Objective To compare the efficiency of 18F-FDG PET/CT and contrast enhanced ultrasound (CEUS) in detection of HCC recurrence after surgery or radiofrequency ablation (RFA).Methods Twenty-seven HCC patients (22 males,5 females; average age:47 years) were included in this study,of which 15 patients underwent surgery and 12 patients underwent RFA therapy.18F-FDG PET/CT and CEUS were performed within 2 weeks in all patients to detect recurrence.Final diagnosis was made by pathology or clinical follow-up (＞6 months),and the sensitivity,specificity and accuracy of 18F-FDG PET/CT and CEUS were calculated and compared.McNemar test was used for data analysis.Results Twenty-five patients were diagnosed with HCC recurrence,including 11 cases with extrahepatic metastases.Another 2 patients had extrahepatic metastases without HCC recurrences.The sensitivity,specificity and accuracy in detection of liver lesion with 18F-FDG PET/CT were 92.0％ (23/25),2/2 and 92.6％ (25/27),respectively.While with CEUS,the corresponding values were 60.0％ (15/25),2/2 and 63.0％ (17/27),respectively.In CEUS positive group,the sensitivity and accuracy were 100％(15/15) for both methods.In CEUS negative group,the sensitivity,specificity and accuracy of 18 F-FDG PET/CT in detection of liver lesion were 8/10,2/2 and 83.3％(10/12),respectively.The sensitivity and accuracy of 18F-FDG PET/CT were significantly higher than those of CEUS (0,16.7％(2/12) ; x2 =5.373,5.250,both P＜0.05).Moreover,the sensitivity of 18 F-FDG PET/CT in detecting extrahepatic metastasis was 100％ (13/13).Conclusions 18 F-FDG PET/CT is more sensitive and accurate than CEUS (especially in CEUS negative cases) in detecting recurrence of HCC after surgery or RFA.18F-FDG PET/CT also could be useful for detection of extrahepatic metastasis.

Objective To study the determination of biological activity of ?_1-AT with chromogenic substrate and its influential factors using fresh pooled normal human plasma as reference standard.Methods Measuring absorption value of reactions between residual trypsin and BAPNA at 405nm,after ?1-AT inhibition by excess trypsin.Fresh pooled normal human plasma was used as reference standard to calculate the biological activity of?1-antitrypsin.Results Good linear correlation was obtained when the plasma was diluted to 1/50 to 1/100.PEG4000,sucrose,S/D(Tween80/TNBP) and sodium caprylate did not influence the biological activity of ?1-AT,but?1-AT activity was increased by about 20% when the concentration of sodium citrate was above 0.125mol/L.Conclusion The experiment proved that?1-AT biological activity was determined using fresh pooled human plasma as reference standard,the method is stable and reliable.Except sodium citrate,all of the materials used in the assay did not influence the determination of?1-AT activity.

