Can the levels of nitric oxide in the urine, serum and tumor tissue be putative markers for bladder cancer?

Abstract

To determine nitric oxide (NO) levels in serum, urine, tumor tissue and non-malignant adjacent tissue in bladder cancer patients compared with those in patients with a non-neoplastic genitourinary disease and to evaluate postoperative serum and urine NO change. Samples was collected in 20 cancer and 41 control patients. Griess reagent was used for NO measurements. Mean age in the cancer and control groups was 64.2 +/- 9.9 and 63.7 +/- 8.9 years, respectively. Preoperatively, urinary infection incidence was not statistically different between groups. There were no significant differences in serum, urine and tissue NO levels in patients with and without infection in both groups. Hematuria was found to not affect urine NO level in the cancer group. Urine NO level was significantly higher than in controls preoperatively, decreased significantly following operation and remained stable after the third month. High serum NO values decreased at the early postoperative period; however, they re-increased in the long-term. No significant differences were observed in the third month in serum and urine NO levels between the patients with (no. 6) and without (no. 14) residual or relapsing tumor. No statistical difference was observed between NO levels in non-malignant adjacent and control tissues. However, tumor tissue NO level was significantly higher than those in the other two. There were no statistical differences in the first and third month serum and urine NO levels between patients who underwent bacillus Calmette-Guérin instillation therapy postoperatively and the patients who took chemotherapy or no further treatment. Both local and generalized host defense mechanisms seem to function in bladder cancer patients. Although further evaluation with a longer observation period and larger numbers of patients is necessary, results suggest that serum and urine NO levels are not putative and useful markers for bladder cancer.