1.0T MR Free-hand Fluoroscopy Guided Biopsy Of Lesions And Ablation Of Tumors Located In Hepatic Dome

IntroductionLiver is a common organ for tumors,most of which were primary and secondary malignant tumors.Hepatocellular carcinoma(HCC)is the fourth cause of tumor-induced death followed by lung cancer,colorectal cancer and gastric cancer.Most intrahepatic tumors are occult and founded until middle and late stages,which induce the lost of opportunity for treatment.Therefore,early diagnosis of intrahepatic nodules is significant critical in the treatment of liver tumors.Presently,pathological puncture biopsy and other methods of tumor pathological diagnosis are important for the diagnosis of intrahepatic nodules.Recent years,local ablation has become popular in the treatment of hepatic malignant tumors.Besides,the efficacy of local ablation has achieved excellent clinical results.Presently,puncture biopsy and local ablation for intrahepatic lesions are mostly guided by imaging such as X-ray fluoroscopy,Ultrasound(US)and computed tomography(CT).However,it is a challenge for these guidance methods when the lesions are located in the hepatic dome.For example,ultrasonography is susceptible due to the influence of pulmonary bottom gas and ribs.The incidence of pulmonary injury and pneumothorax is high in transpulmonary-transhepatic puncture pathway for the puncture of hepatic dome leisions under CT-guided direct vision;percutaneous-transhepatic puncture(puncture from below costal diaphragm angle)needs to adjust the puncture angle and direction for many times due to its long path and large angle,which may increase intrahepatic hemorrhage and so on.Magnetic resonance imaging(MRI)offers superior soft tissue contrast and true multi-planar imaging capabilities,which can display the whole picture of the lesion from different sections.It also has effect of vascular void effect which helps display the peripheral blood vessels clearly without enhancement.Besides,typical MRI manifestations after ablation and no ionization are also the advantage of MRI.All of these advantages make magnetic resonance(MR)guidance to be an excellent guidance mode in the current imaging-guided puncture technology.Imaging-guided percutaneous ablation techniques such as radiofrequency ablation,microwave ablation,and cryoablation are considered as well-established methods to treat unresectable hepatocellular carcinoma because of their minimal invasiveness,high safety profile,and promising therapeutic efficacy.However,due to the special location of the hepatic dome carcinomas,it is difficult to puncture the tumors accurately,and also the ablation treatment for tumors at this position is a big challenge for clinicians.Hepatic dome carcinomas are close to the diaphragm,the bottom of the lung and the second porta hepatis,which makes it more difficult to monitor the tumors during ablation,and may cause more complications such as diaphragl and lung injury,pain and so on.Therefore,tumors in this region are often affected during ablation by some factors such as poor visualization of the lesions,patient's respiratory movement,intraoperative pain lead to reduce ablation power/time,diaphragm or lung thermal injury and so on.All of these may lead to inadequate ablation which can bring up lower tumor complete necrosis rate and higher incidence of complications.Cryoablation and microwave ablation have their own advantages for the treatment of hepatic dome malignant tumors,however,there are only few comparative study and ablation therapy guided by MR guidance.To the best of our knowledge,there is no report on the study of percutaneous puncture or ablation for hepatic dome lesions guided by LOT open MR with free-hand combined with fluoroscopy technique.The purpose of this study is to estimate the safety,feasibility and effectiveness of 1.0T open MR-guided percutaneous biopsy or ablation for lesions/tumors located in the hepatic dome with free-hand and fluoroscopy technique.The technical success rate,survival rate,local tumor progression rate and complications of the two groups were compared and analysed.Part I 1.0T MR free-hand fluoroscopy guided biopsy of lesions located in hepatic domeObjective:To prospectively estimate the safety,feasibility and accuracy of 1.0T open-magnetic resonance(MR)-guided percutaneous biopsy in free-hand of focal lesions located in the hepatic dome.Materials and methods:All percutaneous MR-guided biopsies of the lesions were performed at Shandong