Indications for breast magnetic resonance imaging. Consensus document "Attualità in senologia", Florence 2007.

The clinical use of breast magnetic resonance (MR) imaging is increasing, especially for applications requiring paramagnetic contrast-agent injection. This document presents a synthetic list of acceptable indications with potential advantages for women according to evidence from the literature and the expert opinion of the panel that developed this statement. We generally recommend that breast MR imaging be performed in centres with experience in conventional breast imaging [mammography and ultrasonography (US)] and needle-biopsy procedures (under stereotactic or US guidance) as well as in breast MR imaging and second-look US for findings not revealed by conventional imaging performed before MR imaging. In our opinion, there is no evidence in favour of breast MR imaging as a diagnostic tool to characterise equivocal findings at conventional imaging when needle-biopsy procedures can be performed, nor for the study of asymptomatic, non-high-risk women with negative conventional imaging. After a description of technical and methodological requirements, we define the indications and limitations of breast MR imaging for surveillance of high-risk women, local staging before surgery, evaluation of the effect of neoadjuvant chemotherapy, breast previously treated for carcinoma, carcinoma of unknown primary syndrome, nipple discharge and breast implants.

What is the sensitivity of mammography and dynamic MR imaging for DCIS if the whole-breast histopathology is used as a reference standard?

PURPOSE: Our purpose was to compare mammography and dynamic contrast-enhanced magnetic resonance imaging (MRI) in the detection of ductal carcinoma in situ (DCIS). MATERIALS AND METHODS: Ninety patients (aged 58.6+/-16.1 years) who were candidates for unilateral (n=81) or bilateral (n=9) mastectomy underwent mammography and dynamic contrast-enhanced breast MRI using a coronal three-dimensional gradient-echo sequence with slice thickness < or =3 mm before and after intravenous injection of gadoteridol (0.1 mmol/kg). Mammographic and MR images were evaluated by two offsite readers working in consensus. Pathological examination performed on 5-mm sections covering the whole breast was used as a reference standard. RESULTS: Out of 99 breasts, pathology revealed 26 DCIS in 14 breasts of 14 patients, aged 52.0 +/- 9.6 years. Lesion diameter at pathology was <5 mm (n=4); > or =5 and <10 mm (n=7); > or =10 and <20 mm (n=3); > or =20 mm (n=2); not assessed (n=10). Sensitivity was 35% (9/26) for mammography and 38% (10/26) for MRI (not significant difference, McNemar test). Both mammography and MRI provided a true positive result in seven cases (four of them measured at pathology, with a diameter of 20.0+/-12.9 mm; median 20 mm) and a false negative result in 14 cases (10 of them measured at pathology, with a diameter of 4.2+/-1.9 mm; median 4.6 mm) (p=0.024, Mann-Whitney U test). Only 46% (12/26) of DCIS were detected at mammography and/or MRI; the remaining 54% (14/26) were diagnosed only at pathological examination. CONCLUSIONS: When the whole breast is used as the histopathological reference standard, both mammography and MRI show low sensitivity for DCIS.

Dynamic breast magnetic resonance imaging without complications in a patient with dual-chamber demand pacemaker.

Mammography and ultrasound indicated a cancer of the right breast in a 77-year-old woman with a dual-chamber demand pacemaker. The patient was not pacemaker-dependent. She underwent breast 1.5T magnetic resonance imaging (MRI) (dynamic gradient echo sequence with Gd-DOTA 0.1 mmol/kg). Before the patient entered the MR room, the configuration of the device was changed (the response to magnet was switched from asynchronous to off and the rate-responsive algorithm was disabled). No relevant modifications of heart rhythm or rate were observed during the MR examination. No symptom was reported. Immediately after the examination, the pacemaker interrogation showed neither program changes nor alert warnings. MRI detected a bifocal cancer in the right breast which allowed tailored breast-conserving treatment to be initiated. Histopathology confirmed a bifocal invasive ductal carcinoma.