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Objective To compare the size of the internal target volume (ITV),biological target volume (BTV) and internal biological target volume (IBTV) based on PET-CT and 4DCT for primary nonsmall cell lung cancer (NSCLC),as well as try to apply IBTV in radiotherapy planning.Methods A total of 15 patients with NSCLC were sequentially scanned by an axial enhanced 3DCT,4DCT and 18F-FDG PET-CT in the thoracic region.The gross target volumes (GTVs) of ten phases of 4DCT images were contoured,and ITV was obtained by fusion of ten GTVs.BTV based on PET-CT images was determined by the SUV 2.0.The IBTV was defined by fusion of ITV and BTV.Planning target volumes (PTVs) based on ITV,BTV,and IBTV (PITV,PBTV,PIBTV) were obtained by ITV,BTV and IBTV with a 10-mm expansion respectively.The metrics of PIBTV,PITV and PBTV were compared,and the planning parameters of target volumes and risk organs were evaluated.Results There was no significant difference between ITV and BTV,but there was significant difference between IBTV and ITV and BTV (F=22.533,P ＜ 0.05).To include more than 95％ volume of IBTV,it is necessary to expand the margin of 9.0(6.0,12.0)mm based on BTV or 10.00(7.0,12.0)mm based on ITV.There was no significant difference between the two groups (P ＞ 0.05).Dice's similarity coefficient of BTV and ITV was 0.72(0.54,0.79).The intensity modulated radiotherapy plan based on PBTV can guarantee 85.6％ (80.5％,91.2％) of PITV to reach the prescription dose,compared with 80.2％ (74.4％,87.6％) of PBTV by the plan from PITV.Additionally,the conformity index and homogeneity index were not ideal.The dosimetric parameters of PITV and PBTV in the PIBTV plan were much better than those in PBTV-and PITV plan.Conclusions The radiotherapy plan based on PET-CT or 4DCT could not guarantee a reasonable dose distribution of PTV expanded from ITV or BTV.Thus,using IBTV for radiotherapy is advised.
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Objective To investigate the differences in position and volume between planning target volumes (PTV) based on positron emission tomography?computed tomography (PET?CT) images with an standardized uptake value ( SUV) no less than 2?5, 20% of the maximum SUV ( SUVmax ), or 25% of SUVmax , three?dimensional ( 3D ) CT, and four?dimensional ( 4D ) CT in thoracic esophageal cancer. Methods Eighteen patients with thoracic esophageal cancer sequentially received chest 3DCT, 4DCT, and [18F]fluoro?2?deoxy?D?glucose (FDG) PET?CT scans. PTV3D was obtained by conventional expansion of 3DCT images;PTV4D was obtained by fusion of target volumes from 10 phases of 4DCT images. The internal gross tumor volumes ( IGTV) , IGTVPET2.5 , IGTVPET20%, and IGTVPET25%, were generated based on PET?CT images with an SUV no less than 2?5, 20% of SUVmax , and 25% of SUVmax , respectively. These IGTVs were expanded longitudinally by 3?5 cm and radically by 1 cm to make PTVPET2.5 , PTVPET20%, and PTVPET25%, respectively. Results PTV3D was significantly larger than both PTV4D and PTVPET(P=0?000 -0?044), while there was no significant difference between PTV4D and PTVPET ( P= 0?216 -0?633 ) . The mutual degrees of inclusion ( DIs ) between PTV3D and PTV4D were 0?70 and 0?95, respectively, which were negatively correlated with 3D?Vector ( P=0?039). The mutual DIs between PTVPET2.5, PTVPET20%, and PTVPET25% were 0?74, 0?72, 0?78, 0?73, 0?77, and 0?70, respectively, which showed no correlation with 3D?Vector (P=0?150 -0?822). The mutual DIs between PTV3D and PTVPET were 0?86, 0?84, 0?88, 0?63, 0?67, and 0?59, respectively. Conclusions It is difficult to achieve complete volumetric overlap of PTVs based on 3DCT, 4DCT and PET?CT in thoracic esophageal cancer due to different target volume information. PET scan during free breathing should be used with caution to generate PTVs in thoracic esophageal cancer.
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Objective To investigate the correlations in target volumes based on positron emission tomography CT (PET/CT) and the end-expiration phase of four-dimensional CT (4D-CT) images for non-small cell lung cancer (NSCLC).Methods Seventeen patients with NSCLC sequentially underwent three-dimensional CT (3DCT),4D-CT and 18F-FDG PET/CT thoracic simulation scans.The gross target volume (GTV) was contoured on the end-expiration phase (50％) of 4D-CT and defined as GTV50％.The internal gross target volumes (IGTV) based on PET/CT images (IGTVPET) were determined by the standardized uptake value (SUV) 2.0 (IGTVPET2.0) and 20％ percentage of the maximal standardized uptake value (SUVmax) (IGTVPET20％).The following parameters were calculated to analyze the correlation between IGTVPET and GTV50％ in volume ratio (VR) and conformity index (CI):maximum transverse diameter of GTV50％,volume of GTV50％,the displacement of GTV in the cranial-caudal direction and 3D Vector calculated from 4D-CT dataset as well as the SUVmax.Results There was no significant correlation between the VR of IGTVPET2.0 to GTV50％ and the maximum transverse diameter of GTV50％,volume of GTV50％,the displacement of GTV in the cranial-caudal direction,3D Vector and the SUVmax (P ＞ 0.05).The VR between IGTVPET20％ and GTV50％ inversely related to maximum transverse diameter of GTV50％,volume of GTV50％ and SUVmax (r =-0.663,-0.669,-0.752,P ＜0.05).The CI between IGTVPET2.0 and GTV50％ positively related to volume of GTV50％ and maximum transverse diameter of GTV50％ (r =0.613,0.483,P ＜ 0.05).Conclusions 3D PET images provide a time-averaged image of the tumor during the numerous breathing cycle.They fail to include the full information of moving tumor.The target volumes based on 3D PET might not reflect the real IGTV of NSCLC.
