…3,5 SOX10 is also present in benign tumors, such as melanocytic nevi, schwannomas, and neurofibromas. [1][2][3][5][6][7] SOX10 is highly expressed in desmoplastic melanomas (DMs) and spindle cell melanomas (SCMs).…”

“…2015;139:530-536; doi: 10.5858/ arpa.2014-0077-OA) S ry-related HMG-Box gene 10 (SOX10) protein is a human transcription factor important for neural crest, peripheral nervous system, and melanocytic cell development. [1][2][3][4] The SOX10 nuclear protein has been shown to be widely expressed in normal human tissues, including melanocytes, Schwann cells, breast and salivary gland myoepithelial cells, and oligodendroglial cells. [1][2][3]5,6 It is also expressed in malignant tumors, such as melanoma, malignant peripheral nerve sheath tumors, and a subset of breast carcinomas.…”

“…To date, most publications have used an immunohistochemistry method using a research useonly goat polyclonal SOX10. 1,7,[11][12][13][14][15][16][17][18] We herein describe the development of a new mouse monoclonal SOX10 hybridoma (BC34) and evaluate its sensitivity and specificity in normal and neoplastic tissues, with an emphasis on melanoma and its subtypes.…”