The humble grape could tackle a painful side effect of breast cancer radiotherapy for which there is currently no effective treatment.
A clinical trial funded by Cancer Research UK and conducted by The Royal Marsden Hospital and The Institute of Cancer Research, is to investigate the healing properties of grape seed on a potentially distressing side effect of high dose radiotherapy called radiation fibrosis.
Thousands of breast cancer patients worldwide are affected by the condition in the years after radiotherapy. The changes result in breast tissue becoming harder and sometimes tender. This can cause patients inconvenience, and in some women the changes are severe and have a major impact on day-to-day life.
The latest radiotherapy techniques are safer and more effective against cancer, but the possibility of permanent side-effects cannot be eliminated.
Radiation fibrosis is a type of scarring that causes tissue to become hard and stiff. In addition, it is thought that a build up of fluid escaping from tiny blood vessels into the spaces between cells adds to hardness.
Royal Marsden consultant Professor John Yarnold is the principal investigator for the trial and is based at The Institute of Cancer Research. He says: “Radiotherapy is followed over the years by tissue hardening and tenderness in the breast and underlying muscles in some women. We aim to test if grape seed extract reverses these changes and improves patients’ quality of life.”
“If successful, we aim to conduct further clinical trials in radiotherapy patients cured of other cancers where fibrosis may cause other serious medical problems.”
Prof Yarnold points out that it is not clear how fibrosis develops, but the most likely mechanism involves the continuous release of free radicals, triggered by radiotherapy.
These highly aggressive molecules are generated by many cell reactions in response to stress. They spread a kind of biological rust and can cause havoc in cells – damaging anything in their path, including DNA.
If free radicals are involved in breast tissue hardening, antioxidants could put a halt to this cellular blight by mopping up these molecules.
Prof Yarnold says: “Grape seeds contain a mixture of compounds called flavanoids, also found in other fruits and vegetables. They have antioxidant properties that may be superior to known antioxidants like vitamin E or C. There have already been promising small scale trials with antioxidants, but I believe grape seed extract has interesting potential.”
He adds that the trial will also involve taking tissue biopsies so that researchers can understand the molecular mechanisms of any process observed.
Sir Paul Nurse, Chief Executive of Cancer Research UK, says: “We hope this trial will eventually lead to a treatment for patients who previously had no respite from the symptoms of radiation fibrosis.”
The trial will initially recruit 72 patients. The research volunteers will be asked to have magnetic resonance imaging scans at Mount Vernon Hospital or The Royal Marsden Hospital. They are also asked to provide blood, urine and breast tissue samples, so that researchers (including collaborator Professor D Bagchi of the Creighton University School of Pharmacy, Nebraska, USA) can learn more about the molecular mechanisms of any process observed.
The treatment (which will be given under medical supervision) or placebo (dummy tablets) is allocated at random and given over six months, after which patients are followed up for 6-months. During this time, neither they nor the researchers know whether they are taking tablets containing grape seed extract or placebo. The tablets used are not available over the counter or on regular prescription.
Further trials information for patients is available on CancerHelp UK. Patients interested in the trial should contact their doctor.
Breast cancer is the most common cancer in UK women. More than 39,500 new breast cancer cases were diagnosed in 1998.
Treatment for breast cancer usually comprises surgery followed by radiotherapy or chemotherapy.
The Institute of Cancer Research is a centre of excellence with some of the world’s leading scientists working on cutting edge research. It was founded in 1909 to carry out research into the causes of cancer and to develop new strategies for its prevention, diagnosis, treatment and care.
The Royal Marsden is the UK’s leading comprehensive cancer centre and is recognised world-wide for the quality of its services. Thirty thousand patients attend its hospitals at Chelsea and Sutton each year.