Lipomas are benign tumours of mesenchymal origin characterised by the proliferation of mature adipocytes. They are frequently encountered in the subcutaneous tissues; however, lesions arising within the head and neck constitute a relatively small proportion of cases. Lipomas involving the retropharyngeal or prevertebral spaces are particularly rare because of the deep anatomical location and limited available space within these compartments. A systematic review involving 79 cases of retropharyngeal lipoma reported dysphagia as the predominant presenting complaint, with computed tomography (CT) being the principal diagnostic imaging modality and surgical excision representing the most commonly adopted treatment [1]. Depending on their size and location, these lesions may produce progressive compression of the upper aerodigestive tract, resulting in symptoms such as dysphagia, dyspnoea, globus sensation, snoring, alterations in voice, and obstructive sleep apnoea (OSA) [7-15]. The retropharyngeal and prevertebral spaces are anatomically deep cervical compartments located posterior to the pharyngeal structures. A mass arising in these spaces can exert considerable anterior pressure on the pharyngeal wall while leaving the overlying mucosa intact [2]. As a result, the clinical appearance may closely resemble that of a primary submucosal lesion of the oropharynx, potentially leading to diagnostic uncertainty. Recognition of the lesion's deep anatomical origin is therefore important for appropriate imaging, surgical planning, and management. We describe a rare symptomatic lipoma arising in the upper cervical prevertebral space that presented clinically as a posterior pharyngeal wall swelling and was successfully treated through an endoscopic transoral approach.

Patient Information: A 75-year-old female was evaluated in the otorhinolaryngology outpatient department for complaints that had persisted for approximately six months. Her symptoms included a constant sensation of something lodged in the throat, difficulty swallowing, particularly solid foods, and repeated episodes of nasal regurgitation. She also reported loud habitual snoring and symptoms consistent with disturbed breathing during sleep. There was no history of previous trauma, pharyngeal surgery, or other relevant local intervention. Patient identifiers were removed from the report to maintain confidentiality and comply with publication requirements. Clinical Findings: On intraoral examination, a distinct swelling was noted along the posterior pharyngeal wall, measuring approximately 3.2 cm at its most prominent point and showing greater prominence on the left side. The surface was covered by normal-appearing, intact mucosa without ulceration or other mucosal abnormalities. No palpable cervical lymph nodes were detected. Flexible nasopharyngolaryngoscopy demonstrated a smooth, well-defined submucosal prominence of the posterior pharyngeal wall with no visible mucosal pathology. Despite the presence of the mass, the airway remained adequately patent in the awake state. Timeline Time Clinical event Approximately 6 months preoperatively Foreign-body sensation, solid-predominant dysphagia, recurrent nasal regurgitation, snoring, and sleep-disordered breathing symptoms developed. 26 May 2025 Contrast-enhanced CT demonstrated a 1.5 × 2.7 × 4.0-cm left prevertebral fat-density lesion from the skull base to the lower margin of C2; preoperative level 2 sleep study showed AHI 30 events/hour. 5 June 2025 Endoscopic transoral excision of the prevertebral lipoma was performed; the encapsulated mass was removed en bloc. Postoperative days 1–7 Ryle’s-tube feeding was maintained. No airway, bleeding, infective, neurological, or swallowing complication occurred. Postoperative day 7 Exposed pharyngeal sutures were removed; oral intake progressed from liquids to semisolids and then solids. 9 June 2025 Histopathology report HP-245/25 confirmed lipoma. 1 month Operative site completely healed; dysphagia, regurgitation, globus, and sleep-related symptoms had improved. 1 year No dysphagia, clinically significant OSA symptoms, or recurrence was found. Follow-up AHI was 5 events/hour. Diagnostic assessment Contrast-enhanced computed tomography (CT) of the neck, performed on 26 May 2025, demonstrated a well-circumscribed lesion of predominantly fat attenuation within the left prevertebral space. The lesion extended superiorly from the skull base to the inferior level of C2 and crossed towards the midline. It measured approximately 1.5 cm in the anteroposterior dimension, 2.7 cm transversely, and 4.0 cm craniocaudally, with an attenuation value of approximately −114 Hounsfield units (HU), consistent with adipose tissue. The mass caused mild anterior displacement of the left longus capitis muscle and resulted in mild-to-moderate reduction of the nasopharyngeal and oropharyngeal airway calibre. Although it was in close proximity to the upper cervical vertebral bodies, there was no evidence of adjacent osseous destruction, erosion, or sclerosis. A distinct preserved fat plane was maintained between the lesion and the left internal carotid artery, suggesting the absence of vascular invasion. Based on its characteristic fat attenuation, well-defined margins, anatomical location, and lack of bone or vascular involvement, the imaging findings were considered highly suggestive of a prevertebral lipoma. A preoperative level 2 sleep study demonstrated severe OSA, with an AHI of 30 events/hour. Panendoscopic