Background and objectives: One of the current challenges in clinical oncology is the identification of patients with superficial transitional bladder carcinoma (TBC) at high risk of recurrence or myoinvasive disease. Recently, inducible nitric oxide synthase (iNOS) expression was detected in urinary bladder cancers. Because iNOS produces a high concentration of nitric oxide (NO), we thought it possible that urine from TBC patients produces high levels of NO. The aim of this study was to determine urine NO levels in TBC compared with healthy controls and with patients bearing other nonrelated tumors, as well as to examine iNOS expression in bladder cancer tissue.
Methods: This study evaluated patients with TBC (n = 33), with gynecological tumors (GT) (n = 19), TBC patients with no evidence of tumor (no evidence of disease [NED]) (n = 19), and healthy subjects (n = 39). Urine NO levels were determined by Griess reagent, expressed as microM NO(2) (-)/100 mg creatinine.
Results: TBC patients produced significantly higher urine NO median values (4.2 microM; range, 2.1-91.6) than were produced by healthy individuals (2.1 microM; range, 0.4-4.9), by the NED group (1.7 microM; range 1.2-5.4), and by GT patients (2.0 microM; range, 0.8-58.1) (P = 0.000, Kruskal-Wallis test). iNOS was detected by Western blot in 52% (13/25) of bladder tumors examined.
Conclusions: Although a wider study is necessary, our results suggest that the enhanced NO levels could perhaps be considered as a putative marker in TBC patients.
Copyright 2002 Wiley-Liss, Inc.