Experimental intraprostatic injection of bacillus Calmette-Guerin: a feasibility and safety study

We investigated the feasibility and safety of intraprostatic administration of bacillus Calmette-Guerin (BCG) and determined the histological changes induced by this approach.

A total of 36 healthy male beagle dogs 2.2 to 3.6 years old weighing 10.0 to 14.8 kg were randomly assigned to 6 experimental groups. Four groups were given intradermal BCG vaccination and 6 weeks later they were given 0 (group 1), 10 (group 2), 5 x 10 (group 3) or 10 (group 4) BCG organisms intraprostatically. An additional group received prevaccination, followed 6 weeks later by a dose of 10 BCG organisms intraprostatically and then 6 weeks of antibiotics (group 5). Another group receiving no prevaccination and 5 x 10 BCG organisms intraprostatically at week 6 were included (group 6).

Adverse reactions (ARs) were seen in 12 dogs, including inguinal lymphadenopathy in 3, an anal lesion in 5, constipation in 7 and dysuria in 3. There was a trend toward an increased incidence of ARs in high dose groups 3 and 4, fewer ARs in group 5 and no ARs in group 6. There was minimal evidence of systemic dissemination of BCG in any group. Post-necropsy histological analysis indicated higher inflammation as well as glandular destruction in high dose groups 3 and 4. Antibiotics did not seem to lessen the histological response to intraprostatic BCG injection (group 5). Interestingly in nonvaccinated group 6 the level of inflammation as well as glandular destruction was higher.

Our results indicate that intraprostatic BCG administration in dogs is a safe and well tolerated procedure. It is free of major or long lasting serious complications.