Pan C-W et al. (2008) The effect of intravesical instillation of antifibrinolytic agents on bacillus Calmette–Guérin treatment of superficial bladder cancer: a pilot study. J Urol 179: 1307–1312

Superficial bladder cancer does recur despite bacillus Calmette–Guérin (BCG) instillations—currently the most effective prophylactic therapy. Antifibrinolytic agents seem to enhance the efficacy of BCG instillation, but their systemic administration is contraindicated in individuals with increased cardiovascular risks—especially middle-aged and elderly people, who also have increased risks of bladder cancer. Pan and colleagues, therefore, investigated whether intravesical instillation of antifibrinolytic agents with BCG might retain the antitumor effects without prolonging blood clotting times.

This pilot study included 257 consecutive patients (median age 58.5 years, 180 men) treated at two Chinese hospitals. Patients were randomly allocated to one of five groups, which all received different treatments: 100–120 mg or 50–60 mg BCG, plus either 100 mg para-aminobenzoic acid or 2.0 g epsilon aminocaproic acid, or 100–120 mg BCG alone. All instillations were retained for 2 h. Tumor recurrence was assessed cystoscopically every 3 months during follow-up (median 25 months).

Unfortunately, the study suffers from a surfeit of variables. These authors' analysis would be clearer and more useful had they separated the dose-ranging study from investigation of this treatment's feasibility and efficacy, and if they had not confused the picture further by using two different antifibrinolytic agents. Nonetheless, significantly more recurrences occurred in the BCG-only group than in any combination-therapy group, even the low-BCG-dose groups. Clotting times (at 2 h post-treatment) and adverse-event rates were similar across all groups. Further investigation to confirm these findings is warranted.