conventional open surgery is the preferred treatment for tumor resection , as is for intrahepatic bile duct stones , especially in patients who have undergone previous upper abdominal surgery . in recent decades ,
continuous innovation and improvement of laparoscopic equipment and technology have led to the evolution of laparoscopic hepatectomy from a challenging procedure performed by highly skilled surgeons in handful medical centers to one that is widely performed .
however , few laparoscopic hepatectomy procedures have been reported for patients with previous upper abdominal surgery . because severe adhesions secondary to previous surgery can lead to higher rates of complication and conversion to open surgery ,
the aim of this study was to evaluate the feasibility and safety of laparoscopic hepatectomy in these patients .
prior to data collection , the study protocol was evaluated and approved by the ethical committees for human subjects at sir run run shaw hospital affiliated to medical college of zhejiang university .
three hundred and thirty - six patients who had undergone laparoscopic hepatectomy at our hospital from march 2012 to june 2015 were included in this retrospective study .
we divided these patients into two groups : an experimental group of those who had undergone previous upper abdominal surgery ( ps group , n = 42 ) and a control group of those who had not ( ns group , n = 294 ) .
previous upper abdominal surgery was defined as surgery performed above the umbilical region , including hepatobiliary and pancreatic surgery , splenectomy and gastrectomy , and surgery involving the small intestine , colon , kidney , and upper abdominal retroperitoneum . in this study ,
laparoscopic hepatectomy included malignant or benign primary hepatic tumors , metastatic hepatic carcinoma , and intrahepatic duct stones .
inclusion criteria were : ( 1 ) primary hepatic malignant tumors with no extrahepatic metastasis ; metastatic hepatic tumors that metastatic focuses were limited to one lobe of liver ; benign hepatic tumors that were obviously symptomatic , at high risk for rupture with life - threatening consequences , or with unclear diagnosis ; intrahepatic duct stones with obvious stricture or dilation of the bile duct and liver atrophy ; ( 2 ) child - pugh score a or b ; ( 3 ) well - preserved general condition .
patients with severe portal hypertension or american standards association ( american society of anesthesiologists )  grade iii or future liver remnant insufficiency ( < 30% in the nonsclerotic liver or < 40% in the liver with cirrhosis ) were excluded .
briefly , a 10 mm camera trocar was inserted subumbilically in the ns group and in where adhesions were expected to be minimal in the ps group .
pneumoperitoneum was established with carbon dioxide to a pressure of 1215 mmhg ( 1 mmhg = 0.133 kpa ) . under laparoscopic guidance ,
three more ports were established : a 10 mm main port in the xiphoid for surgical manipulation and two 5 mm accessory ports on the right side of the abdomen . for major liver resection ,
the hepatic hilum was dissected , and liver parenchymal transection was carried out using a peng 's multifunctional operative dissector ( hangzhou shuyou medical instrument co. , ltd . , hangzhou , zhejiang , china ) along with ischemia line .
vascular clips or polypropylene sutures were used to control the divided vascular and biliary structures .
the specimen of the liver was retrieved and placed in a plastic bag after enlargement of one of the port sites .
all patients received prophylactic antibiotics immediately prior to the operation and had the same postoperative care by a professional nursing team .
postdischarge transhepatic arterial chemoembolization and other adjuvant therapies were recommended for patients diagnosed with hepatocellular carcinoma or other malignant tumors .
follow - up included physical examination , laboratory tests , tumor markers , and imaging examination every 3 months .
statistical analysis was performed using ibm spss statistics for windows , version 19.0 ( ibm corp . , armonk , ny , usa ) .
continuous variables were expressed as median ( range ) while categorical variables were expressed as number ( percentage ) .
whitney u - test while categorical variables were compared using the chi - square test or fisher 's exact test
prior to data collection , the study protocol was evaluated and approved by the ethical committees for human subjects at sir run run shaw hospital affiliated to medical college of zhejiang university .
three hundred and thirty - six patients who had undergone laparoscopic hepatectomy at our hospital from march 2012 to june 2015 were included in this retrospective study .
we divided these patients into two groups : an experimental group of those who had undergone previous upper abdominal surgery ( ps group , n = 42 ) and a control group of those who had not ( ns group , n = 294 ) .
