A new study into treatment for prostate cancer has some promising news for men affected by this condition. The findings have shown that changing the way one treatment is given doesn’t affect survival, and helps patients by reducing side effects.
The UK section of this international trial was funded by Cancer Research UK and led by The Institute of Cancer Research, London. This phase 3 trial involved almost 1,400 men who had already received radiotherapy treatment, which had failed to clear their cancer.
The patients were divided into two groups. One group received an existing hormone therapy drug continuously, which is the standard current treatment. The other group was given the same hormone therapy drug, but treatment was stopped after eight months. This group’s doctors checked their prostate specific antigen (PSA) levels every two months. (PSA is a protein. If you have high levels of PSA it can mean that you have cancer if you haven’t already been diagnosed. In this case the PSA test indicated whether the hormone treatment needed to be re-started.) The men in the study were followed up for an average of around seven years.
When a patient’s PSA level reached a certain level (10 ng per millilitre), their hormone treatment began again, for another eight months. This cycle of eight-monthly treatment interspersed with breaks continued until the end of the treatment.
The results from this trial showed that taking hormone therapy intermittently, rather than continuously, didn’t make a difference to the patients’ length of survival. However, the study did show potential benefits when it came to side effects. The group that received intermittent treatment reported fewer urinary problems and hot flushes, improved sex drive and ability to have an erection.
UK chief investigator Professor David Dearnaley, professor of uro-oncology at The Institute of Cancer Research and honorary consultant at The Royal Marsden NHS Foundation Trust, said: “This large-scale trial has shown that periodically stopping men’s hormone therapy can give them fewer side-effects without reducing their clinical survival, and should lead to a change in clinical practice.
“More than 10,000 men are treated with potentially curative radiotherapy for prostate cancer each year in the UK and so our findings have the potential to benefit thousands of men.
"It would be possible for specialist oncologists and urologists to implement this treatment strategy straight away for individual patients. Many oncologists, in fact, will have been using this approach already.
“The monitoring of the intermittent or ‘stop-start’ approach is a little more complicated than the more standard method of continuous hormone therapy with androgen suppression which, in many instances, will be monitored by general practitioners. Monitoring using continuous hormone therapy is quite simple and based on PSA levels (which should be low) and clinical symptoms. Referral back to a specialist is only required if the PSA level rises.
“In practice, the ‘stop-start’ approach may be more difficult for many General Practitioners to manage. This has the implication that more patients would need to be followed by specialist oncologists and urologists which would alter the patterns of care and 'patient pathways' in many areas.” Professor Dearnaly pointed out that any savings from the reduced use of hormone therapy (which costs approximately £100/month) would need to be balanced against the increased cost of more frequent specialist monitoring when using the intermittent ‘stop-start’ approach.
“It is very important to manage men with prostate cancer recurrence of this type on an individual basis,” added Professor Dearnaly. “For those who have significantly troublesome symptoms from hormonal therapy, the intermittent approach will be very attractive. Many men, however, have very little in the way of side effects from androgen suppression (hormone therapy), and for these individuals intermittent therapy may offer very little advantage and such men may prefer the easier monitoring with a continuous treatment approach.”
“Results such as these highlight the value of clinical trials,” says Kate Law, Cancer Research UK’s director of clinical research. “Refining treatment to reduce side-effects and improve the outcome for patients remains the key goal. And being able to reduce the side-effects of prostate cancer treatments from currently available treatments offers patients and their doctors the potential of a new option of how their treatment is delivered.”
Cancer Research UK - www.cancerresearchuk.org
NHS Choices - www.nhs.uk
Prostate Cancer UK - http://prostatecanceruk.org