Performance of DWI as a Rapid Unenhanced Technique for Detecting Mammographically Occult Breast Cancer in Elevated-Risk Women With Dense Breasts

Abstract

In elevated-risk women with dense breasts, DWI can reveal cancers in addition to those detected on mammography alone with a low false-positive rate; these results suggest that DWI may have potential as a rapid supplemental screening tool.

Visibility of mammographically occult breast cancer on diffusion-weighted MRI versus ultrasound

“…Evaluation of specificity is of interest because a major concern of whole breast ultrasound screening is its low specificity, and, therefore, high false positive biopsy rate (18–24,48). However, DWI specificity was reported by a prior blinded reader study as 91% (32), which is higher than that reported for whole breast screening ultrasound (84%) (18). …”

“…Lesion visibility on DWI was scored visually on a scale of 1–5 by three independent readers based on signal strength and focality of the signal, as described in prior studies (32,33) and detailed in Table 1. Examples are shown in Figure 1.…”

“…Subsequently, multiple studies demonstrated DWI’s ability to differentiate breast malignancy from benign lesions, as summarized by two meta-analyses demonstrating pooled sensitivities/specificities of 84%/79% and 86%/76% respectively (27,28). Perhaps most importantly, DWI has also been shown to identify mammographically occult disease (29–32). However, while there have been a number of studies comparing the sensitivities of DWI versus DCE-MRI, there are few data comparing DWI and ultrasound for breast cancer detection.…”

Diffusion-weighted breast MRI: Clinical applications and emerging techniques

“…More recently, McDonald et al evaluated the performance of DWI to detect mammographically occult breast cancers specifically in women with dense breasts. This study showed that DWI has the potential to identify as many as eight additional cancers over mammography per 1000 women screened, with reasonable specificity and positive predictive value (91% and 62%, respectively) . Technical optimizations of diffusion weighting and other imaging factors can further improve breast cancer detectability on DWI .…”

“…There may also be a role for DWI as an alternative to contrast‐enhanced MRI for breast cancer screening . Early investigations showed many mammographically and clinically occult breast cancers are visible on DWI and exhibit low ADC values, Figure .…”