Introduction: Primary squamous cell carcinoma (SCC) of the Eustachian tube (ET) is an extremely rare and difficult to diagnose because of its deep anatomical location and nonspecific otologic symptoms. In addition, routine temporal bone computed tomography (CT) does not always visualize the entire ET, which can contribute to diagnostic delay. Case Report: A 53-year-old male presented with a two-year history of unilateral ear fullness and progressive conductive hearing loss without otorrhea, otalgia, or ear bleeding. He was initially treated for otitis media with effusion (OME) with tympanostomy tube placement and subsequently underwent tympanoplasty with canal wall-up mastoidectomy for suspected cholesteatoma at a tertiary care hospital. Histopathological examination of granulation tissue initially revealed inverted papilloma (IP), but pathological review at our hospital led to a diagnosis of SCC. Endoscopic examination revealed a mass at the pharyngeal orifice of the ET, and subsequent imaging studies demonstrated a tumor extending along the course of the ET. Definitive chemoradiotherapy resulted in complete remission, and the patient remains disease-free five years after treatment. Conclusion: This case illustrates the diagnostic difficulty of ET carcinoma presenting as prolonged unilateral OME. When the clinical course is atypical or prolonged, disease beyond the middle ear should be considered, and assessment of the ET and nasopharynx with appropriate imaging and endoscopic evaluation may help prevent delayed diagnosis.
Asamori et al. (Thu,) studied this question.