CAN SCINTIMAMMOGRAPHY REDUCE UNNECESSARY BIOPSIES

99Tc-sestamibi prone scintimammography (SMM) is a new, noninvasive met hod of imaging breast tumors. A pilot study has suggested that SMM inc reases the specificity of mammography, and that SMM could be used as a n adjunct to mammography to reduce the number of mammographically indi cated biopsies. The goal of this study was to further evaluate the eff icacy of SMM in diagnosing or excluding breast carcinoma. This was a p rospective case series with each patient serving as her own control. A ll subjects who had an abnormal mammogram, a palpable breast mass, or both were eligible for inclusion. All patients underwent breast examin ation, conventional mammography, SMM, and breast biopsy. Of the 81 wom en originally enrolled, 79 women with 80 lesions completed the study. SMM produced the following results: a sensitivity of 81 per cent, a sp ecificity of 81 per cent, a positive predictive value of 61 per cent, and a negative predictive value of 92 per cent. These values were sign ificantly lower than the pilot study results at a power of 80 per cent and P = 0.05. Our results indicate that SMM does not increase the spe cificity of conventional mammography and has a low negative predictive value. We would not recommend it as a screening technique to avoid bi opsy.