Technetium-99m sestamibi: an indicator of breast cancer invasiveness.

As recently shown, angiogenesis is the most reliable marker of breast cancer invasiveness. Unfortunately it must be assessed by immunohistochemistry on tissue specimens. We have used technetium-99m sestamibi, a marker of regional blood flow in other organs that often but not always images breast cancer, to assess the invasiveness of this tumour. Nineteen patients, ten with nodal metastases and nine without any metastases, were studied with 99mTc-sestamibi scintigraphy before operation. Angiogenesis was quantitatively assessed by immunohistochemical staining of endothelia for factor VIII. All the node-positive (N+) patients at surgical revision showed a positive 99mTc-sestamibi scan of the primary tumour and all the N-patients were negative. Nine out of ten N+ and sestamibi-positive tumours showed more than 135 microvessels/mm2 and one showed 99 microvessels/mm2; by contrast there were 71.6 +/- 12.1 microvessels/mm2 in the nine N- and sestamibi-negative tumours. Our study suggests that 99mTc-sestamibi is a marker of breast cancer invasiveness: its uptake is related to angiogenesis and, possibly, to oxidative metabolism of the tumour.

[Imaging in atherosclerosis: scintigraphy techniques]. / Imaging nell'aterosclerosi: tecniche scintigrafiche.

Noninvasive detection of atherosclerotic plaques remains a major challenge for clinical diagnosis, therapy and prognosis. Several approaches have been explored as a tool for thrombus imaging, using platelets, antiplatelet antibodies and fibronectin or as a direct metabolic marker as low density lipoproteins or photophrine II. We tested the affinity of a new F(ab')2 monoclonal antibody (TRF1) against human fragment D-dimer of cross-linked fibrin, for atherosclerotic plaques free of detectable thrombi on their surface. Six atherosclerotic segments of carotid and femoral arteries, and (as a control) 5 segments of atherosclerosis-free internal mammary artery, were drawn from 11 male patients undergoing bypass surgery. All segments were carefully washed in order to dissolve and remove possible endoluminal thrombi, and were subsequently cut to obtain couples of fragments of intima of similar weight, containing atherosclerotic plaques (n 16), or fatty streaks (n 12), or normal endothelium (n 20). Each fragment was separately put into a radioimmunoassay vial, and underwent a direct binding test to TRF1, or to an aspecific antibody, which both were labelled with 125I. The activity present in each fragment was measured with a gamma-counter after 3 h of incubation at 37 degrees C, and every hour after washing the fragments in order to remove the unbound antibody. No significant binding difference (expressed as per cent final activity in comparison with initial one) of the aspecific antibody between normal and atherosclerotic fragments was found. By contrast, TRF1 binding was significantly higher (p < 0.001) in atherosclerotic than in normal fragments (26.0 +/- 11.5% in atherosclerotic plaques, versus 9.23 +/- 9% in fatty streaks, versus 1.9 +/- 0.6% in normal endothelium.(ABSTRACT TRUNCATED AT 250 WORDS)

Immunological properties of a radioiodinated monoclonal antibody and its F(ab')2mu fragments directed against the polymorphic epithelial mucin of human breast cancer.

The purification of the IgM monoclonal antibody 436 against a breast tumor antigen from mouse ascitic fluid is reported. The purified immunoglobulin was radioiodinated and the resulting product assessed for its binding capacity and binding specificity. Purified IgM-436 served for F(ab')2 mu preparation which was tested for its antigen binding capacity. Radioiodinated IgM-436 and its F(ab')2 mu retained their immunological activity which was never lower than those of the corresponding cold products.

Anti D dimer monoclonal antibodies: a possible scintigraphic agent for immunodetection of thrombi.

The aim of this work was to produce a MoAb able to react with clots but not with fibrinogen. Monoclonal antibodies directed towards DD dimers, against specific products of plasmic digestion of cross-linked fibrin, were obtained. One of these antibodies, F 60/43/8, showed a 1.79 x 10(9) l mol-1 binding constant in spite of the presence of fibrinogen at a 4000 times greater concentration than the cross-linked fibrin. In vitro studies with 125I-F(ab')2 of F 60/43/8 showed that 34-80% of the radioactivity can be found in human clots, in the presence of physiologic concentrations of fibrinogen, and that 96-h washing does not remove the labelled F(ab')2 from the clot. 131I-F(ab')2 was injected into rabbits in which a clot had formed in an artery (six rabbits) or in a vein (six rabbits) of the left ear. Scintigraphic images of the clot were always obtained. In conclusion, the results of this work suggest that F 60/43/8 may be used as a specific antibody for the radioimmunodetection of thrombi.

Equilibrium radionuclide ventriculography in Duchenne's cardiomyopathy.

Rest and stress (handgrip) equilibrium radionuclide ventriculography was performed in 20 patients with Duchenne muscular dystrophy. The mean value of LVEF was normal, but two patients showed values below 35% and another two patients values over 70%. Mean regional wall motion values were less than 2 in lateral (posterior and inferior) and septal walls. Handgrip usually produced a reduction of LVEF and regional wall motion: in three cases severe decrease of motility was observed. Equilibrium ventriculography appears to be useful in the selection of patients with high functional cardiac involvement, integrating the characteristic ECG and echography, and, perhaps, in the assessment of myocardial tolerance to physical therapy.

Clinical evaluation of the 99mTc-diethyl-HIDA plasma clearance curve and observations on the third exponential term.

Blood clearance curves of 99mTc-HIDA have been evaluated in 18 healthy volunteers and 55 patients affected by chronic liver diseases. The slope (K) of the third exponential term of the blood clearance curve can be considered as an index of the 99mTc-diethyl-HIDA liver cell uptake; therefore, this parameter seems to be able to discriminate healthy volunteers from patients affected by hepatocellular dysfunction.

[Synergism of findings from scintiscanning and selective arteriography in hepatic pathology]. / Sul sinergismo di informazione tra scintigrafia ed arteriografia selettiva nella patologia epatica.

198Au scintiscanning and selective arteriography of the liver were combined in the examination of 50 patients. The results are discussed and the contribution made by each technique and by the combined examination to the establishment of a diagnosis is explained. Five cases are described in detail.