title: Primary breast cancer imaging with technetium-99m sestamibi and its relation with P-glycoprotein overexpression.
abstract: The aim of this preliminary study was to evaluate retrospectively sestamibi scintigraphy in relation to the presence of the 170-kDa P-glycoprotein (Pgp), which represents an expression of multidrug resistance in patients with primary breast cancer. Fifteen women (age range 37-76 years) were referred for technetium-99m sestamibi scintigraphy because of suspicious breast lesions detected by mammography and ultrasonography, and subsequently assessed by fine-needle aspiration. Scintigraphy was performed 30 min following the injection of 500 MBq 99mTc-sestamibi. Three planar anterior and oblique images were obtained with the patient in the supine position. Excised tumours were assessed for cytosolic CA 15.3, oestrogen (OR) and progesterone (PR) receptors and c-erb B2 neu oncogene. Pathology revealed that only 13 of the 15 patients had malignant tumours. The two benign tumours were sestamibi-negative and Pgp-positive. Sestamibi scintigraphy was positive in 10 of the 13 malignant lesions (including nine of ten infiltrating ductal carcinomas). Two of the three lesions with false-negative scintigraphy were Pgp-negative; in one of these cases histology revealed an invasive lobular carcinoma and in the other, mucinous adenocarcinoma. The third false-negative lesion was a Pgp-positive infiltrating ductal carcinoma which was c-erb B2 neu-negative but CA 15.3-, OR- and PR-positive. This preliminary study confirms that the resistance to chemotherapy which may occur in patients with primary breast cancer can be a cause of negative sestamibi scintigraphy.
authors: Médicine Nucléaire, CHU Bobigny, Paris, France.
authors: J L
authors: JL
authors: Moretti
authors: H
authors: H
authors: Azaloux
authors: D
authors: D
authors: Boisseron
authors: J C
authors: JC
authors: Kouyoumdjian
authors: J
authors: J
authors: Vilcoq
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000096:biosynthesis*; D000368:Aged; D001943:Breast Neoplasms / Q000000981:diagnostic imaging* / Q000235:genetics; D005069:Evaluation Studies as Topic; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008875:Middle Aged; D011877:Radionuclide Imaging; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D017256:Technetium Tc 99m Sestamibi
chemical_list: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D017256:Technetium Tc 99m Sestamibi