GSTM1 and anemia: At 30 days after-surgery, the average FCM-treated patient presented no recognizable signs of iron deficiency anemia (being the mean of Hb: 12.6 g/dL [≥12 g/dL]; serum ferritin: 218 ng/mL [≥30 ng/mL]; and saturation transferrin index: 25.1 % [≥20 %]) compared with the no-IV group that did not reach normalized mean values (Table 3).