Uncommon Histopathological Variants of a Common Lesion: Mucocele

A mucocele is a salivary gland cyst, which contains mucous material. It usually arises from the minor salivary glands and is broadly of two types: mucus retention cysts and mucus extravasation phenomenon. A wide variety of histological features have been documented in the literature such as myxoglobulosis, mucoceles presenting papillary synovial metaplasia-like changes, superficial mucoceles, and clear cell changes. The present case shows histological features of myxoglobulosis and papillary synovial metaplasia like changes (PSM like changes). This paper reports a case of a 17 years old male patient with a chief complaint of a painless swelling on the lower lip since one and half year. Upon a provisional diagnosis of mucocele, surgical excision was carried out. Histopathological examination revealed a mucus extravasation cyst having lumen filled with unique mucinous globular structures, myxoglobulosis and papillary synovial metaplasia like changes.