Background: Intravesical bacillus Calmette-Guerin (BCG) therapy has been proven to be effective in the prophylaxis and treatment of superficial bladder cancer. However, several complications of BCG therapy have been reported. The aim of this study was to clarify the impact of BCG treatment-related side effects on the clinical outcome of patients with superficial urothelial cancer.
Methods: We reviewed the medical records of 33 patients who underwent BCG instillation therapy in our department. After complete endoscopic tumor resection, intravesical or intrapelvic instillation of BCG (80 mg of the Tokyo strain) was performed every week for 8 weeks. BCG treatment-related side effects were classified as minor (persistence of symptoms or low-grade fever for less than 48 h) or major (persistence of symptoms or low-grade fever for more than 48 h, or high fever). Risk factors for major side effects and relationships between the occurrence of major side effects and subsequent tumor progression were evaluated.
Results: In total, there were 43 courses of intravesical and intrapelvic instillations of BCG in 33 patients, 20 (46%) of which were associated with major side effects. Risk factors associated with the occurrence of major side effects could not be detected. Subsequent tumor progression was observed in 3 of the 16 patients (19%) with major side effects and in 10 of the 17 patients (59%) without them. Nine patients who discontinued BCG therapy because of major side effects experienced no tumor progression. Progression-free survival was significantly higher in patients with major side effects than in those without them.
Conclusions: These results suggest that BCG therapy should be discontinued whenever major side effects occur, because this does not necessarily lead to an unfavorable outcome regarding tumor progression.