Objective To investigate the usefulness of 13N-NH3 PET in detecting brain lesions which show hypometabolism on 18F-FDG PET.Methods 13N-NH3 PET imaging was performed for a prospective study in 18 patients with brain lesions that showed hypometabolism compared with normal brain tissue on 18F-FDG PET scans.Fourteen patients underwent 18 F-FDG PET imaging for initial diagnosis and 4 patients for detection of astrocytoma recurrence (13 males,5 females,age 20-68 (42.4 ± 12.6) years).Ten gliomas,1 metastatic tumor,1 dysembryoplastic neuroepithelial tumor (DNT) and 6 non-neoplastic lesions (including 3 cases of radiation necrosis,2 cases of encephalitic foci,and 1 case of ischemic lesion)were verified by histopathological examination (n =13) or clinical follow-up (n =5).The tumor-to-contralateral brain tissue ratios (T/C) were calculated by the ROI method.The diagnostic efficacy of 13N-NH3 PET was evaluated.Paired t test and two-sample t test were performed to analyze the differences of T/C between different groups.Results Seven (5 astrocytomas and 2 glioblastomas) of 12 brain tumors (sensitivity:58％,7/12) showed increased 13N-NH3 uptake (higher uptake than the contralateral brain tissue),while 3 low-grade gliomas,1 metastatic tumor,and 1 DNT showed decreased 13N-NH3 uptake (no uptake or lower uptake than the contralateral brain tissue).The uptake ratio of 13N-NH3 was significantly higher than that of 18 F-FDG (1.24 ± 0.66 vs 0.67 ± 0.24,t =-3.740,P ＜ 0.05) in the tumors.All six non-neoplastic lesions showed decreased 13N-NH3 uptake (specificity:6/6).The T/C ratios of 18F-FDG and 13N-NH3 in the non-neoplastic lesions were 0.68 ±0.15 and 0.70 ±0.19,respectively,and there was no significant difference between them (t =-0.246,P ＞ 0.05).The T/C ratio of 13N-NH3 in the tumors was significantly higher than that in the non-neoplastic lesions (1.24 ± 0.53 vs 0.70 ± 0.19,t =2.624,P ＜ 0.05).Conclusion 13N-NH3 PET imaging may be helpful to detect and differentiate brain tumors with hypometabolism as detected by 18 F-FDG PET imaging from non-neoplastic lesions with high specificity,especially for cerebral astrocytomas,but the sensitivity is relatively limited.

Objective To investigate the characteristics of regional cerebral glucose metabolism in patients with fatal familial insomnia(FFI) using 18F-fluorodeoxyglucose(18F-FDG) PET. Methods Patient 1 with symptoms for 2 months and patient 2 with symptoms for 6 months were studied by brain 18 F-FDG PET.Compared with 20 normal controls, the data were analyzed by visual analysis at first, and then each patient was compared with age-matched normal controls using statistical parametric mapping( SPM ). Results As compared with 10 normal controls, metabolic changes in patient 1 was characterized by hypometabolism in thalamus, parietal cortices, caudate nucleus, pre-frontal cortices and posterior cingulate gyrus ( t ＞ 2. 82,P ＜0. 01 ). In patient 2, these changes were more obvious (t ＞ 2. 82, P ＜ 0. 01 ) with metabolic decrease also shown in temporal and occipital cortices ( t ＞ 2. 82, P ＜ 0. 01 ). Conclusion In FFI patients, brain metabolism changes are mainly manifested as hypometabolism in thalamus and cerebral cortex. The metabolic changes in cerebral cortex will be more widely spread with the development of FFI. 18F-FDG PET imaging was a valuable method to evaluate patients with FFI.

Objective To explore the value of 18F-FDG PET/CT in predicting tumor recurrence for hepatocellular carcinoma (HCC) after liver transplantation (LT).Method We respectively analyzed 52 patients with HCC who underwent the 18F-FDG PET/CT examination before LT.In terms of tumor recurrence,all patients were divided into recurrence group and non-recurrence group.According to the degree of 18F-FDG uptake,all patients were divided into PET(-) group and PET (+) group.The SUVmax of primary tumor/the SUVmax of normal-liver background (T/B) was calculated by 18F FDG PET/CT.All patients were then divided into T/B≤1.15 group and T/B＞1.15 group.Result During the follow-up period,25 out of 52 patients (48.1％) developed posttransplant HCC recurrence and 27 (51.9％) had no recurrence.T/B of patients with recurrence (2.51 ± 0.95) was significantly higher than that of patients with non-recurrence (1.37 ± 0.46),t =4.12,P＜0.001.The disease-free survival rate of 0.5 year,1 year,2 years and 3 years after LT in PET(-) group and PET(+) group was 100.0％,92.3％,92.3％ and 92.3％,and 89.7％,59.0％,43.6％ and 35.7％ respectively.Log-rank test revealed that disease-free survival rate in PET(-) group was significantly higher than that in PET(+) group,x2 =17.8,P=0.003.The disease-free survival rate of 0.5 year,1 year,2 years and 3 years after LT in T/B≤1.15 group and T/B＞1.15 group was 100.0％,92.3％,92.3％ and 92.3％,and 89.5％,59.7％,42.1％ and 33.7％ respectively.Log-rank test showed that disease-free survival rate of T/B≤1.15 group was significantly higher than that of T/B＞1.15 group,x2 =10.24,P =0.001.Conclusion 18F-FDG PET/CT can predict HCC recurrence after LT.PET(-)and T/B≤1.15 of the 18F-FDG PET/CT in patients with HCC after LT were associated with a good prognosis,and PET(+) and T/B＞1.15 of the 18F-FDG PET/CT in patients with HCC after LT with a poor prognosis.

