[Oligometastatic hormone-sensitive prostate cancer: when can less be more?]

With the use of modern imaging technology such as prostate-specific membrane antigen positron emission tomography-computed tomography (PSMA PET-CT), compared to conventional imaging with CT and bone scan, in the primary staging of localized prostate cancer and in the setting of PSA failure after local therapy, an increasing number of men are being diagnosed with metastatic prostate cancer with a low tumor burden. At the same time, the combination of androgen deprivation therapy (ADT) with androgen receptor pathway inhibitors (ARPI) has significantly improved the response rate and prognosis in metastatic hormone-sensitive prostate cancer. As a result, interest has in recent years grown in optimizing treatment for patients with low tumor burden by reducing treatment intensity. Strategies under evaluation include metastasis-directed therapy (MDT), intermittent systemic therapy and combinations of both. To date, no randomized phase 3 trials have demonstrated a benefit of either MDT alone or in combination to standard treatment, nor of intermittent strategies in oligometastatic prostate cancer. Nevertheless, experts consider the use of MDT as well as intermittent treatment with ADT + ARPI to be justified in selected cases. For clinical practice, it is important that treatment decisions adhere to the definition of oligometastatic disease (maximum of 5 metastases in bone or lymph nodes on PSMA PET-CT) and take into account the biology of the disease (synchronous vs. metachronous). The concepts of MDT and intermittent systemic therapy appear promising and patient participation in ongoing clinical trials is crucial.