Cervical schwannomas are rare benign tumors that can mimic thyroid tumors, especially when located adjacent to the thyroid gland. The preoperative diagnosis is often difficult to establish due to nonspecific and inconclusive findings on imaging and fine-needle aspiration cytology. This case report describes an older woman who presented with a gradually enlarging cervical mass associated with hoarseness. This was initially diagnosed as an adenomatous thyroid nodule during routine follow-up. However, the patient developed progressive neck swelling accompanied by hoarseness and dyspnea, and marked tumor enlargement was noted. Computed tomography revealed a large heterogeneous mass compressing the trachea and esophagus. Laryngoscopy demonstrated left vocal cord paralysis, suggesting recurrent laryngeal nerve involvement. The tumor was surgically resected, and left thyroid lobectomy was performed. Histopathological examination revealed proliferation of spindle-shaped cells with S-100 positivity, consistent with schwannoma. Accordingly, cervical schwannoma should be considered in the differential diagnosis of thyroid-adjacent neck masses. • Cervical schwannoma mimicking a thyroid tumor adjacent to the gland • Preoperative diagnosis is difficult with US and FNAC alone • Vocal cord paralysis suggests recurrent laryngeal nerve origin • CT/MRI and laryngoscopy are key for accurate preoperative assessment • Surgical resection confirmed S-100–positive schwannoma
Matsukawa et al. (2026) studied this question.