Breast MRI detects additional 'unsuspected' cancers not seen on mammography or ultrasound

Nearly 20% of patients with recently diagnosed breast cancer had additional malignant tumors found only by MRI, according to a study performed at Dartmouth Hitchcock Medical Center.

A total of 199 patients with newly diagnosed breast cancer underwent breast MRI. "We found additional, unsuspected cancers in the ipsilateral breast (the one that had already been diagnosed with cancer) in 16% of patients; we found cancers in the contralateral breast (the one that had not been diagnosed with cancer) in 4% of patients," said Petra J. Lewis, MD, lead author of the study. "These patients had already had bilateral mammography and these tumors had not been apparent on mammography," said Dr. Lewis.

"The detection of an unsuspected tumor is critical. These additional tumors in nearly a fifth of patients are tumors that can potentially grow and not be diagnosed until they are much larger—affecting the health and survival of the patients," she said.

"This study has been particularly helpful to us as clinicians because it gives us data we can discuss with patients when recommending breast MRI," said Dr. Lewis.

More information: This study appears in the May issue of the American Journal of Roentgenology.

Source: American Roentgen Ray Society