Does a less invasive radiotherapy technique after lumpectomy prevent a breast cancer recurrence?

This study examines the efficacy of a type of radiotherapy called accelerated partial breast irradiation (APBI) as an adjuvant (additional) treatment for breast cancer patients who underwent lumpectomy.

Patients with early-stage breast cancer are usually treated with breast conserving surgery or lumpectomy (surgery that removes only the cancerous lump, leaving the rest of the breast in place). Following lumpectomy, many patients experience a recurrence (return of the cancer) in the border of the area that was operated on. Therefore, adjuvant (additional to surgery) treatments such as whole breast irradiation (WBI) can be delivered to kill the remaining cancer cells in the breast that may have been missed during surgery, thus decreasing the risk of recurrence. A newer radiotherapy technique called accelerated partial breast irradiation (APBI) has been studied instead of WBI as adjuvant treatment for these patients. APBI is involves a less invasive, more focused treatment, which gives a higher dose of radiation over a shorter period of time. APBI may be given using an external or an internal (brachytherapy) radiation beam. The authors of this study aimed to evaluate the risk for recurrence after APBI following lumpectomy in breast cancer patients.

This included 322 women with breast cancer treated with lumpectomy. All patients received adjuvant APBI by brachytherapy. After approximately 5 years of follow up, 94.4% of participants did not experience any recurrences of the cancer. The 5-year overall survival (the percentage of patients surviving 5 years after the treatment) was 92.8% and the disease-free survival (defined as the percentage of patients without any sign of the disease 5 years after the treatment) was 92.4%. Analysis showed that patients whose cancer did not grow in response to estrogen, the main female sex hormone (estrogen receptor-negative or ER-), were more likely to have a recurrence compared to those with estrogen receptor-positive (ER+) breast cancer. Other factors associated with a higher risk of recurrence were the presence of extensive intraductal component or EIC (25% or more of the cancer invades the milk ducts of the breast) and invasion of the lymph vessels. 

Overall, this study shows that APBI after a lumpectomy may be a useful and successful treatment for breast cancer in a specific group of patients. The authors of this study found several pathological features that may indicate which patients can benefit the most from this treatment. 

Further studies need to be carried out to ascertain if APBI results in a higher risk of recurrence of the cancer in breast cancer patients compared to conventional treatments.

Discuss with your doctor whether APBI is a good treatment option for your situation.