ObjectiveTo investigate the effect of different reference vessel groups on CT perfusion in patients with nasopharyngeal carcinoma (NPC) after radiation therapy,and explore the feasibility of substitution of reference vessel.MethodsThirty patients with NPC after radiation therapy were divide into two groups,recurrence group ( n =19) and fibrosis group ( n =11 ).All patients underwent CT perfusion scans,and the CT parameters were calculated with different arterial input and vein output in order to study their differences.The vessels were internal carotid artery-internal jugular vein( ICA-IJV group),external carotid artery-retomandibular vein (ECA-RTV group)and external carotid artery-internal jugular vein( ECAIJV group) respectively.The differences of the CT parameters between local recurrence group and fibrosis group were compared among the various vessel groups by rank sum test.With the help of receiver operating characteristic curve (ROC),the diagnostic efficiencies were compared by the area under the ROC curve (AUC).ResultsIn ICA-IJV group,ECA-RTV group and ECA-IJV group,bloood flow(BF) of local recurrence group were 201.88,439.59,252.23 ml · min-1 · 100 g-1,while BF of fibrosis group were 98.96,180.50,106.55 ml · min-1 · 100 g-1.Blood volume (BV) of local recurrence group were 6.71,12.39,6.70 ml/l00 g,while BV of fibrosis group were 2.35,4.76,2.95 ml/100 g.Mean transit time (MTT) of local recurrence group were 1.66,1.50,1.56 s,while MTT of fibrosis group were 2.13,1.96,1.79 s.Permeability surface (PS) of local recurrence group were 19.31,36.39,15.22 ml · min- 1 ·100 g-1,while they were 16.58,29.08 ,16.63 ml · min-1 · 100 g-1 in the fibrosis group.The differencesof BF and BV between the local recurrence group and fibrosis group were statistically significant in each vessel group (P ＜ 0.05 ) but MTT and PS showed no significant difference( P ＞ 0.05 ).In ICA-IJV group,the AUC of BF,BV,MTT,PS were 0.909,0.947,0.677,0.703,respectively.BF,BV,MTT,PS in ECA-RTV group were 0.938,0.967,0.648,0.679 respectively,and those in ECA-IJV group were 0.861,0.890,0.641,0.656 respectively.However,AUC of BF and BV of three groups all had significant difference ( P ＜ 0.01 ).ConclusionsBoth BF and BV values calculated by three pairs of reference vessels had enough diagnosis efficiency for local recurrence and fibrosis,so all of the three groups of vessels may substitute each other in CT perfusion.

0.05).Conclusion The parameters of CT perfusion can be regarded as a surrogate index of tumor angiogenic activity pre-and post-radiotherapy in nasopharyngeal carcinoma.

Objective To study the value of CT perfusion in differential diagnosis of local recur and local radiofibrosis of nasopharyngeal carcinoma(NPC) at pre-and post-radiotherapy.Methods Dynamic CT scan was performed in 71 objectives: 14 in local recur group,22 in radiofibrosis group,15 in pre-radiotherapy NPC group and 20 in control group,the time-density curve(TDC) and the data of perfusion parameters were recorded and analyzed statistically.Results The TDC feature between local recur group,pre-radiotherapy NPC group and radiofibrosis group,control group had difference.The average of blood flow(BF) had significant differences by two by two comparison in four groups(P

Endothelial leukocyte adhesion molecule -1 ( ELAM -1 ) is a member of the cell adhesion molecules,which plays a great role in the distant metastasis of tumor in ligand interactions between sLe (x)and sLe(a).Recently,it becomes a new research hotspot on applying ELAM -1 in targeted cancer therapy.Many studies results show that by regulation of ELAM -1 in biological effects ,such as ELAM-1 and ligand inhibitors , monoclonal antibody ,targeting gene ,and other mediates of the path of blocking therapy ,thereby inhibiting or bloc-king tumor distant metastasis ,so as to achieve the purpose of tumor therapy and improve the prognosis .Therefore , ELAM-1 is expected to exert a critical role in the tumor targeted therapy .In this paper ,the application value of ELAM-1 in tumor related targeted therapy is reviewed .

