Urinary fibronectin levels in patients treated with intravesical bacillus Calmette-Guerin for superficial bladder cancer

Intravesical bacillus Calmette-Guerin (BCG) has been shown to be an effecti ve treatment for superficial transitional cell carcinoma (TCC) of the bladd er, but the precise mechanism of action of BCG remains poorly understood. F ibronectin (FN), an important component of the extracellular matrix, has be en found to play a role in BCG therapy. Some studies have shown that the so luble form of FN can compete efficiently with the matrix form of binding to the specific receptors on the bacteria and could consequently diminish the effect of BCG treatment. To evaluate a possible correlation between the ur inary levels of FN and the efficacy of BCG the ra py, we determined prospec tively the urinary FN levels in 38 patients with TCC of the bladder and in 25 control subjects without malignancy matched for age and sex. All TCC pat ients were treated with transurethral tumor resection plus 6 weekly intrave sical BCG instillations. After an average follow-up of 30 months, 8 patient s (21.1%) had recurrent tumors, while 30 (78.9%) were free of tumor after i ntravesical BCG therapy. Urinary levels of FN in cancer patients have been shown to be significantly higher than controls (p < 0.001). These elevated levels were not decreased significantly after the operation (p > 0.05). It was also found that the mean urinary FN levels were not statistically signi ficant between patients with recurrence and complete remission. The data su ggest that BCG-bladder tumor cell binding is not influenced by soluble fibr onectin and urinary FN may not be a ideal marker for selecting patients to BCG therapy, Copyright (C) 2000 S. Karger AG, Basel.