Osteosarcomas in NZBR/BI mice

Osteosarcomas occurring in untreated and paraffin-treated NZBR/BI mice are described. Tumour tissue from one paraffin-treated animal was propagated by subcutaneous transplantation into young syngeneic male mice and the growth pattern and histological appearance of successive transplants were studied. The ability to form bone was retained and a propensity for metastasis to the lungs was observed. The latent period between the time of transplantation and clinical evidence of tumour formation diminished as passaging proceeded but there was no enhancement of the transplantability of osteosarcomas. The incidence of osteosarcomas in NZBR/BI mice is compared with that observed in other strains of mice.