Influence of intravesical bacillus Calmette-Guérin therapy on systemic immunological status.

Abstract

Intravesical bacillus Calmette-Guérin (BCG) therapy for superficial bladder cancer induces obvious local immunological responses. The purpose of this study was to examine the systemic immunological influences induced by intravesical BCG therapy. We measured peripheral blood lymphocyte subsets (PBLS) and monocyte counts in 30 patients with superficial bladder carcinoma by two-colored flow cytometry before, during, and after intravesical BCG treatment. Comparisons were made between 24 good treatment responders and 6 poor responders. From 3 to 12 months after the beginning of treatment, PBLS and monocyte counts changed, as evidenced by an increase of suppressor T cells and a decrease of helper T cells. The good responders had higher cell counts than the poor responders, with differences in cell counts between good and poor responders more marked 1 month after beginning treatment, particularly of natural killer cells, cytotoxic T cells, and inducer T cells. These differences disappeared 3 months after the onset of treatment. Intravesical BCG therapy caused a marked and persistent alteration of the systemic immunological status.