Review of literature shows that it is possible to establish tumor-derived organoids, or tumoroids, from almost any type of tumor, and that these "micro-tumors" could be used to develop functional assays allowing the prediction of the patient response to treatments and/or the identification of predictive molecular signatures associated with the development of these therapies. Although it is still essential to optimize culture conditions to promote and accelerate the establishment of tumoroids, or to recapitulate tumor microenvironment, many applications are now possible in the field of prediction of response to treatments and in guiding therapeutic decision-making. Using tumoroids as standard tools in clinical oncology could make precision oncology enter a new era in the coming decade. Numerous ongoing research and clinical trials conducted throughout the world aim to validate the interest of this approach.