Molecular Breast Imaging as a Cost Effective Diagnostic Tool for Breast Cancer.

Abstract

Introduction: Molecular breast imaging (MBI), also referred to as breast specific gamma imaging (BSGI), utilizes nuclear medicine imaging with technetium 99-sestamibi to demonstrate metabolic activity of breast tissue. A focused gamma camera is used to assist in detecting lesions concerning for malignancy based on abnormal radiotracer uptake. MBI is performed with the patient in a sitting position and requires less breast compression than mammography. MBI is safe for patients with implanted metallic devices and renal disease. Facility charge for MBI is approximately $600 vs. $2500 for magnetic resonance imaging (MRI).Methods: IRB approval was obtained prior to study initiation. Forty four (44) patients underwent MBI with technetium 99-sestamibi after mammography and or ultrasound detected abnormalities for which biopsy was recommended.Results: Forty four (44) women ranging in age from 28 to 82 (median age 52) were found to have abnormal mammogram and or ultrasound findings requiring image guided biopsy. Prior to biopsy, MBI was performed. Fifteen MBI's were interpreted as demonstrating areas concerning for malignancy. Nine of the 44 patients (20.5%) demonstrated malignancy on biopsy pathology. Eight of these nine patients had positive MBI findings concerning for malignancy (88.9%). The patient whose MBI did not demonstrate findings consistent with malignancy had two sites of DCIS. The positive predictive value of these results was 53.3% and the negative predictive value was 96.55%.Conclusions: MBI shows promise in evaluating patients with abnormal mammogram or ultrasound findings. MBI is available at a much lower cost than MRI ($600 vs. $2500), which would have resulted in savings of $83,600 in this study alone. MBI can be used in patients for whom MRI is not an option such as claustrophobic patients, patients with renal disease limiting use of gadolinium contrast and patients who for other reasons such as body habitus and implanted metallic devices are not candidates for MRI. Further studies evaluating MBI are warranted to determine what role it may play in providing additional diagnostic data about patients with abnormal mammograms or ultrasounds. The role of MBI in settings where breast MRI is not available, is not technically feasible or is not an option due to cost also warrants further evaluation. Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 5014.