Value Of Deconvolution-based Perfusion CT Imaging In Differentiating Primary Benign Bone And Soft-tissue Tumors From Malignant Ones

Part one Value of Deconvolution-based Perfusion CT Imaging in Differentiating Primary Benign Bone and soft-tissue Tumors from Malignant OnesObjective1.To explore the diagnostic feasibility of CT perfusion imaging(CTPI) in tumors of Bone and soft-tissue Tumors2.To investigate the hemodynamic features of primary Bone and soft-tissue Tumors using CTPI3.To use CTPI to assess the tumor vascularity in primary Bone and soft-tissue Tumors3.To investigate the hemodynamic features of primary Bone and soft-tissue Tumors using CTPI4.To explore the clinical feasibility of CT perfusion imaging(CTPI) in Differentiating Primary Benign Bone and soft-tissue Tumors from Malignant Ones.Material and methods1.Patientsfrom September 2007 to October 2008,We prospectively attempted CTPI in fifty consecutive patients with primary Bone and soft-tissue Tumors confirmed by pathology in in-patient clinic of Nanjing General Hospital of Nanjing Military Command PLA as part of a pilot feasibility study.Inclusion criteria for this study were as followspatients with primary Bone and soft-tissue Tumors confirmed by cytologic and histologic techniques.with measurable tumor lesions by CT,chest CT scan with no evidence of pulmonary metastasis or distant metastasis.exclusion criteria for this study were as followspatients with a global deterioration of health status.with a history of prior radiation,chemotherapy or surgery, positive pregnancy test.second primary,hypersensitiveness to iodine.With renal disease and liver disease.All patients were informed of the investigational nature of the study and signed a written consent for participation.groupingmalignant group(n=40).25 men and 15 women,ages ranged from 12 to 75 years(median age,32 years).The primary sites,pelvis(n=15),distal femur(n=12),thigh(n=4),proximal tibia (n=3),proximal humerus(n=2),proximal fibula(n=1),lumbar vertebrae(n=1),leg (n=1) and popliteal fossa(n=1).The pathological types.osteosarcoma in 19 cases,chondrosarcoma in 10 case, primitive neuroectodermal tumor(PNET)in 7 cases,Liposarcoma in 2 cases, malignant fibrous histiocytoma(MFH) in 1 case,and synovial sarcoma in 1 case.benign group(n=10).7 men and 3 women,ages ranged from 12 to 62 years(median age,39.5 years).The primary sites,pelvis(n=6),distal femur(n=1),thigh(n=1),proximal tibia (n=1) and distal tibia(n=1).The pathological types:giant cell tumor of bone in 5 cases,neurofibroma in 2 cases,neurilemmoma in 2 cases and hemangioma in 1 case.2.Imaging StudiesSiemens 64-slice Spiral CT(Somatom,Senation,Germnay)Omnipaque(350 mg/ml,100ml,350 mg/ml,50ml,Manufacturer:GE Healthcare(Shanghai) Co Ltd.Approval Number:350 mg/ml^*50ml:H20000597.350 mg/ml^*100ml:H20000599).Power injector(Optivantage^TMDH,pattern number:MALLINCKRODT)Commercial Perfusion software(Syngo Body PCT Perfusion software,Siemens, Germnay)Software for 3D reconstruction(Space Software,Siemens,Germnay).All the patients were fasting 4 hours before the CT scans on a multidetector scanner(siemens 64-slice Spiral CT).A noncontrast CT was performed to determine the tumor position,which provided the maximal horizontal tumor area.For the CTP study,patients received a power injection of nonionic iodinated contrast agent Omnipaque 1.5ml/kg(350 mg/ml^* 50ml) 50ml at 6 ml/s via median antecubital vein using a Power injector.At 5 seconds into the injection,a cine(continuous) acquisition was initiated by using the following parameters:100 kV,80 mA,4×7.2 mm sections,5 seconds rotation for duration of 25seconds. For the CT reconstruction study,patients received a power injection of nonionic iodinated contrast agent Omnipaque 1.5ml/kg(350 mg/ml^*1000ml) 80ml and normal saline in turn via median antecubital vein.at 6 ml/s.At 5 minutes into the injection,a volume acquisition was initiated by using the following parameters:100 kV,80 mA,0.6 mm sections,.Region of Interest(ROI) of arterial phase was placed in the aorta descendens.the scan was triggered when the net bonus of CT value in aorta descendens reached 100Hu(dose care).Data was done by the Space software for the 