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Objective To discuss the clinical features of HbeAg-negative chronic hepatitis B patients associate with non-alcoholic fatty liver disease (NAFLD), to value the effect of combining treatment on fatty liver influence and antivi-ral therapy. Methods Nighty eight chronic hepatitis B patients with non-alcoholic fatty liver disease (NAFLD) (Liver pa-thology G≥2 or S≥2,HBV DNA>1 × 105 copies/mL), were observed and given antiviral therapy with interferon alpha 1 b for 24 weeks. These patients were divided into combined treatment group (55 cases treated with interferon alpha 1 b combined with Jian Gan Jiang Zhi pills) and control group (43 cases treated with interferon alpha 1 b) in accordance with random num-ber table. All these patients took Leucoson to prevent blood cells reduction. The combined treatment effect was analyzed by observing and comparing biochemical serum change and HBV DNA negative conversion ratio between two groups. Re-sults After 24 weeks of antiviral therapy in Chronic hepatitis B patients with negative HBeAg associated with NAFLD, ALT and AST decreased significantly in both treatment group and control group. And this change is more obvious in treat-ment group than in control group. TC and TG in treatment group and TC in control group were also dropped with treatment (P<0.05). There is significant difference on HBV DNA negative conversion ratio between treatment groupand control group (98.2%vs 86.0%,P<0.05). Conclusion The combination of antiviral treatment and anti fatty liver treatment can obviously improve liver function and blood lipids, increase negative conversion ratio of HBV DNA for chronic hepatitis B patients asso-ciated with NAFLD.
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Objective To compare volumetric size, conformity index (CI), degree of inclusion (DI) of internal gross target volumes (IGTV) delineated on 4D-CT-MIP and PET-CT images for primary thoracic esophageal cancer. Methods Fifteen patients with thoracic esophageal cancer sequentially underwent enhanced 3D-CT, 4D-CT and PET-CT simulation scans. IGTVMIP was obtained by contouring on 4D-CT maximum intensity projection ( MIP). The PET contours were determined with nine different threshold methods (SUV≥2?0, 2?5, 3?0, 3?5), the percentages of the SUVmax(≥20%, 25%, 30%, 35%, 40%) and manual contours. The differences in size, conformity index (CI), degree of inclusion ( DI) of different volumes were compared. Results The volume ratios ( VRs) of IGTVPET2. 5 to IGTVMIP , IGTVPET20% to IGTVMIP, IGTVPETMAN to IGTVMIP were 0?86, 0?88, 1?06, respectively, which approached closest to 1. The CIs of IGTVPET2?0,IGTVPET2.5,IGTVPET20%,IGTVPETMAN and IGTVMIP which were 0?55, 0?56, 0?56, 0?54,0?55, respectively, were significantly larger than other CIs of IGTVPET and IGTVMIP (Z= -3?408-2?215,P 0?05). Conclusions The targets delineated based on SUV threshold setting of≥2?5, 20% of the SUVmax and manual contours on PET images correspond better with the target delineated on maximum intensity projection of 4D-CT images than other SUV thresholding methods.
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<p><b>OBJECTIVE</b>To study the prevention and treatment of HBV reinfection after liver transplantation.</p><p><b>METHODS</b>Total 19 cases of chronic fulminant hepatitis B, the end-stage of liver cirrhosis and liver carcinoma complicated with HBV cirrhosis. Were performed liver transplantation and given anti-viral drugs pre and post transplantation. Famciclovir was administered in 4 cases, lamivudine in 13 cases and lamivudine+HBIG in 2 cases. The serum HBVM and liver biopsy immunohistochemistry were performed.</p><p><b>RESULTS</b>Four cases given famciclovir developed reinfection. Serum HBsAg, HBeAg and HBV DNA were positive in 3 cases. Liver biopsy immunohistochemistry showed HBsAg and HBeAg phenotype. Classical viral hepatitis in 1 case occurred, three cases died. In the lamivudin group 7 cases showed positive for HBsAg, 2 cases positive for HBV DNA, 4 cases HBsAg or HBcAg phenotype. One case showed positive for serum anti-HBc the other negative for HBVM, and liver biopsy immunohistochemistry was negative too.</p><p><b>CONCLUSIONS</b>These date suggest that anti-virus prevention and treatment in pre and post liver transplantation with HBV infected correlative disease is necessary, feasible and effective.</p>