Depressed cytotoxic activity of hepatic nonparenchymal cells in rats with obstructive jaundice

The impact of preoperative biliary drainage on postoperative healthcare-associated infections and clinical outcomes following pancreaticoduodenectomy: a ten-year retrospective analysis

BACKGROUND

Pancreaticoduodenectomy (PD) is a complex procedure and easily accompanied by healthcare-associated infections (HAIs). This study aimed to assess the impact of PBD on postoperative infections and clinical outcomes in PD patients.

METHODS

The retrospective cohort study were conducted in a tertiary hospital from January 2013 to December 2022. Clinical and epidemiological data were collected from HAIs surveillance system and analyzed.

RESULTS

Among 2842 patients who underwent PD, 247 (8.7%) were diagnosed with HAIs, with surgical site infection being the most frequent type (n = 177, 71.7%). A total of 369 pathogenic strains were detected, with Klebsiella pneumoniae having the highest proportion, followed by Enterococcu and Escherichia coli. Although no significant association were observed generally between PBD and postoperative HAIs, subgroup analysis revealed that PBD was associated with postoperative HAIs in patients undergoing robotic PD (aRR = 2.174; 95% CI:1.011-4.674; P = 0.047). Prolonging the interval between PBD and PD could reduce postoperative HAIs in patients with cholangiocarcinoma (≥4 week: aRR = 0.292, 95% CI 0.100-0.853; P = 0.024) and robotic PD (≤2 week: aRR = 3.058, 95% CI 1.178-7.940; P = 0.022). PBD was also found to increase transfer of patients to ICU (aRR = 1.351; 95% CI 1.119-1.632; P = 0.002), extended length of stay (P < 0.001) and postoperative length of stay (P = 0.004).

CONCLUSION

PBD does not exhibit a significant association with postoperative HAIs or other outcomes. However, the implementation of robotic PD, along with a suitable extension of the interval between PBD and PD, appear to confer advantages concerning patients' physiological recuperation. These observations suggest potential strategies that may contribute to enhanced patient outcomes.

Short-term preoperative drainage is associated with improved postoperative outcomes compared to that of long-term biliary drainage in pancreatic surgery

Purpose

The treatment of choice for patients presenting with obstructive cholestasis due to periampullary carcinoma is oncologic resection without preoperative biliary drainage (PBD). However, resection without PBD becomes virtually impossible in patients with obstructive cholangitis or severely impaired liver cell function. The appropriate duration of drainage by PBD has not yet been defined for these patients.

Methods

A retrospective analysis was conducted on 170 patients scheduled for pancreatic resection following biliary drainage between January 2012 and June 2018 at the University Hospital Dresden in Germany. All patients were deemed eligible for inclusion, regardless of the underlying disease entity. The primary endpoint analysis was defined as the overall morbidity (according to the Clavien-Dindo classification). Secondary endpoints were the in-hospital mortality and malignancy adjusted overall and recurrence-free survival rates.

Results

A total of 170 patients were included, of which 45 (26.5%) and 125 (73.5%) were assigned to the short-term (< 4 weeks) and long-term (≥ 4 weeks) preoperative drainage groups, respectively.

Surgical complications (Clavien-Dindo classification > 2) occurred in 80 (47.1%) patients, with significantly fewer complications observed in the short-term drainage group (31.1% vs. 52%; p = 0.02). We found that long-term preoperative drainage (unadjusted OR, 3.386; 95% CI, 1.507–7.606; p < 0.01) and periampullary carcinoma (unadjusted OR, 5.519; 95% CI, 1.722–17.685; p-value < 0.01) were independent risk factors for postoperative morbidity, based on the results of a multivariate regression model. The adjusted overall and recurrence-free survival did not differ between the groups (p = 0.12).

Conclusion

PBD in patients scheduled for pancreatic surgery is associated with substantial perioperative morbidity. Our results indicate that patients who have undergone PBD should be operated on within 4 weeks after drainage.

