TC-99(M)-SESTAMIBI SCINTIMAMMOGRAPHY IN PATIENTS WITH SUSPICIOUS BREAST-LESIONS - COMPARISON OF SPET AND PLANAR IMAGES IN THE DETECTION OF PRIMARY TUMORS AND AXILLARY LYMPH-NODE INVOLVEMENT

Planar scintimammography with Tc-99(m)-sestamibi (Tc-90(m)-MIBI) has b een shown to be useful in diagnosing breast carcinoma. The aim of this study was to compare single photon emission tomography (SPET) and pla nar imaging for scintimammography with Tc-99(m)-MIBI in the detection of primary breast cancer and axillary lymph node involvement. Sixty-th ree females with mammographically suspicious lesions and 12 controls w ere evaluated. Dynamic images were acquired commencing immediately aft er the injection of the radiopharmaceutical, followed by multiple plan ar images in the supine and prone positions plus SPET supine imaging. A final histopathological diagnosis was achieved after surgery. A tota l of 66 breast lesions were considered. No focal uptake of (99)c(m)-MI BI was observed in tile breasts or axillas of the controls. In the pat ients with breast cancer, the sensitivity was 92.9% (30/42) for SPET, 71.4% (30/42) for supine and 85.7% (36/42) for prone planar imaging, r espectively; the specificity was 87.5% for SPET and 91.6% for the plan ar scans. Metastatic axillary lymph node involvement was seen in 19 pa tients: the sensitivity was 84.2% (16/19) for SPET and 63.2% (12/19) f or planar images; the specificity was 91.3% and 95.7% respectively. Ou r results confirm the high diagnostic accuracy of Tc-99(m) scintimammo graphy in the diagnosis of breast cancer, and suggest that SPET is mor e sensitive than planar images, especially in detecting axillary lymph node involvement.