Medical Imaging Research Institute.Between October 2014 to November 2015,thirty-six patients with focal liver lesions located in the hepatic dome were included in this study(31 lesions were in the right lobe and 5 in theleft lobe).The mean lesions' diameter was 1.8±0.5 cm(maximum diameter range=0.6-3.6cm).Lesions were divided into two groups on the basis of maximum nodule diameters:<1.5cm(n=14)and>1.5 cm(n=22).Criteria for selected cases:(1)All lesions were located in the hepatic dome needed to be confirmed the pathological type;(2)Lesions with poor visibility at US or CT or with negative results of previous biopsy procedures by US or CT guidance;Criteria for exclusive cases:(1)Severe hemorrhage or shock;(2)Severe infection;(3)Coagulation dysfunction(international normalized ratio>1.5.or activated partial thromboplastin time over twice the normal value);(4)Untreatable thrombocytopenia(<50×109/L);(5)Contraindications to MRI such as installation of cardiac pacemaker status.All patients were put on the table of the MR system in a supine decubitus position.All the lesions underwent percutaneous biopsy by MR guidance using a 1.0-T open MR scanner with free-hand combined with MRfluoroscopy technique(Tl-FFE,TR 10 ms,TE 6.0 ms,flip angle 35?,slice thickness/separation 8 mm/-l mm,field of view 350×350,matrix 176x146,no breath hold or respiratory compensation trigger,acquisition time 1.6 s).Surgical pathology of nodules or clinical and imaging follow-up for at least 12 months were used to establish final diagnosis.Diagnostic accuracy,specificity,sensitivity,average procedure time and complications were recorded and analyzed.Results:All samples obtained were sufficient for diagnosis.The results of MRI guided percutaneous liver biopsy revealed 29(29/36,80.6%)malignant and 7(7/36,19.4%)benign lesions.The final diagnoses,according to independent surgical histopathological findings(n=26)or clinical follow-up(n=10),were 30 malignant and 6 benign lesions.In the 35(29 malignant and 6 benign)cases,surgical pathology(n=26)was consistent with biopsy results.Nine(4 malignant and 5 benign)cases were confirmed by clinical follow-up.Accuracy,sensitivity and specificity of MR-guided percutaneous liver lesions biopsy in diagnosing malignant tumors were 97.2%,96.7%and 100%,respectively.Accuracy,sensitivity and specificity were 92.9%,90.9%and 100%for the lesions that were 1.5 cm or smaller in diameter and 100%,100%and 100%for lesions larger than 1.5 cm in diameter,respectively.There was no significant difference between the two groups(P>0.05).The average procedure time for each pass of the needle from skin entry to the target lesion was 1.1 min and the total procedural time was 28.5 min.Biopsy-induced complications included peri-hepatic hemorrhage in 8.3%(3/36)of cases.No serious complications occurred.Conclusions:1.For biopsies of focal hepatic lesions located in the hepatic dome,MR-guided with free-hand and fluoroscopy technology could provide a near-real-time approach,which appears to be a safe and feasible approach with few complications.2.MR free-hand fluoroscopy guided biopsy for hepatic domes lesions can get high accuracy,specificity,sensitivity both in patients with lesions>1.5 cm and/or<1.5 cm in diameter.Part ? Clinical comparative analysis study of MR-guided cryoablation and microwave ablation of hepatic dome hepatocellular carcinomas with Free-hand Fluoroscopy Using 1.0T Open High-field ScannerObjective:To valuate and compare the safety and effectiveness of 1.OT open magnetic resonance guided and monitored percutaneous cryoablation and microwave ablation of hepatice dome hepatocellular carcinoma(HCC).Materials and Methods:This study retrospectively analyzed 76 patients with hepatic dome HCCs underwent percutaneous cryoablation or microwave ablation under the guidance of magnetic resonance imaging during November 2014 to April 2017.The patients were divided into two groups according to the different treatment method:cryoablation group(n=37)and microwave ablation group(n=39).The maximum diameter of all lesions ranged from 0.7 cm to 4.0 cm.In all cases,the distance between the tumor and the hepatic dome was no more than 10 mm.In the cryoablation group,the median lesion maximum diameter was 2.9 cm,28 lesions were located in the right lobe(segments ? and ?)and 9 lesions in the left lobe(segment IVa).In the microwave group,the median lesion maximum diameter was 3.1 cm,31 lesions were located in the right lobe(segments ? and ?)and 8 