Therapy trial offers breast cancer patients hope
Women with an early form of breast cancer are more likely to stay free of the disease after an extra radiotherapy boost, new research shows.
In the first trial of its kind, experts followed 1,608 women with higher risk ductal carcinoma in situ (DCIS) from 136 participating centres in 11 countries.
The results showed that following surgery 803 women who received an additional boost of radiotherapy where the tumour was removed had a reduced chance of the cancer coming back to the same place.
The women who received the extra treatment stayed cancer-free five years afterwards (97.1 per cent compared to 92.7 per cent with no boost), but were more likely to experience side effects including breast pain and skin hardening.
Around 7,000 people in the UK are diagnosed with DCIS every year.
DCIS occurs when cancer cells develop in the ducts of the breast and do not spread into the surrounding breast tissue or other parts of the body.
However, if left untreated, an estimated half of DCIS cases will develop into invasive breast cancer.
When DCIS is limited to a small area, clinicians usually recommend breast-conserving surgery, removing only the small area of the breast affected. This may be followed by a course of radiotherapy to the whole breast if there is a higher chance DCIS might return.
The research, which is published in The Lancet, was coordinated by the Breast International Group and included UK teams based at the University of Edinburgh, Western General Hospital in Edinburgh, the University of Sheffield, Weston Park Hospital in Sheffield and the Royal Surrey County Hospital.
Part-funder of the research, Breast Cancer Now, has awarded the team at the University of Edinburgh a new grant of £79,000 so they can continue to monitor the UK participants in the trial.
They will track the rate of cancer recurrence and the side effects in the women who had had the additional radiotherapy boost.
Boost radiation is regularly used to treat women with invasive breast cancer, but this is the first time we have been able to demonstrate that it is an effective treatment for women with higher risk DCIS. We are hugely encouraged by these results and the Breast Cancer Now grant will help us to understand the longer-term impact of the additional radiotherapy so that in the future, patients and clinicians can make an informed decision about whether it is right for them.
It is vital we develop smarter, more effective treatments for people with breast cancer so it is incredibly encouraging that research we helped to fund has shown thousands of women with higher risk DCIS could benefit from an extra dose of radiotherapy. Breast Cancer Now’s additional funding for this work will mean we can understand the role the radiotherapy boost can play in helping to reduce the risk of cancer returning over a longer period. It will also help establish which women will really benefit from the extra treatment so that those who will not, do not unnecessarily undergo additional radiotherapy which could impact their quality of life.
"Radiation doses and fractionation schedules in non-low-risk ductal carcinoma in situ in the breast (BIG 3-07/TROG 07.01): a randomised, factorial, multicentre, open-label, phase 3 study." Chua BH, Link EK, Kunkler IH, Whelan TJ, Westenberg AH, Gruber G, Bryant G, Ahern V, Purohit K, Graham PH, Akra M, McArdle O, O'Brien P, Harvey JA, Kirkove C, Maduro JH, Campbell ID, Delaney GP, Martin JD, Vu TTT, Muanza TM, Neal A, Olivotto IA; BIG 3–07/TROG 07.01 trial investigators. Lancet. 2022; 400(10350):431-440. doi: 10.1016/S0140-6736(22)01246-6.
Press release from the University of Edinburgh: https://www.ed.ac.uk/news/2022/therapy-trial-offers-breast-cancer-patients-hope
Press release from Breast Cancer Now: https://breastcancernow.org/about-us/media/press-releases/extra-radiotherapy-boost-helps-prevent-early-form-breast-cancer-returning
Professor Ian Kunkler group website: https://www.ed.ac.uk/cancer-centre/research/kunkler-group