Can scintimammography with 99(m)Tc-MIBI identify multifocal and multicentric primary breast cancer?

Scintimammography with Tc-99m-MIBI has been shown to be an effective adjunc t to imaging of the breast with mammography. Uptake of Tc-99m-MIBI is parti cularly high in sites of non-calcified cancer and ductal carcinoma in situ (DCIS), and as a consequence it may be possible to use this method of imagi ng in identifying multifocal or multicentric disease. The aim of this study was to evaluate the efficacy of preoperative scintimammography in the dete ction of multifocal and multicentric breast cancer and compare these result s with mammography. A retrospective review was performed of 353 women image d with Tc-99m-MIBI as part of the clinical assessment of their suspected pr imary breast cancer. The results of the scintimammography and mammography w ere then compared with the final pathological diagnosis obtained after mast ectomy in all patients. Histopathological assessments of breast tissue from mastectomy confirmed 40 women (12%) had multifocal (34) or multicentric (s ix) breast cancer. Scintimammography correctly identified 39 of these cance rs and the multifocal or multicentric character of the cancer was identifie d in 22 (52%.) of these patients. Anatomical imaging performed in all 40 pa tients including 25 with mammography alone, mammography and ultrasound in 1 1 cases and ultrasound alone in four patients. Anatomical imaging identifie d cancer to be present in 28 patients (70%) and the combination of mammogra phy and ultrasound identified correctly that the cancer was multifocal or m ulticentric in eight patients (22%). In this study scintimammography was ab le to identify more cases of multifocal and multicentric cancer than mammog raphy and/or ultrasound. In patients where pre-operative identification of multicentric or multifocal disease can alter treatment scintimammography ma y be a useful investigative tool. ((C) 2001 Lippincott Williams & Wilkins).