Doctors are doing more magnetic resonance images, or MRIs, of the breast to look for cancer, and as expected are finding more suspicious areas that require follow-up.

But is having the additional screening tool for breast cancer, the most common cancer in women except for skin cancer, saving lives?

"That is the question nobody knows the answer to," said Dr. Melanie Fidler, a radiation oncologist at the Women's' Imaging Center at Henrico Doctors' Hospital (Parham). "There are no studies to date to prove that breast MRI saves lives. Those will be long-term studies."

When the American Cancer Society last year released new guidelines for when to use magnetic resonance imaging to screen for breast cancer, it opened up the diagnostic procedure to many more women.

Women at increased risk were recom mended to get annual breast MRI in addition to having regular clinical exams and annual mammograms, which are X-rays of the breast.

"With breast MRI, I think we now have the next step in terms of trying to understand and deal with this disease," said Dr. Gilda Cardenosa, director of breast imaging at Virginia Commonwealth University.

"It's rapidly evolving. What I am doing now is different from what I was doing six months ago." Technique and equipment are changing.

Among the groups of women considered at higher risk are those with a breast cancer gene mutation (BRCA1 or BRCA2), and women who have a 20 percent to 25 percent lifetime risk of breast cancer based on various factors.

"More patients that need it are starting to get approval from the insurance companies," Fidler said.

But it's also creating dilemmas.

More women are undergoing biopsies, an invasive procedure in which a sample of tissue is taken from a suspicious area or tumor and examined microscopically to see if the cells are cancerous.

Also, MRIs are picking up additional tumors in some patients already identified by mammography as having at least one tumor. That has experts questioning whether lumpectomies done to preserve the breast are really adequate treatment for some patients.

There is speculation that radiation and chemotherapy after surgery destroy any undetected tumors left behind. But many also wonder if treatment failure or breast cancer recurrence is the result of these undetected tumors and conservative treatments.

Researchers are trying to answer these questions and others as they wait for clear evidence that MRI will reduce breast cancer deaths. The specialists who treat breast cancer -- oncologists, surgeons and radiologists -- don't necessarily agree.

"We are clearly finding disease with MRI we are not finding with any other modality," said Cardenosa, speaking to a group of women's health providers at a meeting in Richmond recently on female cancers. Cardenosa agrees there are a lot of biopsies being done, but said it's to be expected as doctors learn the technology's strengths and limitations. There was a similar learning curve when mammography became the standard of care, she said.

MRI technology uses powerful magnets and radio waves to look inside the body, creating three-dimensional pictures that can be looked at layer by layer, or slice by slice. Enhanced areas show up when a contrast agent injected before the scan comes in contact with tissue different from surrounding tissue or abnormal tissue. MRI is better -- but about 10 times more expensive -- than traditional X-ray mammography at spotting suspicious areas. A mammogram costs about $100 compared to breast MRI's $1,500 cost.

"The concern was MRI is probably a better test, but are we going to have so many false-positives that the benefits of early detection of cancer are going to be outweighed by all these negative biopsies you are doing from false-positive MRIs," said Dr. Steven Harms, a researcher and radiologist at the University of Arkansas for Medical Sciences.

Harms, a speaker last fall at a breast cancer month event sponsored by the Ellen Shaw De Paredes Research Foundation, presented a number of patient cases in which breast MRI found tumors missed by mammography and also helped surgeons do tailored lumpectomies.

When used to find the extent of cancer, breast MRI can change treatment plans. He described one patient diagnosed with early-stage breast cancer confined to the milk ducts, or ductal carcinoma in situ. She had an MRI before a scheduled lumpectomy, which showed cancer thought to be about 2 centimeters was really about 7 centimeters.

"Normally you can't do a lumpectomy on somebody that has a 7-centimeter cancer," Harms said. "That's because when you think about doing a lumpectomy, you are usually thinking about taking out a ball of tissue. Well a 7-centimeter ball out of the breast is going to be so large that the cosmetic result is not going to be satisfactory."

Harms said using the MRI images, doctors tailored the lumpectomy to take out a longer, narrower area based on the margins of the cancer.

"It's kind of a cigar-shaped incisional biopsy," Harms said. "She had a very acceptable cosmetic result. That's our goal -- streamline the treatment, do the right treatment the first time, do better-quality care."

Cardenosa said in some cases what is seen on a mammogram is the "tip of the iceberg," with MRI sometimes showing more widespread disease -- or what could be disease.

"I am convinced the disease I am seeing in my patients today is disease that I just never knew about before. So how do you bring the information together."

Breast MRI is even causing some to rethink early stage ductal carcinoma in situ, or DCIS. MRI has shown that some types of DCIS calcifications show the same vascular growth as invasive cancers. One theory suggests that they are invasive cancers that grow ducts.