SOX10 and carcinoma: SOX-10 immunohistochemistry (IHC) is commonly positive in melanoma [3,4], but has also been described in benign adnexal skin tumors such as cylindroma and spiradenoma (uniformly positive) [5]; in schwannoma [4]; in tumors of myoepithelial origin [4]; and in a subset of carcinomas such as bladder [6], breast [7], gastric [8], hepatocellular [9], nasopharyngeal [10], ovarian [11], prostate [12], as well as salivary gland tumors [13,14], and squamous cell carcinoma of head and neck [4].