Evaluation of urinary CA19-9 levels in bladder cancer patients classified according to the combinations of Lewis and Secretor blood group genotypes.

OBJECTIVES: This study evaluated the clinical significance of urinary CA19-9 levels in bladder cancer patients classified according to various combinations of Lewis (Le) and Secretor (Se) genotypes. METHODS: Urinary CA19-9 and DU-PAN-2 levels were measured as units per mg creatinine (U/mg Cr) in 121 patients with bladder cancer and in 31 patients with other urologic diseases. Genotyping was carried out using polymerase chain reaction-based methods. RESULTS: Urinary CA19-9-values in patients with both Le and Se alleles (Le/Le, Se/Se; Le/Le, Se/se; Le/le, Se/Se; Le/le, Se/se) were significantly higher (P < 0.0001) in bladder cancer cases compared to the other urologic diseases. The cut-off value determined using receiver operating characteristics analyses was 37.6 U/mg Cr. Approximately 70% (57/87) of bladder cancer patients with both Le and Se alleles demonstrated urinary CA19-9 levels over the cut-off value. In contrast, only 16% (4/24) of patients with other urologic diseases were over the cut-off value. CONCLUSIONS: The urinary CA19-9 level can be a new effective diagnostic tool in bladder cancer patients with both Le and Se alleles.