[Oligometastases and oligoprogressions: Concepts and natural history]

The oligometastatic paradigm refers to an intermediate biologic state of cancer with restricted metastatic capacity. Its phenotype is characterized by a limited number of metastases and a slow tumor growth. Various clinical and pre-clinical studies associated this state to alterations of the biological mechanisms involved in metastatic diffusion. Eventually, this transitional state leads to a wide metastatic dissemination. However, there is a period during which the patient could benefit from local ablative treatment. Depending on several prognostic factors and the treatment provided, long survival or even healing can sometimes be achieved. The selection of patients eligible for such a curative strategy may be adapted following clinical, radiological or biological markers. Recent improvement of therapeutic and imaging are changing the clinical definition of oligometastatic cancer, which should be adapted to evidence from recent clinical and preclinical data.