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Diagnosis of fetal growth restriction (FGR) entails difficulties with differentiating fetuses not fulfilling their growth potential because of pathologic conditions, such as placental insufficiency, from constitutionally small fetuses. The feasibility of placental MRI for risk stratification among pregnancies diagnosed with FGR remains unexplored.To explore quantitative MRI features useful to identify pregnancies with unfavorable outcomes and to assess the diagnostic performance of visual analysis of MRI to detect pregnancies with unfavorable outcomes, among pregnancies diagnosed with FGR.Retrospective.Thirteen pregnancies with unfavorable outcomes (preterm emergency cesarean section or intrauterine fetal death) and 11 pregnancies with favorable outcomes performed MRI at gestational weeks 21-36.A 5-T, half-Fourier-acquired single-shot turbo spin echo (HASTE), spin-echo echo-planar imaging (SE-EPI) and T2 map derived from SE-EPI.Placental size on HASTE sequences and T2 mapping-based histogram features were extracted. Three radiologists qualitatively evaluated the visibility of maternal cotyledon on HASTE and SE-EPI sequences with echo times (TEs) = 60, 90, and 120 msec using 3-point Likert scales: 0, absent; 1, equivocal; and 2, present.Welch's t-test or Mann-Whitney U test for quantitative features between the favorable and unfavorable outcome groups. Areas under the receiver operating curves (AUCs) of the three readers' visual analyses to detect pregnancies with unfavorable outcomes. A P value of0.05 was inferred as statistically significant.Placental size (major and minor axis, estimated area of placental bed, and volume of placenta) and T2 mapping-based histogram features (mean, skewness, and kurtosis) were statistically significantly different between the two groups. Visual analysis of HASTE and SE-EPI with TE = 60 msec showed AUCs of 0.80-0.86 to detect pregnancies with unfavorable outcomes.Placental size, histogram features, and visual analysis of placental MRI may allow for risk stratification regarding outcomes among pregnancies diagnosed with FGR.3 TECHNICAL EFFICACY: Stage 5.

Background Neuromelanin‐sensitive magnetic resonance imaging techniques have been developed but currently require relatively long scan times. The aim of this study was to assess the ability of black‐blood delay alternating with nutation for tailored excitation‐prepared T1‐weighted variable flip angle turbo spin echo (DANTE T1‐SPACE), which provides relatively high resolution with a short scan time, to visualize neuromelanin in the substantia nigra pars compacta (SNpc). Methods Participants comprised 49 healthy controls and 25 patients with Parkinson's disease (PD). Contrast ratios of SNpc and hyperintense SNpc areas, which show pixels brighter than thresholds, were assessed between DANTE T1‐SPACE and T1‐SPACE in healthy controls. To evaluate the diagnostic ability of DANTE T1‐SPACE, the contrast ratios and hyperintense areas were compared between healthy and PD groups, and receiver operating characteristic analyses were performed. We also compared areas under the curve (AUCs) between DANTE T1‐SPACE and the previously reported gradient echo neuromelanin (GRE‐NM) imaging. Each analysis was performed using original images in native space and images transformed into Montreal Neurological Institute space. Values of P, April Infographic: Neuromelanin‐Sensitive Magnetic Resonance Imaging Using DANTE Pulse

Introduction Simultaneous liver and kidney transplantation is a life-saving procedure for patients with liver failure and irreversible renal dysfunction. However, some studies have reported the recovery of native renal function after simultaneous liver and kidney transplantation. Case presentation A 33-year-old woman initially underwent living-donor liver transplantation for liver failure. When graft liver failure developed, she also sustained acute renal failure and required continuous hemodiafiltration for 6 weeks. Simultaneous liver and kidney transplantation from a brain-dead donor recovered her liver and renal function. A 1-year protocol graft kidney biopsy revealed acute cellular rejection despite stable serum creatinine levels. Renal scintigraphy showed functional native kidneys masking acute rejection of the graft kidney. The rejection was improved by pulse steroid therapy. Conclusion Acute rejection of the graft kidney may silently progress due to recovery of the native kidney function after simultaneous liver and kidney transplantation. Renal scintigraphy and graft kidney biopsy should be considered even if blood tests indicate stable total renal function.

