Prognostic value of urokinase-type plasminogen activator in patients with superficial bladder cancer

Objectives. A number of studies have demonstrated that urokinase-type plasminogen activator (u-PA) is one of the major enzymes in the development of cancer invasion and metastasis. We examined the possibility that u-PA content is an independent prognostic marker for superficial bladder cancer. Methods. The u-PA content was estimated in superficial bladder cancer from 52 patients undergoing transurethral resection for the first time. The survival rates of the patients were calculated and the prognostic values for u-PA content (less than 8 ng/mg protein versus more than 8 ng/mg), Stage (pTa or pT1), grade (1 and 2 versus 3), number (single versus multiple), and size (less than 1 cm versus more than 1 cm) of tumor were determined by a multivariate regression model. Results. Development of cancer invasion and metastasis was observed in 3 and 8 patients, respectively. The survival rate of the patients with high u-PA content was significantly lower than those with low u-PA content (P < 0.005), In the multivariate regression analysis, u-PA content was the most important risk factor for the prognosis, compared with the other factors: tumor stage, grade, multiplicity, and size. Conclusions. We have first shown that u-PA content is a new independent prognostic marker in patients with superficial bladder cancer.