Episode 20: Dose-escalated radiotherapy with or without short-term ADT for patients with intermediate-risk prostate cancer

In this new episode of ‘What’s New Doc’ in Prostate cancer, Prof Bertrand Tombal from the Cliniques Universitaires Saint-Luc in Brussels, and Prof Steven Joniau from the University Hospitals Leuven discuss the results of a phase III, randomized-controlled trial evaluating the added value of androgen deprivation therapy (ADT) in patients with intermediate-risk prostate cancer receiving dose-escalated radiotherapy (RT).¹

In this study, a total of 1,492 patients with intermediate-risk prostate cancer (i.e., stage T2b-T2c, Gleason score 7, PSA >10 and ≤20 ng/mL) were randomly assigned to receive dose-escalated RT alone or in combination with short-term ADT (6 months). After a median follow-up of 6.3 years, no significant difference was seen between both arms in terms of overall survival (HR[95%CI]: 0.85[0.65-1.11]). In contrast, the addition of short-term ADT did lead to an improvement in the rate of PSA failure (HR: 0.52]; p< 0.001), the incidence of distant metastases (HR: 0.25; p< 0.001) and prostate-cancer specific mortality (HR: 0.10; p= 0.007).¹

For Prof Tombal, these findings reaffirm that too much hormone therapy is being used in patients with intermediate-risk prostate cancer. He beliefs that we need to move away from the automatic use of 6 months of ADT in this setting and urges for a better refinement of the treatment strategy. Prof Joniau agrees and underscores that intermediate-risk prostate cancer remains to be a poorly defined, heterogenous group of cancers, with a variable prognosis. In addition to specific disease characteristics, also patient-related factors (e.g., cardiovascular risk, diabetes, life expectancy of the patient, etc.) need to be considered in multidisciplinary discussions on the need for ADT in patients with intermediate-risk prostate cancer. In this respect, the Omega score calculator can be a valuable tool to determine the potential added benefit of ADT.²