Mesenchymal stem cells suppress hepatic fibrosis accompanied by expanded intrahepatic natural killer cells in rat fibrosis model

Natural killer (NK) cells have antifibrotic effects. We have evaluated the influence of rat bone marrow-mesenchymal stem cell (BM-MSC) treatment on liver histology, biochemical liver function tests, systemic immunoregulatory state and NK cell distribution in liver and peripheral blood in rat model of common bile duct (CBD) ligation and compared the results with the control group. Rats were divided into three groups: (1) CBD ligated (CBDL) rats received phosphate-buffered saline (CBDL + PBS group) or (2) MSC (CBDL + MSC group) and sham-operated rats received MSC (healthy + MSC group). We found significantly decreased fibrosis scores with BM-MSC treatment in CBDL rats compared to the control (CBDL + PBS) group while no fibrosis developed in sham operated (healthy + MSC) group. BM-MSC treatment has decreased the inflammation as reflected by the significantly decreased T cell proliferation and inflammatory cytokine concentrations from splenocyte culture and liver tissue itself compared to CBDL + PBS. NK cells both in parenchyme and portal areas decreased significantly in liver and blood in CBDL + PBS compared to healthy + MSC while they were found to be increased in CBDL + MSC compared to CBDL + PBS rats. In conclusion, BM-MSCs may suppress hepatic fibrosis accompanied by expanded intrahepatic NK cells in CBDL rats. Thus, our animal study shows that MSC treatment holds great promise for treatment of patients with end-stage liver diseases through a possible mechanism by adopting the NK cell population and new studies investigating the role of NK cells and clinical fibrosis are warranted.Trial registration number: Marmara University Animal Care and Use Committee approval code: 73.2013.mar.

Role of immune cells in pancreatic cancer from bench to clinical application: An updated review

BACKGROUND

Pancreatic cancer (PC) remains difficult to treat, despite the recent advances in various anticancer therapies. Immuno-inflammatory response is considered to be a major risk factor for the development of PC in addition to a combination of genetic background and environmental factors. Although patients with PC exhibit evidence of systemic immune dysfunction, the PC microenvironment is replete with immune cells.

METHODS

We searched PubMed for all relevant English language articles published up to March 2016. They included clinical trials, experimental studies, observational studies, and reviews. Trials enrolled at Clinical trial.gov were also searched.

RESULTS

PC induces an immunosuppressive microenvironment, and intratumoral activation of immunity in PC is attenuated by inhibitory signals that limit immune effector function. Multiple types of immune responses can promote an immunosuppressive microenvironment; key regulators of the host tumor immune response are dendritic cells, natural killer cells, macrophages, myeloid derived suppressor cells, and T cells. The function of these immune cells in PC is also influenced by chemotherapeutic agents and the components in tumor microenvironment such as pancreatic stellate cells. Immunotherapy of PC employs monoclonal antibodies/effector cells generated in vitro or vaccination to stimulate antitumor response. Immune therapy in PC has failed to improve overall survival; however, combination therapies comprising immune checkpoint inhibitors and vaccines have been attempted to increase the response.

CONCLUSION

A number of studies have begun to elucidate the roles of immune cell subtypes and their capacity to function or dysfunction in the tumor microenvironment of PC. It will not be long before immune therapy for PC becomes a clinical reality.

Association of Preoperative Biliary Drainage with Postoperative Morbidity after Pancreaticoduodenectomy

Background. The advantages or disadvantages of preoperative biliary drainage (PBD) prior to pancreaticoduodenectomy (PD) remain unclear. Methods. A prospectively maintained database was queried for 335 consecutive patients undergoing standard PD surgery between 2009 and 2013. Clinical data and postoperative complications of the 47 patients receiving PBD and 288 patients with early surgery were compared. A matching analysis was also performed between patients receiving or not receiving PBD (no-PBD). Results. The indication for PBD was severe obstructive jaundice (81%) and cholangitis (26%) at the time of PBD. 47 PBD patients had higher bilirubin level than 288 no-PBD patients preoperatively (363.2 μmol/L versus 136.0 μmol/L, p < 0.001). Although no significant difference of any complications could be observed between the two groups, positive intraoperative bile culture and wound infection seemed to be moderately increased in PBD compared to no-PBD patients (p = 0.084 and 0.183, resp.). In the matched-pair comparison, the incidence of wound infection was three times higher in PBD than no-PBD patients (14.9% versus 4.3%, p = 0.080). Conclusions. PBD seems to moderately increase the risk of postoperative wound and bile duct infection. Therefore, PBD should be selectively performed prior to PD.