Background Although 18 F-FDG-PET/CT is a widely used diagnostic tool for several malignancies, its efficacy in diagnosing pancreatic neuroendocrine tumors is reported to be controversial because of the short-term follow-up. Methods We retrospectively compared demographics and pathological features between 18 F-FDG-positive and -negative diseases. Additionally, we evaluated whether the avidity of 18 F-FDG-PET/CT affected earlier recurrence after curative treatment of non-functioning tumors. The median duration of observation was 65.6 months. Results Seventy-two patients were enrolled. 18 F-FDG-positive diseases were pathologically advanced and significantly associated with metastatic behavior. In a multivariate analysis, metastatic behavior and WHO tumor grade was independently associated with 18 F-FDG accumulation. Only 25% of functional tumors (4/16) and 8% of insulinomas (1/12) were 18 F-FDG-positive. In a Kaplan-Meier analysis in patients with non-functioning tumors (n = 56), 18 F-FDG-positivity was significantly correlated with poorer recurrence-free survival (RFS) but had no correlation with overall survival. In univariate analysis of factors associated with shorter RFS, male gender, prevalence of nodal metastasis, WHO tumor grade ≥G2, or 18 F-FDG-positive disease were significantly higher in patients with shorter RFS, whereas only 18 F-FDG-positivity was associated with shorter RFS in multivariate analyses. Conclusions The avidity of 18 F-FDG-PET/CT was associated with metastatic behavior of pancreatic neuroendocrine tumors and recurrence after treatment of non-functioning tumors.

This first-in-man study was carried out to evaluate the safety, whole-body distribution, dose estimation, and lesion accumulation of 18 F-FSU-880, a newly developed probe targeting prostate-specific membrane antigen. Six prostate cancer patients with known metastatic lesions underwent serial whole-body PET/computed tomography (CT) with 18 F-FSU-880. Blood and urine were analyzed before and after PET/CT. Accumulation of 18 F-FSU-880 in organs and metastatic lesions in serial PET images were evaluated by measuring the standardized uptake values. From the biodistribution data, the organ doses and whole-body effective dose were calculated using OLINDA/EXM software was developed by Dr. Michael Stabin of Vanderbilt University, Nashville, Tennessee, USA. 18 F-FSU-880 PET/CT could be carried out without significant adverse effects. High physiological uptake was observed in the salivary/lachrymal glands and kidneys. The effective dose was calculated to be 0.921 × 10-2 mSv/MBq. Known metastatic lesions were clearly visualized with high image contrast that increased with time, except in 1 patient, whose bone metastases were well-controlled and inactive. The PET/CT with 18 F-FSU-880 could be carried out safely and could clearly visualize active metastatic lesions. The present results warrant further clinical studies with a larger number of cases to verify the clinical utility of 18 F-FSU-880 PET/CT in the management of prostate cancer patients.

Functioning pancreaticoduodenal neuroendocrine tumors (PD-NETs) are popular in a textbook, but they are still unfamiliar to a general clinician, and delay of diagnosis or misdiagnosis has been reported even today. It is a consensus that sporadic functioning PD-NET is cured only by surgical resection. So, early detection and early resection is the gold standard for the treatment of functioning PD-NET. Functioning PD-NETs in patients with multiple endocrine neoplasia type 1 (MEN 1) are often multiple. You should check about MEN 1 whenever you encountered multiple PD-NET. They are diagnosed in younger age than sporadic cases. In most cases they are accompanied with numerous microscopic or macroscopic nonfunctioning P-NETs, which are potentially metastatic and the most common cause of death in MEN 1 patients. © Japanese Society of Hepato-Biliary-Pancreatic Surgery

Although yolk sac tumors (YSTs) are the second most common malignant germ cell tumor of the ovary, those arising from the omentum or pelvic peritoneum are extremely rare and have no established treatment guidelines. We report a case of a primary YST disseminated throughout the abdomen and associated with a high serum alpha-fetoprotein (AFP) elevation (441 611 ng/ml). Optimal cytoreduction was not achieved in order to preserve the patient's fertility and avoid adjacent organ injury. Residual tumor responded to adjuvant chemotherapy with a sharp decline in AFP levels, and confirmed remission was documented by serial (18)F-fluorodexyglucose-positoron emission tomography and computerized tomography (FDG-PET/CT). In cases of advanced YST with unresectable residual disease, AFP levels combined with FDG-PET/CT scans may be a helpful way to monitor treatment response and assist in treatment planning for a disease that primarily affects young women who may desire to preserve fertility.

