Nasopharyngeal Tuberculosis with Regional Lymphadenopathy Mimicking Thyroid Cancer with Cervical Lymph Node Metastasis Recognized by F-18 FDG PET/CT: A Case Report

摘要

Nasopharyngeal tuberculosis demonstrated by Fluorine-18 fluorodeoxyglucose positron emission tomography and computed tomography (F-18 FDG PET/CT) has scarcely been reported. We report a patient with this disease initially manifested as having thyroid cancer with cervical lymph node metastasis, but had no cytologic evidence after twice tissue aspiration. F-18 FDG PET/CT showed abnormal hypermetabolism in the nasopharynx and led to correct diagnosis and effective treatment. F-18 FDG PET/CT may be a valuable modality to detect the primary lesions in patients presenting with unexplained regional lymphadenopathy. Tuberculosis (TB), though best known in the form of intrapulmonary infection, may involve any organ system. According to the latest control report of TB, 4.5% of all new notified patients in Taiwan were extrapulmonary in the year of 2011 [1]. Among these extrapulmonary subtypes, TB primarily detected in the nasopharynx is one of the rarest and has seldom been reported, even in endemic areas [2-4]. The infrequency and the often clinically non-specific manifestations of this disease sometimes preclude nasopharyngeal TB from being considered. Here we report a female patient who presented with prominent bilateral cervical lymphadenopathy and negative finding in nasopharyngoscopy. Computed tomography (CT) of head and neck was unhelpful in the attempt to discover underlying causes. Fluorine-18 fluorodeoxyglucose positron emission tomography and computed tomography (F-18 FDG PET/CT) first pointed out abnormality in the nasopharynx, but the infectious nature was not revealed until histopathological study was performed.