The effect of repeated BCG vaccine administration associated with surgery upon the growth of lung metastases in rats with transplantable Morris 5123 hepatoma.

Eighty four male Buffalo rats bearing transplantable Morris 5123 hepatoma were used for the experiment. Half of the animals were given into the tumor BCG vaccine (final dose 2.2 X 10(6) living mycobacteria), the other 42 rats after BCG underwent surgical removal of the hind leg together with the tumor. Though the immunotherapy reduced the size of lung metastases of the tumor it did not, however diminish the survival rate of the animals. Multiple BCG doses associated with the surgical procedure prevented dissemination of the tumor cells and prolonged the survival of rats up to the 100th day of the follow-up.