Pathlicon 1 article published in JoVE Medicine The In ovo CAM-assay as a Xenograft Model for Sarcoma Gwen M.L. Sys1, Lore Lapeire2, Nikita Stevens1, Herman Favoreel3, Ramses Forsyth4, Marc Bracke2, Olivier De Wever2 1Department of Orthopaedic Surgery and Traumatology, Ghent University Hospital, 2Department of Radiation Oncology and Experimental Cancer Research, Ghent University, 3Department of Virology, Parasitology, and Immunology, Ghent University, 4Pathlicon The in ovo chorioallantoic membrane (CAM) is grafted with fresh sarcoma-derived tumor tissues, their single cell suspensions, and permanent and transient fluorescently labeled established sarcoma cell lines. The model is used to study graft- (viability, Ki67 proliferation index, necrosis, infiltration) and host (fibroblast infiltration, vascular ingrowth) behavior.