Factors Associated with Recurrence of Ameloblastoma: A Scoping Review

PurposeThis scoping review aimed to identify factors associated with the recurrence of ameloblastoma.MethodsSystematic searches were conducted in PubMed, Scopus, and EMBASE, based on the board research question: "What factors are related to the recurrence of ameloblastoma?". English-language observational studies addressing the risk and preventive factors associated with recurrent ameloblastoma were included and data were extracted.ResultsEighty-three retrospective observational studies met the inclusion criteria. The identified prognostic factors for recurrence included: (1) Tumor size/diameter/volume, (2) cortical bone perforation/ soft tissue invasion, (3) multilocular radiolucency, (4) impacted tooth-involving lesions, (5) root resorption, (6) WHO classification - conventional (solid/multicystic) ameloblastoma, (7) histological subtype - mural invasion of unicystic ameloblastoma, (8) conservative treatment modalities - simple enucleation, curettage, and marsupialization, and (9) non-extraction/preservation of involved teeth. No strong evidence linked immunohistochemical expression to recurrence. Interestingly, BRAF p.V600E remained controversial in terms of recurrence, despite being a frequent finding in ameloblastoma.ConclusionCertain clinical characteristics, radiographic findings, histological subtypes, and treatment choices of ameloblastoma can help identify patients at high risk of recurrence. Further prospective studies to evaluate the prognostic factor model and research on immunohistochemistry are required.