Nearly two thirds of U.S. women age 70 or older with stage I breast cancer1 who undergo lumpectomy and are eligible to safely omit subsequent radiation therapy (RT) according to national cancer guidelines still receive this treatment, according to new study results. The researchers looked at more than 205,000 cases of breast cancer nationwide, and their study is published as an “article in press” on the Journal of the American College of Surgeons website in advance of print publication.
After a lumpectomy, also called a breast-sparing or breast-conserving operation, radiation usually is given to the breast to reduce the chance of the cancer returning. However, treatment recommendations changed in 2004 for a select group of elderly breast cancer patients after research found that postoperative RT did not significantly prolong their survival over five years compared with women who received no RT.2
In the new study, the researchers compared post-lumpectomy RT utilization before and after 2004 and found that RT use decreased only 3 percent among women for whom the value of this treatment is questionable.
This finding demonstrates a lack of compliance with or poor awareness of the recommended treatment for what probably is a large number of breast cancer patients, said lead author Quyen D. Chu, MD, MBA, FACS, professor of surgery at Louisiana State University (LSU) Health Sciences Center, Shreveport.
“Why are we as a nation mostly not following a national guideline on breast cancer treatment?” Dr. Chu asked. “This guideline applies to a significant proportion of patients. About 30 percent of new diagnoses of invasive breast cancer3 are in women 70 and older.”
In 2004 researchers of a multicenter clinical trial, known as the Cancer and Leukemia Group B (CALGB) 9343 trial,2 advised that it is reasonable to omit RT in women with certain characteristics that put them at low risk of dying of cancer. Those characteristics were as follows:
- age 70 or older
- stage I breast cancer measuring 2 cm or less (roughly three-fourths of an inch or smaller) that has not spread to the lymph nodes on clinical examination
- estrogen-receptor-positive tumor status (the most common type of breast cancer)
- surgical removal of the tumor with lumpectomy and negative surgical margins, meaning no more cancer is observed at the edge of the removed tumor
- subsequent long-term anti-hormone therapy such as tamoxifen
They based this recommendation on their study finding that no difference existed in the length of overall survival of these elderly lumpectomy patients between those treated with and without postoperative RT plus tamoxifen.