Low-Grade, Multiple, Ta Non-muscle-Invasive Bladder Tumors: Tumor Recurrence and Worsening Progression

Nearly half of newly diagnosed cases of bladder cancer are low grade, noninvasive, and papillary tumors. The standard treatment for non-muscle-invasive bladder cancer (NMIBC) has been transurethral resection of the bladder tumor (TUR-BT) with or without adjuvant intravesical instillation (IVI) of chemotherapy or Bacillus Calmette-Guerin (BCG) therapy. NMIBC is known to be associated with high rates of recurrence and risk of progression. In this study, we have retrospectively analyzed the clinical outcome of initially diagnosed multiple low-grade Ta tumors, with a special focus on tumor recurrence and worsening progression (WP) pattern. We retrospectively reviewed 42 patients with primary, multiple, low-grade Ta bladder cancer. We defined WP as confirmed high-grade Ta, all T1 or Tis/concomitant CIS of bladder recurrence, upper urinary tract recurrence (UTR), or progression to equal to or more than T2. The associations between clinico-pathological factors and tumor recurrence as well as WP pattern were analyzed. Tumor recurrence and WP occurred in 23 (54.76%) and 8 (19.04%) patients during follow-up (median follow-up: 57.38 months), respectively. WP to high grade/stage was seen in 8 patients. Multivariate analysis demonstrated that use of tobacco (p < 0.0001) and absence of IVI (p < 0.0001) were significant risk factors for tumor recurrence. The 5-year recurrence-free survival rate for non-tobacco users (74.0%) was significantly higher than that for tobacco users (42.5%, p = 0.0001), and also higher for patients receiving intravesical instillation (84.2 vs. 30.0% without IVI, p = 0.0001). Recurrence is common in patients with low-grade, Ta bladder cancer, especially in the setting of multiplicity. Recurrences occurred in 54.76% of patients and WP occurred in 19.04% of patients. Use of tobacco and non-use of IVI were strongly associated with high recurrence rate.