Malignant transformation of calcifying epithelial odontogenic tumour: A systematic review

The calcifying epithelial odontogenic tumor (CEOT) is a rare benign epithelial odontogenic neoplasm. Some cases of CEOT may undergo malignant transformation, whose characteristics are still poorly known. This study aimed to perform a systematic review of CEOT cases with malignant transformation.

This systematic review followed the preferred reporting items for systematic reviews and meta-analyses (PRISMA) and was registered with PROSPERO (CRD42021285981). Searches for full-text articles on histopathologically confirmed CEOT cases with malignant transformation were performed in different databases (PubMed/ MEDLINE, Embase, Scopus, Web of Science, LILACS, SciELO, Google Scholar, Open Grey, and CAPES Dissertation and Thesis Catalog) without year of publication or language restrictions. A qualitative descriptive and risk of bias analysis were performed.

Nine cases were included, with a mean age of 59.44 (±17.07) years and a slightly higher frequency in males (55.6%). The mandible (88.9%) was the most affected site, with predominance of the mixed imaging pattern (77.8%). Histopathologically, the clear cell variant, intense mitotic activity, presence of cellular atypia, and high Ki-67 immunoexpression were the predominant findings. Isolated surgery (44.4%) was the most common treatment and recurrence of CEOT before malignant transformation was observed in five cases (55.6%). CEOT with malignant transformation recurred in three cases (33.3%). Most cases had a positive outcome (77.8%), with remission of the disease.

This systematic review determined the clinicopathological profile of histopathologically confirmed cases of CEOT with malignant transformation and synthesized some characteristics that can assist in the diagnosis and appropriate therapeutic approach of this rare neoplasm. Key words:Systematic review, Odontogenic tumors, Clinicopathologic features, Treatment, Prognosis.