Which people with metastatic prostate cancer benefit most from upfront docetaxel?
New results from our first STOPCAP M1 individual participant data meta-analysis have been published in The Lancet Oncology and show that adding docetaxel to hormone therapy is more beneficial for some people with advanced prostate cancer than others.
Docetaxel was more effective for people who had metastases in organs including their liver or lungs, or at least 4 bone metastases (“high-volume” disease). Potentially, the benefit was even greater if they also had a large tumour in their prostate, with 55 out of 100 people who received docetaxel and hormone therapy alive after 5 years compared with 20 out of 100 who received hormone therapy only.
People who developed fewer than 4 bone metastases (“low-volume” disease) after being diagnosed with localised prostate cancer, did not benefit at all from docetaxel. At 5 years, 72 out of 100 were alive whether they received docetaxel or not. Such patients could be treated differently and spared the significant side effects of docetaxel.
These results can help inform decisions around the use of upfront docetaxel in people with metastatic, prostate cancer that is still responding to hormone therapy.
Dr Hayley Luxton, Research Impact Manager at Prostate Cancer UK, said: “We’re very excited about this research which shows how we can make existing treatments more personalised, and more effective. But what’s really important is that this now changes practice, and men with prostate cancer can start to benefit from these smarter ways of treating the disease. That’s why we fund research in the first place and it’s why we’re working with the government to make sure this is rolled out across the NHS.”
Previously, clinical trials had shown that adding docetaxel chemotherapy to hormone therapy can improve survival of people with advanced prostate cancer. However, there was uncertainty about who benefited most, and therefore how best to use it, especially given that other life-prolonging therapies are available.
To address this, the STOPCAP team included the three largest trials of docetaxel in a meta-analysis. These include data on 2261 people, 98% of all patients who had ever taken part in similar trials. Having individual participant data from so many participants allowed the us to look at who benefits from docetaxel in more detail and more reliably than previous studies.
Professor Jayne Tierney, who led the research at the MRC Clinical Trials Unit at University College London said, “I’m so grateful to our STOPCAP collaborators who ran these trials and the people who took part. By exploring their valuable data further, we have taken a big step towards more personalised treatment of men with advanced prostate cancer.”
The next step for the STOPCAP M1 team is to identify which people with metastatic prostate cancer should receive second-generation anti-androgens, docetaxel or both in addition to hormone therapy.
This multi-national research project was led by the MRCCTU at UCL on behalf of the STOPCAP M1 Collaboration, funded by the UKRI Medical Research Council and Prostate Cancer UK.