Not all apneas are obstructive sleep apnea: a case report of a concealed adenoid cystic carcinoma of the larynx

Abstract Background Laryngeal adenoid cystic carcinoma (LACC) is a rare malignancy, accounting for less than 1% of all laryngeal cancers. It typically originates in the subglottic region and often presents with non-specific, slowly progressive respiratory symptoms, leading to frequent misdiagnosis. Case presentation We report a case of a 35-year-old non-smoking female with a five-year history of progressive dyspnoea, initially managed as asthma and subsequently as moderate obstructive sleep apnoea. Her symptoms worsened despite appropriate treatment. Imaging revealed a subglottic mass causing near-complete airway obstruction. Flexible bronchoscopy and cryobiopsy confirmed the diagnosis of adenoid cystic carcinoma of the subglottic larynx. The patient underwent an emergency tracheostomy followed by total laryngectomy. Postoperative recovery was complicated by a localized infection, which resolved with treatment. Conclusions This case illustrates the diagnostic difficulties associated with LACC due to its non-specific presentation and slow growth. It highlights the importance of considering upper airway tumours in patients with refractory respiratory symptoms and emphasizes the need for early multidisciplinary assessment, including endoscopic and radiological evaluation. Given its rarity and potential for delayed diagnosis, this case adds valuable insight into the clinical presentation and management of LACC and reinforces the importance of maintaining a broad differential diagnosis in patients with persistent airway symptoms.