Increasing use of preoperative breast MRI has been associated with significant increases in bilateral cancer diagnoses and subsequent invasive surgeries with questionable long-term benefits, according to a study published online Aug. 14 in Breast Cancer Research and Treatment.
Study authors Cary Gross, MD, of Yale School of Medicine, and colleagues noted that breast conserving therapy is the preferred option for women with early stage breast cancer when feasible.
“Patient concern about recurrence and survival must be balanced with the increased risk for complications associated with more aggressive cancer surgery, particularly when there is no proven benefit of the more aggressive option," Gross said in a press release.
The researchers based their findings on an analysis of more than 72,000 women, ages 68-94, in the Surveillance, Epidemiology and End Results-Medicare database. All women in the study cohort were diagnosed with breast cancer from 2000 to 2009 and underwent surgery. Gross and colleagues identified which patients received preoperative breast MRI and how this affected surgical approach.
Over the course of the study period, use of preoperative breast MRI jumped from a rate of 0.8 percent in 2000-2001 to 25.2 percent in 2008-2009. While the overall rate of mastectomy in the cohort was 43.3 percent, the authors found that MRI was associated with an increase likelihood of having a mastectomy compared with breast conserving surgery, with an adjusted odds ratio of 1.21.
Among women who underwent mastectomy, 12.5 percent had bilateral mastectomy after undergoing an MRI scan, compared with 4.1 percent who did not have an MRI. The study also found that women undergoing MRI were more likely to have both breasts removed when cancer was found in only one breast—called contralateral prophylactic mastectomy—compared with those who did not receive a breast MRI.
"These data are concerning because the long-term benefits associated with bilateral mastectomy for older women with breast cancer are unclear," added Gross.