Purpose. To study GP-170 in superficial bladder cancer at initial diagnosis and at recurrence and to evaluate if intravesical chemoprophylaxis modifies the expression of GP-170 in tumor recurrence. Materials and Methods. GP-170 was retrospectively assessed in 160 patients affected by primary superficial transitional cell carcinoma of the bladder and followed for up to 10 years. Eighty-four patients (52.5%) recurred after transurethral resection (TUR). Adjuvant intravesical chemotherapy after TUR was adopted in 52 patients. The correlations between GP-170 expression and G-grade and T-category was found. A significant correlation was detected between GP-170 levels were also associated with an increasing risk of recurrence. Intravesical chemotherapy did not induce significative variations in GP-170 expression. No correlation was found between progression and GP-170. Conclusion. GP-170 seems to be an independent prognostic factor for recurrence in superficial bladder tumors. A negative GP-10 pattern and high levels of GP-170 are associated with an increasing risk of recurrence but have no impact upon progression. In our experience, GP-170 is neither induced nor modified by intravesical chemotherapy, although it might represent a factor of chemoresistance when strongly expressed.