The off-label use of bevacizumab labeled with 99mTc as a new radiopharmaceutical for imaging of endometriosis is a promising noninvasive, new clinical procedure. The bevacizumab in monoclonal antibodies targeted at vascular endothelial growth factor (VEGF) is superexpressed in cases of endometriosis. In this study we evaluate the imaging of endometriosis lesion in rats (induced to endometriosis) using bevacizumab-99mTc. The results showed that bevacizumab-99mTc imaged the lesion and support his use for Nuclear Medicine applied to gynecology. Also the results appointed that this radiopharmaceutical has a hepatobiliary excretion. It is important to notice that the dose used was almost 0,01% of the usual dose for the bevacizumab.

No abstract

The data showed preservation of lymphatic drainage and visible sentinel lymph nodes even after transaxillary breast augmentation. Therefore, the authors believe that this procedure does not alter the integrity of mammary drainage for properly selected patients. These data provide surgeons with a less invasive treatment option for patients with early breast cancer, even when they have undergone prior breast augmentation through a transaxillary approach.

No abstract

Given discrepancies between methods for diagnosing hyposplenism, the purpose of this study was to evaluate the effect of the spleen size on the correlation between the methods, and to propose a model for improving the interpretation. Patients with renal allografts were included, in whom the spleen was assessed using Doppler ultrasound, scintiscan, and the presence of Howell-Jolly bodies (HJBs) in peripheral smears. In 35 subjects, scintiscan and HJBs were normal (Group 0); 20 had an abnormal result in both methods (Group 1); 34 had discordant results with HJBs present (Group 2); and 14 had discordant results with decreased spleen uptake (Group 3). There was no association between HJBs and scintiscan. The patients of Groups 1 and 2 had smaller spleens. The patients with smaller spleen had more hematological evidence of hyposplenism and exhibit smaller discrepancies between the methods than patients with larger spleen. The spleen can tip the balance from a normal to impaired function provided that the spleen size is below the critical mass required to maintain splenic function. A mild impairment of phagocytic function and slight dyserythropoiesis along with a small spleen would result in decreased take up of radiocolloid or the appearance of HJBs in blood smears.

No abstract

Objective: The purpose of this study was to compare renal transplant recipients healthy controls, in order to find scintigraphic signs of hyposplenism or hypersplenism by using qualitative and quantitative liver-spleen scan parameters. Material and Methods: Scanning parameters were evaluated in 88 renal transplant recipients and 59 controls after administration of 5-mCi of 99mTc-stannous colloid. Spleen uptake was characterized as normal, low, or high in comparison to the liver and bone marrow pattern uptake was described as normal or high.  The images were drawn over the liver and spleen for counting scintillations and measuring the area. Spleen/liver ratio from controls was correlated with qualitative spleen uptake of renal transplant recipients. Immunosuppressive regimens consisted of combinations of azathioprine or mycophenolate mofetil and rapamycin, tacrolimus or cyclosporine. Results: renal transplant recipients took up more radiocolloid and had larger livers and spleens than controls. Cases of lower (hyposplenism) and higher (hypersplenism) uptake in the spleen were more frequent in renal transplant recipients than in controls. There was a good correlation between spleen uptake of renal transplant recipients and spleen/liver ratio of controls. Discussion: renal transplant recipients liver and spleen took up more radiocolloid consistent with their enlarged state, likely due to activation of the mononuclear phagocyte system, probably by repeated exposure to infection. Low and high splenic uptake were found in renal transplant recipients, these findings are consistent with diagnosis of hyposplenism and hypersplenism respectively. Quantitative methods validated visual assessment.

The determination of the radiopharmaceutical binding on blood constituents is worthwhile to understand the biodistribution and to dosimetric considerations. We studied this binding of the Tc‐99m methylenediphosphonic acid (99mTc‐MDP) used to bone evaluation. This radiopharmaceutical was administrated in Wistar rats and after 5 min, blood was withdrawn with anticoagulant. The samples were centrifuged, plasma (P) and blood cells (BC) separated, precipitated with trichloroacetic acid (TCA) or ammoniun sulfate (AS) in various concentrations (0.1, 0.5, 1.0, 5.0, 10 and 20%) and soluble (SF) and insoluble fractions (IF) isolated. The percent of radioactivity (% ATI) in the fractions was determined. The % ATI on P was 84.58 ± 8.16 and on BC was 15.39 ± 8.17. Concerning to TCA, (i) the highest % ATI in IF‐P was from (40.64 ± 9.81) to the 5.0% TCA concentrations and (ii) on IF‐BC, % ATI decreased significantly (p<0.01) from (78.08 ± 7.58 to 66.98 ± 8.40) with the used TCA concentrations. The % ATI, when AS was used on (a) IF‐P was not modified by the AS concentrations, and (b) on IF‐BC varied from 77.46 ± 3.47 to 38.03 ± 8.76 respectively with the AS concentrations from 0.1. to 10.0%. We can speculate that the binding of the studied radiopharmaceutical to blood elements and the precipitation effect may depend on the chemical characteristics of the radiopharmaceutical studied and the mechanisms involved in its fixation on the blood elements.