Multicentric Cancer Detected at Breast MR Imaging and Not at Mammography: Important or Not?

Abstract

).q RSNA, 2015 Purpose:To review the magnetic resonance (MR) imaging and pathologic features of multicentric cancer detected only at MR imaging and to evaluate its potential biologic value. Materials and Methods:This retrospective study was institutional review board approved and HIPAA compliant; informed consent was waived. Results:Known index cancers were more likely to be invasive than MR imaging-detected multicentric cancers (88% vs 76%, P = .023). Ductal carcinoma in situ (21 of 87 lesions [24%]; 95% CI: 15, 36) represented a minority of additional MR imaging-detected multicentric cancers. Overall, the size of MR imaging-detected multicentric invasive cancers (median, 0.6 cm; range, 0.1-6.3 cm) was smaller than that of the index cancer (median, 1.2 cm; range, 0.05-7.0 cm; P = .023), although 17 of 73 (23%) (95% CI: 14, 35) patients had larger MR imaging-detected multicentric cancers than the known index lesion, and 18 of 73 (25%) (95% CI: 15, 36) had MR imaging-detected multicentric cancers larger than 1 cm. MR imaging-detected multicentric cancers and index cancers differed in histologic characteristics, invasiveness, and grade in 27 of 73 (37%) patients (95% CI: 26, 49). In four of 73 (5%) patients (95% CI: 2, 13), MR imaging-detected multicentric cancers were potentially more biologically relevant because of the presence of unsuspected invasion or a higher grade. Conclusion:Multicentric cancer detected only at MR imaging was invasive in 66 of 87 patients (76%), larger than 1 cm in 18 of 73 patients (25%), larger than the known index cancer in 17 of 73 patients (23%), and more biologically important in four of 73 women (5%). An unsuspected additional multicentric cancer seen only at MR imaging is likely clinically relevant disease.q RSNA, 2015

Predictive value of breast magnetic resonance imaging in detecting mammographically occult contralateral breast cancer: Can we target women more likely to have contralateral breast cancer?

“…Similar to other recently published studies, we found that the majority of MRI‐detected, mammographically occult CBC were diagnosed as stage 0 or stage IA, with DCIS representing over a third of all CBC. This may have significant clinical implications in the modern era of DCIS management.…”

“…Furthermore, our study to some degree refutes the notion that MRIs are most effective as an adjunct to staging for women with dense or extremely dense breasts; we found that a third of CBC was detected in patients with breasts mammographically described as fatty or with scattered fibroglandular densities, higher than reported by Iacconi et al 25 who published that MRI detected mammographically occult ipsilateral multicentric disease more frequently in patients with heterogeneously or extremely dense breasts. 25 We acknowledge limitations to this study.…”

Factors associated with MRI detection of occult lesions in newly diagnosed breast cancers

“…9,10 MRI detection rates of otherwise occult contralateral breast cancer range from 3.1% to 5.5%, 10,11 while detection rates for occult multicentric disease have been reported to be as high as 3.6%. 12 In a previous publication from our group, which included neoadjuvant patients, the rate of occult cancer detection was 7.5%. 13 In the current study, we found detection rates of additional lesions by MRI that were similar to those of previous studies, resulting in rates of detection of 6.2% for occult multifocal cancers, 1.9% for occult multicentric cancers, and 3.1% for occult contralateral cancers.…”

“…Recent meta‐analyses cite MRI detection rates of additional disease ranging from 16% to 20% 9,10 . MRI detection rates of otherwise occult contralateral breast cancer range from 3.1% to 5.5%, 10,11 while detection rates for occult multicentric disease have been reported to be as high as 3.6% 12 . In a previous publication from our group, which included neoadjuvant patients, the rate of occult cancer detection was 7.5% 13 .…”

Breast Magnetic Resonance Imaging-Guided Biopsy

“…In addition, breast MRI most accurately depicts the extent of breast cancer (4)(5)(6). Although the clinical relevance of additional lesions is still controversial, preoperative MRI identifies more synchronous, ipsilateral or contralateral breast cancers than mammography and ultrasound (7)(8)(9).…”