Highly Targeted Irradiation Works as Well as Whole Breast Radiotherapy in Early Stage Breast Cancer

Csaba Polgar, MD, director of the Centre for Radiotherapy, National Institute of Oncology (Budapest, Hungary) told the World Congress of Brachytherapy, which was held in in Barcelona (Spain) during May 9-13, 2012, that he believes accelerated partial breast irradiation (APBI) could be offered to many more breast cancer patients, resulting in fewer side effects and major cost savings to healthcare systems.

The Budapest trial was the first randomized study to compare the efficacy and side effects of conventional whole breast irradiation with APBI using multicatheter brachytherapy. This technique consists of inserting multiple plastic catheters into the tumor bed after breast conserving surgery. The catheters are inserted under local or general anesthesia, according to the wishes of the patient. The radiation source is then loaded into them to deliver a highly concentrated dose to the exact region of the excised tumor--the region most likely to develop a local recurrence of the cancer. By using APBI, the major part of the healthy breast tissue does not receive radiation.

“In a group of 258 women who had had breast-conserving surgery, we found that, at a median follow-up time of just over 10 years, the rate of local recurrence--the cancer coming back in the same place--was 5.9% in the APBI group and 5.1% in the group who received whole breast irradiation,” said Prof. Polgár. “There was no significant difference in overall survival, cancer-specific survival, and disease free survival between the two groups. However, the differences in cosmetic outcome were striking--81% in the APBI group had good-to-excellent results as opposed to 63% of those who received whole breast irradiation.”

An additional benefit of APBI is that treatment time can be shortened. As opposed to whole breast irradiation, where a course of treatment typically takes five weeks (five treatments per week), APBI can be performed in four to five days. “We believe that the results of our trial will encourage more patients to choose APBI, particularly those who may now be inclined to refuse radiotherapy because of the logistical difficulties involved--having to travel long distances over a period of six weeks can be a major problem for some patients,” Prof. Polgár noted.

Fewer than 10% of early stage breast-cancer patients currently receive APBI in Europe, and in some countries, it is still considered an investigational treatment. In other parts of the world, for example, in the United States, it has already been accepted into general practice for the treatment of selected low-risk patients.

“Our trial has shown that it is possible to use a faster and more focused treatment without compromising survival. It is a little like comparing a total mastectomy with a lumpectomy--we have found that we can improve cosmetic outcomes, lessen side effects, and achieve greater patient satisfaction with a less invasive and more cost-effective technique. Other multicenter trials of APBI are currently underway, and we believe that these are likely to give further support to our findings,” Prof. Polgár concluded.

Dr. Christine Haie-Meder, a radiation oncologist at the Institut Gustave Roussy (Villejuif, France) and chairperson of the congress, said, “We know that all the patients with breast cancer do not need whole breast irradiation. Especially in elderly patients, the treatment, when limited to partial breast irradiation, can be significantly shortened. This study is important because, within the frame of a randomized trial with a 10-year follow-up, it shows that in selected patients, partial breast irradiation gives as good results as whole breast irradiation with the same recurrence rate, but with significantly better cosmetic results.”

Brachytherapy is a type of internal radiotherapy, which involves putting solid radioactive material close to, or inside, the tumor. This gives a high dose of radiotherapy directly to the tumor but only a low dose to normal tissues.

The World Congress of Brachytherapy was held in parallel with the 31st conference of the European Society for Radiotherapy and Oncology (ESTRO 31).

Related Links:
Hungarian National Institute of Oncology