Significance of p53 overexpression in the prediction of the malignant transformation risk of oral potentially malignant disorders: A systematic review and meta-analysis.

OBJECTIVES: To evaluate the current evidence in relation to the predictive value of p53 overexpression as a biomarker of the malignant transformation risk in oral potentially malignant disorders (OPMD). MATERIAL AND METHODS: We searched PubMed, Embase, Web of Science and Scopus for studies published before July-2021, not restricted by date or publication language, with longitudinal design and assessing p53 overexpression by immunohistochemistry. We evaluated the quality of primary-level studies using QUIPS tool. We carried out meta-analyses, examined inter-study heterogeneity through subgroup and meta-regression analyses, and performed sensitivity and small-study effects analyses to test the stability and reliability of results. RESULTS: Twenty four studies (1,210 patients) met inclusion criteria. P53 overexpression was associated with a statistically significant about 2 fold risk (RR = 1.88, 95 %CI = 1.39-2.56, p < 0.001). Leukoplakia maintained this significant relationship after subgroup meta-analysis (p = 0.002). Regarding the immunohistochemical technique, better results were obtained by the subgroups using anti-p53 DO7 antibody (p = 0.001), at high concentration (dilution < 1: 100, p < 0.001), incubated for long periods (overnight, p = 0.02), and at low temperature (4 degrees C, p = 0.007). Furthermore, meta-regression analysis showed that the association between p53 overexpression and higher oral cancer risk was independent of the presence and/or severity of epithelial dysplasia (p > 0.05). CONCLUSION: Our systematic review and meta-analysis supports the assessment of p53 overexpression in the prediction of the malignant transformation risk of OPMD.