Breast Cancer Brachytherapy May Be Overused
Many women who were not ideal candidates for accelerated partial breast irradiation based on treatment guidelines regularly receive the treatment, according to a population-based study.
Between 2000 and 2007, 2.6% of nearly 140,000 U.S. women with nonmetastatic breast cancer underwent accelerated partial breast irradiation (APBI) using brachytherapy (APBIb) and 65.8% of them were classified as “cautionary” or “unsuitable” for the procedure per ASTRO guidelines, reported Jona Hattangadi, MD, from Brigham and Women’s Hospital in Boston, and colleagues in the Journal of the National Cancer Institute.
In general, APBI offers advantages over whole-breast irradiation (WBI), including decreased treatment times and reduced radiation dose. But the therapy does carry a higher risk for tumor recurrence.
Because of a lack of evidence establishing the long-term efficacy and safety of APBIb, ASTRO issued consensus guidelines in 2009, rating therapeutic appropriateness based on patient characteristics and clinical factors.
Hattangadi and colleagues evaluated data from the Surveillance, Epidemiology, and End Results (SEER) database. They identified 138,815 women who underwent WBI or APBIb after breast conserving surgery for stage 0 to III disease. Their goal was to evaluate patterns of use with respect to the ASTRO guidelines.
According to the results, APBIb was used in 5% of patients who met the ASTRO guidelines for “suitable.” The treatment was used in 3.4% for whom it was deemed “cautionary.” Finally, 1.6% of patients who met the criteria for “unsuitable” for APBIb had the procedure (P<0.001).
Brachytherapy: Targeted Radiation Therapy for Breast Cancer
Along with surgery and chemotherapy, radiation is the other leg of the conventional breast cancer treatment triangle. The primary use for radiation is as a supplement to a lumpectomy, which involves the surgical removal of a breast cancer tumor plus some immediate surrounding tissue. This combination of lumpectomy and radiation has helped a lot of women avoid the necessity of a full mastectomy, allowing their cancers to be treated aggressively and effectively without removal of the entire breast.
When most people think of radiation treatment for breast cancer, what they picture is a procedure known as external beam radiation. This technique uses focused doses of radiation beamed at the body to target tumors on the inside of the breast. Understandably, given the legacy of Hiroshima, Nagasaki, Chernobyl, and now Fukushima, most women facing the possibility of having bursts of radiation beamed at their bodies become quite nervous and fearful. While the technology is controlled to ensure that only cancer cells will receive killer doses, just hearing the word ‘radiation’ is bound to bring chills to anyone.
But despite what most people believe, external beam radiation is not the only alternative for women who need radiation following a lumpectomy. For some women, another type of radiation treatment called brachytherapy is a legitimate option.
What is Brachytherapy?
The procedure called brachytherapy uses a series of tiny tubes or catheters that are inserted into the body to deliver tiny sources of radiation directly to the site of malignant tumors. While normal radiation treatments send radiation into the body to hopefully kill cancer cells while not doing any other damage on their way in, brachytherapy allows the radiation to be delivered directly and exclusively to the spot where it is needed. While the technology of external beam radiation has improved considerably over the years, and presents much less of a danger to the human body than it used to, it is still inevitable that the cells of the lungs and the rest of the breast will be damaged to some extent by this procedure. An external beam simply cannot be focused narrowly and exactly enough to avoid this collateral damage but with brachytherapy, it is possible to target the cancerous tumor much more precisely, with the radiation essentially being injected directly into breast cancer cells.