Introduction

The choledochal cyst (QC) is a rare congenital disease characterized by dilation of the extrahepatic and/or intrahepatic bile ducts. This condition was first reported by Vater and Ezler in the year 1723 [1]. It is divided into five categories according to Todani, 1977 [2], which considers aspects such as biliary morphology and the anatomical distribution of bile duct cystic lesions inside and outside the liver [3].

Epidemiologically it is more frequent in Asian populations where it has a prevalence of one in every thousand live births compared to a rate of one in every hundred thousand live births in Western populations such as Europe and America. Although uncommon in Western populations, the incidence in the United States and Australia is 1 in 13,500 and 1 in 15,000 live births, respectively [4, 5].

Modern imaging techniques have facilitated the diagnosis of QC at any time from birth to adulthood [6]. The symptoms of QC include abdominal pain, jaundice, cholangitis and can eventually lead to malignant transformation, so early diagnosis and adequate surgical resection are very important. For many years, open resection, as a standard procedure, has had a great impact in the treatment of these cysts [7].

Historically, the treatment of QC included surgical resection. However, this optimally low approach has led to long-term complications, including biliary obstruction, jaundice, cholangitis, and frequently requiring additional surgery [8]. Laparoscopic excision (LE) is one of the ways to operate on a critically ill patient for KC, which has many benefits, including minimal scarring and sharp, magnified images that can facilitate dissection. Compared with open excision (EA), the benefits of EL are well documented [9].

Antonacci et al., 2014, in Italy, were commissioned to carry out a systematic review using data from Medline, Embase, Ovid and Cochrane to identify the surgical management of hepatic cysts without signal whose treatment is given by EL and EA to determine the results after short and long term of the associated treatments, divided in three time periods. As results, it was observed that, in the three periods analyzed, EL showed a statistically significant reduction in operating time (p=0.009) and hospital stay (p=0.001) and a significant reduction (p<0.05) in relapses. symptomatic in patients with polycystic liver disease (25%) compared with simple liver cysts (8%). In conclusion, it was suggested that EL may be the treatment of choice in patients with symptomatic non-parasitic liver cysts, providing the short-term benefit of minimally invasive surgery [10].

Zhen et al., 2015, in China, conducted a systematic review where they compared EA with EL in the treatment of QC and then determine if EL is safe and valid. Data sources were Medline, Ovid, Elsevier, Google Scholar, Embase, and Cochrane Library. Only comparative cohort studies were included, collecting the following information: study characteristics, quality, outcome data, among others. The results showed that, although the individuals in the EL group had a longer surgical time (MD=56.6; 95% CI: 32.2 to 80.9; p=0.00001), EL had a shorter duration. of hospitalization time (MD=–1.9; 95% CI: –2.5 to –1.4; p=0.00001) and showed recovery of bowel function (MD=–0.9; CI: 95%=–1.3 to –0.5, p=0.00001). The study concluded that, compared to AS, EL is a safe, valid, and viable alternative [11].

Shen et al., 2015, in China, compared the safety and efficacy between EL and EA in children with KC using a meta-analysis. As inclusive criteria for data collection, databases such as PubMed, Embase, Science Citation Index and Cochrane Library were identified to analyze five variables. In the EL group compared to the EA group, the operative time was longer (MD=59.1; 95% CI: 27.6 to 90.6; p=0.0002), while the postoperative hospitalization time was lower (MD=–2.0; 95% CI: –2.5 to –1.5, p<0.00001), intraoperative blood loss was lower (MD=–37.1, CI:95%: –66.7 to –7.6, p=0.01) and the time elapsed until food intake was shorter (MD=–1.1, CI:95% –1.6 to –0.7, p=0.01). The postoperative morbidity rate was higher in the AS group, but there is no statistically significant difference between the two groups in postoperative morbidity (OR=0.5, 95% CI 0.1 to 2.1, p=0.35). The study concluded that EL is a feasible and safe treatment with less postoperative morbidity, shorter hospital stay, and less blood loss than EA [12].