previous upper abdominal surgery was defined as surgery performed above the umbilical region , including hepatobiliary and pancreatic surgery , splenectomy and gastrectomy , and surgery involving the small intestine , colon , kidney , and upper abdominal retroperitoneum . in this study ,
laparoscopic hepatectomy included malignant or benign primary hepatic tumors , metastatic hepatic carcinoma , and intrahepatic duct stones .
inclusion criteria were : ( 1 ) primary hepatic malignant tumors with no extrahepatic metastasis ; metastatic hepatic tumors that metastatic focuses were limited to one lobe of liver ; benign hepatic tumors that were obviously symptomatic , at high risk for rupture with life - threatening consequences , or with unclear diagnosis ; intrahepatic duct stones with obvious stricture or dilation of the bile duct and liver atrophy ; ( 2 ) child - pugh score a or b ; ( 3 ) well - preserved general condition .
patients with severe portal hypertension or american standards association ( american society of anesthesiologists )  grade iii or future liver remnant insufficiency ( < 30% in the nonsclerotic liver or < 40% in the liver with cirrhosis ) were excluded .
briefly , a 10 mm camera trocar was inserted subumbilically in the ns group and in where adhesions were expected to be minimal in the ps group .
pneumoperitoneum was established with carbon dioxide to a pressure of 1215 mmhg ( 1 mmhg = 0.133 kpa ) . under laparoscopic guidance ,
three more ports were established : a 10 mm main port in the xiphoid for surgical manipulation and two 5 mm accessory ports on the right side of the abdomen . for major liver resection ,
the hepatic hilum was dissected , and liver parenchymal transection was carried out using a peng 's multifunctional operative dissector ( hangzhou shuyou medical instrument co. , ltd . , hangzhou , zhejiang , china ) along with ischemia line .
vascular clips or polypropylene sutures were used to control the divided vascular and biliary structures .
the specimen of the liver was retrieved and placed in a plastic bag after enlargement of one of the port sites .
all patients received prophylactic antibiotics immediately prior to the operation and had the same postoperative care by a professional nursing team .
postdischarge transhepatic arterial chemoembolization and other adjuvant therapies were recommended for patients diagnosed with hepatocellular carcinoma or other malignant tumors .
follow - up included physical examination , laboratory tests , tumor markers , and imaging examination every 3 months .
statistical analysis was performed using ibm spss statistics for windows , version 19.0 ( ibm corp . , armonk , ny , usa ) .
continuous variables were expressed as median ( range ) while categorical variables were expressed as number ( percentage ) .
whitney u - test while categorical variables were compared using the chi - square test or fisher 's exact test
the cohort consisted of 336 patients divided into ps ( n = 42 ) and ns ( n = 294 ) groups .
the ps group was significantly older than the ns group ( 65 years [ 3880 years ] vs. 54 years [ 1685 years ] , p < 0.001 ) .
moreover , the alkaline phosphatase of patients in ps group was significantly higher than that in ns group ( 111 u / l [ 46551
there were no significant between - group differences in other demographic variables , including sex , presence of cirrhosis or hepatitis - b , and liver function .
characteristics and preoperative liver function of patients with laparoscopic hepatectomy * continuous data are presented as median ( range ) , mann 
whitney u - test ; categorical data are presented as n ( % ) , chi - square test .
akp : alkaline phosphatase ; alt : alanine aminotransferase ; ast : aspartate aminotransferase ; -gt : gamma - glutamyltransferase ; pt : prothrombin time ; tb : total bilirubin ; ps : previous upper abdominal surgery ; ns : nonprevious upper abdominal surgery ; alb : albumin .
there was no significant difference in median operative duration between the ps group and the ns group ( 180 min [ 50400 min ] vs. 160 min [ 25500 min ] , p = 0.869 ) .
median intraoperative blood loss was same between the ps group and the control group ( 200 ml [ 201500 ml ] vs. 200 ml [ 52000 ml ] , p = 0.907 ) . in the ps group
( n = 42 ) , six cases were converted to open surgery because of the presence of severe adhesions .
of 37 conversions to open procedure in the ns group ( n = 294 ) , 25 were because of severe adhesions , six because of bleeding , four because of inadequate margins , and two because of severe gas embolism .
the rate of intraoperative transfusion was identical between the two groups ( 14.3% vs. 14.3% , p = 1.000 ) .
with regard to the pringle maneuver , the ns group tended to have a shorter clamping time , but the difference was not significant ( 13 min [ 525 min ] vs. 15 min [ 1248 min ] , p = 0.294 ) .
