Keywords: biomarkers; liquid biopsy; microRNA; oral squamous cell carcinoma; prognosis; saliva.
In management of oral squamous cell carcinoma (OSCC), only a few biomarkers, ranging from clinical and histopathological features to molecular alterations, have been demonstrated to have clinical and prognostic utility. The intent of this narrative review is to present current findings on the use of salivary microRNAs (miRNAs) as prognostic oncologic biomarkers in patients with OSCC. The ability to predict survival or recurrence during follow-up by quantification of specific miRNAs in saliva has been shown in a number of studies, and serves as a possible feature to address in future well-designed clinical studies to confirm their prognostic value. The non-invasiveness of liquid biopsy techniques, the ease of saliva collection, and the abundance and stability of miRNAs in such a biologic fluid make it an attractive combination to improve management of OSCC. For salivary miRNAs to be used in routine practice, however, methodological and sampling standardisation are still needed to increase the power and accuracy of the results obtained.