Lichenoid lesions of the upper labial mucosa: a systematic review and a report of a new case with extensive follow-up.

The paper reports the demographic characteristics of patients with lichenoid lesions affecting only the upper labial mucosa, with or without associated lesions in the maxillary anterior gingiva, alongside the lesions' clinical and histopathological features, treatment, follow-up and prognosis. Also, a new case with lengthy follow-up is presented. A systematic review was performed in line with PRISMA guidelines. The literature search sources were PubMed, Scopus and Web of Science. In all, 26 patients (21 women, 5 men) were included in the review. 80.8% ( Lichenoid lesions found solely in the upper labial mucosa, with or without adjacent gingival lesions, are rarely reported in the literature, and the reporting is often incomplete. A definitive aetiology could not be established for the lesions. Likewise, there is little information about this condition's long-term prognosis.