the overall complication rate was significantly lower in the ns group than in the ps group ( 17.0% vs. 31.0% , p = 0.030 ) , but no between - group difference was observed in clavien - dindo grade .
the duration of postoperative hospital stay , the rate of unplanned re - admission within 3 months , and the postoperative liver function were similar between groups [ table 3 ] .
perioperative outcomes of patients with laparoscopic hepatectomy * continuous data are presented as median ( range ) , mann 
whitney u - test ; categorical data are presented as n ( % ) , chi - square test ; categorical data are presented as n ( % ) , fisher s test .
na : not available ; 3-month re - admisssions : unplanned re - admission within 3 months ; pm : pringle maneuver ; ps : previous upper abdominal surgery ; ns : nonprevious upper abdominal surgery .
liver function of patients with laparoscopic hepatectomy on postoperative day 1 data are presented as median ( range ) , mann 
akp : alkaline phosphatase ; alt : alanine aminotransferase ; ast : aspartate aminotransferase ; -gt : gamma - glutamyltransferase ; pt : prothrombin time ; tb : total bilirubin ; ps : previous upper abdominal surgery ; ns : nonprevious upper abdominal surgery ; alb : albumin . liver function of patients with laparoscopic hepatectomy on postoperative day 3 data are presented as median ( range ) , mann - whitney u - test .
akp : alkaline phosphatase ; alt : alanine aminotransferase ; ast : aspartate aminotransferase ; -gt : gamma - glutamyltransferase ; pt : prothrombin time ; tb : total bilirubin ; ps : previous upper abdominal surgery ; ns : nonprevious upper abdominal surgery ; alb : albumin .
the extent of liver resection did not differ significantly between the two groups [ table 5 ] .
the extension of liver resection of two groups had no differences significantly (  = 2.636 , p = 0.104 ) . in the ps group
, 13 left hemihepatectomies , and 4 right hemihepatectomies were performed . in the control group ,
of the 56 patients who underwent left hemihepatectomy , three underwent concomitant caudate lobe resection .
extent of liver resection of patients with laparoscopic hepatectomy hemi ( or greater ) hepatectomy was defined as major liver resection ; less than hemihepatectomy was defined as minor .
ps : previous upper abdominal surgery ; ns : nonprevious upper abdominal surgery . of the 336 patients in both groups , 111 ( 101 in the ns group and 10 in the ps group )
although the preoperative alpha - fetoprotein level was significantly higher in the ns group , the median maximum tumor diameters ( 2.7 cm [ 1.37.5 cm ] in the ps group and 4.0 cm [ 0.816.2 cm ] in the control group , p = 0.188 ) did not differ significantly between groups .
r0 resection was achieved in all patients except one , in the ns group , whose resection was r1 [ table 6 ] .
hcc - related outcomes of patients with laparoscopic hepatectomy * continuous data are presented as median ( range ) , mann 
whitney u - test ; categorical data are presented as n ( % ) , fisher s test .
na : not available ; rfa : radiofrequency ablation ; tace : transhepatic arterial chemoembolization .
one patient received tace and targeted radiotherapy ; hcc : hepatocellular carcinoma ; ps : previous upper abdominal surgery ; ns : nonprevious upper abdominal surgery ; afp : alpha - fetoprotein .
the ps group patients ( n = 42 ) were divided into two subgroups by type of previous surgery , laparoscopic ( n = 13 ) or open ( n = 29 ) .
there were no significant between - group differences in any perioperative outcome , including operative duration , intraoperative blood loss , and rates of transfusion and overall complications [ table 8 ] .
subgroup analysis of patients of previous upper abdominal surgery group by type of previous surgery subgroup analysis of patients with previous upper abdominal surgery * continuous data are presented as median ( range ) , mann 
whitney u - test ; categorical data are presented as n ( % ) , fisher s test .
na : not available ; 3-month readmissions : unplanned re - admission within 3 months ; pm : pringle maneuver .
the ps group patients ( n = 42 ) were divided into two subgroups by type of previous surgery , laparoscopic ( n = 13 ) or open ( n = 29 )
there were no significant between - group differences in any perioperative outcome , including operative duration , intraoperative blood loss , and rates of transfusion and overall complications [ table 8 ] .
