Dynamic gradient-echo and fat-suppressed spin-echo contrast-enhanced MRI of the breast.

PURPOSE: To evaluate heavily T2-weighted, dynamic contrast-enhanced and fat-suppressed magnetic resonance imaging (MRI) of the breast in comparison with conventional imaging and fine needle aspiration cytology (FNAC). PATIENTS AND METHODS: Fifty patients with surgically/pathologically proven breast disease were examined pre-operatively by MRI. The majority, 45 patients, had invasive carcinoma. T1-weighted spin-echo, T2-weighted fast spin-echo (with chemical-shift-selective fat-suppression in 20 cases), rapid dynamic contrast-enhanced gradient-echo and post-contrast fat-suppressed T1-weighted images were obtained. Signal intensity changes during dynamic scanning were assessed qualitatively and quantitatively. Comparison was made with the results of X-ray mammography, ultrasound and fine needle aspiration cytology. RESULTS: Unenhanced MRI was inadequate for determining the location, extent or nature of most lesions even when fat-suppressed T2-weighted images were obtained. Following contrast injection, there was significantly greater enhancement of invasive carcinomas than normal parenchyma. Invasive carcinomas of ductal and lobular subtypes did not differ significantly in their enhancement profiles. Prominent enhancement of the lesion periphery, which was a feature in 33 out of 50 cases (the majority of which were invasive carcinomas) was not due to central tumour necrosis. In four cases, invasive carcinomas which were clearly visible on early dynamic scans could not be identified on post-contrast fat-suppressed images. Lesions that were more numerous or extensive than had been recognised clinically or mammographically were revealed by MRI in 14 patients, though MRI was no more specific than conventional assessment. Invasion of the chest wall was accurately predicted by MRI in three cases. There was excellent correlation between tumour size shown by MRI and histopathology. FNAC was accurate in predicting the final histological diagnosis except in those cases where samples were unsatisfactory. CONCLUSIONS: Contrast-enhanced MRI appears useful in the assessment of suspected malignant breast masses, especially in younger women with predominantly glandular breast tissue. Specificity is no better than FNAC but tumour extent and multifocality are more accurately disclosed than by conventional imaging techniques. Contrast-enhanced chemical-shift-selective fat-suppressed images are sub-optimal in a small proportion of cases (particularly where lesions are located posteriorly) and some benign breast disease may appear misleadingly conspicuous on such images. Morphological features and quantification of lesion enhancement during dynamic scanning presently offer only limited prospects for discrimination between various pathologies. Heavily T2-weighted sequences appear of marginal value.

Dynamic contrast-enhanced and fat suppressed magnetic resonance imaging in suspected recurrent carcinoma of the breast: preliminary experience.

20 women with suspected recurrent breast cancer who had undergone previous breast-conserving operations were investigated using dynamic contrast-enhanced gradient echo (GRE) and fat suppressed spin echo (SE) magnetic resonance (MR) imaging. Histologically confirmed recurrent tumour was readily recognized on dynamic GRE scans by virtue of rapid, early and avid enhancement. Benign scars enhanced more slowly and reached lower magnitudes of enhancement. Fat suppressed SE images, which were typically acquired 10 min after contrast administration, were sensitive for the detection of tumour recurrence but lacked specificity. Early scanning after contrast administration offers the best prospects for distinguishing tumour recurrence from benign scarring. The criteria used to distinguish these two entities are highly dependent on the scan technique and the time at which images are obtained post-contrast.

Results of the first year of breast cancer screening in a district hospital.

The Humberside Breast Screening Service completed 1 year of screening by October 1990; 16,534 women were invited of whom 12,832 (77.6 per cent) attended. A group of 644 women (5.0 per cent) were called for further assessment and of these 134 underwent 135 primary surgical procedures. After assessment 25 were shown before operation to have cancer. One hundred and nine women had suspicious lesions and proceeded to surgical biopsy; 50 lesions proved malignant (benign: malignant biopsy ratio 1.2:1). The 75 malignant lesions represented a prevalence of 5.8 per 1000 of the screened population. Invasive cancer > 1 cm in diameter formed almost half of the malignant lesions. This service has cost 32 pounds per woman screened or 5533 pounds per cancer detected. The results are comparable to those of previous studies and suggest that a mammographic screening service can be successfully provided in a district hospital setting.

Outpatient arteriography--a safe and practical proposition?

Ninety-five patients, who underwent fine catheter peripheral angiography as outpatients, were followed up and assessed to determine the safety of this procedure. No patients reported any major side effects and in particular no patients experienced a rebleed from the arterial puncture site. This procedure could be safely adopted in any radiology department.