Intravesical gemcitabine: a phase 1 and pharmacokinetic study.

INTRODUCTION: Superficial bladder cancer can be treated by transurethral resection and additional intravesical therapy. Although agents like Mitomycin C, Epirubicin and BCG are routinely used, there is a need for more potent and/or less toxic agents. Gemcitabine is a deoxycytidine analogue, used systemically for several tumours, such as non-localised bladder cancer, where it is effective and well tolerated. We investigated the use of three dose levels of gemcitabine when given intravesically in humans for safety and pharmacokinetic research. MATERIAL AND METHODS: Patients with superficial bladder cancer, except pT1G3 or CIS were included. Six weekly instillations of 1000, 1500 or 2000 mg gemcitabine were given in 50 ml saline for one hour. Dose modifications were defined in case of dose limiting toxicities. Blood samples were taken before, and 5, 30, 60 (= evacuation) and 120 minutes after instillations 1, 3 and 6. Samples were used for blood counts and pharmacokinetics. Side effects were noted. RESULTS: 3, 4 and 3 patients were treated with 1000, 1500, and 2000 mg gemcitabine respectively, of which 2, 3 and 1 patients had highly recurrent tumours before treatment. Seven patients experienced side effects: 2 with dysuria after the first instillation, 2 after instillations 3-6 and 4-6 and in 3 patients headache, fatigue and heavy legs were experienced once. All side effects were reversible, non-limiting and WHO 1. No macroscopic hematuria was seen. Haematology showed only one case of drop in white blood cell count (lowest dose level, after the first instillation). Gemcitabine plasma levels were immeasurable or low, with peak levels between 30 and 60 minutes, decreasing after more instillations. The metabolite difluorodeoxyuridine reached levels of at most 5 microM, indicating a very low passage of the drug to the systemic circulation. CONCLUSION: Intravesical gemcitabine in the dose used has minimal and reversible side effects. Plasma evaluation indicates that its intravesical use is safe.

Mycotic aneurysm of the popliteal artery as a complication of intravesical BCG therapy for superficial bladder cancer. Case report and literature review.

A 67-year-old man was treated with maintenance intravesical BCG for superficial bladder cancer. As a culture-proven complication of this therapy, he developed general malaise, high fever, granulomatous hepatitis and a mycotic aneurysm in his left knee. All complications were treated successfully with antituberculous therapy. No vascular surgery was necessary. This case report again stresses the necessity to recognise complications of BCG treatment and to start adequate therapy as soon as possible.

Pharmacokinetics of intravesical gemcitabine: a preclinical study in pigs.

INTRODUCTION: Gemcitabine is a deoxycytidine analogue, used intravenously in the treatment of several tumours, including transitional cell carcinoma of the bladder. It has been shown to be effective and well tolerated when given systemically. We investigated the use of this agent administered intravesically in pigs for histological studies of the bladder and pharmacokinetic research. MATERIAL AND METHODS: Two groups of 5 female pigs each received once 175mg and 350mg gemcitabine intravesically for 2 hours. A third group of 5 pigs received 350mg gemcitabine weekly for 6 weeks. Animals were observed for clinical signs of toxicity. Blood was withdrawn for gemcitabine pharmacokinetics and in group 3 also for peripheral blood counts. The animals were euthanized 24 hours after (the last) instillation. Histological examination of the bladder wall was performed. RESULTS: Doses of 175 and 350mg gemcitabine were well tolerated. The animals showed no signs of deterioration of their well-being. Peripheral blood counts showed no signs of immunosuppression in the third group. In none of the pigs systemic absorption was seen, up to 4 hours after the beginning of instillation. Histology showed in all cases normal bladder wall histology, except for some cases with mild signs of infection (mainly group 3). CONCLUSION: The use of gemcitabine as an intravesical agent in pigs is well tolerated, has no bladder toxicity and is not absorbed systemically.