Heterologous Growth of Sarcoma 180 with Progression to Death of Hosts^*

It has been possible to make serial passages of the mouse tumor Sarcoma 180 in the newborn rat by utilizing the intraperitoneal route of inoculation. Subcutaneous inoculations of newborn rats and a transplant of the same tumor in older animals generally failed to grow or regressed after a short period. When inoculated into 1-2-day-old rats, the Sarcoma 180 generally brought about the death of the animal in a week, often with widespread metastases.