3D reconstruction of tumors and vessels.The perfusion data were postprocessed by using a commercial software package(syngo Body PCT,Siemens,Germany) based on a deconvolution-based technique.ROI A user-defined ROI was drawn freehand by an experienced radiologist major in bone and soft tissue,incorporating as much of the solid portions of the tumor identified on the noncontrast localizing images as possible and omitting the necrotic regions,blood vessels,calcification,air and subcutaneous fat.Care was also taken to avoid encroaching on tumor boundaries to exclude peritumoral hyperemia.The data were processed into maps or perfusion paramemeters as followsblood flow(BF,in ml·min^-1·100g^-1.the volume flow rate of blood through the vasculature in a tissue.),blood volume(BV,in ml·100g^-1,the volume of blood within the vasculature of a tissue that was flowing and not stagnant.)time to peak(TTP,in seconds,the time taken by the blood elements to achieve the peak of the TDC.)capillary permeability surface product(PS,in ml·min^-1·100g^-1,the product of permeability and the total surface area of capillary endothelium in a unit mass of tissue representing the total diffusional flux across all capillaries.)time-density curve(TDC).The X-axis was the time of perfusion,the Y-axis was the bonus of the value of CT,demonstrating the changement of perfusion of the tissue.3D reconstruction of tumor vessels3.Data and StatisticalAll the data were processed by Spss13.0 for windows.All the data were noted in Median(M) and Quartile(QR);To determine the statistically significant difference in CTPI parameters (BF,BV,TTP and PS) between malignant group and benign group,the Wilcoxon rank sum test,a nonparametric test for nonpaired data,was employed.Statistical significance was set at P＜0.05ResultsCTPI of the tumors were feasible in all of the fifty patients(100%).No adverse reactions to the contrast agent were encountered..The TDC between malignant group and benign group was different from each other,The TDC of malignant group achieved the peaking fast and showed a high peaking values.It performed as tachy-ascensus model,the curve stayed unchanged for a time or descended slowly.The TDC of benign group achieved the peaking more slowly than that of the malignant group and showed lower peaking values.However.The curve ran smoothly and softlyThe perfusion parameters of the malignant group were noted in Median(M) as follows:BF 41.700 ml·min^-1·100g^-1;BV 60.250ml·100g^-1;TTP 122.000 s;PS 42.750 ml·min^-1·100g^-1.The perfusion parameters of the benign group were noted in Median(M) as follows:BF 24.000 ml·min^-1·100g^-1;BV 29.550 ml·100g^-1;TTP 125.500s;PS 23.050 ml·min^-1·100g^-1.Wilcoxon rank sum test analysis showed a significant difference between the malignant group and benign group in BF,BV and PS,(U=101.500,P=0.015; U=92.000,P=0.008 and U=83.000,P=0.004 respectively),with the malignant group having relatively higher BF,BV and PS.Witcoxon rank sum test analysis showed no significant difference between the malignant group and benign group in the value of TTP,(U=169.500,P=0.465).There were different three-dimensional nutritional tumor vessel quantity and patterns between malignant and benign groups.Abundant nutritional tumor vessels were demonstrated in malignant group.while the vessel quantity of benign group was comparatively less,Encircled vascular patterns and basket vascular patterns were the characterization of benign group,however,irregular and penetrating vascular patterns were the characterization of malignant tumor.Conclusion1.Perfusion CT offers potential for noninvasive and quantatitive monitoring of hemodynamic features in patients with primary bone tumors.and overcomes the incapability of general CT to reflex anatomic and morphological alteration.2.These preliminary results show that CTPI can be used in tumors of bone-muscle system and is worthy of clinical generalization.3.TDC,BF,BV and PS tend to be useful for differentiating benign and malignant primary bone tumors.4.As a non-invasive and convenient method,CTPI provides more detailed vascular information of Bone and soft-tissue Tumors.Part two clinical value of Deconvolution-based