Metastatic Hormone-sensitive Prostate Cancer: Current Perspective on the Evolving Therapeutic Landscape

INTRODUCTION: The treatment landscape for patients with metastatic hormone-sensitive prostate cancer (mHSPC) has changed dramatically in the past five years, despite little change in the preceding 20 years. Such rapid change can make it difficult for clinicians to remain abreast of the current literature and synthesize the relevant data to inform evidence-based treatment decisions. METHODOLOGY: We performed a narrative, comprehensive review of treatment options for patients with mHSPC as of December 31, 2019. Specifically, we focused on phase II and III randomized controlled trials assessing the role of chemotherapy, novel androgen axis targeting agents, local-(prostate) directed therapy, and metastasis-directed therapy. RESULTS: The data support a survival benefit with the addition of four different agents to androgen deprivation among men with newly diagnosed prostate cancer—docetaxel, abiraterone acetate, enzalutamide, and apalutamide. While not directly compared, the efficacy of these agents appears similar. That said, there are differences in their toxicity profiles and notable differences in cost between agents. Although analyses encompassing men with low- and high-volume metastases failed to demonstrate a significant survival benefit for radiotherapy treatment to the prostate, new data demonstrates a benefit for men with low-volume metastatic disease. Ongoing trials will assess whether this applies to local surgical treatment. Similarly, metastasis-directed therapy appears beneficial among carefully selected patients. CONCLUSION: Treatment options for patients with mHSPC are rapidly changing following years of stagnation. A number of systemic therapies offer benefit without significant clinical differences between them. The role for local treatment of the prostate as well as metastatic sites continues to evolve.