MRI, scintimammography and histology in the assessment of multi-focal breast cancer

Abstract

Background and aim: MRI and scintimammography of the breast play a valuable role in patients with equivocal findings in breast imaging. The aim of this study was to evaluate the efficacy of preoperative scintimammography and MRI in the detection of multi-focal breast cancer and compare these results with histology. Methods: Twenty-nine patients underwent contrast enhanced MRI and scintimammography. MRI was performed on 1.3 or 1.5 T magnet, with rapid imaging performed after bolus injection of Gd-DTPA. Radionuclide imaging was performed 5–10 min after an intravenous injection of 740 MBq 99mTc-MIBI. The results were compared with histopathology. The histology examination was performed on the mastectomy specimens (10 mm slices) with 1 mm slices at any site of abnormality. Results: Invasive cancer was confirmed in 29 patients. MRI identified 8 as unifocal, 12 as multifocal, 4 as post-surgical changes/recurrence, 1 intraductal. 99mTc-MIBI identified 13 as unifocal, 12 as multifocal and 2 as normal. On pathological examination only 7 were confirmed as multifocal. Conclusion: MRI and 99mTc-MIBI scintimammography both over-identify multifocal disease and therefore care must be taken in using these techniques to plan surgery.