Study Of MR In Evaluating The Short-term Efficacy Of Cyberknife Treatment For Locally Advanced Pancreatic Cancer

Part Ⅰ Study of short-term clinical efficacy of Cyberknife treatment for locally advanced pancreatic cancerObjective: to initially explore the short-term curative efficacy and characteristics of Conventional MRI sequence for target lesion before and after Cyberknife radiotherapy.Methods: Cyberknife was assessed clinically and radiographically for all the patients with locally advanced pancreatic cancer both before and after Cyberknife radiotherapy.Karnofsky Score(KPS)and Visual Analogue Scale Score(VAS)are used respectively to evaluate the patients’ life and pain.RECIST1.1 was used to evaluate the change of the target lesions’ longest diameter.The singnal value of T1 WI and T2 WI was also evaluated.Result: 35 cases finished all follow-up examinations,34 patients are stable,1 was PR,1 case was lost.KPS: KPS has significant growth trend(P<0.001).KPS of both one month and three months after radiotherapy were statistically higher than that of before radiotherapy(93.33±10.69 vs 72.47±14.74,P<0.001;92.86±10.73 vs 72.47±14.74,P<0.001).VAS Score:VAS has significant growth trend(P<0.001).VAS of both one month and three months after radiotherapy were statistically lower than that of before radiotherapy(1.08±2.06 vs 4.89±2.89 P<0.001;0.51±1.48 vs 4.89±2.89,P<0.001).There is no statistically significant change among three groups of signal value of T1 WI and T2 WI.Conclusion: Knife is effective means for the pain relief,local control and living conditions improving of LAPC in a short span of time.Conventional MRI sequence may not be able to sensitively reflect the changes of micro-structure of tumor on time.Part Ⅱ Study of single b value DWI in evaluating the short-term efficacy of Cyberknife treatment for locally advanced pancreatic cancerObjective:to initially explore the value of single b value DWI in the short-term efficacy evaluation of Cyberknife treatment for locally advanced pancreatic cancer.Methods: Before Cyberknife radiotherapy,as well as at 1 month and 3months after radiotherapy,Conventional MRI scans and respiratory triggered DWI(SS-EPIDWI,r FOV DWI)were performed to get the ADCs.Observe the ADCs changing tendency and the correlation of change of both ADCs and clinical indexes(KPS,VAS).Result:35 cases finished all follow-up examinations,1 case was lost over 3 months following Cyberknife treatment.ADC(SS-EPIDWI):ADC(SS-EPIDWI)has significant growth trend(P<0.001).ADC of both one month and three months after radiotherapy were statistically higher than that of before radiotherapy(1.79±0.33 vs 1.47±0.28,P<0.001;1.94±0.41 vs 1.47±0.28,P<0.001).ADC(r FOVDWI): ADC(r FOVDWI)has significant growth trend(P=0.001).before treatment(),ADC of both one month and three months after radiotherapy were statistically higher than that of before radiotherapy(1.17±0.37 vs 0.96±0.33,P=0.012);1.21±0.27 vs 0.96±0.33,P=0.001).For target lesions,both ADCs(SS-EPIDWI,r FOVDWI)increased as a function of time,time effect(P<0.001),group effect(P < 0.001),no interactive effects were revealed between time and group(P=0.0886).Three months after treatment,there is a certain correlation between the change of ADC(r FOVDWI)and VAS,Pearson correlation coefficient was-0.471,P = 0.004.Conclusion: After Cyberknife treatment,both ADCs(SS-EPIDWI,r FOVDWI)has a tendency to increase,reflecting that water moleculars’ s diffusion movement ability of target lesions had the same increasing trend after treatment.Compared to Conventional MRI sequence,ADCs(r FOVDWI)is more sensitive index which monitors pain relief.ADCs(SS-EPIDWI,r FOVDWI)are potential evaluation method in tumor activity,Part Ⅲ Study of multiple b value DWI in evaluating the short-term efficacy of Cyberknife treatment for locally advanced pancreatic cancerObjective: to initially explore the value of multiple b value DWI(3.0T)in the short-term efficacy evaluation of Cyberknife treatment for locally advanced pancreatic cancer.Methods: Before Cyberknife radiotherapy,as well as at 1 month and 3months after radiotherapy,all the patients got both Conventional MRI sequence scans,and Multiple b value DWI sequence scans.b values are 0 s/ mm2,25s/ mm2,50 s/ mm2,75 s/ mm2,100 s/ mm2,150 s/ mm2,200 s/ mm2,400 s/ mm2,600 s/ mm2,800 s/ mm2,1000 s/ mm2.Complete the assessment of all the parameters(ADCtot,f,Dfast,Dslow)before and after treatment.Results: 35 cases finished all follow-up examinations,only 1 case was lost over the 3 months after Cyberknife treatment.ADCtot : ADCtot has significant growth trend(P<0.001).Before treatment(1.56±0.29),one month later(1.75±0.32),the difference was statistically significant(P=0.009);Dslow:Dslow has significant growth trend(P=0.041).Before treatment(1.10±0.73),three months later(1.49±0.46),the difference was statistically significant(P=0.009).Conclusion:Both ADCtot and Dslow can reflect that water moleculars’ s diffusion movement ability of region-of-interest gradually enhanced at micro level.as a function of time after Cyberknife treatment.