ABSTRACT
BACKGROUND: Hyalinizing clear cell carcinoma (HCCC) is a rare low-grade malignant tumor affecting the minor salivary glands; nasopharyngeal involvement is uncommon. METHODS AND RESULTS: A 38-year-old male patient presented with a 3.2 × 4.5 × 4.4 cm expansile mass obliterating the lumen of the nasopharynx and extending into the left nasal cavity. Histopathologically, the tumor was characterized by clear round to polygonal epithelial cells arranged in anastomosing trabeculae and solid nests. The stroma consisted of fibromyxoid connective tissue with areas of intense hyalinization and desmoplasia. Immunohistochemically, strong and diffuse reactivity for AE1/AE3, CK5/6, and p63 was observed. EWSR1 gene rearrangement was confirmed by fluorescence in situ hybridization. The diagnosis of nasopharyngeal HCCC was rendered. Surgical excision was performed along with adjuvant radiotherapy and chemotherapy. CONCLUSIONS: HCCC generally demonstrates good prognosis with low metastatic potential. Identification of EWSR1 gene disruption is usefulin discerning HCCC from other neoplasms with overlapping microscopic features.
Subject(s)
Adenocarcinoma, Clear Cell/genetics , Adenocarcinoma, Clear Cell/pathology , Calmodulin-Binding Proteins/genetics , Nasopharyngeal Neoplasms/genetics , Nasopharyngeal Neoplasms/pathology , RNA-Binding Proteins/genetics , Adult , Biomarkers, Tumor/analysis , Carcinoma , Gene Rearrangement , Humans , Hyalin/metabolism , Immunohistochemistry , In Situ Hybridization, Fluorescence , Male , Nasopharyngeal Carcinoma , RNA-Binding Protein EWSABSTRACT
We report on a black male patient from Central America with amelogenesis imperfecta, rough hypoplastic type, dental follicular hamartomas, and gingival hyperplasia. Although previous reports have described this association of amelogenesis imperfecta with hyperplastic follicular hamartomas or central odontogenic fibroma-like lesions in blacks from South Africa, we have noticed non-black patients in the literature with similar findings.