contents TIB 2 SA JOURNAL OF RADIOLOGY • October 2005 EDITORIAL MR breast imaging - does it have a place in your practice? Peter Corr FFRad (D) SA Department of Radiology University of KwaZulu-Natal and Inkosi Albert Luthuli Hospital Durban The incidence of breast cancer appears to be increasing worldwide, especially in Westerncountries, and also in South Africa. The demand among patients for breast cancer screen- ing is increasing as they become better informed about the benefits of early detection. Radiologists have an important role to play in educating patients on the benefits of breast screening for cancer. MR breast imaging shows great promise for the early detection of can- cer in mammographically dense breasts found in some younger women. The sensitivity of MR approaches 100% for invasive malignancy, but it is lower for intraductal cancer, varying between 40% and 100%.1 However the specificity for cancer is much lower, ranging from 37% to 70% in most series.1 This is due to comparing different study populations, different imag- ing protocols, and different interpretation criteria. However, to confound the issue further it is important to remember that the normal breast parenchyma can enhance focally following gadolinium injection in pre-menopausal women.2 Contrast enhancement is minimal in days 7 - 20 of the menstrual cycle and this is the best time to image the breast using MR. 3 The role of breast MR imaging is not yet clearly defined in relation to mammography and ultrasound but it is important in solving difficult cases with equivocal mammogram and ultrasound findings. It has been demonstrated to be superior to other modalities in accurately determining the tumour stage for preoperative staging and detecting multifocal tumour involvement.1 It is useful in detecting residual or recurrent tumour following lumpectomy if the study is performed 28 days or more following the surgery.4 MR is especially useful in detecting invasive lobular cancer, which is often multifocal or bilateral. Lobular cancer does not usually demonstrate a desmoplastic response and this makes detection more difficult on mammography.1 Breast MR imaging has been demonstrated to be more sensitive than screen- ing mammography in the detection of familial cancer which may be multifocal in patients who are BRCA1 or 2 positive or who have a strong family history of breast cancer.5 As in all investigations, good technique is essential for diagnostic studies. Fat suppression techniques and gadolinium enhancement are critical in detecting small cancers. New tech- niques are appearing on the diagnostic horizon, namely MR elastography and MR multivox- el spectroscopy. MR elastography is an interesting technique being investigated in Germany to stage breast cancer accurately. This technique images the elastic properties of the breast to detect any desmoplastic response from occult cancers.6 There is a steep learning curve for radiologists interpreting MR breast studies. The best results are achieved working in a multidisciplinary team together with breast surgeons, oncol- ogists and pathologists. 1. Lee C. Problem solving MR imaging of the breast. Radiol Clin North Am 2004; 42:919-934. 2. Kuhl C, Bieling HB, Gieseke J, Kreft BP, Sommer T, Lutterbey G. Healthy premenopausal breast parenchyma in dynamic contrast enhanced MR imaging of the breast: normal contrast medium enhancement and cyclical phase dependency. Radiology 1997; 203:137-144. 3. Muller-Schimpfle M, Ohmenhauser K, Stoll P, Dietz K, Clauseen CD. Menstrual cycle and age: influence on parenchymal contrast enhancement in MR imaging of the breast. Radiology 1997; 203:145-149. 4. Frei KA, Kinkel K, Bonel HM, Lu Y, Esserman LJ, Hylton NM. MR imaging of the breast in patients with positive margins after lumpectomy: influence of the time interval between lumpectomy and MR imaging. Am J Roentgenol 2000; 175:1577-1584. 5. Kuhl CK, Schmutzler RK, Leutner CC, Kempe A, Wardelman E, Hocke A. Breast MR imaging screening in 192 women proved or suspected to be carriers of a breast cancer susceptibility gene; preliminary results. Radiology 2000; 215:267-269. 6. Sinkus R, Tanter M, Catheline S, et al. Imaging anisotropic and viscous properties of breast tissue by MR elastog- raphy. Magn Reson Med 2005; 53:372-387. Peter Corr Guest Editor pg2 9/28/05 1:23 PM Page 1