Since the approvals for the early use of docetaxel chemotherapy (Taxotere) and the early use of abiraterone acetate (Zytiga) there is no clear evidence demonstrating which of these two agents should be used for men with hormone sensitive, newly diagnosed, aggressive prostate cancer.
This is a real problem made worse because at this time there are no new randomized clinical trials scheduled comparing these two treatment options, other than PEACE 1.
The STAMPEDE Trial, the only currently completed trial for men at this stage of prostate cancer showed that when you evaluate men on ADT plus abiraterone (Zytiga) versus ADT plus docetaxel. (Taxotere) there isn’t any significant difference in overall survival (OS) or metastasis-free survival (MFS) between these two groups.
STAMPEED did see a difference favoring the abiraterone group for progression free survival (PFS), but PFS is just a surrogate endpoint. What is important is that for the primary endpoints, OS and MFS there was no difference between the two groups.
It is anticipated that in 2020 we will have data from the PEACE1 trial which is being conducted in Europe. In that clinical trial, there is going to be a direct comparison with adequate power to answer the question, Is abiraterone plus ADT or docetaxel plus ADT better?
Until that time we will need to rely on the experience of our doctors to assist us in deciding which treatment might be better for each individual. Cancer ABCs has spoken with a few different oncologists about how they advise their patients when facing this decision.
We found that there is a consistency among the doctors. Most doctors evaluate their patient’s comorbidities, their age, disease volume and their performance status.
The consensus is that abiraterone (Zytiga), is more appropriate for older men, those with poor performance status, and also men with low-volume disease—which is defined differently in different cohorts, but not having any visceral metastases, but at least 3 boney metastases.
In contrast, docetaxel is preferred in younger men, men with good performance status, and those with high-volume disease. CHAARTED found that men with low-volume disease did not benefit from docetaxel; only those with high-volume disease benefitted, thus only men with high-volume disease should be offered docetaxel.
Additionally, Docetaxel has a number of significant toxicities that should limit which men should take it; men with significant peripheral neuropathy, those who would have trouble with myelosuppression, or who are at an increased risk of infection from other comorbidities probably should not take docetaxel because it will cause all of these side effects.
Joel T. Nowak, MA, MSW wrote this Post. Joel is the CEO/Executive Director of Cancer ABCs. He is a Cancer Thriver diagnosed with five primary cancers - Thyroid, Metastatic Prostate, Renal, Melanoma, and the rare cancer Appendiceal cancer.