Dr Ravi on the Investigation of RCB Following ARPI Treatment in High-Risk Prostate Cancer

Praful K. Ravi, MB, BChir, MRCP, medical oncologist, Lank Center for Genitourinary Oncology, medical director, GU Theranostics, Dana-Farber Cancer Institute, instructor, medicine, Harvard Medical School, discusses the rationale for a study evaluating the prognostic impact of residual cancer burden (RCB) on long-term outcomes after neoadjuvant androgen receptor pathway inhibitor (ARPI) and radical prostatectomy (RP) in patients with high-risk localized prostate cancer (HRLPC).

This study focused on patients receiving neoadjuvant therapy before surgery for high-risk prostate cancer, a practice not yet considered standard of care, Ravi begins. Multiple trials have been conducted using ARPI as neoadjuvant treatment for patients with high-risk disease. Investigators pooled data from patients across 5 of these trials to assess their long-term outcomes, particularly focusing on metastasis-free survival (MFS), which is a known surrogate for overall survival in this context, according to Ravi. Previous reports have primarily concentrated on early end points, such as pathologic outcomes, so this analysis aimed to provide insight into the long-term effects of residual disease after surgery and its potential prognostic significance, he reports.

The study included 218 patients from these 5 randomized neoadjuvant trials, with a median follow-up period of approximately 5 years, Ravi continues. The patients received treatment for 6 months prior to undergoing surgery. All patients underwent a central pathology review to assess the extent of residual disease post-surgery, he states. The key focus of this study was on evaluating the pathological response and the amount of residual disease, leading to the calculation of RCB, Ravi explains. This metric is similar to what is used in patients with breast cancer after neoadjuvant chemotherapy, Ravi notes. Investigators correlated RCB with long-term outcomes, specifically looking at MFS—defined as the time until patients developed metastasis or died from the disease post-surgery, Ravi emphasizes.

This analysis sheds light on the potential prognostic value of measuring residual disease following neoadjuvant therapy, offering insights that could influence future treatment strategies for HRLPC, he concludes.