Purpose: Interleukin (IL)-2 and interferon-gamma are released during T helper 1 lymphocyte responses, while IL-10 is released during T helper 2 responses. We evaluated the prognostic value of urinary IL-2, interferon-gamma and IL-10 levels in patients with superficial bladder cancer treated with bacillus Calmette-Guerin (BCG) instillation.
Methods: Urinary IL-2, interferon-gamma and IL-10 were measured by enzyme-linked immunosorbent assay in 37 patients receiving BCG for stages Ta/T1 superficial bladder cancer, and carcinoma in situ. Measurements were made after instillations 5 and 6 during a course of 6 weekly instillations of 150 mg. BCG, Pasteur strain. Correlations of cytokine levels with the clinical outcome were evaluated using the log rank test.
Results: Median followup was 29 months. Patients with urinary IL-2 less than 27 pg./micromol. creatinine were significantly more likely to have recurrences than those with higher values (log rank test p = 0.0009). Urinary IL-10 and interferon-gamma levels had no apparent impact on the risk of recurrence or progression.
Conclusion: Urinary IL-2 levels may serve to identify patients at risk for bladder cancer recurrence after a single course of BCG and, thus, to tailor individual treatment.