MRI and breast cancer screening

http://www.medpagetoday.com/reading-room/asco/brea...

"A recent study by Constance Lehman et al at Massachusetts General Hospital sheds valuable light on this issue. The investigators reviewed 1,521 cases of women who underwent screening MRI for either a personal history of breast cancer or a strong risk for developing breast cancer. Interestingly, these researchers found that there was a lower false-positive rate and higher specificity in women undergoing breast MRI for a personal history rather than for high-risk screening. This trend was preserved even after 5 years of surveillance, as 57% of the women in this study had a secondary breast cancer diagnosed in this time frame.

Looking at the data more closely, certain features made false-positive MRI findings less likely -- namely, older age and a history of prior breast MRI for comparison. We can assume that this is likely due to less dense breasts at an older age and the availability of baseline MRIs to make more precise judgments. Another important point in this study is that all of the cancers detected by breast MRI were node negative and smaller than 2 cm.

The ability to detect occult tumors while they are small and non-nodal, beyond 5 years from initial treatment, makes breast MRI appear to be superior to standard mammogram in women with a prior history of breast cancer. Therefore, in this population, breast MRI certainly lends itself towards enhanced, effective surveillance."