examination under anaesthesia confirmed an intact mucosal surface over the posterior pharyngeal bulge and helped define transoral access.A posterior pharyngeal wall swelling with a smooth and intact surface may arise from several benign or malignant pathologies. The differential diagnosis includes benign mesenchymal tumours, congenital or developmental cysts, lymphoma, primary neoplasms, and metastatic lesions. Retropharyngeal infection or abscess should also be considered, particularly when the presentation is acute and associated with inflammatory symptoms. Imaging characteristics are important in distinguishing these entities. A well-defined lesion composed predominantly of homogeneous macroscopic fat, without evidence of local invasion, is highly suggestive of a lipoma. Conversely, the presence of thick or irregular septations, nodular soft tissue areas, non-fatty components, or extension into surrounding structures should raise concern for an atypical lipomatous tumour or liposarcoma and may require additional imaging, biopsy, or histopathological assessment. Therapeutic intervention Following detailed counselling regarding the available transoral and external surgical approaches, written informed consent was obtained from the patient. The potential complications discussed included haemorrhage, infection, postoperative pain, dysphagia, aspiration, velopharyngeal dysfunction, nasal regurgitation, airway obstruction with the possible need for tracheostomy, injury to adjacent neurovascular or prevertebral structures, incomplete tumour removal, recurrence, and the possibility of converting to an external cervical approach if adequate and safe transoral access could not be achieved. The patient underwent endoscopic transoral excision under general anaesthesia on 5 June 2025. The airway was secured with orotracheal intubation using a flexometallic reinforced tube. Equipment and personnel required for emergency tracheostomy were kept readily available; however, tracheostomy was not necessary. The patient was placed in the supine position with the neck extended in the Rose position, commonly used for tonsillectomy procedures. Adequate surgical exposure was achieved using a Boyle-Davis mouth gag with a Doughty tongue blade, supported by a Draffin bipod stand. With endoscopic guidance, a vertical midline incision was made over the area of maximal posterior pharyngeal wall prominence. The submucosal pharyngobasilar fascial layer was carefully divided, followed by separation of the underlying constrictor muscle fibres in the midline. The muscle was gently retracted laterally to facilitate access. The buccopharyngeal fascia was subsequently opened, allowing identification of the lesion capsule within the prevertebral plane. Circumferential mobilisation of the encapsulated mass was performed using a combination of blunt and sharp dissection. After adequate release of the lesion from the surrounding tissues, its attachment at the base was divided, and the mass was removed completely in a single intact specimen. Limited bipolar cauterisation was performed at the base to achieve haemostasis. The mucosal wound was subsequently closed in layers using 4-0 polyglactin 910 (Vicryl) absorbable sutures. The suture ends were trimmed short to minimise postoperative pharyngeal irritation. A Ryle's tube was inserted to facilitate enteral feeding during the immediate postoperative period. Perioperative antibiotics were administered in accordance with institutional protocol. Benzydamine hydrochloride 0.15% mouthwash was prescribed for local symptomatic relief, with 15 mL to be gargled and expectorated as required. The excised specimen consisted of a solitary, well encapsulated, soft, yellowish mass measuring 4 × 2 × 1 cm, corresponding closely with the 4.0 cm craniocaudal dimension identified on preoperative CT. The specimen was submitted for histopathological examination to the Department of Pathology, Madha Medical College & Research Institute, where it was registered under specimen number HP-245/25. Follow-up and outcomes The postoperative period was uneventful. Ryle’s tube feeding was maintained during the first postoperative week. No episodes of bleeding, infection, airway compromise, aspiration, neurological deficit, or other postoperative complications were observed. On postoperative day 7, the exposed sutures were intentionally removed to prevent spontaneous loosening and the potential risk of aspiration. Oral feeding was subsequently resumed gradually, progressing from liquids to semisolids and then to solid foods as tolerated. Histopathological examination, received on 5 June and reported on 9 June 2025 (HP-245/25), revealed an encapsulated tumour consisting of lobules of mature adipose tissue separated by fibrous septa, confirming the diagnosis of lipoma. No atypical or malignant features were identified. At the one month follow-up, the surgical site had healed completely, and the patient reported substantial improvement in the sensation of a foreign body, dysphagia, nasal regurgitation, and sleep related symptoms. Clinical surveillance was continued for one year to monitor for dysphagia, recurrence of OSA symptoms, and local tumour recurrence. At the final follow-up, the patient remained clinically well, was tolerating a normal diet, and had no evidence of recurrence or swallowing- or airway-related complications. Follow-up sleep assessment demonstrated an AHI of 5 events/hour, compared with 30 events/hour before surgery.

