Accumulating studies have employed clinical factors such as hypertension history, diabetes history,3 and hematological biomarkers including hemoglobin (Hb), platelets (PLTs) and white blood cells (WBCs), in the prognostic analysis of lung cancer patients.4 However, these studies did not reach consensus on cutoff values and biomarkers selection, which may lead to inaccurate conclusions. Here, GSTM1 is linked to lung cancer.