How Breast MRIs Are Being Used

Breast MRI usage skyrocketed then stabilized during last decade

(RxWiki News) Actress Christina Applegate, the daughter of a breast cancer survivor, had her first breast MRI (magnetic resonance imaging) in 2007. The next year she was diagnosed with breast cancer. Are more women following in Applegate’s footsteps?

Between 2000 and 2009, the use of breast MRI skyrocketed, increasing more than 20-fold, before declining slightly and stabilizing, according to a newly published study.

Researchers found that breast MRI was used mostly for screening and monitoring for a breast cancer recurrence (return) among women with a personal or family history of breast cancer.

"Establish a breast cancer screening routine with your doctor."

Natasha K. Stout, PhD, of Harvard Medical School and the Harvard Pilgrim Health Care Institute in Boston, and colleagues examined 10,518 women over the age of 20 from two multistate New England health plans who had undergone at least one breast MRI between 2000 and 2011.

MRI studies use a magnetic field, radio waves and a computer to create detailed images of the breast.

According to the American Cancer Society and the Comprehensive Cancer Network, breast MRI is recommended for women with a lifetime breast cancer risk of more than 20 percent.

While MRIs are known to be more sensitive than mammograms in detecting breast cancer, no studies have been conducted to determine how many lives have been saved by using MRI as a screening tool.

Breast MRIs were used in the study for four indications:

  • To screen for breast cancer
  • To perform a diagnostic evaluation for breast symptoms or to evaluate a suspicious finding discovered on an earlier imaging study
  • To stage (establish extent of disease) diagnosed breast cancer or monitor progress of treatment
  • To monitor for a breast cancer recurrence

In an accompanying editorial, E. Shelley Hwang, MD, MPH, of the Duke Cancer Institute, and Isabelle Bedrosian, MD, of The University of Texas MD Anderson Cancer Center, pointed out that "...breast MRI continues to be used outside the screening context in areas such as staging of new breast cancers and post-treatment surveillance where there exist insufficient data to support its use.”

Analyzing patient records from the New England plans, Dr. Stout and colleagues found the following:

  • Breast MRI use increased more than 20-fold, from six to 131 per 10,000 women, between 2000 and 2009 and then declined slightly to 105 per 10,000 by 2011.
  • Over the entire study period, MRI use increased 16-fold.
  • From 2003 to 2009, use increased 46 percent a year, then decreased annually by 10 percent between 2009 and 2011.
  • The highest use of breast MRI was seen among women aged 40 to 59.
  • Women were an average age of 49 when they had their first breast MRI.
  • 51.7 percent of the women who had breast MRIs had a family history of breast cancer, while 3.5 percent had a known BRCA mutation, which increases a woman’s lifetime risk of breast cancer.
  • The greatest increases were seen in MRIs for breast cancer screening and surveillance, with these two indications accounting for 57.6 percent of MRI use by 2011.

The authors of this study wrote that more research should be conducted to learn who is receiving breast MRIs to maximize health resources.

"We do not know if using MRI to look for additional foci [tiny spots] of cancer among women recently diagnosed with breast cancer is good, or not so good," said Daniel B. Kopans, MD, professor of radiology at Harvard Medical School and senior radiologist of the Breast Imaging Division at Massachusetts General Hospital. "Prior to the use of MRI, modern therapy had reduced the recurrence rates in the breast at 10 years to less than 5 percent."

Dr. Kopans told dailyRx News, "Using MRI detects foci of cancer that had been undetected in the past, and this often leads to more mastectomies. We do not know if these additional lesions were, in the past, being eliminated by therapy avoiding mastectomy. A randomized, controlled trial is also needed to evaluate this unanswered question," said Dr. Kopans, who was not involved in this study.

In their commentary, Drs. Hwang and Bedrosian concluded, “As a medical community, we bear a collective responsibility to ensure that breast MRI provides sufficient clinical benefit to warrant the additional biopsies, increased patient anxiety, and cost that accrue with its use.”

Christina Applegate later credited MRI for saving her life.

Findings from this study and the editorial were published November 18 in JAMA Internal Medicine.

The American Cancer Society and the National Institutes of Health funded this research.

No conflicts of interest were disclosed.

Review Date: 
November 18, 2013