Bilateral Mucous Retention Cyst of the Submandibular Salivary Gland: A Rare Unusual Presentation and Review of the Literature.

Background: Mucous Retention Cyst (MRC) are non-neoplastic, developmental salivary gland lesion. Although more common in the minor salivary gland, few cases have been reported in the major salivary gland. Objective: To draw the attention of clinicians to a rare occurrence of MRC in the submandibular gland bilaterally.   Case Report: The index case presents as a slowly progressive painless lesion of 10 years duration associated with aesthetics concerns. The lesion appeared as a double jaw with extension into the neck. Though lobulated and fluctuant, aspirate yielded yellow coloured, non-viscous and non-foul smelling fluid. Ultrasonography revealed a multilobulated mass with mobile heterogeneous fluid-like content in the submental and submandibular regions bilaterally. The massive size of the lesion limited the ultrasonic visualization of the submandibular salivary glands. The patient could not afford advanced imaging. During surgery, the lesion had involved the submandibular gland bilaterally with attachment to the hyoid bone and in close relation to the recurrent laryngeal nerve. Although the nerve was preserved, the patient experienced temporary hoarseness, which resolved with medication. Histopathologic examination of the excised lesion revealed the lesion as Mucous Retention Cyst. Conclusion: The massive size of the lesion, delayed presentation and financial constraints in obtaining advanced imaging could have contributed to the diagnostic dilemma. This rare case will help the clinicians include MRC as a differential diagnosis of lesions involving submandibular salivary gland bilaterally. It also draws the attention of the maxillofacial surgeons to the unexpected injury to the recurrent laryngeal nerve and its management in a low-income setting environment.