GSTM1 and Decreased total leukocyte count: In the second phase of this study, we found a nonsignificant trend toward an association between GSTM1 and GSTT1 gene polymorphisms and increased risk of platinum-based chemotherapy-induced toxicities like anemia, neutropenia, leukopenia, thrombocytopenia, and gastrointestinal toxicity in lung cancer patients (Table 5).