November 17, 2022

expert reaction to an unpublished abstract on long term follow up of health outcomes and survival after radiotherapy for breast cancer

A conference abstract (not a published paper) presented at the European Breast Cancer Conference gives results from a 30-year analysis of the Scottish breast conservation trial.

Prof Stephen Duffy, Centre Lead, Centre for Prevention, Detection and Diagnosis, Wolfson Institute of Population Health, Queen Mary University of London, said:

“This is a high quality study with impressive 30-year follow-up. The results indicate a significant reduction in local recurrence with radiotherapy in patients who received breast conserving surgery. In this trial, no short or long term effect on overall survival was observed. A word of caution is necessary here. The results are somewhat at odds with the Early Breast Cancer Trialists’ meta-analysis of trials with a total of more than 10,000 patients, which found a significant but small improvement in overall survival at fifteen years, and a larger reduction in risk of death from breast cancer. Taken all in all, it is reasonable to conclude that the effect of radiotherapy on overall survival is at best modest, but the Early Breast Cancer Trialists’ results, along with the reduction in local recurrence on which all the studies are agreed, suggest that radiotherapy is still a worthwhile option in patients receiving breast conserving surgery, or at least a substantial proportion of such patients.”  

Prof Nazanin Derakhshan, Professor of Experimental Psychopathology, University of Reading said:

“While the conclusions drawn from this study are thought-provoking, they are limited. The study does show a closing of the gap between patients who had radiotherapy and those who didn’t, after 20 and 30 years. But although this doesn’t show a significant difference, quantitatively, from a patient perspective, it may still be important. The remaining difference is still enough that many would choose radiotherapy over no radiotherapy.

“The first 10 years after diagnosis is a profound milestone for early stage breast cancer patients. Many patients are thrilled to even make it to five years post active treatment. The benefit of radiotherapy with respect to survival to 10 years is clear to see from the data and should be reason enough to choose to treat.

“The overall survival up to 30 years isn’t affected by whether the patient had radiotherapy or not. While interesting, this result does not take into account the psychological health of patients. Uncertainties that fuel fear of recurrence are a scourge on the patient community. The fear that breast cancer may come back is well known to be disabling and affects a majority of breast cancer patients.”

Dr Stephen Tozer-Loft, Head of Radiotherapy Physics, Sheffield Teaching Hospitals NHS Foundation Trust, said:

“From the little I’ve seen, the science of the trial, and its execution seem good. The press release nicely summarises the findings of the work and puts them in a good context, in general.

“The work described is significant and precious because it shows the value of a commitment to very long-term follow-up of patients undergoing cancer treatment.  However the study’s strength is also it’s weakness in that it involves patients who were treated more than 30 years ago.  Since that time, an awareness of the impact of radiation on sensitive organs at risk, in particular the heart, has led to the development of much more sophisticated treatment techniques which significantly reduce the radiation doses received by the heart during radiotherapy compared with a standard breast radiotherapy technique delivered 30 years ago.  One example is Deep Inspiration Breath-Hold (DIBH) whereby patients take a deep breath which is held during the radiation delivery, which moves the heart away from tissues which need to receive the highest radiation doses. I would worry that Professor Kunkler’s sentence which includes the phrase “radiotherapy…may also cause a few more deaths…” might cause concern to patients considering their options, and should be moderated by pointing out the improvement in accuracy and safety of the radiation techniques that are currently in use.  So one would expect that the particular statistical outcomes of patients undergoing treatment now or in the future would be quite different (better) than those pertaining to patients who were treated 30 years ago.”

The abstract ‘Randomised controlled trial of breast conserving therapy: 30-year analysis of the Scottish breast conservation trial’ by L. Williams et al. was presented at the European Breast Cancer Conference on Thursday 17 November.

Declared interests

Prof Nazanin Derakhshan: “No declarations of interest.”

Dr Stephen Tozer-Loft: “I work as a Radiotherapy Physicist in the NHS, so have a professional interest in radiotherapy, but can declare that I have no conflicting interests that would affect my views.”

For all other experts, no reply to our request for DOIs was received.