Long-Term Study Reveals Radiotherapy's Impact on Breast Cancer Recurrence

A new long-term study sheds light on the effects of radiotherapy after breast cancer surgery, revealing that it can significantly reduce the chances of cancer returning in the same location for up to 10 years. However, the protective benefits of radiotherapy seem to diminish after a decade, making the risk of recurrence similar to those who did not undergo the treatment.

The Scottish Breast Conservation Trial, conducted by researchers at the University of Edinburgh, followed 585 women in Scotland who were treated for early-stage breast cancer. Half of these women received radiotherapy after surgery, while the other half did not. The average follow-up period for these patients was 18 years, with some cases extending to over three decades.

One of the key findings of the study was that 16% of the women who received radiotherapy experienced a recurrence of breast cancer in the same location within 10 years, compared to 36% of those who didn’t receive the treatment. Despite this significant difference, overall survival rates remained similar between the two groups over 30 years, with those who had radiotherapy living an average of 19.2 years compared to 18.7 years for those who did not.

Interestingly, the study also noted that while radiotherapy led to fewer deaths from breast cancer (37% versus 46%), there was a higher incidence of deaths from other cancers in the radiotherapy group (20% versus 11%).

These findings offer a more comprehensive view of the long-term effects of radiotherapy following breast cancer surgery. As improvements in early detection and treatment allow patients to live longer, understanding the lasting impacts of these treatments becomes crucial.

Dr. Linda Williams from the University of Edinburgh’s Usher Institute, who led the study, highlighted the importance of such long-term research. She noted that following patients beyond the typical 10-year period is essential for fully assessing the benefits and risks of treatments like radiotherapy.

Supporting the continued use of radiotherapy in early-stage breast cancer treatment, Professor Ian Kunkler from the University of Edinburgh’s Institute of Genetics and Cancer emphasized that the treatment effectively reduces the risk of cancer recurrence within the first 10 years. However, he also acknowledged that, like many anti-cancer therapies, radiotherapy’s protective effects wane over time.

This study, which was published in The Lancet Oncology, involved collaboration among experts from several institutions, including the Usher Institute, the Institute of Genetics and Cancer, Public Health Scotland, Queen Elizabeth University Hospital in Glasgow, and the Western General Hospital in Edinburgh. The findings are expected to play a significant role in shaping future guidelines for breast cancer treatment.