Dr. Janice Sung and colleagues assessed breast MRI as a screening tool for detecting otherwise hidden breast cancers in women who had a history of radiation therapy to the chest. The study included 95 women with this prior history who had received a total of 253 breast MRI exams between January 1999 and December 2008. Most of these patients (81 out of 95, or 85%) had been treated for Hodgkin's disease with chest radiation.
"A number of studies performed at our institution involve screening women at high risk for breast cancer, including those with a history of chest irradiation," Sung told AuntMinnie.com. "Most of the studies that have demonstrated a higher sensitivity of screening MRI compared to mammography involved women at a high risk due to a family history or genetic mutation. We were interested in whether similar results would be seen in patients with a history of chest irradiation."
The age of each woman at the time of the first MRI ranged from 18 to 63; age at the time of radiation treatment ranged from 5 to 43. The mean interval between the chest radiation and the screening breast MRI was 16 years, the team wrote. Twenty-seven of the 253 breast MRI exams (11%) went to biopsy.
During the study period, 10 cancers were diagnosed in nine patients. Four of these cases were detected by MRI alone, three were detected by mammography alone, and three were detected by both mammography and MRI done on the same day. All of the cancers were in Hodgkin’s disease survivors.
"Screening MRI resulted in an incremental cancer detection rate of 4% among women with a history of prior chest irradiation," the team wrote. "Breast MRI will detect otherwise occult breast cancers in women with a prior history of chest irradiation and should be used in conjunction with mammography to screen these women."
