Case Report: Giant adult rhabdomyoma of the parapharyngeal space: diagnostic and surgical pitfalls

Background Adult-type extracardiac rhabdomyoma is a rare benign skeletal-muscle neoplasm that most often arises in the head and neck but is exceptional in the parapharyngeal space, where it may mimic salivary or neurogenic tumours. Case presentation: A 67-year-old man presented with a 6-month history of progressive dysphagia, globus sensation, and mild hoarseness. Computed tomography and magnetic resonance imaging demonstrated an approximately 9-cm, well-circumscribed right parapharyngeal mass with relatively homogeneous internal characteristics and mild-to-moderate enhancement. Because direct glottic exposure was inadequate, tracheotomy-assisted airway management preceded complete excision through a right lateral transcervical approach. Histopathology showed large polygonal cells with abundant eosinophilic granular cytoplasm. The tumour was positive for desmin and smooth-muscle actin, with focal MyoD1 and myogenin expression, a low Ki-67 labelling index, and negative S-100 staining, supporting adult-type rhabdomyoma. Recovery was uneventful, and magnetic resonance imaging at 6 and 12 months showed no recurrence. Conclusion Adult rhabdomyoma should be considered in the differential diagnosis of a well-circumscribed parapharyngeal mass in an older adult. Integrated radiological and pathological assessment, careful airway planning, complete conservative excision, and long-term surveillance are central to management.