Sokouti et al, 2017, in Iran, conducted a systematic review and meta-analysis where they analyzed the advantages and disadvantages of EA and EL, given the results of hepatic hydatid cysts. The Pubmed and Scopus databases were used for articles published between January 2000 and December 2016. The random effects models of the results of the two procedures were OR=0.85, LL=0.47, UL=1, 55, Z=–0.53, p=0.60 for postoperative complications; OR=0.85, LL=0.14, UL=5.11, Z=–0.18, p=0.86 for mortality; and OR=0.46, LL=0.13, UL=1.64, Z=–1.20, p=0.23 for cure rate. The results did not show a promising trend for the benefits of EA and EL in the treatment of hepatocystic cysts. However, the informative measures to compare these surgeries can be calculated from the three variables mentioned [13].

Sun et al, 2020, in China, conducted a systematic review and meta-analysis to better understand the efficacy and safety of EL in children with KC compared to AD. The search was performed in PubMed, Embase, Cochrane Central Register, and ClinicalTrials. The results found no significant differences in short-term postoperative complications (RR=–1.1; CI: 95%=–1.7 to –0.7) between the two methods. However, if there was significance in the long-term improvements (RR=0.09; CI: 95%=0.01 to 0.2) and total postoperative complications (RR=–0.3; CI: 95%=–0.4 to –0.2). It was concluded that EL produces similar or even better postoperative results compared to EA for children with QC [14].

A. Mego, 2016 in Lima, determined the effectiveness of EL versus EA in the recovery of the patient operated on for appendicitis through a retrospective and observational systematic review, performing a search where it was limited to full-text articles and the selected articles were critically read. to identify its level of evidence. In the results it was possible to demonstrate that EL has many advantages in the recovery of the patient in 66% of the cases. With small incisions, the patient heals faster, with less pain and a shorter period of disability, can quickly return to normal activities, can walk, go up and down stairs, leave the hospital spontaneously immediately after surgery [15].

C. Yépez, 2016 established the existence of a significant difference between the frequency of surgical complications of EL versus AS in pregnant women with acute appendicitis in a hospital in Trujillo, La Libertad. For this purpose, 78 clinical histories were reviewed, being classified in the EL group (n=26) and in the EA group (n=52), taking into account the Chi Square test to establish the differences. In the results, no significant differences were found in postoperative complications between both surgical techniques, with the exception of the frequency of threatened abortion early in the third trimester (p=0.007) [16].

W. Berrocal, 2018, carried out a study comparing the complications of LE and AS in complicated acute appendicitis in patients under 14 years of age in a hospital in Lima, for which the medical records of 201 patients with complicated acute appendicitis were reviewed., operated by EL and 160 patients who were operated on by EA. In the results obtained, there was no significant difference in the complications of AS and EL (p=0.493). Incisional infection occurs more frequently in AS (p=0.004) and postoperative intestinal obstruction more frequently in EL (p=0.035). In addition, there were no statistical differences in the residual abscess, age, sex, age group and hospitalization time (p<0.05) [17].

Cornejo-Carrasco & Carrasco-Rivera, 2020, compared the economic and clinical results of EL and EA in the treatment of hydatid cysts of the liver in a hospital in Lima. The medical records of all adult patients undergoing AS and EL were reviewed, where eight variables were evaluated. There was no difference in surgical time or surgical complications, postoperative morbidity rates were 27% in the EA group and 31% in the EL group. Less postoperative pain, shorter hospital stay, and shorter medical rest were shown for EL (p<0.05) [18].

Panduro-Correa et al., 2020, evaluated the clinical and surgical characteristics, postoperative complications, and survival in patients with advanced gastric cancer using EA compared to EL in a Lima hospital. In the results it was observed that AD represented a risk factor in patients suffering from metastases (OR=5.7; CI: 95%=1.6 to 30.9), ascites (OR=5.3; CI: 95%=3.3 to 8.5), comorbidities in general (OR=2.9; CI: 95%=1.9 to 4.6), post-surgical complications in general (OR=3.9; CI: 95%=2.5 to 6.1) and present relapse (OR=3.7; CI: 95%=2.3 to 6.2). The study concluded that EL had fewer postoperative complications compared to AS [19].

