No abstract

BACKGROUND: Osteosarcomas are a rare, heterogeneous and malignant group of bone tumors that have a high potential for metastasis and aggressive growth patterns. Treatment of metastasized osteosarcoma is often insufficient and research is compromised by problems encountered when culturing cells or analyzing genetic alterations due to the high level of intratumoral and intertumoral heterogeneity. The chick chorioallantoic membrane (CAM) model, a 3D-in-vivo-tumor-model, could potentially facilitate the investigation of osteosarcoma heterogeneity at an individual and highly specified level. OBJECTIVE: Objective was to establish the grafting and transplantation of different primary osteosarcoma tissue parts onto several consecutive CAMs for tumor profiling and investigation of osteosarcoma heterogeneity. METHODS: Various parts of primary osteosarcoma tissue were grafted onto CAMs and were transplanted onto another CAM for five to seven consecutive times, enabling further experimental analyzes. RESULTS: Primary osteosarcoma tissue parts exhibited satisfactory growth patterns and displayed angiogenic development on the CAM. It was possible to graft and transplant different tumor parts several times while the tissue viability was still high and tumor profiling was performed. CONCLUSIONS: Primary osteosarcoma tissue grew on several different CAMs for an extended time period and neovascularization of serial transplanted tumor parts was observed, improving the versatility of the 3D-in-vivo-tumor-model.

he wide field of microsurgery comprises surgical techniques that are characterized by the necessity of high-resolution surgical microscopes, magnifying glasses, and filigree surgical instruments to ensure precise handling of delicate tissue structures. Microsurgical methods are used in various disciplines, including plastic reconstructive surgery, 1 hand surgery, 2 maxillofacial surgery, 3 orthopedic surgery, 4 vascular surgery, 5 ophthalmology, 6 otorhinolaryngology, 7 urology, 8 and neurosurgery. 9 It is important to note that the performance of microvascular anastomoses strongly differs from conventional suturing practices; skills can hardly be obtained without specific training. 10 Basic microsurgical techniques, such as the implementation of vascular anastomoses and nerve coaptations, are performed in training courses in a variety of models. [11][12][13][14][15][16]