Single breast cancer dose as good as full course
A single dose of radiotherapy during surgery is as good as a conventional course for most women with early breast cancer, a study has found.
Researchers said the single dose of targeted radiotherapy during surgery replaced the need for extra hospital visits as part of a regular course.
An international team of researchers compared the long-term effects of targeted intra-operative radiotherapy (TARGIT-IORT) with conventional whole breast external beam radiotherapy (EBRT) for women with early breast cancer.
TARGIT-IORT is the combination of targeted radiotherapy restricted to the area around the tumour given immediately after surgery.
Conventional radiotherapy involves repeat doses to the whole breast over several days after surgery.
The findings, published in the British Medical Journal, showed that intra-operative radiotherapy was associated with around an 80 per cent chance of avoiding a full course, fewer side effects and no difference in survival or likelihood of the cancer returning.
A total of 2,298 women aged 45 or older who were eligible for breast conservation surgery, known as a lumpectomy, were randomly split so 1,140 received TARGIT-IORT and 1,158 had EBRT between March 2000 and June 2012.
TARGIT-IORT was given as a single dose immediately after surgery as part of the same operation and under the same anaesthetic, while EBRT was given as a standard daily dose for three to six weeks after surgery. Researchers said the long term results showed TARGIT-IORT was no worse than EBRT.
After five years of monitoring, the local recurrence risk was 2.11 per cent for TARGITIORT compared with 0.95 per cent for EBRT, but the difference of 1.16 per cent was not considered clinically significant, they added.
The team also found that in the five years after surgery, there were 13 additional local recurrencesfortargit-iort compared with EBRT – 24 out of 1,140 compared with 11 out of 1,158. But the researchers said there were 14 fewer deaths with TARGIT-IORT compared with EBRT – 42 out of 1,140 compared with 56 out of 1,158.
Researchers said that over a longer follow-up period, averaging 8.6 years, there were no statistically significant differences in local recurrence-free survival, mastectomy-free survival, overall survival and breast cancer deaths.
They said the study’s randomised design, a large sample size, a long duration and high level of complete followup suggested the results were “reliable and robust”.
But the team said there were limitations affecting the results, such as the possible over-diagnosis of non-invasive local recurrence, and not collecting all the background risk factors for deaths from non-breast cancer causes.
Researchers said that for a large proportion of early breast cancer patients, “riskadapted immediate singledose TARGIT-IORT during lumpectomy is an effective alternative to EBRT, with comparable long-term efficacy for cancer control, and lower nonbreast-cancer mortality”.
They added that single-dose Targit-iortduringlumpectomy “should be accessible to healthcare providers and discussed with patients”.