Oral focal mucinosis: A systematic review

Oral focal mucinosis (OFM) is a rare lesion first described in 1974, but the aetiology remains unknown. Clinically, OFM presents as an asymptomatic nodular lesion and the similarity of clinical features to other soft tissue injuries makes the diagnosis difficult. The aim of this study was to integrate the demographic, clinical, and histopathological characteristics from previously published cases of OFM into a systematic review. Electronic searches without publication date restriction were performed in the following databases: Embase, PubMed, Medline, Web of Science, and Scopus. Case reports or case series of OFM published in English and presenting enough clinical and histopathological information were included. This systematic review identified 42 studies from 12 countries, comprising 113 cases of OFM. This lesion affected more females than males, usually in the fourth decade of life. The gingiva was the most common anatomical location, followed by the palate. Clinical presentation was most often an asymptomatic nodule. Imaging exams revealed that most cases did not have bone involvement. Surgical removal was the treatment of choice for most cases and only one recurrent case was reported. In conclusion, OFM is an uncommon pathology, and its diagnosis depends on histopathological analysis. The lesion could be included as a differential diagnosis of benign soft tissue lesions of the oral cavity, especially those affecting the gingiva.