Primary thyroid-like low-grade nasopharyngeal papillary adenocarcinoma in a 11-year-old male patient: The first case report in Indonesia

Abstract

Thyroid-like low-grade nasopharyngeal papillary adenocarcinoma (TL-LGNPPA) until now is a very rare neoplasm, characterized by its similar histopathological appearance to conventional papillary thyroid carcinoma with strong positive thyroid transcription factor-1 (TTF-1) expression. Here we present the first case report of TL-LGNPPA in Indonesia, which occurred in an 11-year-old male patient with chief complaints of epistaxis and nasal obstruction for three months. Rhinoscopy and computed tomography examinations revealed a visible hemorrhagic mass located in nasopharynx suspected as angiofibroma, extending to the bilateral nasal cavity. Histologically, the tumor architecture was dominantly papillary with cuboidal to columnar epithelium. Few tumor cells showed intra-nuclear inclusions. Immunostaining of cytokeratin 7 and thyroid transcription factor-1 showed strong and diffuse positivity, cytokeratin 20 and thyroglobulin exhibited focal positivity, meanwhile PAX-8 was negatively expressed. Ki-67 labeling index was low (1.8%). Real-time PCR analysis showed no BRAF V600E mutation. Thus, clinical, radiological, histopathological, immunohistochemical and molecular examination profiles confirmed the diagnosis of TL-LGNPPA.

Keywords

• Thyroid-like low-grade nasopharyngeal papillary adenocarcinoma
• Thyroid transcription factor-1
• Thyroglobulin
• Nasopharynx