When the primary tumours of lymph node positive cases (Dukes C, stage 3) were compared to the paired lymph node metastasis, expression of CYP2R1, CYP8B1, CYP39A1, CYP46A1 and CYP51A1 were each significantly reduced in the lymph node metastasis. This evidence concerns the gene CYP39A1 and neoplasm.