Objective To measure hepatic blood flow of the normal liver and cirrhotic liver with hepatocellular carcinoma using multi-slice spiral CT(MSCT),and to evaluate the feasibility of the quantitative judgement of classification of liver cirrhosis with CT perfusion imaging.Methods CT dynamic perfusion imaging was performed in 53 subjects,including 32 patients of liver cirrhosis with hepatocellular carcinoma and 21 patients without liver disease(control subjects).The patients of liver cirrhosis with hepatocellular carcinoma were divided into three groups by CT morphologic classification :17 were classified as light liver cirrhosis group,8 as moderate group,7 as severe group.The parameters of CT perfusion included blood flow(BF),blood volume(BV),mean transit time(MTT),hepatic arterial fraction(HAF)and impulse residue function to(IRF To).The parameters were analyzed by the CT perfusion 3 software package(GE)with deconvolution method,and the correlation of the CT morphologic classification of liver cirrhosis with Child-Pugh functional classification was further evaluated.100 g-1,(17.81±6.59)ml/100 g,(9.52±3.08)s,0.20±0.08 and(4.38±2.35)s,respectively,while 0.27±0. 09 and (4. 14±2. 16)s, respectively. The mean BF, BV and HAF between normal livers and liver cirrhosis were statistically significant (P＜0. 05), and there were significant statistical differences in BF, BV and HAF among light, moderate and severe liver cirrhosis (P＜0. 05). The CT morphologic classification of liver cirrhosis was correlated positively with Child-Pugh classification (r=0. 935, P=0. 001 ). Conclusions Hepatic perfusion with MSCT can reflect the change of blood flow of cirrhotic liver, and MSCT perfusion can quantitatively evaluate the liver cirrhosis degree of patients with hepatocellular carcinoma.

Objective To explore the diagnostic performance of susceptibility weighted imaging (SWI) in distinguishing malignant from benign parotid lesions.Methods We prospectively evaluated preoperative SWI findings of 41 patients with 12 malignant and 29 benign parotid lesions by surgical pathology, and explore the intravenous distribution, the largest diameter of veins (dv-max), the number of veins per unit area (N/Svein) and the graduation of intratumoral susceptibility signal intensity (ITSS).The parameters was analyzed by Chi-square test, Independent t-test, Mann-Whitney U rank test and receiver operating characteristics (ROC) curves with SPSS 16.0 software.Results (1) For intravenous distribution, the benign ones mainly distributed around peripheral areas, accounting for 89.7％ (26/29), while the malignant ones were centrally distributed, making up 10/12.There were significant difference (x2=20.882, P=0.000) between benign and malignant ones.(2) The largest diameter of veins (dv-max) of benign and malignant lesions were (1.1±0.5) mm and (2.5 ± 1.0)mm respectively.There were significant difference (t=4.633, P=0.000) between benign and malignant ones.(3) The N/Svein of benign lesions were (0.80±0.92) per cm2, while that of malignant ones are (1.07±0.69) per cm2.The N/Svein (t=0.9143, P=0.367) was statistically insignificant.(4) For the graduation of ITSS,among benign lesions, there were 3 cases of grade 0, 22 cases of grade 1, 2 cases of grade 2 and 2 cases of grade 3.Meanwhile, there were 2 cases of grade 1, 5 cases of grade 2 and 5 cases of grade 3 among malignant lesions.When the Youden index reached the highest point, the optimal diagnostic threshold of dv-max and ITSS values were 1.75 mm and 1.5 mm, the corresponding area under the ROC curve (AUC) were 0.924 and 0.856 respectively.The sensitivity of d and ITSS ondiagnosis were 10/12 and 10/12, and the specificity of that were 96.6％ and 86.2％ respectively.The table shows that the sensitivity and specificity of intravenous distribution in diagnosis of malignant lesions are 10/12 and 89.7％.Conclusions The results provided evidence that SWI may be helpful in distinguishing malignant from benign parotid lesions, and it is worth to be generalized in clinical medicine.

Objective To evaluate the diagnostic performance of enhancement value and morphological features by using mul-tiphasic MDCT on differentiating untypical T4a from T3 gastric cancer.Methods Fifty-one histopathologically proven T3 and T4a gastric cancer patients with smooth serosa were collected retrospectively.Three radiologists read all images regarding morphological features,while the CT value and enhancement value of regions of interest (ROIs)located in the outer of lesion were calculated.Cut-off analysis was performed to determine optimal threshold levels of enhancement value to discriminate T4a and T3 gastric cancer.Di-agnostic performance of enhancement value and combination of enhancement value and morphologic assessment were compared with morphologic assessment by means of receiver operating characteristic (ROC)curve analysis.Results The sensitivity and specificity of morphological features was 66.67% and 33.33% respectively;the area under the ROC of enhancement value (between venous phase and plain scan)for differentiating T4a from T3 gastric cancer was 0.82,with a cut-off at 43.6 HU,sensitivity of 74.07% and specificity of 70.83%.Combined conventional standard and enhancement value,sensitivity of 100.00% and specificity 26.31%. Conclusion For differentiation of T4a and T3 gastric cancer by means of MDCT,enhancement value is found to be superior to con-ventional standard.

