The Cancer Research Campaign has appealed to all breast cancer experts in the United Kingdom to take part in a huge trial of the drug tamoxifen, writes Aisling Irwin.
The trial, which aims to reach 20,000 women, will be the world's largest cancer treatment trial, the CRC claims. Such numbers render a trial very statistically powerful and have been used in cardiovascular trials.
Tamoxifen is a relatively new drug given to women who have had surgery for breast cancer. It delays recurrence of the disease and prolongs survival. But at present it is only given for two years. Scientists want to know whether giving the drug for five years enables women to survive even longer. If there was improved remission this would have to be balanced against any side-effects from five years on the drug, which may cause endometrial and liver cancers.
The trial depends crucially on finding enough cancer experts to take part, said David Kerr, clinical director of the CRC Institute for Cancer Studies at Birmingham University.
"If anybody can pull it off we can," he said. "But we do feel there's a question mark about it." As a carrot, the CRC has said that any collaborator will be included as an author on the resulting papers, a privilege normally reserved for the organisers of a study, who include Helena Earl of the Birmingham Institute, and Martin Lee, of Dudley Road Hospital, Birmingham.
Collaborators are also being told that all they have to do after registering the women is to tick a box once a year, to say whether or not the women are still alive.
The trial differs from a controversial tamoxifen trial which began several years ago, run by the two major cancer charities. In this, women with no breast cancer but a family history of the disease are given the drug as a preventative measure. Ann Oakley, sociologist at the Institute of Education, who criticised the earlier trial, said that the new trial did not raise such issues. But she said that women should be properly informed about the risks of the drug.
Professor Kerr said: "We're being very honest, saying that we don't know how long women should be treated for. We need this information. We have reached a fork in the road in terms of developing tamoxifen. But we mustn't overplay the problems of endometrial cancer. We don't feel there's an awful ethical dilemma here."