We designed a brief questionnaire and sent it to the members of the Society of Urologic Oncology. We received a total of 119 responses, mostly staff with a significant number of patients with prostate cancer in their practice. Despite the growing literature supporting the use of different PET-CT modalities, the great majority of the respondents did not recommend the use of such imaging for the definition of oligometastatic prostate cancer. Perhaps this is because of availability since such studies are not as widely available as conventional imaging (CT, bone scan, or even MRI). When asked about what would be considered a significant clinical benefit for their patients, most of the physicians considered that a “curing rate” beyond 10% would be a good outcome and a delay in the start of androgen deprivation therapy 1 year or more. Using the obtained answers, we modeled a sample size calculation for a hypothetical clinical trial that could serve for the design of future studies in this controversial stage of prostate cancer.
More studies are required to know if the benefit offered by the treatment of oligometastatic prostate cancer is clinically significant, but perhaps before we are able to do that, we should try to focus on unifying the definitions of the actual stage of the disease, as well as the desired outcomes.
Written by: Jaime O. Herrera-Caceres, MD, Division of Urology, Department of Surgical Oncology, University of Toronto and University Health Network, Toronto, Canada.
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