GSTM1 and neoplasm: His blood tests revealed the following: white blood cell count (WBC) 9.3 × 103 K/μl, hemoglobin (Hb) 13.2 g/dl, and tumor markers carcinoembryonic antigen (CEA) 1.2 ng/ml and squamous cell carcinoma (SCC) 0.4 ng/ml, all within normal range.