Laparoscopy has made it possible to perform minimally invasive interventions, establish both macroscopic and microscopic diagnoses by taking samples to extract tissue in search of disease [20]. Currently, laparoscopic abdominal surgery has made it possible to carry out everything from appendectomy or cholecystectomy to extensive resection of the small and large intestine [21]. For years, the standard treatment for diseases was surgical through the open procedure, however, the rate of complications, discomfort after the operation, and the requirements for hospital stay and recovery days, among others, have made many surgeons in the world opt for methods that provide minimal invasion [22—24].

Methods

Types and research design

This study is a systematic review, with the objective of evaluating the published studies that compared laparoscopic excision versus conventional open in patients with choledochal cysts. This review was reported according to the reference items for systematic reviews and meta-analyses (PRISMA-2020).

Data source

Pubmed, Scopus, Web of Science and EMBASE are the bibliographic databases in which the search was carried out. Searches were performed from to May 14, 2022, and included key phrases, MESH (Pubmed), and Emtree thesauri (Scopus, Embase). Finally, for each database, a search strategy was applied. («Laparoscopic») AND («open cholecystectomy»). There were no limitations regarding language or date of publication. In addition, all reference lists of relevant studies and included review articles were handsearched to find other potentially eligible trials. Pre-print services such as «medrxiv» and Google Scholar will be used to examine the gray literature.

Eligibility criteria

All those works that met the following criteria were included: 1) Observational studies (cohort or case control); 2) adult patients with choledochal cysts; 3) studies comparing laparoscopic versus conventional open excision or surgery. The following types of studies were not considered: conference abstracts, case reports and series, systematic reviews, narrative reviews, letters to the editor.

Selection of studies

The authors carried out the first selection phase, evaluating the titles and abstracts after the electronic searches, applying the inclusion and exclusion criteria for each evaluated result. In addition, all titles and abstracts from the electronic search were downloaded into EndNote 20 software and duplicate records were removed. After this phase, the full texts of the selected studies were searched, and they were evaluated taking into account the inclusion criteria and justifying the reasons for exclusion. The included studies were part of the systematic review and data extraction was carried out. The presence of any disagreements was resolved by consulting a third review author (JJB).

Outcomes

The primary outcome was general complications. Secondary outcomes are operating time (min) and postoperative hospitalization time (days).

Data extraction

Two authors independently extracted the information from each study, using a previously prepared Excel spreadsheet form. Again, discrepancies were consulted with another author (JJB). The following data were extracted from each study: authors, year of publication, country, type of study, number of participants per intervention arm, selection criteria, description of the intervention and control, primary and secondary results.

Risk of bias analysis

Two investigators independently assessed risk of bias using the Newcastle Ottawa Scale (NOS) tool. Disagreements were resolved by discussion with a third investigator (JJB). The NOS by domain and study will be described as low and high.

Analysis plan

The present work carried out a meta-analysis study, in which the random effects model and inverse variance method were executed. For continuous outcomes, mean difference (MD) with 95% confidence intervals (95% CI) was used, while for dichotomous outcomes, relative risk (RR) with 95% CI were assessed. Statistical heterogeneity of effects between studies was assessed using the I2 index, with values corresponding to low (<30%), medium (30—60%) and high (>60%) levels of heterogeneity. In the sensitivity analysis, the inverse method applied in the meta-analysis was considered. Therefore, for binary analysis the fixed effects model was used, and with respect to the methods, the Mantel-Haenzel method was used. While, for the continuous analysis, the inverse variance method was used.

Ethical aspects

Due to the fact that this study is of a secondary nature, it is expected to have the corresponding exoneration from the Ethics and Research Committee of the Antenor Orrego Private University as it does not consider a vulnerable population.

Results

A total of 364 articles were identified, of which 69 duplicates were eliminated. Of the remaining 295 articles, a selection was made according to the title and objectives, eliminating 284 articles that did not meet the eligibility criteria. Of the 11 remaining articles, the full texts were retrieved, eliminating four studies, with only seven studies included in the systematic review (shown in fig. 1). Of the five included studies, two were conducted in China, Canada, and Vietnam. All studies were retrospective cohorts. The characteristics of the included participants (n=1269) were patients with choledochal cysts, and one study reported patients with biliary atresia. The mean age of the participants was 59.1 years (SD 13.6). The evaluated outcomes were major complications, postoperative hospital stay, and operating time. All studies concluded that laparoscopic excision was effective compared to open surgery (shown in table).

