The predictive marker, tumor mutational burden (TMB): controversies and facts

Kiss András (1,2), Fillinger János (2,3), Méhes Gábor (2,4), Barbai Tamás (1), Rásó Erzsébet (1), Sükösd Farkas (5), Tornóczki Tamás (2,6), Tímár József (1)
(1) Semmelweis Egyetem, II. Sz. Patológiai Intézet, Budapest
(2) Egészségügyi Szakmai Kollégium, Patológiai Tagozat
(3) Országos Korányi Pulmonológiai Intézet, Budapest
(4) Debreceni Egyetem, Patológiai Intézet, Debrecen
(5) Szegedi Tudományegyetem, Patológiai Intézet, Szeged
(6) Pécsi Tudományegyetem, Patológiai Intézet, Pécs

Tumor mutational burden (TMB) is a sensitive marker of the carcinogenic damages of the tumor genome, but its definition and the exact technical protocol of its determination is not widely accepted. Meanwhile TMB became as one of the predictive marker of administration of immune checkpoint inhibitors (ICI). Recently several large multicentric studies analysed the technologies of TMB determination and identified problematic key factors. On the other hand, several retrospective analyses of the clinical trials data revealed problems of the use of high TMB as predictor of efficacy of ICI administration in a wide variety of malignancies. Before introducing widely TMB as predictive biomarker in Hungary, we have summarized TMB-associated knowledge and the relevant ESMO guidance to support decisions of
multidisciplinary teams.