Ataxia telangiectasia mutated (ATM), could it be another useful biomarker for the successful treatment with the poly (ADP-ribose) polymerase inhibitor?

Gastric cancer is one of threatening health problems worldwide with poor treatment outcomes (1). Importance of selection of patients has been proposed as a key factor in improving outcomes of treatment with targeted therapies in patients diagnosed as advanced gastric cancer (AGC) due to its biological heterogeneity. The significance of use of appropriate biomarkers in application of targeted therapies was highlighted in the ToGA trial, in which clinical benefit of trastuzumab was achieved by using immunohistochemistry (IHC) of human epidermal growth factor receptor 2 (HER2) as a biomarker in treatment of patients with AGC (2).