GSTM1 and colorectal carcinoma: Laso-Morales et al. [48] reported a greater increase in Hb in patients with CRC who received IV iron sucrose of varying dose compared to patients who received oral elemental iron (2.0±1.5 g/dL vs. 1.1±1.2 g/dL; p = 0.001) from postoperative day one to postoperative day 30.