Fig. 1. PRISMA flow chart.

Characteristics of the studies included in the review

Note. CL: laparoscopic excision; OC: Open Excision.

Effect of laparoscopic excision on the outcomes evaluated

In the reported data, it was found that laparoscopic excision does not reduce major complications (pneumonia or sepsis), compared with open excision (RR 0.88; 95% CI 0.42—1.84; p=0.6; I2=15%; shown in fig. 2). Laparoscopic excision is significantly longer in terms of operating time (min), compared to open excision (MD 56.57; 95% CI 32.20—80.93; p=0.0001; I2=0%; shown in fig. 3). Laparoscopic excision significantly reduces the length of postoperative hospital stay (days) compared with open excision (MD –1.59; 95% CI –2.45 to –0.73; p=0.0003; I2=77%; shown in fig. 4).

Fig. 2. Effect of laparoscopic excision versus open excision on major complications.

Fig. 3. Effect of laparoscopic excision versus open excision on operating time (min).

Fig. 4. Effect of laparoscopic excision versus open excision on postoperative hospital stay (days).

Risk of bias analysis

Six studies with high risk of bias were found, of which all six had a high risk of bias in selection, comparability, and outcome assignment (shown in fig. 5).

Fig. 5. Risk of bias analysis.

Discussion

This systematic review has explored randomized controlled trials of laparoscopic excision versus open surgery. It was mainly found that there is no efficacy in terms of major complications such as bleeding and sepsis, but a reduction in hospital stays and an increase in operating time were found.

The benefits of laparoscopic excision include less pain after surgery, shorter hospital stay, quicker return to usual activities, and better cosmetic outcome, although our findings have occasionally found a significant effect in only one of the outcomes evaluated.

The open method was associated with a shorter operating time, while the laparoscopic approach was associated with a shorter hospital stay after surgery. For many years, laparoscopic excision has been the «gold standard» in the treatment of symptomatic gallstones. The open excision is considered almost a relic of the past, used only when laparoscopic treatment fails and conversion is required. This mentality has carried over to the treatment of choledochal cysts. Often, patients are treated conservatively and referred to a laparoscopic surgeon for delayed cholecystectomy, rather than undergoing open cholecystectomy to resolve the condition during the acute period.

The choledochal cyst (QC) is a rare congenital disease characterized by dilation of the extrahepatic and/or intrahepatic bile ducts. This condition was first reported by Vater and Ezler in the year 1723 [1].

This systematic review studied whether laparoscopic excision is more effective than open excision in the treatment of choledochal cysts, the first one presented lower risk in the intervention of said pathology and the second presented a greater range of risk and ineffectiveness in the treatment of choledochal cysts. intervention of this pathology, in relation to the studies analyzed.

Another finding that was considered is the operating time, according to the studies included in relation to laparoscopic excision and open excision, they have a similar time range, the first of them uses a maximum of 11 hours 20 minutes and a minimum of 51 minutes; while in the second one a maximum of 11 hours 20 minutes and a minimum of 35.4 minutes are used.

In the present study, the research of other authors was considered, such as Antonacci et al., 2014 in Italy, who were in charge of carrying out a systematic review using data from Medline, Embase, Ovid and Cochrane to identify the surgical management of liver cysts without signal whose treatment is given by EL and EA to determine the short and long-term results of associated treatments, divided into three periods of time, it was concluded that EL may be the treatment of choice in patients with symptomatic non-parasitic liver cysts, providing the short-term benefit of minimally invasive surgery [10].

To carry out the following analysis, three studies were considered to determine the hospitalization time in laparoscopic excision and in open excision, where it could be observed that in the first one less time is used since a maximum of 74 days and a minimum of 5 days; while in the second, a maximum of 146 days and a minimum of 7 days are considered.

To contrast the previously detailed result, the study carried out by Zhen et al., 2015, in China, was taken into account, who carried out a systematic review where they compared EA with EL in the treatment of QC and then determined if EL is safe and valid. EL had a shorter duration of hospitalization time and showed recovery of bowel function. The study concluded that, compared to AS, EL is a safe, valid, and viable alternative [11].