Perfusion CT Imaging in Primary Bone and soft-tissue Tumors in pelvisObjective 1.To explore the diagnostic feasibility of CT perfusion imaging(CTPI) in tumors of Bone and soft-tissue Tumors in pelvis2.To investigate the hemodynamic features of primary Bone and soft-tissue Tumors in pelvis using CTPI3.To use CTPI to assess the tumor vascularity in primary Bone and soft-tissue Tumors in pelvis3.To investigate the hemodynamic features of primary Bone and soft-tissue Tumors in pelvis using CTPI4.To explore the clinical feasibility of CT perfusion imaging(CTPI) in Differentiating Primary Benign Bone and soft-tissue Tumors in pelvis from Malignant Ones.Material and methods1.Patientsfrom September 2007 to October 2008,We prospectively attempted CTPI in twenty-one consecutive patients with primary pelvic Bone and soft-tissue Tumors confirmed by pathology in in-patient clinic of Nanjing General Hospital of Nanjing Military Command PLA as part of a pilot feasibility study.Inclusion criteriaThe same as part one.exclusion criteriaThe same as part one.All patients were informed of the investigational nature of the study and signed a written consent for participation.groupingpelvis -malignant group(n=15).11 men and 4 women,ages ranged from 16 to 69 years(median age,41 years).The pathological types:osteosarcoma in 2 cases,chondrosarcoma in 7 case, primitive neuroectodermal tumor(PNET)in 5 cases and malignant fibrous histiocytoma(MFH) in 1 case.pelvis -benign group(n=6).5 men and 1 woman,ages ranged from 22 to 57 years(median age,37.5 years).The pathological types:giant cell tumor of bone in 2 cases,neurofibroma in 2 cases,neurilemmoma in 2 cases.2.Imaging StudiesThe same as part one..The data were processed into maps or perfusion paramemeters as followsblood flow(BF,in ml·min^-1·100g^-1),blood volume(BV,in ml·100g^-1)time to peak(TTP,in seconds)capillary permeability surface product(PS,in ml·min^-1·100g^-1) time-density curve(TDC).3D reconstruction of tumor vessels3.Data and StatisticalAll the data were processed by Spss 13.0 for windows.All the data were noted in Median(M) and Quartile(QR);To determine the statistically significant difference in CTPI parameters (BF,BV,TTP and PS) between pelvis -malignant group and pelvis-benign group,the Wilcoxon rank sum test,a nonparametric test for nonpaired data,was employed.Statistical significance was set at P＜0.05ResultsCTPI of the tumors were feasible in all of the twenty-one patients(100%).No adverse reactions to the contrast agent were encountered.The TDC between the malignant-pelvis group and benign-pelvis group was not different from each other,The TDC of the two group achieved the peaking fast and showed a high peaking values,the curve stayed unchanged for a time or descended slowly.The perfusion parameters of the pelvis -malignant group were noted in Median (M) as follows:BF 28.100 ml·min^-1·100g^-1,BV 49.100ml·100g^-1;TTP 121.000s;PS 39.200 ml·min^-1·100g^-1.The perfusion parameters of the pelvis- benign group were noted in Median(M) as follows:BF 24.000ml·min^-1·100g^-1;BV 29.550ml·100g^-1;TTP 122.500s;PS 20.950 ml·min^-1·100g^-1.Wilcoxon rank sum test analysis showed a significant difference between the malignant-pelvis group and benign-pelvis group in PS(U=15.000,P=0.018),with the malignant-pelvis group having relatively higher PS.Wilcoxon rank sum test analysis showed no difference between the malignant-pelvis group and benign-pelvis group in BF,BV and TTP, (U=29.000,P=0.235;U=26.000,P=0.154 and U=43.000,P=0.910 respectively).CTPI not only demonstrated the site,size,and 3D contour of the tumors,but also clearly displayed the 3D spatial relationship of the tumors,the deviation of vessels by the tumors as well as bone destruction and enlargement of the periosteum.conclusion1.These preliminary results show that CTPI can be used in tumors of pelvic Bone and soft-tissue Tumors and is worthy of clinical generalization.2.PS tends to be useful for differentiating benign and malignant primary Bone and soft-tissue Tumors.in pelvis3.CTPI provides more detailed vascular information of tumor feeding arteries, draining veins and invaded vessels,which is good for diagnosis and therapy of tumor.