subgroup analysis of patients of previous upper abdominal surgery group by type of previous surgery subgroup analysis of patients with previous upper abdominal surgery * continuous data are presented as median ( range ) , mann 
whitney u - test ; categorical data are presented as n ( % ) , fisher s test .
na : not available ; 3-month readmissions : unplanned re - admission within 3 months ; pm : pringle maneuver .
in the past , repeat surgery was considered as a contraindication for a laparoscopic procedure .
we believe there is an even greater challenge associated with any type of laparoscopic hepatobiliary surgery after previous upper abdominal surgery .
bleeding of vascular - rich adhesions can lead to poor visualization , and disruptions in the hilar structure and immobility of liver result in a prolonged operation and greater blood loss .
several groups have reported that the morbidity and mortality rates of open repeat liver resections vary from 22% to 28% and 0% to 5% , respectively .
as the innovation of laparoscopic technique , laparoscopic hepatectomy has the advantages of inducing less surgical trauma and resulting in a shorter recovery time and hospital stay . in theory , a laparoscopic procedure decreases the stress response and protects postoperative immunity , which are also benefits of a minimal incision and which correspond to the popular concept of rapid rehabilitation .
although , there have been some concerns about the ability of laparoscopic hepatectomy to cure malignancy
. however , cherqui et al . reported 93% 3-year survival in patients with peripheral hepatocellular carcinoma undergoing laparoscopic resection , with an acceptable 30% overall recurrence rate , and similar results were reported by sarpel et al .
moreover , many literature reviews have demonstrated no difference in the treatment of malignant tumors in terms of surgical margin between laparoscopic and open hepatectomy , and some experts even have suggested that laparoscopic left lateral lobe resection is now a standard procedure .
in this study , although the age of ps group was significantly older than that of ns group , there were no other significant between - group differences in short - term outcomes .
only overall complications were significantly higher in the ps group than in the ns group .
only two cases with gas embolism were reported in ns group . in the subgroup analysis ,
the type of previous surgery ( laparoscopy vs. laparotomy ) had no effect on short - term postoperative outcomes .
therefore , previous upper abdominal surgery is not the contraindication for a laparoscopic procedure as before , though many patients are still undergoing follow - up , and data on long - term outcomes of oncologic integrity are collected sequentially . in conclusion ,
laparoscopic hepatectomy in patients with previous upper abdominal surgery is controversial , and the ethical issues that would be associated with a randomized controlled trial prevent resolution of the issue in this manner .
however , it is gaining greater acceptance , and a number of retrospective studies support laparoscopic hepatectomy as a feasible and safe procedure for patients who have undergone previous upper abdominal surgery and regardless of whether the previous surgery was laparoscopic or open .
this study was supported by the grant from the fundamental research funds for the central universities ( no .
this study was supported by the grant from the fundamental research funds for the central universities ( no .
 background : laparoscopic liver resection has become an accepted treatment for liver tumors or intrahepatic bile duct stones , but its application in patients with previous upper abdominal surgery is controversial . 
 the aim of this study was to evaluate the feasibility and safety of laparoscopic hepatectomy in these patients.methods:three hundred and thirty - six patients who underwent laparoscopic hepatectomy at our hospital from march 2012 to june 2015 were enrolled in the retrospective study . 
 they were divided into two groups : those with previous upper abdominal surgery ( ps group , n = 42 ) and a control group with no previous upper abdominal surgery ( ns group , n = 294 ) . 
 short - term outcomes including operating time , blood loss , hospital stay , morbidity , and mortality were compared among the groups.results:there was no significant difference in median operative duration between the ps group and the ns group ( 180 min vs. 160 min , p = 0.869 ) . 
 median intraoperative blood loss was same between the ps group and the control group ( 200 ml vs. 200 ml , p = 0.907 ) . 
 the overall complication rate was significantly lower in the ns group than in the ps group ( 17.0% vs. 31.0% , p = 0.030 ) . 
 mortality and other short - term outcomes did not differ significantly between groups.conclusions:our study showed no significant difference between the ps group and ns group in term of short - term outcomes . 
 laparoscopic hepatectomy is a feasible and safe procedure for patients with previous upper abdominal surgery . 
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Patient selection
Surgical technique
Perioperative care and follow-up
Statistical analysis
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Subgroup analysis of clinical outcomes of patients in PS group
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Financial support and sponsorship
Conflicts of interest