In relation to the analysis on the degree of intraoperative blood loss in laparoscopic excision and open excision in the treatment of choledochal cysts, where there was also a considerable difference since in the first the quantity in maximum milliliters is 22.9 and at least is 3.28; while in the second, the maximum number of milliliters is 52.7 and the minimum is 1.13, considering the age of the patients.

According to the result found above, in a study conducted by Shen et al., 2015, in the EL group compared to the EA group, the intraoperative blood loss in EL was lower than in EA, being EL a procedure safer and more feasible.

To calculate the degree of bile leakage in laparoscopic excision and open excision in the treatment of choledochal cysts, it was possible to analyze that in the first it is a maximum of 2% and a minimum of 1% in consideration of the age of the patient. patient, and in the second maximum it is 4% without considering a minimum, in this case in patients ranging between 42.4 and 34.2 years.

Since the degree of bile leakage is a complication at the time of the operation, we consider the study by C. Yépez, 2016, who established the existence of a significant difference between the frequency of surgical complications of LE versus AS in pregnant women with acute appendicitis in Trujillo hospital, La Libertad. For this purpose, 78 clinical histories were reviewed, being classified in the EL group (n=26) and in the EA group (n=52), taking into account the Chi Square test to establish the differences. In the results, no significant differences were found in postoperative complications between both surgical techniques, with the exception of the frequency of threatened abortion early in the third trimester (p=0.007) [16].

When analyzing the level of postoperative complications in laparoscopic excision and in open excision in the treatment of choledochal cysts, two articles were considered in which it could be identified that both authors consider various complications, such as adhesive ileus, obstruction of the gallbladder, cholangitis and reoperation that in this case Canción et al, (2017) assert that they occur in most cases when open excision is applied. While Xiaolong et al, (2019) assert that the highest rate of complications occurs in open excision such as respiratory tract infection, residual cysts, gallstones, pancreatitis, intestinal obstruction, hepaticojejunostomy stenosis, unlike the reoperation in which he considers arises when laparoscopic excision is applied.

Within this study we must emphasize the intervention carried out by other researchers, where we can cite Sun et al, 2020, in China, they carried out a systematic review and a meta-analysis to better understand the efficacy and safety of EL in children with KC compared to the EA. The search was carried out in PubMed, Embase, Cochrane Central Register and ClinicalTrials, concluding that EL produces similar or even better postoperative results compared to EA for children with KC [14].

Regarding the degree of morbidity and mortality, the study by Xiaolong et al, (2019) was considered, who mentions that both laparoscopic excision and open excision have a morbidity rate of 20%, while in the first It presents 0 possibilities of mortality, unlike the second, which in a study carried out on 60 patients, 3.3% died.

Shen et al, 2015, in China, compared the safety and efficacy between LE and EA in children with KC using a meta-analysis, where the postoperative morbidity rate was higher in the EA group, but there is no statistically significant difference. between the two groups in postoperative morbidity, therefore it was concluded that EL is a feasible and safe treatment with less postoperative morbidity, shorter hospital stay and less blood loss than AS [12].

In relation to the limitations that could be found in the development of this research is that despite the fact that there is a large number of studies related to the subject, they do not have open access for the reader; likewise, not many studies related to open excision were found, since laparoscopic excision is a new technique, it attracts more attention thanks to its optimal results.

Conclusion

Laparoscopic excision does not reduce major complications compared with open surgery in patients with choledochal cysts. Laparoscopic excision increases operating time compared with open surgery in patients with choledochal cysts. Laparoscopic excision reduces the length of postoperative hospital stay compared with open surgery in patients with choledochal cysts.

Statements

Acknowledgement

All authors certify that they meet the current International Committee of Medical Journal Editors (ICMJE) criteria for authorship.

Conflict of Interest statement

The authors have no conflicts of interest to declare

Funding sources

The authors declare that this work did not receive any grants from funding agencies in the public, commercial, or nonprofit sectors.

Author contributions

Plasencia G and Caballero J: Conceptualization, Formal analysis, Research, Methodology, resources, Software, Validation, Visualization, Writing.

Zavaleta C and Plasencia W: Writing — review and editing, Conceptualization, Formal analysis.