Unexpected histology – ectopic salivary gland in the false vocal cord

INTRODUCTION

Salivary glands are exocrine structures responsible for secreting saliva, facilitating digestion, and maintaining oral health.¹ These glands are categorized into major and minor types.^1,2 The major salivary glands include the parotid, submandibular, and sublingual glands, while the minor salivary glands, numbering between 800 and 1,000, are dispersed throughout the submucosa of the oral cavity and upper aerodigestive tract.^1,2 The minor glands are particularly abundant in areas such as the lips, cheeks, palate, and tongue.²

Ectopic salivary glands, also known as heterotopic salivary gland tissue, are rare anomalies where salivary gland tissue is located outside its normal anatomical boundaries. These ectopic glands have been documented in various regions, including the middle ear, thyroid gland, cervical lymph nodes, and even the rectum and vulva.

Among the most uncommon sites for ectopic salivary glands is the larynx, specifically the vocal cords. To date, only a limited number of cases have been reported in the English literature.

This is one case of an ectopic salivary gland tissue found in the vocal cord of a 57-year-old male who presented with complaints of throat discomfort.

CASE REPORT

A 57-year-old male presented to the ENT outpatient department with a primary complaint of persistent throat pain lasting for six months. Notably, he did not report any hoarseness, dysphagia, or otologic or nasal symptoms. His medical history included a two-year regimen of proton pump inhibitors for gastroesophageal reflux disease (GERD). The patient had a significant smoking history of 39 years, consuming approximately 15 beedis daily, but denied alcohol or other substance use.

Clinical examination revealed a cystic lesion in the right vallecula and a smooth mass in the anterior third of the right vocal cord. Laryngeal mobility remained intact. A contrast-enhanced computed tomography (CECT) scan of the neck identified a small polypoidal protrusion on the posterior aspect of the right vocal cord.

The patient underwent microlaryngeal surgery under general anesthesia, during which the lesion was excised in toto. Gross examination of the excised mass suggested a lipoma, characterized by its soft consistency and the presence of oil droplets when floated in saline. Histopathological analysis, however, revealed benign mature adipocytes interspersed with lobules of seromucinous salivary gland tissue, leading to a final diagnosis of ectopic salivary gland tissue.

The postoperative course was uneventful, and the patient was discharged with instructions for voice rest. He was also advised on lifestyle modifications, including smoking cessation. Given the rarity of ectopic salivary glands in the vocal cords, this case underscores the importance of considering such anomalies in the differential diagnosis of laryngeal masses. Long-term follow-up is recommended to monitor for potential recurrence.

DISCUSSION

Vocal fold mucosal lesions encompass a diverse spectrum, ranging from benign conditions such as vocal nodules and polyps to more complex pathologies like mucosal hemorrhage, intra-cordal cysts, and glottic sulci. While many of these lesions are benign and result from vibratory injury, some can be malignant. Patients typically present with hoarseness, a common symptom associated with these conditions. Management often involves surgical resection followed by voice rest to promote healing and restore normal vocal function.

An ectopic salivary gland in the vocal cord is an exceedingly rare entity, with only a few cases documented worldwide.^3-6 To date, only nine instances of ectopic salivary glands in the larynx have been identified, with just three occurring in the vocal cords, making this patient the fourth reported case.³

Salivary glands develop bilaterally through epithelial–mesenchymal interactions between the ectodermal epithelial lining of the oral cavity and the subjacent neural crest-derived mesenchyme.^1,4 This process begins around six to eight weeks of gestation and concludes at 28 weeks, after which acini start producing secretions.^1,4 Ectopic salivary glands are believed to form when salivary gland tissue deviates from its normal migratory path during embryonic development. The precise mechanisms underlying this aberrant migration remain unclear.

Patients may present with hoarseness, throat discomfort, or be asymptomatic. In this case, the patient presented with throat pain but did not report hoarseness or other symptoms. There is no literature to suggest that smoking exacerbates symptoms.

Surgical intervention is typically not necessary unless there is evidence of malignancy. In this patient, surgery was performed due to persistent throat pain and the preoperative appearance of the lesion. The lesion was completely excised, and histopathological analysis confirmed the presence of salivary gland tissue, leading to a diagnosis of ectopic salivary gland.

Imaging studies are essential to rule out malignant lesions. A contrast-enhanced computed tomography (CECT) scan of the neck was performed in this patient to assess the lesion's characteristics. Magnetic resonance imaging (MRI) is often preferred for evaluating soft tissue lesions and can provide detailed information to differentiate benign from malignant masses.^3,5

Recurrence of ectopic salivary glands has been documented in some cases, likely due to incomplete resection. Complete excision of the lesion with clear margins is crucial to minimize the risk of recurrence. Regular follow-up is recommended to monitor for any signs of regrowth.

CONCLUSION

In conclusion, while ectopic salivary glands in the vocal cords are exceedingly rare, they should be considered in the differential diagnosis when evaluating submucosal masses in this region. Early recognition and appropriate surgical management are crucial to prevent complications and ensure favorable patient outcomes.

Funding: No funding sources

Conflict of interest: None declared

Ethical approval: Not required

REFERENCES

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