The latest study on breast cancer appears to question the efficiency of an MRI or magnetic resonance imaging given to more newly diagnosed breast cancer patients before surgery.

To be more specific, the study strongly supports that getting an MRI appears to delay the start of treatment by three weeks, which may not affect a woman’s survival, but certainly adds to her anxiety. Also, the study showed that women having MRIs are more likely to get mastectomies, instead of breast-conserving lumpectomies, mostly because MRIs can pick up suspicious spots outside the original lump.

For the study, Dr. Richard Bleicher, a breast cancer surgeon at Fox Chase Cancer Center in Philadelphia and colleagues analyzed 577 breast cancer patients who had been evaluated by a radiologist, pathologist and a surgical, radiation and medical oncologist. The findings were presented Saturday at a meeting of the American Society of Clinical Oncology in Washington D.C.

The study found that 130 of the patients had MRIs before surgery to remove their tumors and 27.7 percent of these had a mastectomy. Of those not having MRIs, 19.5 percent had a mastectomy. These figures clearly state that having an MRI almost doubled the chances that a woman would undergo a mastectomy. One possible explanation for this finding was that the MRI, being highly sensitive, might have picked up something that looked like cancer but turned out not to be – a false positive.

The findings add to research presented earlier this year by Mayo Clinic researchers who found that the mastectomy rate has increased to levels close to those not seen since 1997.

“MRI may not be as good as we think it is. Those who received an MRI had a three-week delay in the start of their treatment. In addition to the treatment delay, we’re concerned that the well-documented false-positive rate with MRIs may be leading – or misleading – women into choosing mastectomies,” Dr. Bleicher said.

He further added that “MRIs are valuable and should be done in certain women at high risk, but they are not appropriate in routine evaluation of breast cancer.”

However, more research needs to be done in order “to come up with a general recommendation. It’s not a cut-and-fried issue,” Debbie Saslow, director of breast and gynecologic cancer at the American Cancer Society, said.

According to the American Cancer Society, breast cancer is the top cause of cancer death among women worldwide with an estimated 500,000 death annually. In the US each year, more than 180,000 new breast cancer cases are diagnosed and more than 40,000 women die because of it.

The study was supported by a U.S. Public Health Service grant and by an appropriation from the Commonwealth of Pennsylvania.