Giving patients chemotherapy drugs more regularly reduces the risk of cancer returning and even death, according to new research.
The study by the Early Breast Cancer Trialists’ Collaborative Group (EBCTCG), which included researchers from the MRC Population Health Research Unit at the University of Oxford.
Over 37,000 women with early (operable) breast cancer took part in 26 trials from across the world that compared dose-intensity and standard schedule chemotherapy.
The investigation aimed to discover if increasing the dose intensity of chemotherapy would be more effective at lowering breast cancer regrowth and death rates, when compared to standard schedule chemotherapy regimens.
One method used saw drugs were administered every 2 weeks instead of the usual 3-week schedule, causing the average weekly dose to be 50% higher.
Another way of increasing the dose intensity of chemotherapy was to give the drugs individually in sequence rather than administering all the drugs together at the same time. This meant higher doses of the drugs were in each cycle, this kept the side effects manageable.
“The risk of dying of breast cancer can be reduced by at least 40%”
Study co-author Richard Gray, Professor of Medical Statistics in the Nuffield Department of Population Health at the University of Oxford, was pleased with the results.
He said: “We were surprised by how strong and consistent the findings from our study were. Patients who received chemotherapy every two weeks were 17% less likely to have disease recurrence and 15% less likely to die from breast cancer within 10 years, compared with those who received treatment every three weeks.
“Similar results were seen for patients who received sequential chemotherapy rather than concurrent treatment and, overall, analysing all the patients together there was a 14% proportional reduction in the risk of breast cancer recurrence. The reduction in the 10-year risk of breast cancer recurrence was 4.3%.”
“The results show definite benefit from the more intense treatments”
The number of breast cancer deaths over the last 30 years has halved due to continuous improvements in the development of medicine and treatment.
Professor Gray continued: “Though the benefits of dose-intense over standard chemotherapy are only moderate, this new research does show that by using dose-intense chemotherapy, the risk of dying of breast cancer can be reduced by at least 40% compared to no chemotherapy.”
Study co-author, Dr Jeremy Braybrooke explained that some treatment centres prefer to give patients the cancer-fighting drugs every two weeks due to concerns about side-effects.
He explained: “Looking at the data from large numbers of women receiving dose-intense chemotherapy, we have found no evidence to justify these concerns, and the results show definite benefit from the more intense treatments, including the fact that treatment can be completed sooner.
“Although dose-intense chemotherapy is clearly more effective at eradicating cancers, more research is still needed as it is difficult to recommend any one particular dose-intense chemotherapy regimen based on this study.”