Ex vivo tumor culture is a cutting-edge technique involving the cultivation of live tumor tissues or cells outside the organism under conditions that closely mimic the tumor's original environment. This method preserves the tumor's natural architecture, cellular diversity, and microenvironment, maintaining the complex interactions between cancer cells and their surroundings—crucial for advancing cancer research, drug development, and personalized medicine. 

Common ex vivo tumor cultures include precision-cut tumor slices, patient-derived tumor explants, organoids, tumor spheroids, and microfluidic models. These platforms enable the study of key aspects of tumor biology, such as growth dynamics, tumor-stroma interactions, angiogenesis, immune evasion, and metastasis mechanisms. By preserving the integrity and heterogeneity of tumor tissue, ex vivo cultures provide more accurate predictions of drug efficacy for individual patients, guiding personalized treatment strategies. They are increasingly utilized in preclinical drug testing, including chemotherapy, targeted therapies, and immunotherapies. 

Despite its potential, ex vivo tumor culture faces challenges, including limited lifespan, tumor heterogeneity, and technical complexity, which can restrict its applications. This Methods Collection will focus on, but is not limited to, the following aspects of ex vivo culture: 

• Tumor sampling, preparation, and preservation 
• Culture conditions such as media optimization, improved oxygenation, and extended culture duration 
• Drug treatment and analysis using viability assays, high-throughput platforms, and studies on drug distribution and resistance 
• Monitoring tumor behavior through genomic and transcriptomic analysis, live imaging, and biomarker expression 
• Personalized medicine approaches addressing tumor heterogeneity and multi-omics integration 
• Promoting standardization and reproducibility through quality control measures