Objective: Intercellular adhesion molecule-1 (ICAM-1) is known to play a role in immunity against bladder cancer and can be detected in the supernatants of cultured bladder cancer cells that constitutively express ICAM-1. This study was performed to examine the relevance of the ICAM-1 urine test in patients with bladder cancer.
Methods: A total of 53 patients with bladder carcinoma, 35 with history of bladder cancer, and 30 normal control subjects were included in this analysis. Urinary ICAM-1 (ulCAM-1) levels were measured by immunoassay and corrected for hydration status.
Results: Levels of ulCAM-1 were significantly elevated in patients with bladder cancer or those at tumor-free status compared with normal control subjects (P=0.001). However, there was no apparent difference between the two groups of urothelial disorders (P >0.1). ulCAM-1 did not correlate with clinicopathologic variables of bladder cancer or patient outcome (P >0.1). Six patients at tumor-free status had multiple ulCAM-1 determinations during the study period. Three of these 6 patients had elevated ulCAM-1 levels and proved to have recurrent tumors; 3 of the 6 had stable ulCAM-1 levels and were still free of disease.
Conclusions: Our results suggest that urinary excretion of ICAM-1 is elevated in the early stage of bladder carcinogenesis, but is independent of biologic properties of bladder cancer. Serial monitoring of ulCAM-1 may be helpful in selecting patients who are at risk of tumor recurrence.