Characterisation of the 143B locally metastasising model. This model can be used for testing of the antimetastatic properties of candidate therapeutic agents against osteosarcoma. 143B cells were injected into the inguinal fatpad of mice. A, palpable tumour at 2 weeks post-injection, B, exposed tumour at 2 weeks post-injection, C, clearly discernible tumour at 4 weeks, D, exposed tumour at 4 weeks, E, white arrowhead indicates site of primary tumour, black arrowhead indicates site of secondary locoregional tumour, F, arrowhead, site of locoregional tumour metastasis, G, arrowhead, pulmonary metastasis within lung parenchyma. Scale bar = 25 μm.