Analysis: Wider Imaging for Breast Cancer

Mar 28, 05:31 PM

Current Headlines: By ED SUSMAN

Women diagnosed with breast cancer should be screened with magnetic resonance imaging for cancer in the other breast, researchers said Wednesday.

As many as 3 percent of women may have cancer in the second breast, said Constance Lehman, professor of radiology at the University of Washington, Seattle, in an article to be published in Thursday's editions of the New England Journal of Medicine.

Magnetic resonance imaging can detect cancer in the contralateral breast that is missed by mammography and clinical examination at the time of the initial breast-cancer diagnosis, Lehman said.

She said that the imaging detected cancer in the other breast in 30 of 969 women. The images seen when the second breast was examined resulted in 121 of the women undergoing a biopsy, and nearly a quarter of those women had cancer that had not been detected.

Lehman said that those findings were significant in that 18 of the 30 cancers found in the other breast were a form of invasive cancer. The average diameter of the cancers found by the imaging procedure was about 11 mm -- less than half an inch long.

Lehman enrolled women in the study who had been diagnosed with breast cancer within 60 days before the study MRI was performed. The aim of the study was not to compare imaging methods but to determine if further imaging in women diagnosed with cancer could find other tumors that were missed due to limitations of mammography and physical examination, Lehman said.

The average age of the women in the study was 53, and 90 percent of the participants were white. About 57 percent of the women were post-menopausal.

In our study, all of the cancers that were detected by means of magnetic resonance imaging were (lymph) node-negative, and 40 percent were ductal carcinomas in situ, she said, indicating that these cancers were detected early.

The success of screening programs for breast cancer lies in their ability to detect early cancer, before it has spread to lymph nodes or metastasized to distant sites. Recent studies provide support for the benefit of detecting ductal carcinoma in situ, since this tumor is likely to progress to invasive disease if left untreated, Lehman said.

I tell all my surgeons who have patients who are scheduled for breast cancer to perform (MRI) on both the same breast where cancer has been diagnosed and on the other breast as well, Kristin Byrne, chief of breast imaging at Lenox Hill Hospital in New York, told United Press International.

Magnetic resonance imaging is the most sensitive breast imaging devices that we have, Byrne said. We have had cases in which a woman who was scheduled for breast conserving surgery or lumpectomy had an imaging study of the same breast which found more extensive cancer. Instead of the breast conservation surgery, she required a mastectomy.

Byrne said it is important for women to have MRI imaging at institutions that can also conduct a biopsy and have upgraded systems that can provide high quality imaging. She said that when women arrive at her hospital with MRI scans from other facilities, it is almost always required that she undergo the entire imaging procedure again.