Sialolipoma of Parotid Gland a Rare Histological Presentation

Case report: Rare case of recurring cervical sialolipoma

INTRODUCTION AND IMPORTANCE

Sialolipomas are benign and slow-growing lesions arising from minor and major salivary glands. They constitute a rare subtype of lipomas, with a low rate of recurrence. This article describes the case of a patient presenting with recurring sialolipoma.

CASE PRESENTATION

A 56-year-old patient presented with a voluminous lipomatous lesion on the right cervical side. The histopathological analysis after the surgical removal of the lesion revealed sialolipoma, a recurring of a similar lesion treated ten years ago.

CLINICAL DISCUSSION

Sialolipomas are relatively rare lesions occurring mainly in adults. Their structure is composed of salivary glands' elements and adipocytes. Many histological forms exist and have been described, like oncocytic lipoadenomas or pleomorphic adenomas for example. Sialolipomas are usually asymptomatic, and the patients experience no pain. The etiology of sialolipomas would be due to salivary glands dysfunctions, resulting in altered gland configuration. The treatment of choice for this type of lesion is complete excision by surgery. It was the curative approach used here.

CONCLUSION

A patient presented with a big mass on the right cervical side, which turned out to be sialolipoma, a benign lesion. It was the recurring of a similar tumor treated ten years ago. The lesion has been treated by surgery.

Sialolipomas of minor salivary glands: A multi-institutional study and literature review

BACKGROUND

Sialolipoma is a rare histological variant of lipoma commonly misdiagnosed and composed of a proliferation of mature adipocytes with secondary entrapment of normal salivary gland tissue. The purpose of the present study is to report the clinicopathologic and immunohistochemical features of 10 new cases of sialolipomas in conjunction with a review of the literature.

METHODS

A retrospective descriptive cross-sectional study was performed. A total of 54,190 biopsy records of oral and maxillofacial lesions from four oral and maxillofacial pathology services in Brazil were analysed. All cases of lipomas were reviewed, and clinical, demographic and histopathological data were collected of all cases compatible with sialolipomas. In addition, immunohistochemistry stains (AE1/AE3, CK7, 34βE12, S-100, HHF35, α-SMA and Ki-67) and a literature review based on a search of three electronic databases (PubMed, Web of Science and Scopus) were performed.

RESULTS

Among all lipomas reviewed, there were 10 cases of sialolipomas. The series comprised of 7 females (70.0%) and 3 males (30.0%), with a mean age of 46.1 ± 21.5 years (range: 11-71 years) and a 2.3:1 female-to-male ratio. The lower lip (n = 3, 30.0%) and tongue (n = 2, 20.0%) were the most common locations, presenting clinically as a nodule of slow growth and normal colour. Conservative surgical excision was the treatment in all cases. No recurrence was observed.

CONCLUSION

Sialolipomas are a rare histological variant of lipoma, affecting the salivary glands, mainly in the parotid gland and palate of female adults. Pathologists must recognise sialolipomas to avoid misdiagnoses with other lipomatous tumours that can affect salivary glands.