Therapy of spontaneous pulmonary metastases of a murine mammary carcinoma with anaerobic corynebacteria

Corynebacterium parvum given intravenously or into the tumor 7 or 2 days before surgical removal of primary tumors greatly reduced the number of spontaneous pulmonary metastases of a syngeneic mammary carcinoma of C3Hf/Bu mice. When a single dose of 6000 rads γ-rays was used to eliminate primary tumors the number of lung metastases significantly increased. Administration of C. parvum before irradiation not only prevented this metastasis - facilitating effect of radiation, but also reduced the number of lung nodules below that in amputated mice. Metastatic spread was not altered by postoperative treatment of mice with single doses of C. parvum or C. granulosum. However, significantly more mice had lung metastases if they were given 2 intraperitoneal injections of C. granulosum.