Local treatment for metastatic prostate cancer: A systematic review

The potential oncological benefit for radical treatment in the setting of oligometastatic prostate cancer has been under investigation and is frequently discussed. We carried out a systematic review of English language articles using the Medline database (January 2000 to May 2017) to identify studies reporting local treatment in men with metastatic prostate cancer at diagnosis. Primary end-points were oncological outcomes, such as cancer-specific and overall mortality. Secondary end-points were non-oncological outcomes, such as complications, operating room time, blood loss or length of hospital stay. Two independent authors reviewed and extracted all search results. Overall, 18 studies reporting on local treatment in metastatic prostate cancer patients were identified (14 original articles, three brief correspondences and one letter to the editor). All of them were retrospective; one partly included prospective data. All studies addressed oncological outcomes, 16 compared local treatment with no-local treatment and 14 adjusted for confounders using multivariable regression models. All but one study concluded a survival benefit for local treatment in the metastatic setting. Due to heterogeneity of available data, a representative meta-analysis could not be carried out. Five studies reported non-oncological outcomes. Although local treatment in metastatic prostate cancer appears to be feasible, its oncological effect remains unclear due to high susceptibility of available studies to significant selection bias.