Much research has been done on new treatment modalities for patients with metastatic castration-resistant prostate cancer (mCRPC) but the cross resistance between these therapies needs to be understood better.
Another relative new topic of research is the quality of life (QoL) for patients receiving androgen-deprivation therapy (ADT). Dr. Robert van Soest (NL) gave an up-to-date overview of data on potential predictive biomarkers which may reveal the mechanisms of cross resistance. He said AR-V7 expression in circulating tumour cells is associated with primary cross resistance in abiraterone and enzalutamide, but not in treatment with taxanes.
An elevated neutrophil to lymphocyte ratio (NLR) may be related to lower PSA response in men treated with abiraterone but it appears to not have any predictive value for patients treated with taxanes. NLR is readily available and cheap and Van Soest argued that it should be included in prognostic nomogrammes and could be used for risk stratification in clinical trials.
Gleason score and duration of initial ADT may also be considered in treatment selection for mCRPC patients. Van Soest: “There is an urgent need for prospective, large-scale studies so that we can change the one-size-fits-all treatment for men with mCRPC into a personalised approach.”
Mr. Derek Rosario (GB) talked about the important issue of QoL for patients treated with ADT. As session chairman Prof. Bertrand Tombal (BE) pointed out: “Hormonal therapy is no sugar pill; QoL matters.” Rosario mentioned that although QoL is a very individual concept, there are scientific measures to study it. “Unfortunately, there aren’t many studies out there yet,” Rosario said before going through available data.
It is clear that androgen withdrawal results in non-beneficial effects and limiting exposure to ADT will improve QoL. Pharmaceutical interventions can improve adverse events but there are no data on whether or not this improves QoL.
Exercise or physical activities have shown to have a positive impact on fatigue, a common side effect. None of the other domains showed to be affected by exercise and long-term patient adherence is a problem. Discussing the possible impact of treatment on QoL and other forms of patient education are beneficial for patients’ expectations and a doctor-patient dialogue is important.