[A study of the mechanism of action of BCG against transitional cell carcinoma of the bladder--the change of TNF-alpha and IL-2 in the serum and urine].

To study the mechanism of action of BCG against transitional cell carcinoma of the bladder from the immunological standpoint, we observed time-course changes in the serum and urine levels of tumor necrosis factor (TNF-alpha) and interleukin-2 (IL-2) before and after an intravesical BCG instillation in 16 patients with superficialis transitional cell carcinoma. Serum TNF-alpha concentrations were roughly constant and lower than normal though there was a slight difference between the values before and after BCG instillation or between the test and control values. TNF alpha secretion in urine was increased irrespective of the time for sampling specimens as compared with the control values sampling, remained unaffected by BCG instillations and was increased in many patients even before BCG instillation, probably due to presence of vesical inflammation. No significant changes were detected regarding serum or urine IL-2 before and after BCG instillation and between the test and control values. Thus, the present study failed to demonstrate the involvement of a direct action of TNF-alpha, activation of immunological cells by IL-2 or its direct action as an anti-tumor effect of intravesical instillation of BCG.