Analysis of drug sensitivity of human high-grade osteosarcoma in a chick chorioallantoic membrane (CAM) model: a proof of principle study.

Multi-agent chemotherapy is an important pillar in treatment of high-grade osteosarcoma. In an effort to improve patient survival, it is imperative to determine the effectiveness of new substances. The objective of this study was to investigate whether the chick chorioallantoic membrane (CAM) model can be used to analyze drug sensitivity in high-grade osteosarcoma. Spare biopsy tissue from five patients diagnosed with high-grade osteosarcoma was transferred into non-immortalized primary cell culture. After a pre-incubation period of 10 days, fertilized chick eggs were inoculated with primary tumor cells suspended in extracellular matrix gel. On day 16, treatment with 20 µmol/l doxorubicin (n = 4) or 25 µl of culture medium (n = 6) was performed for 24 h. CAM membranes were documented macroscopically, harvested and examined histologically. Transfer of biopsy specimens into primary cell culture was successful in all cases. 50% (n = 10) of eggs died after inoculation with tumor cells and before application of doxorubicin. No deaths occurred after application of doxorubicin. Histological examination found a response to doxorubicin in all four specimens. Based upon these results, the CAM model represents a promising preclinical alternative to animal experiments to determine drug sensitivity of osteosarcoma cells. Further research with regard to other substances and dosages appear justified.