Evaluating outcomes for a new radiotherapy technique in patients with breast cancer

This study looks at survival rates and side effects after 5 years following a newer radiotherapy procedure in patients with breast cancer. This radiotherapy procedure is called accelerated partial breast irradiation (ABPI) delivered using 3-dimentional conformal external beam radiation therapy (3D-CRT).

Treatment for breast cancer often starts with surgery. This surgery either removes the whole breast (mastectomy) or just the cancer (breast-conserving surgery). Radiation therapy (x-rays) can also be given after surgery, to kill off remaining cancer cells that were missed during surgery. One of the problems with radiation therapy is trying to get the beam to kill only the cancer cells. Otherwise it can cause scarring by affecting healthy tissues around the cancer. Newer radiotherapy techniques have been developed that target specifically the cancer-affected areas. ABPI is a type of radiotherapy given only to the part of breast that has the cancer in it. It uses a higher dose of x-rays over a shorter period of time. 3D-CRT is a technique where the radiation beam is shaped to match the cancer so it will not affect the healthy surrounding tissues. This study evaluated the long-term outcomes for patients treated with (3D-CRT) ABPI. 

This study followed 192 patients with breast cancer treated with breast-conserving surgery and (3D-CRT) APBI. Patients were followed up for 5 years and the main parameters evaluated were cancer recurrence (return of the cancer), disease-free survival (defined as the percentage of patients cured of the disease) and overall survival (defined as the percentage of patients who have survived for a certain period of time). Patients were also monitored for side effects and cosmesis (appearance of the scar after treatment). After 5 years from treatment, none of the patients included in the study had a recurrence. Also, disease-free survival was 98% and overall survival was 92%. 81% of patients had excellent or good cosmesis and only 4% had poor cosmesis. The most common long-term side effects reported were skin discoloration or inflammation (dermatitis), breast pain and swelling of the breast, scarring or spider veins.

In summary, (3D-CRT) APBI was very effective in preventing recurrence, with good cosmetic results in a selected group of patients with breast cancer treated with breast-conserving surgery. 

This study included a small group of patients. Also, some of the included patients received additional treatments such as chemotherapy or hormonal therapy which may have influenced their outcomes.