Systematic review confirms benefit of docetaxel for men with prostate cancer
28 Sep 2015
The results of a systematic review and meta-analyses, presented on 27 September at the European Cancer Congress in Vienna, show that docetaxel improves outcomes for men with prostate cancer. These results support the findings from STAMPEDE, which were also presented at the conference.
The researchers searched for all trials looking at whether the chemotherapy drug docetaxel, added to hormone therapy, helps men with prostate cancer. They then brought together the results from all the available trials in a meta-analysis.
They found that, in men whose disease had already spread to distant parts of their body, docetaxel increased the proportion of men alive at four years from 40% to 50%. It also increased the proportion of men whose cancer had not come back or got worse, from 20% to 35% after four years.
For men whose disease had not yet spread to distant parts of their body, docetaxel increased the proportion whose cancer had not come back or got worse, from 70% to 77% after four years. However, there was no clear evidence that it helped men to live for longer. Further evidence will emerge as more trial results are published, and patients in trials like STAMPEDE are followed up for longer.
These results are very similar to those of the STAMPEDE trial (which were included in the meta-analysis). STAMPEDE found that docetaxel increased the proportion of men alive at five years by 11% among men whose disease had spread to distant parts of their body. For men whose disease had not yet spread to distant parts of the body, STAMPEDE has not yet found a clear improvement in how long men live, but has seen a reduction in the risk of the disease getting worse. Men in the STAMPEDE trial are still being followed up, which may help us answer whether docetaxel helps men whose disease had not yet spread live for longer.
The meta-analysis results are based on more than 99% of all men whose disease has spread to other parts of their body who have entered docetaxel trials. The clear results provide strong evidence to support using a combination of docetaxel and hormone therapy for men whose prostate cancer has spread to other parts of their body.
The researchers also looked into whether a type of drug used to treat bone cancers, called bisphosphonates, could help men with prostate cancer. Among men whose disease had spread to distant parts of their body, having bisphosphonates seemed to improve survival by around 5% at four years, although this result was largely down to one trial. When the researchers looked at the trials that had all used the bisphosphonate drug, zoledronic acid, there was no evidence that it helped men to live for longer. For men whose disease had not yet spread to distant parts of their body, adding a bisphosphonate drug to their treatment did not increase how long they lived.
The results of the meta-analysis looking at zoledronic acid also support the STAMPEDE results, which found no benefit of that drug for how long men lived, or reducing the risk of the disease getting worse.
