14-Cmethionine uptake as a potential marker of inflammatory processes after myocardial ischemia and reperfusion

A relationship between L-[methyl-11C]methionine (11C-methionine) uptake and angiogenesis has been suggested in gliomas. However, methionine uptake in myocardial ischemia and reperfusion has received little attention. We investigated the serial changes and mechanisms of 14-Cmethionine uptake in a rat model of myocardial ischemia and reperfusion. Methods: The left coronary artery was occluded for 30 min, followed by reperfusion for 1-28 d. At the time of the study, 14-Cmethionine (0.74 MBq) and 201Tl (14.8 MBq) were injected intravenously at 20 and 10 min before sacrifice, respectively. One minute before sacrifice, the left coronary artery was reoccluded, and 99mTc-hexakis-2-methoxyisobutylisonitrile (150-180 MBq) was injected to verify the area at risk. Histologic sections of the heart were immunohistochemically analyzed using anti-CD68, anti-smooth-muscle a-actin (SMA), and antitroponin I and compared with the autoradiography findings. Results: Both 14Cmethionine (uptake ratio, 0.71 ± 0.13) and 201Tl uptake were reduced in the area at risk at 1 d after reperfusion. However, 3 d after reperfusion, an increased 14-Cmethionine uptake (1.79 ± 0.23) was observed corresponding to the area of still-reduced 201Tl uptake, and the 14-Cmethionine uptake gradually declined until 28 d. The increased 14-Cmethionine uptake area at 3 and 7 d corresponded well to the macrophage infiltrations demonstrated by positive CD68 staining. Anti-SMA staining appeared at 7 d, after which CD68 staining was gradually replaced by the SMA staining, suggesting that methionine uptake in the early phase after ischemia and reperfusion might reflect inflammatory activity. Conclusion: 14-Cmethionine accumulated in the infarcted area, and its uptake corresponded closely to macrophage infiltration at 3-7 d after reperfusion. Methionine imaging may be useful for inflammatory imaging early after myocardial infarction. COPYRIGHT © 2013 by the Society of Nuclear Medicine and Molecular Imaging, Inc

Nipple-centered Radiate M PR Images of M DCT for Evaluation of Breast Cancer Extent ― Correlation with M ammography and Pathologic Specimen ―

Background & Aims : Evaluation of the extent of breast cancer lesions is important for selecting the appropriate surgical procedure or to determine the surgical margin. We aimed to assess the diagnostic accuracy of nipple-centered radiate multiplanar reconstruction (NRMPR)images using multidetector row helical computed tomography (MDCT), comparing it with conventional mammography. M ethods : Our subjects were 26 breast cancer patients with a total of 29 lesions who sequentially received contrastenhanced MDCT imaging for preoperative evaluation. We measured the maximum diameter of the breast cancer in the direction toward the nipple on NRMPR images and mammography. All data were correlated with histopathological mapping of the specimens. Results : The tumor extent measured on NRMPR images and in pathological examinations ranged from 12.4 to 66.0mm (average, 28.0mm) and 10 to 70mm (average, 27.9 mm), respectively. The correlation coefficient of the two measurements was 0.898. On mammography, two lesions were not clearly identified. The correlation coefficient of mammography and pathological measurements was 0.554. Conclusions : The addition of NRMPR images to mammography provides more information to evaluate breast cancer extension toward the nipple. Potentially, it provides a clue for selecting the appropriate surgical procedure or surgical resection margin for breast cancer