Malignant transformation in oral submucous fibrosis: Tertiary level evidence: An umbrella review

Abstract

Objectives: An umbrella review is a systematic review of systematic reviews, which provides a tertiary level of evidence. This umbrella review of systematic reviews and meta-analysis (SR-MA) aimed to determine the proportion of oral cancer (OC) development in oral submucous fibrosis (OSF) patients. Materials and Methods: We searched electronic databases including PubMed, Scopus, Web of Science, Cochrane and grey literature. Two reviewers independently screened abstracts and assessed for eligible papers. The methodological quality of SR-MA was evaluated using AMSTAR2, and we also checked the quality of evidence of the included papers. Results: Out of 454 papers identified in the primary search, 105 underwent eligibility screening. Inclusion criteria were met by four SR-MA. OC ratios ranged between 4.2% and 6% for OSF. Substantial heterogeneity was observed for this outcome in all four MA (I2 = 71.31% to 86.37%). None of the SRs assessed the quality of evidence, and half of them were judged to be of critically low methodological quality. Conclusion: There is lack of quality of evidences and critically low methodological quality among SRs and MA leading to substantial heterogeneity. However, due to potentially malignant nature, OSF patients should be monitored carefully for early detection of OC.