March 30, 2007

CONTACT: Olivia Fermano
(215) 349-5653

MRI Aids Cancer Detection in the Opposite Breast of Women
Newly Diagnosed with Breast Cancer

Adding MRI to Mammography and Clinical Breast Exam Doubles Number
of Opposite Breast Cancers Detected at Initial Diagnosis

(PHILADELPHIA) – One in every 10 women newly diagnosed with cancer in one breast will also develop the disease in the opposite breast. These opposite – or contralateral – breast cancers often take years to diagnose, which can increase patient anxiety, lower the chance of successful treatment, and lead to additional procedures.

A study conducted by the American College of Radiology Imaging Network (ACRIN) study published in the March 29th, 2007 issue of the New England Journal of Medicine helps establish magnetic resonance imaging (MRI) as a key component of the diagnostic workup for women at the time of initial breast cancer diagnosis.  The research, conducted at 25 institutions across the country, including the Abramson Cancer Center of the University of Pennsylvania, found the addition of an MRI scan led to the detection of more than 90 percent of cancers in the opposite breast missed by mammography and clinical breast exam, increasing the number of cancers detected. 

“I think MRI is a very good option,” said Mitch Schnall, MD, PhD, Matthew J. Wilson Professor of Radiology and senior author of the study. “It can provide peace of mind for women when they’re diagnosed. This study clearly shows that one in 30 women who think they have cancer in one breast after a traditional evaluation with mammography and clinical exam, actually have bilateral breast cancer that can be detected by MRI. Knowing this at the time of diagnosis of the first cancer has a significant impact on the approach to treatment.”

Supported by the National Cancer Institute (NCI), the ACRIN trial recruited 1,007 women across 25 sites, including Penn, who had a recent diagnosis in one breast and found that the added benefit of MRI was consistent – regardless of cancer type, age, and breast density.  Also, the diversity of medical facilities participating in the trial that recruited patients – from academic institutions, community hospitals, and imaging centers – suggests that the results can be generalized to other practices. 

In this study the MRI scan detected a variety of cancer types.  In general, those cancers were at an earlier stage than cancers found in other types of exams, which is important because breast cancers detected at an earlier stage are often more treatable.  

Researchers expect that if a MRI of the opposite breast is negative, women diagnosed with cancer in only one breast can more confidently opt against having a double mastectomy.  “Although no imaging tool is perfect, if the MRI is negative, the chance of cancer in that breast is extremely low.  A potential outcome that we would be delighted to see is fewer unnecessary bilateral mastectomies and fewer recurrences years after the initial cancer diagnosis," said Constance Lehman, MD, PhD, principal investigator of the ACRIN breast MRI trial, and Director of Breast Imaging at the University of Washington and Seattle Cancer Care Alliance.  The ACRIN trial also noted fewer “false positives,” or initial findings that later proved not to be cancer, than previous, smaller breast MRI studies had documented. 

According to the NCI, in the United States breast cancer is the most commonly newly diagnosed non-skin cancer in women, and the second leading cause of cancer-related death in women. In the United States in 2007, an estimated 178,480 women will be diagnosed with breast cancer, and an estimated 40,460 women will die of the disease. 

Researchers are also optimistic that MRI may lead to long term savings to patients and to the health care system. The fact that MRI can detect most cancers in both breasts prior to therapy may result in fewer rounds of chemotherapy and fewer breast surgeries. According to Schnall, “This study certainly points to future trials need for another, multi-center study that clearly demonstrates the ability of MRI to detect cancer not seen by mammography. Hopefully, this will lead to recommendations from the American Cancer Society for all women who fall into high risk categories for breast cancer to add MRI screenings to the arsenal in the fight against cancer."


PENN Medicine is a $2.9 billion enterprise dedicated to the related missions of medical education, biomedical research, and high-quality patient care. PENN Medicine consists of the University of Pennsylvania School of Medicine (founded in 1765 as the nation's first medical school) and the University of Pennsylvania Health System.

Penn's School of Medicine is ranked #2 in the nation for receipt of NIH research funds; and ranked #3 in the nation in U.S. News & World Report's most recent ranking of top research-oriented medical schools. Supporting 1,400 fulltime faculty and 700 students, the School of Medicine is recognized worldwide for its superior education and training of the next generation of physician-scientists and leaders of academic medicine.

The University of Pennsylvania Health System includes three hospitals, all of which have received numerous national patient-care honors [Hospital of the University of Pennsylvania; Pennsylvania Hospital, the nation's first hospital; and Penn Presbyterian Medical Center]; a faculty practice plan; a primary-care provider network; two multispecialty satellite facilities; and home care and hospice.

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