GSTM1 and neoplasm: Univariate analysis revealed that sex (p = 0.004), two-dimensional (2D) tumor area (p < 0.001), sinus involvement (p = 0.014), World Health Organization grade (p = 0.015), preoperative albumin level (p = 0.032), preoperative Hb level (p = 0.001) and preoperative platelet count (p = 0.004) were significantly associated with greater IBL.