Emerging targets in prostate cancer

An update on prostate cancer was presented at the Gathering Around Cancer Conference by Dr Niamh Keegan of Memorial Sloan Kettering Cancer Centre, New York, US. Dr Keegan explained that prostate cancer treatment is a fast-evolving field with regular updates, and she focused on antigen-receptor (AR) prostate cancer during her talk. In addition to managing the AR pathway, Dr Keegan also discussed the role of immunotherapy and the increasing role of radioiodine therapy in prostate cancer.

“The landscape for prostate cancer is proliferating with treatment options,” Dr Keegan told the conference. “Relatively uniquely in the world of solid tumours, we see prostate cancer in the advanced setting very much defined by its treatment with hormone therapy, which is the mainstay of treatment throughout the course of the disease, and we develop around that in terms of combinations.”

Dr Keegan explained that prostate cancer is a hormone-derivative disease, particularly at the start of its course. Since the 1940s the mainstay of treatment has been testosterone-lowering therapy. “We know that testosterone therapy increases the level of frailty in our patients over time, and it’s worth thinking about what that does as we move towards using it earlier in the course of our treatments.”

In this changing treatment landscape, it has been discovered that AR therapy resistance emerges within the AR pathway and the addition of further targeted AR therapies can overcome that, said Dr Keegan. “This can be done by reducing the synthesis of testosterone outside the testes, or by blocking the testosterone receptor with a variety of agents. We have an abundance of options in this space, all of which are proven to extend overall survival, and none of which have been compared to each other.

“The choice of treatment is essentially a clinical choice based on the patient’s psychosocial needs, and clinical data about the prostate cancer itself,” she continued.

“This is nothing more elaborate than their PSA production, their Gleason score, and their staging at time of diagnosis.”

Dr Keegan briefly discussed upcoming trials that provide hope for improved outcomes. She also said better tools are required for treatment selection, depending on metastases, high-volume disease, and other clinical factors.

However, she concluded that “this is an exciting time for emerging targets in prostate cancer, with expanding therapeutic mechanisms. The transition of the science and the main points in recruitment in our trials are worthy points for consideration on how we might better design these trials and recruit patients over time and to best deliver these scientific developments to our patients in a timely and cost-effective manner.”