Dynamic ~(13)N-NH_3 positron emission tomography (PET) imaging was performed in 8 normal subjects and 6 cases of hypopituitarism. The pituitary images were small and delayed, and blood perfusion and radioactive uptake were decreased in hypopituitarism. ~(13)N-NH_3 PET imaging shows diagnostic value in hypopituitarism.

Objective To investigate the clinical,laboratory,and neuroimaging characteristics of neuroacanthocytosis.Methods Eight patients with neuroacanthocytosis were retrospectively analysed.Acanthocytes were tested by peripheral blood smear,wet preparation with saline dilution,and scanning electron microscope.Results Two male and 6 female patients were included.The age at onset was between 10 and 35 years,with a mean age at onset of 22 years.Four patients firstly presented with oral-facial-lingual dystonia,3 patients firstly presented with involuntary movements of the distal limbs and experienced the oral facial dystonia during the course of disease,and 1 patient primary presented with a parkinsonian syndrome.Four patients had generalized tonic-clonic seizures were reported in 4 patients,and 4 patients had cognitive impairment.Hypotonia and hyporeflexia were reported in 6 patients.The peripheral blood smear revealed the presence of acanthocytes in 7 patients,in addition,wet preparation with saline dilution and scanning electron microscope revealed the presence of acanthocytes in the remaining one.All patients showed slightly elevated serum creatine kinase.Brain magnetic resonance imaging (MRI) showed variable atrophy of the bilateral caudate nuclei and putamen,with or without a rim of increased T2-intensity in 6 patients,but the films of 2 patients were read as normal.Electromyography and nerve conduction velocity were examined in 4 patients.The results indicated axonal damage in 2 patients,and were normal in the other 2 patients.Acanthocytosis was confirmed by peripheral blood smear in 7 cases,by wet preparation with saline dilution in 8 cases and by scanning electron microscope in 2 cases.Conclusions Neuroacanthocytosis is a progress neurodegenerative disorder mainly affected the basal ganglia. The clinical characteristics include oral facial dystonia,limbs chorea,cognitive impairment,and seizures. Brain MRI showed variable atrophy of the bilateral caudate nuclei and putamen.The peripheral blood smear,wet preparation with saline dilution,and scanning electron microscope methods of peripheral blood examination are critical in the diagnosis of neuroacanthocytosis.

OBJECTIVETo assess the correlation of primary colorectal cancer (CRC) lesions' maximum standardized uptake value (SUVmax) and tumor to normal tissue SUVmax ratio (T/N ratio) detected by ¹⁸F-deoxyglucose positron emission computed tomography (¹⁸F-FDG PET-CT) imaging with the postoperative prognosis.

METHODSClinicopathological data of 92 CRC patients who underwent curative resection after the PET-CT examination and received ¹⁸F-FDG PET-CT examination from January 2009 to December 2013 in the First Affiliated Hospital of Sun Yat-sen University were reviewed retrospectively. The correlation of SUVmax and T/N ratio in primary lesions with clinicopathological factors was analyzed. The optimal cutoff point of disease-free survival time of SUVmax, T/N ratio and the maximum tumor diameter were investigated by using ROC curve analysis. Association of clinicopathological factors and prognosis was examined and the Cox proportional hazard regression model was used in the multivariate analysis.

