Prognostic assessment of different method for Eosinophils detection in Oral Tongue Cancer

Background TATE has been proposed as a prognostic factor in oral cancer staging; however, the controversial literature data limits its application in the routine diagnosis. The aim of this study was to evaluate the prognostic value of TATE in patients with oral tongue cancer. The second aim was to identify any difference in the methods of eosinophil quantification or in the cut-off values reported in literature. Methods Clinic-pathological data of 204 patients treated at "Ospedali Riuniti" Hospital, Ancona, Italy, were collected. Evaluation of TATE was performed on hematoxylin and eosin-stained slides and correlation with survival outcomes evaluated. The number of eosinophils per square millimeter was evaluated by using two methods, namely density (TATE-1) and classical (TATE-2) methods. For each of the two methods tested, patients were stratified into two or three groups, according to the most used cut-off values reported in literature. Results Regardless of the method of eosinophil quantification or the cut-off values used, patients with high TATE had a significant better disease-specific survival. The density method (TATE-1) showed a better predictive performance, in particular when applying a single cut-off of 67 eosinophils/mm2 , two cut-offs of 10 and 100 eosinophils/mm2 , or two cut-offs of 50 and 120 eosinophils/mm2 . Conclusion The evaluation of TATE is simple, cost-effective, and easy to implement in daily practice with the aim of improving risk stratification of patients affected by oral tongue cancer. Results of prognostic performance analysis suggest using density (TATE-1) method as the standard approach to evaluate TATE in future studies, enhancing replicability.