lesions in the left lobe(segment IVa).Criteria for selected cases:(1)An HCC lesion with a maximum diameter of 4 cm or less in the hepatic dome;(2)No prior HCC treatment such as surgical resection,transhepatic arterial chemoembolization,Radiotherapy and chemotherapy,et al;(3)no prior HCC treatment,no invasion of the portal vein or the hepatic vein trunk,no extrahepatic HCC metastases;(4)Child-Pugh-Turcotte class A or B liver function,serum bilirubin level less than 51.3?mol/L,Eastern Cooperative Oncology Group Performance Status of 2 or less;(5)unresectable tumor or patient was reluctant to undergo surgery therapy.Criteria for exclusive cases:(1)Severe decompensated cirrhosis with massive ascites,coagulation dysfunction(international normalized ratiol.5,or activated partial thromboplastin time over twice the normal value,or platelet count<60×109/L);(2)Severe heart,lung,kidney dysfunction,severe infection,severe hemorrhage or shock,et al;(4)Patients with advanced malignant cachexia;(4)Contraindications to MRI such as installation of cardiac pacemaker status.MR fluoroscopy with freehand technique was applied in the procedure.The success rate and complications of magnetic resonance guided operation were recorded and compared between the two groups.Patients were followed up for at least 12 months after the ablation therapy or until death.Supplementary cryoablations or microwave ablations under MR guidance were perfonned in patients who were found with tumour progression during the follow-up period.The success rate,survival period,local tumor control and complications were recorded,calculated and compared between the two groups.Results:MR-guided percutaneous cryoablation or microwave ablation were successfully performed on all 76 patients with hepatic dome liver cancers.The technical success rate was 100%in the both two groups.The median follow-up time was 21.0 months(range,10-26 months)and 19.5 months(range,8-25 months),repectively.Of the 37 patients underwent cryoablation,two patients with local tumor progression at the 4th and 11th month after the procedure were treated with a supplementary cryoablation.One patient died of upper gastrointestinal hemorrhage at the 1oth month after cryoablation.While in the microwave group,there were five patients with local tumor progression received supplementary microwave ablation at 5th,8th,9th,10th and 11th months after albation,respectively.Two patients died in the group,one died of upper gastrointestinal hemorrhage at the 8th month after microwave ablation,the other died of cerebral haemorrhage at the 12th after.At the 6th month after operation,the local tumor progression and overall survival rates in the cryoablation group and microwave ablation were 2.7%(1/37),100%(37/37)and 2.6%(1/39),100%(39/39),respectively,which had no difference betweent the two groups.The rates at the 12th month were 5.4%(2/37),97.3%(36/37)and 12.8%(5/39),94.9%(37/39)at 1 year,respectively.Log-rank test shows that the local tumor progression rate of cryoablation group is lower than microwave ablation(P?0.0295),while the overall survival rate is similar(P=0.5899).The visual analog scale score(VAS)during the operation in the cryoablation gFroup and microwave ablation were 4.0,6.5,respectively,and 1.8,3.5 3 days after,respectively,and there were statistical differences between the two groups(P=0.035;p=0.028).In the cryoablation grouP,mildly decreased platelet count levels were observed 3 days after the procedure(p=0.000),whereas there was no significant difference 7 days after the procedure(p=0.141),while the levels did not change before and after the microwave ablation(P=0.168,p=0.235).There were two patients in each group with postoperative hydrothorax that required chest tube drainage,respectively,and no other serious complications occurred.Conclusions:1.1.0T open magnetic resonance guided cryoablation and microwave ablation are both feasible,safe and effective therapy methods for the treatment of hepatic dome hepatocellular carcinomas.2.The overall survival rates were similar in the both groups at 1 year,while the local tumor progression was lower in the cryoablation groups.3.The VAS score during the cryoablation procedure was lower than that of the microwave ablation,the platelet count levels decreased 3 days after the cryoablation and turned back 7 days after the procedure.Microwave ablation had no significant impact on the platelet count levels.No other serious complications occurred in the two groups.