Retropharyngeal and prevertebral lipomas are uncommon lesions, but their clinical presentation follows a recognisable pattern. Their gradual enlargement within the relatively compliant deep cervical spaces may allow substantial growth before compression of the upper aerodigestive tract produces symptoms. A 2022 systematic review reported dysphagia in 65.2% of patients, with surgical treatment performed in 93.6% of cases and a transoral approach used in 38.4% of surgically treated patients [1]. In the present case, the combination of a persistent foreign body sensation, predominantly solid-food dysphagia, nasal regurgitation, snoring, and a smooth posterior pharyngeal wall prominence was consistent with symptoms resulting from progressive local mass effect. Computed tomography is generally effective for identifying a typical lipoma because macroscopic fat demonstrates characteristic low attenuation on CT. Simple lipomas usually appear homogeneous, well circumscribed, and without significant enhancement [1,2,11,12]. Magnetic resonance imaging can provide additional information regarding soft tissue planes and demonstrate suppression of the fat signal, particularly when the lesion is large, atypical in appearance, or situated near important neurovascular structures [2,10,11]. Assessment of the superior to inferior and lateral extent of the lesion is also important because its anatomical distribution directly influences the feasibility and choice of surgical approach. Although imaging can strongly suggest the diagnosis, histopathological examination remains essential for definitive confirmation and for excluding atypical adipocytic or malignant features [7,9,11]. Both transoral and transcervical approaches have been reported for the management of retropharyngeal and prevertebral lipomas [1,3-7,9-15]. A transoral approach provides direct access to lesions that present medially within the upper prevertebral region while avoiding an external cervical scar and extensive dissection around cervical neurovascular structures. Previous reports have demonstrated successful transoral removal of relatively large lesions when adequate exposure is possible and the tumour has limited lateral or inferior extension [3,4,12,13]. More advanced techniques, including robot-assisted surgery and combined endoscopic transoral and transnasal approaches, have also been described for anatomically challenging prevertebral or intramuscular lipomas [10,15]. In contrast, a transcervical approach may be preferable for very large lesions, substantial parapharyngeal extension, poorly defined tissue planes, or cases in which airway or vascular control is expected to be difficult [5,9,11]. Therefore, the choice of surgical route should be based on the lesion's anatomical characteristics, imaging findings, airway assessment, and the surgeon's experience. Lipomas situated within the upper airway can contribute to obstructive sleep apnoea by reducing the available pharyngeal airway space [4,8,9,14]. One previously reported case managed through a transoral approach demonstrated a reduction in the apnoea-hypopnoea index from 26 to 2.2 events/hour following tumour removal [14]. In the present case, the reduction in AHI from 30 to 5 events/hour following excision suggests improvement in a mechanical component of the sleep-disordered breathing. However, because postoperative weight, sleep position, and other complete polysomnographic parameters were not available, the improvement cannot be attributed entirely to removal of the lesion. The improvement in OSA is therefore considered a secondary functional benefit rather than the primary indication for surgery. The present case highlights an important diagnostic consideration because the visible posterior pharyngeal wall prominence initially suggested an oropharyngeal submucosal lesion, whereas CT demonstrated its origin within the upper prevertebral space. Despite its relatively small dimensions, the lesion produced clinically significant symptoms through airway and pharyngeal compression. Complete en bloc removal, histopathological confirmation, an uncomplicated postoperative course, and one year of clinical follow-up demonstrate that endoscopic transoral excision can be an effective treatment option for appropriately selected upper prevertebral lipomas. The limitations of this report include its single patient design, the absence of postoperative cross-sectional imaging, and limited paired sleep study information beyond the AHI values.

A prevertebral or retropharyngeal lipoma should be included in the differential diagnosis of a smooth posterior pharyngeal wall bulge associated with slowly progressive dysphagia or regurgitation. Complete endoscopic evaluation and cross-sectional imaging clarify the lesion’s origin and extent. In selected, medially accessible lesions, transoral excision can provide definitive treatment while avoiding an external cervical approach. Patient Perspective A formal written patient-perspective narrative was not collected. During follow-up, the patient reported that swallowing, throat discomfort, nasal regurgitation, and sleep-related symptoms had improved and that she had returned to a normal diet. Declarations

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