Tumor stem or progenitor cells are isolated from samples taken from tumor fluid biopsies or by pasteurized brushing, and these cells are then placed in a culture environment containing a specific extracellular matrix (e.g., Matrigel), with the addition of appropriate growth factors (Borrell, 2010), while a suitable combination of growth factors, such as epidermal growth factor (EGF) and fibroblast growth factor (FGF), is added to promote organoid formation and growth. This evidence concerns the gene EGF and neoplasm.