Purpose To demonstrate the feasibility of diffusion tensor imaging (DTI) of kidneys with respiratory triggering, and determine the optimal imaging parameters for fraction anisotropy (FA) maps. Materials and Methods DTI of kidneys from 16 healthy volunteers was performed using a 1.5T scanner. Five different sequences with different parameters including respiration-triggered acquisition or multiple breath-holding, slice thicknesses of 3 or 5 mm, and different numbers of signal averaging and b values were compared. FA and apparent diffusion coefficients (ADCs) of the cortex and medulla were measured. Measurement error within the same and repeated examination was examined using within-individual standard deviation (Sw). Results FAs of the renal cortex were lower than the medulla (mean value of a sequence ranging 0.148–0.224, 0.433–0.476) and the ADCs of the cortex were higher than the medulla (2.26–2.69 × 10−3 mm2/s, 1.77–2.19 × 10−3 mm2/s) in all sequences (P < 0.001). The renal cortex–medulla difference was the largest, with respiratory trigger- ing including a 3-mm slice thickness, three signal averages,and a b-value = 0, 200, or 400 s/mm2 (P < 0.001). Sw tended to be smaller in the sequence with a b-value of 400 s/mm2. Conclusion DTI of kidneys with respiratory triggering is feasible with excellent cortex–medulla differentiation. J. Magn. Reson. Imaging 2009;29:736–744. © 2009 Wiley-Liss, Inc.

Myelotoxicity is the main factor which decides the maximum tolerated dose (MTD) in radioimmunotherapy (RIT). Since bone marrow is mostly irradiated from blood radioactivity, enhancing the clearance of unbound circulating radiolabeled antibody is important to reduce myelotoxicity and to increase the MTD. We applied the avidin chase method, which was devised to obtain high tumor-to-background ratios in tumor-targeting, to RIT of experimental liver micrometastases and evaluated its influence on the side effects and therapeutic outcome. Seven days after intrasplenic injection of human colon cancer LS174T cells, nude mice were intravenously injected with biotinylated (131)I-labeled anti-CEA monoclonal antibody (MAb) (24 - 38 microg, 11.1 MBq). Mice of the chase group then received an intravenous injection of avidin twice (24 and 30 h, 72 - 115 microg each). Biodistribution, side effects (white blood cell counts and body weight change), and short- and long-term therapeutic effects were determined. Avidin chase markedly accelerated the clearance of radiolabeled MAb from the blood (P0.0001) and normal tissues, resulting in milder leukocytopenia and body weight loss, both of which recovered earlier than in the non-chase group (P0.01). The tumor uptake of radiolabeled MAb was also decreased by avidin chase, but the metastases-to-background ratios were increased. Avidin chase gave the therapeutic gain ratio of 1.89. Treated groups with and without avidin chase showed significant therapeutic effects compared to the non-treated group. There was no significant difference in the therapeutic effects between the two treated groups. Avidin chase effectively reduced the side effects of RIT and should increase the MTD.

