Abstract
We prospectively studied a total of 33 patients (5 benign, 28 malignant) with breast mass to evaluate the degree of accumulation of 99mTc-MIBI on scintigraphy. The axillary and breast lesions were evaluated in all patients. All patients had excisional biopsy or surgery after 99mTc-MIBI scintigraphy. The sensitivity of 99mTc-MIBI scintigraphy for malignant tumor was 96% (27/28), but specificity was 100% (5/5). The sensitivity for axillary lymph node metastasis was 58% (7/12), but specificity was 100% (14/14). Loss of 99mTc-MIBI uptake in lesions in delayed image which was considered to be due to wash out, was seen 14 of 39 lesions (36%) and was probably related to multidrug resistance. 99mTc-MIBI scintigraphy was able to diagnose this malignancy. This study showed that 99mTc-MIBI scintigraphy had a high diagnostic accuracy for the detection of primary breast cancer axillary lymph node metastasis.
