IMMUNOHISTOLOGIC ASSESSMENT OF TECHNETIUM-99M-MIBI UPTAKE IN BENIGN AND MALIGNANT BREAST-LESIONS

This study was undertaken to assess the relationship between the degre e of Tc-99m-MIBI uptake in breast lesions and the following histologic factors: neovascularity, desmoplastic reaction, cellular proliferatio n and mitochondrial density. Methods: Forty-two patients who previousl y underwent MIBI breast imaging (4 false-negative, 12 false-positive, 15 true-negative, 11 true-positive) were studied. Immunohistochemical staining was performed for neovascularity (Factor VIII antigen), desmo plasia (alpha-actin antigen), mitochondrial density (mitochondrial ant igen) and cellular proliferation (MIB-1 antigen). The degree of micros copic staining was correlated with region of interest measurements of MIBI uptake on scintigraphy. Results: There was a poor correlation bet ween MIBI uptake and the degrees of neovascularity (r = 0.08, p > 0.05 ) and intracellular mitochondrial density (r = 0.04, p > 0.05) while t here was a moderate correlation with cellular proliferation (r = 0.4, p < 0.05) and desmoplasia (r = 0.55, p < 0.001). Conclusion: The degre e of MIBI uptake in breast lesions is multifactorial, but it appears t o be related more to the degree of desmoplastic activity and cellular proliferation than neovascularity and mitochondrial density.