Objective To investigate the value of ADC histogram analysis in the assessment of response to neoadjuvant chemotherapy (NACT) in patients with in locally advanced breast cancer (LABC). Methods Thirty?five female patients with invasive ductal carcinoma proved by pathology before NACT and treated with operation after NACT were retrospectively analyzed. All patients were received MR examination (including non?enhanced MRI, enhanced?MRI, and DWI) breast before NACT. After neoadjuvant chemotherapy, 19 of 35 patients were categorized as responders and 16 were categorized as non?responders according response evaluation criteria in solid tumors criteria. Per?patient weighted ADC histograms were generated. Mean ADC, mode ADC, maximum ADC, minimum ADC, median ADC, skewness, and kurtosis were analyzed by using t test between responders and non responders groups. ROC curves were constructed to determine the optimum threshold for each histogram parameter to differentiate non?responders and responders in breast cancers. The optimal threshold values, determined by maximal Youden index were selected when significant differences existed in two groups. Results Mean, minimum, skewness, and kurtosis of ADC between responders and non?responders group were(0.955 ± 0.135)× 10?3mm2/s,(0.535 ± 0.115)×10?3mm2/s,0.85±0.61, 2.93±0.17,and(1.103±0.233)×10?3 mm2/s,(0.650±0.104)×10?3mm2/s,-0.42± 0.17, 3.11 ± 0.25,respectively. Significant differences were found mean ADC, minimum ADC, skewness, and kurtosis (t=2.345, 3.096, 8.051 and 2.524,P<0.05), and there was no differences in mode, median, maximum between responders and non?responders(P>0.05).We set the optimal threshold criteria of mean ADC (0.956×10?3mm2/s), minimum ADC (0.580×10?3mm2/s), skewness (0.890), sensitivity, specificity of three parameters for predicting responders in LABC were 73.7%,62.5%, 78.9%,68.8%, and 63.2%,75.0%, respectively, and the areas under ROC curve of mean ADC, minimum ADC, skewness was 0.678, 0.770, and 0.890, respectively. Kurtosis of responders and non?responders did not get cutoff value for much more overlap. Conclusion ADC histogram analysis is valuable in predicting LABC in patients with NACT effect, the minimum and skewness of ADC is highest sensitivity, specificity, respectively.

Objective To study the diagnostic value of 1.5T diffusion-weighted magnetic resonance imaging for small metastatic cervical lymph nodes of nasopharyngeal carcinoma(NPC),and to explore the optimal diagnostic threshold value of apparent diffusion coefficient(ADC)in small metastatic cervical lymph nodes of NPC.Methods 40 patients with histopathologically confirmed NPC were underwent conventional,enhanced and DWI MR.The mean ADC value of large metastatic cervical lymph nodes group,small metastatic cervical lymph nodes group and benign lymph nodes group were measured respectively.Statistical analysis was done by using the SPSS 1 6.0 program software.The receiver operating characteristic (ROC)curve was performed to obtain the ADC thresh-old value of small metastatic cervical lymph nodes and the diagnostic efficacy.Results The mean ADC value of large metastatic cer-vical lymph nodes group was (0.74±0.1 1)×10 -3 mm2/s,which was not significantly different from that in small metastatic cervical lymph nodes group(0.75±0.13)×10 -3 mm2/s,P >0.05.The mean ADC value in benign lymph nodes group was (1.05± 0.18)× 10 -3 mm2/s,which was significantly higher than that in large metastatic cervical lymph nodes group and small metastatic cervical lymph nodes group(P <0.05 ).Using a threshold ADC value of 0.908 × 10 -3 mm2/s for differentiating small metastatic cervical lymph nodes from benign lymph nodes,a sensitivity of 83.2% and specificity of 90.9% were obtained,the area under the ROC curve was 0.92.Conclusion DWI is helpful in the diagnosis of small metastatic cervical lymph nodes of NPC.

Objective To study 18F-deoxyglueose positron emission tomography computed tomo graphy(18 FDG PET-CT) in the diagnosis of cervical lymph node(LN) metastasis from rabbit nasopharyngeal VX2 carcinoma.Methods Nasopharyngeal VX2 carcinoma model using 30 rabbits was established. 18 FDG PET-CT,MRI and pathological diagnosis were performed and compared.ResultsFifty-three cervi cal LNs were picked up from resected specimens of 30 rabbits with nasopharyngeal VX2 carcinoma.There were 42 pathologically confirmed positive LNs.Positivity rate was significantly correlated with the volume and the shortest diameter of the LNs (r = 9.18,P =0.007 ; r = 2.77,P = 0.008).The diagnostic sensitivity of PET-CT was 96% (24/25) and 29% (5/17) for LNs with volume >0.5 cm3 and ≤0.5 cm3 ,83% (25/30) and 33% (4/12) for LNs with the shortest diameter ≥0.5 cm and < 0.5 cm,respectively.The diagnostic sensitivity,specificity and accuracy of PET-CT was 69% (29/42) ,100% (11/11) and 95% (40/42) ,com paring with 60% (25/42) ,91% (10/11) and 83% (35/42) of MRl,respectively.The volume measured by PET-CT images was not significantly different from the pathologically measured volume (t =-1.23,P = 0.233) ,while the volume measured by MRI was significantly different from the pathologically measured vol ume (t =-3.99,P = 0.001).Conclusions The sensitivity,specificity and accuracy of PET-CT are better than those of MRl,especially for the cervical lymph nodes with volume >0.5 cm3 or the shortest diameter ≤ 0.5 cm.PET-CT also can be used to detect the smaller metastatic lymph nodes,though the false negative rate is higher.