Development of chondrosarcoma animal models for assessment of adjuvant therapy

Chondrosarcoma is a primary cancer of bone causing significant morbidity due to local recurrence and limited treatment options. Relatively few chondrosarcoma animal models have been developed, and the only orthotopic model is technically demanding and has limited clinical relevance. The aim of this review is to assess the features of current animal chondrosarcoma models for the purpose of developing new models in which to test adjuvant chondrosarcoma therapy. The available literature on this topic was identified using the PubMed database, and then analysed for relevance to the human chondrosarcoma disease and feasibility in testing new therapeutic agents. Animal-derived chondrosarcoma models comprise predominantly allograft tumour transplanted into the rat (Swarm rat chondrosarcoma) or the hamster. These types of models are less relevant to the human disease and have been more useful for evaluation of chondrosarcoma growth and histology than in developing novel therapeutic agents. The athymic nude mouse has enabled reliable human xenograft transplantation. A number of human chondrosarcoma cell lines have been successfully used to generate tumours in this species, including OUMS-27 and HCS-2/A. Although effective in demonstrating anti-tumour effects of a number of agents, the lack of a representative orthotopic model diminishes overall clinical relevance. More clinically relevant models of human chondrosarcoma progression are required either through transgenic mice or orthotopic human xenograft models.