Treatment of the Oligometastatic Patient

Oligometastatic disease (OMD) is an intermediate state between localized and disseminated cancer. Differently from polymetastatic disease in which systemic therapy is the mainstay treatment, patients with oligometastases may benefit from local treatments, possibly leading to cure. Evidence is emerging on the role of metastasis-directed treatment in improving quality of life and survival in the OMD state. Treatment of OMD should be decided in a multidisciplinary setting in which several factors are considered, including primary histotype, timing of OMD development (genuine versus induced, synchronous versus metachronous), involved metastatic sites (including number and size of lesions), and patient-related factors (including patient fitness and patient’s wishes). The most used modalities for metastasis-directed treatment are surgery, radiation therapy, and ablation, however each metastatic site has specific peculiarities. OMD represents a particular metastatic state that may benefit from metastasis-directed treatment. Further research is needed to identify which patients, histotypes, and metastatic sites might benefit from metastasis-directed treatment, and which are the most appropriate treatment options for each OMD state.