Although post-RT anemia level was non-significant in the adjuvant setting (51.3% vs 70.4%; p = 0.195) in contrast to definitively RT recipients (38.3% vs 60.3%; p = 0.04) for RT-alone vs RT plus cetuximab, overall anemia/Hb improvements were significant only for adjuvant RT (56.4% vs 25.9%; p = 0.014), unlike the definitive RT setting (21.3% vs 15.5%; p = 0.446) for both study groups respectively. Here, GSTM1 is linked to anemia (phenotype).