BACKGROUND Positron emission tomography (PET) using 18F-fluoro-2-deoxy-D-glucose (FDG) has been used for the evaluation of various tumors, but accumulation in inflammatory lesions makes it a controversial modality. The aim of this study was to investigate the usefulness of delayed scanning in differentiation between malignant and benign lesions in the pancreas. METHODS Forty-seven patients with suspected pancreatic carcinoma were studied by FDG-PET. All patients received approximately 370 megabequerels of FDG after a transmission scan, and an emission scan was performed 1 hour and 2 hours later for all patients. A subset of 19 patients was also scanned at 3 hours postinjection. The standardized uptake value (SUV) was determined, and the retention index was calculated by dividing the increase in the SUV between 1 hour and 2 hours postinjection by the SUV at 1 hour postinjection. RESULTS Of 27 malignant lesions, the SUVs of 22 lesions increased at 2 hours postinjection, whereas the FDG uptake in 17 of 20 benign lesions decreased. The SUVs at 3 hours postinjection were higher than those at 2 hours postinjection in 9 of 14 malignant lesions and in 2 of 5 benign lesions. Malignant lesions showed a higher retention index than benign lesions (mean ± standard deviation: 12.36 ± 13.37 and −7.05 ± 17.28, respectively; P < 0.0001). Applying an SUV of 2.5 at 1 hour postinjection with the cut-off value for the differentiation between malignant and benign lesions caused one false negative result and seven false positive results, with a diagnostic accuracy of 83.0% (39 of 47 patients). However, combining the retention index with the SUV obtained at 2 hours postinjection provided a higher diagnostic accuracy (91.5%; 43 or 47 patients) than the SUV alone. The false negative rate remained constant when the retention index was taken into account. Images at 3 hours postinjection usually were unhelpful in differentiating further between malignant lesions and benign lesions. CONCLUSIONS The current data suggest that delayed FDG-PET scanning at 2 hours postinjection may contribute to differentiation between malignant and benign lesions in the pancreas. Cancer 2000;89:2547–54. © 2000 American Cancer Society.

Adhesion molecules play a major role in the processes of invasion and metastasis of malignant tumors. Their expression within tumors has been reported to be quantitatively and qualitatively altered according to the invasiveness and metastatic potential of the tumor. The present study tested whether the intratumoral expression of integrin alpha 3 can be detected by a radiolabeled monoclonal antibody. The in vitro binding study with four different human cancer cells showed that radioiodinated GA17 antibody recognizing integrin alpha 3 bound specifically to these cells to varying degrees, according to the antigen density on each cell. The biodistribution study with 125I- and 111In-labeled antibodies showed specific localization of radiolabeled GA17 to the xenografts. However, the in vivo tumor localization was not proportional to the antigen density calculated in vitro, and antibody metabolism varied among the tumors, as was also confirmed by in vitro radionuclide retention assay. The intratumoral distribution of radioactivities varied reflecting the antigen expression within the tumor. These results indicate that 1) integrin alpha 3 was expressed in various kinds of tumors and could be localized by the radiolabeled antibody, and 2) the expression of integrin alpha 3 and the metabolism of the radiolabeled antibody after binding to the antigen within the tumor were variable among the tumors, which affected the radionuclide distribution characteristics. The expression of adhesion molecules within these tumors was noninvasively detected by a radiolabeled antibody. It may be possible to use integrin alpha 3, when it is overexpressed, as a target of therapy with antibodies radiolabeled with alpha or beta emitters.

Although development of human anti-murine immunoglobulin antibody (HAMA) is often seen in patients receiving murine antibodies, the variety of methods used for detecting HAMA makes it difficult to compare directly the HAMA responses measured by different assays. In the present study, several parameters of the HAMA response to two murine monoclonal antibodies were evaluated. The anti-sialosyl Tn antibody MLS102 and anti-CA125 antibody 145-9, which were labeled with 111In, were injected intravenously into 17 colorectal cancer patients and 11 ovarian cancer patients for immunoscintigraphy, respectively. HAMA was measured by enzyme-linked immunosorbent assay. There was no difference in baseline HAMA levels before antibody injection between the two groups. HAMA developed more frequently in ovarian cancer patients receiving the 145-9 antibody than in colorectal cancer patients receiving the MLS102 antibody (9/11 vs. 6/17, P < 0.05). No significant difference was observed in maximal HAMA levels between the two groups of patients. However, time to reach the maximal levels was delayed and the duration of the response seemed longer in ovarian cancer patients. Among 11 patients receiving the 145-9 antibody three patients became positive for HAMA more than 2 months after antibody injection and the other two had HAMA activity in their sera for more than 17 months. HAMA response was different between the two antibodies, and late onset or long duration of HAMA response against the 145-9 antibody suggests the importance of HAMA measurement in patients who receive a second injection of murine antibodies even after a long interval.