Pedunculated hypopharyngeal lipoma in a patient with globus sensation

A 75-year-old man presented with globus sensation, cough, and mucus production. Clinical examination was unremarkable except for dysphonia and flexible laryngoscopy revealed a large lobulated mass appeared from the posterior wall of the hypopharynx. Following the patient’s breathing, the mass moved up and down in the endolarynx (Figure 1a and video 1b).

A non-contrast CT of the neck depicted two intraluminal soft tissue lesions located respectively in the hypopharynx and the upper oesophagus (Figure 2a). The lesion in the hypopharynx appeared lobulated with thin septa and measured 14 x 20 x 20 mm, extending from the base of the epiglottis to the aryepiglottic fold (Figure 2b). The lesion displayed negative Hounsfield Units of -75, compatible with fat tissue. In the proximal oesophagus, a similar fat-containing intraluminal lesion appeared, measuring 8 x 28 x 13 mm (Figure 2c). In total, the lesions extended over an area of 10 cm.

On MRI, the lesions had a hyperintense signal on the T1-weighted (T1W) and T2-weighted (T2W) images and a hypointense signal on the fat-saturated images (Figures 3a, 3b and 3c). The lesions showed no contrast enhancement. The findings were compatible with intraluminal lipomas. A biopsy in general anaesthesia confirmed the findings.

The patient underwent surgery with micro-laryngoscopy. The lipoma appeared broad-based with three peduncles. One was with the very thin pedicle displaced to the oesophagus (Figure 4a and video 4b). The three peduncles were removed with LigaSure (Figure 5), but the most caudal part of the base could not be resected due to reduced visibility and risk of perforation. To evaluate the growth of the remaining lipoma, a yearly follow-up with flexible laryngoscopy and possibly an MRI is planned.

Lipomas are common benign tumours but account for less than 0.6% of the benign tumours in the upper airways [1]. A literature study from 2022 found just 100 cases of lipomas in the hypopharynx ever reported [2]. The lipomas are slow-growing and often asymptomatic until they reach a substantial size. This, combined with their rarity, increases the risk of delayed diagnosis and treatment. Often, they are discovered as an accidental finding on imaging. They are, however, important to be aware of, report, and treat, as they can cause asphyxia and sudden death as the first symptom. This is mainly seen with the pedunculated lipomas, which can be displaced from the oesophagus during a cough and either externalise out through the oropharynx or be aspirated and obstruct the airways [2]. Other symptoms of hypopharyngeal lipomas are similar to other space-filling lesions in the area and involve dysphagia, dyspnoea, hoarseness, stridor, cough, globus sensation, and obstructive sleep apnoea [1].

Examination of the patient should include a physical examination, laryngoscopy, imaging, and histopathological examination [2]. Endoscopically, the lipomas can vary from submucosal lesions to pedunculated lesions and with an unremarkable mucosa typical differential diagnosis would be retention cysts or internal laryngoceles [3]. CT can differentiate between these, but an MRI is necessary to differentiate between the lipoma and the malignant liposarcoma. Malignancy should be suspected if there are variable signals in T1W or T2W images and hyperintense signals in the fat-saturated images, contrast enhancement, or thick septa. Histopathological examination makes the final diagnosis [2,4].

Surgical resection should always be considered in larger and pedunculated lipomas of the hypopharynx to avoid the risk of sudden airway obstruction [2]. To avoid relapse, total resection should be aimed for, and long-term follow-up is recommended [3]. All evidence is, however, still based on case reports, and every treatment and follow-up regime should be assessed individually.

Written informed patient consent for publication has been obtained.