New study sheds light on post-radiation mammography timing. Image Source: Siemens

Breast cancer patients who receive breast-conserving therapy and radiation do not need a follow-up mammogram until 12 months after radiation, according to a study published in the Nov. 15 issue of International Journal of Radiation Oncology*Biology*Physics.

Current American Society of Clinical Oncology (ASCO) and National Comprehensive Cancer Network (NCCN) guidelines that recommend follow-up mammograms at between six and 12 months after radiation. Accounting for the time after the initial diagnostic mammogram to have a biopsy, surgery and radiation therapy, following the ASCO guidelines would likely result in mammograms being done six to nine months after the completion of radiation, according to the study authors.

Kevin Lin, MD, lead author of the study, and colleagues at the University of California, Los Angeles (UCLA), School of Medicine, and at the University of California, San Diego, School of Medicine, sought to determine if the recommended timeframe for a post-treatment mammogram offers any benefit to 408 patients who were treated with breast-conserving therapy and radiation between 1995 and 2005 and who had follow-up mammograms at UCLA within one year after completing radiation.

According to the results, the median interval between radiation and the initial mammogram was 3.1 months. Only 10 patients had suspicious findings on their mammograms and of those only two were found to have recurrent cancer. Both of the cases were noninvasive ductal carcinomas, the researchers discovered.

The cost of a mammogram is about $115 and many women can experience moderate to severe pain during the procedure and high levels of anxiety during a needle biopsy, the authors said. Based on the study findings, “since only 0.49 recurrences were detected per 100 mammograms and only noninvasive ductal carcinoma was found, mammograms should not be performed until at least one year after radiation to avoid the medical and psychological costs associated with mammography,” Lin said.

“Omitting the initial post-radiotherapy examination may improve the psychological well-being of patients, especially for women who have already been shown to have breast cancer,” he noted.