RESULTSPrimary SUVmax was associated with tumor TNM staging, location, differentiation degree and the maximum tumor diameter, while T/N ratio was only associated with pathological type (all P<0.05). The optimal cutoff point of disease-free survival time of SUVmax, T/N ratio and the maximum tumor diameter were 12.2 (sensitivity 67.6%, specificity 63.6% ), 6.9 (sensitivity 51.4%, specificity 74.5%) and 4.3 cm (sensitivity 56.8%, specificity 80.0%) respectively. Univariate analysis showed that age, TNM staging, tumor location, differentiation degree, the maximum tumor diameter, T/N ratio and CA125 level were significant predictors of survival. Multivariate analysis demonstrated that TNM staging (P=0.000, OR=3.98, 95% CI:2.12-7.45), tumor location (P=0.009, OR=0.43, 95% CI:0.23-0.81), tumor differentiation degree (P=0.001, OR=7.52, 95% CI:2.12-25.9) and T/N ratio (P=0.008, OR=2.92, 95% CI:1.33-6.411) were independent predictors of survival. However, SUVmax was not independent predictor of disease-free survival.

CONCLUSIONFor postoperative prognosis of colorectal cancer patients, T/N ratio is more valuable than the of primary tumor SUVmax.

Colorectal Neoplasms ; Disease-Free Survival ; Fluorodeoxyglucose F18 ; Humans ; Multimodal Imaging ; Neoplasm Staging ; Positron-Emission Tomography ; Postoperative Period ; Prognosis ; Proportional Hazards Models ; ROC Curve ; Retrospective Studies ; Tomography, X-Ray Computed

ObjectiveTo evaluate the technique and implications of No.12 lymph node dissection for advanced gastric cancer with D2 lymphadenectomy.MethodsIn this study 102 advanced gastric cancer patients undergoing D2 lymphadenectomy from January 2010 to January 2011were retrospectively analysed. ResultsThe average number of No.12 lymph node dissected was 4.3.The metastatic rate of No.12 lymph node was 21.6％.Postoperative pancreatic fistula developed in 4 cases,and lymphatic fistula in 6.There was no anastomotic leakage,lymphatic duct leakage,biliary leakage,post-operative jaundice and bleeding.ConclusionsNo.12 lymph node dissection for advanced gastric cancer is safe and necessary.

Objective To investigate the clinical value of [11C]CFT PET in the diagnosis and severity assessment of Parkinson disease (PD). Methods Thirty-eight patients with PD at various Hoehn & Yahr (H&Y) stages were included and underwent a [11C]CFT PET scan. The correlation between [11C]CFT uptake and unified Parkinson disease rating scale part III (UPDRS III) of PD patients was evaluated by calculating Pearson’s regression coefficient. Statistical parametric mapping (SPM) analysis was performed to compare the difference of dopamine transporter (DAT) distribution between ear-ly and advanced PD patients. Results There was a significant reduction of [11C]CFT uptake in the bilateral striatum of PD patients. There was a significant negative correlation between clinical scores of UPDRS III, rigidity, bradykinesia, pos-ture, gait and [11C]CFT uptake in the striatum. The SPM analysis revealed a significant and asymmetric decrease of [11C] CFT uptake in the striatum, predominantly on the putamen and caudate nucleus contralateral to the onset limb, in the posterior area of ipsilateral putamen in early PD (H&Y 1-2) patients compared with the normal controls. There was a sig-nificant symmetric decrease of [11C]CFT uptake in both putamen and caudate nucleus in advanced PD (H&Y 3-5) pa- tients, compared with normal controls. Compared with early PD patients, the reduction of DAT was more severe in bilater-al caudate nucleus and the ipsilateral putamen in the advanced PD patients. Conclusions [11C]CFT PET is a sensitive biomarker in the diagnosis and assessment of disease severity of PD patients.