Effect of Preoperative Biliary Drainage on Complications Following Pancreatoduodenectomy: A Meta-Analysis

Preoperative biliary drainage (PBD) prior to pancreatoduodenectomy (PD) is still controversial; therefore, the aim of this study was to examine the impact of PBD on complications following PD. A meta-analysis was carried out for all relevant randomized controlled trials (RCTs), prospective and retrospective studies published from inception to March 2015 that compared PBD and non-PBD (immediate surgery) for the development of postoperative complications in PD patients. Pooled odds ratio (OR) and 95% confidence interval (CI) were estimated using fixed-effect analyses, or random-effects analyses if there was statistically significant heterogeneity (P < 0.05). Eight RCTs, 13 prospective studies, 20 retrospective studies, and 3 Chinese local retrospective studies with 6286 patients were included in this study. In a pooled analysis, there were no significant differences between PBD and non-PBD group in the risks of mortality, morbidity, intra-abdominal abscess, sepsis, hemorrhage, pancreatic leakage, and biliary leakage. However, subgroup analysis of RCTs yielded a trend toward reduced risk of morbidity in PBD group (OR 0.48, CI 0.24 to 0.97; P = 0.04). Compared with non-PBD, PBD was associated with significant increase in the risk of infectious complication (OR 1.52, CI 1.07 to 2.17; P = 0.02), wound infection (OR 2.09, CI 1.39 to 3.13; P = 0.0004), and delayed gastric emptying (DGE) (OR 1.37, CI 1.08 to 1.73; P = 0.009). This meta-analysis suggests that biliary drainage before PD increased postoperative infectious complication, wound infection, and DGE. In light of the results of the study, PBD probably should not be routinely carried out in PD patients.

Preoperative bile replacement improves immune function for jaundiced patients treated with external biliary drainage

BACKGROUND

Although preoperative biliary drainage in jaundiced patients is controversial, external biliary drainage (EBD) is beneficial for infection control in patients with biliary cancers. When EBD is performed, additional bile replacement (BR) has the benefit of improving impaired intestinal barrier function, but the detailed mechanism remains unknown. We examined the effect of bile replacement on immune functions over the duration of BR in jaundiced patients.

METHODS

Fifteen patients were enrolled into this prospective study. BR was started soon after the total serum bilirubin concentration reached 5.0 mg/dl and was continued for 14 days. Drained bile was given two times orally (2 × 100 ml/day). Concanavalin A (Con A)- and phytohemagglutinin (PHA)-stimulated lymphocyte proliferation and serum diamine oxidase (DAO) activity were measured before starting and during BR. Twenty patients with EBD and no BR were analyzed as a control group.

RESULTS

Serum liver enzymes, prothrombin time-international normalized ratio (PT-INR), and responses to Con A and PHA gradually improved over the 14 days of BR, but percentages of lymphocytes and DAO levels did not. PT-INR, and Con A and PHA responses did not improve during EBD in the control group. PT-INR significantly decreased in patients with a greater fraction of their drained bile replaced.

CONCLUSIONS

Our results indicate that preoperative BR using as large a quantity of bile as possible is useful for improving blood coagulability and cellular immunity in patients with EBD.

The current status of preoperative biliary drainage for patients who receive pancreaticoduodenectomy for periampullary carcinoma: a comprehensive review

BACKGROUND

Surgery on patients with malignant obstructive jaundice carries increased risks of postoperative morbidity and mortality. Preoperative biliary drainage has been developed to reduce this procedure-related risks, but its role in patients who are going to receive pancreaticoduodenectomy for periampullary carcinoma is still controversial.

METHODS

This article aimed at reviewing the current status of preoperative biliary drainage for patients with peri-ampullary tumors who were candidates for pancreaticoduodenectomy. A MEDLINE and PubMed database search from 1980 to 2013 was performed to identify relevant articles using the keywords "pancreaticoduodenectomy", "preoperative biliary drainage", "jaundice", "peri-ampullary neoplasm" and "carcinoma of pancreas". Additional papers were identified by a manual search of the references from the key articles.

RESULTS

There were six randomized controlled trials (RCTs) and 5 meta-analyses on preoperative biliary drainage for patients with malignant obstructive jaundice. Most of the results of these studies could not be used to define the role of preoperative biliary drainage for patients who received pancreaticoduodenectomy for periampullary carcinoma because: first, the majority of these studies were on bypass or palliative resections; second, various pathologies with both proximal and distal biliary obstruction were included; third, there were different forms of percutaneous or endoscopic drainage procedures; fourth, there were different durations of preoperative drainage; and finally, there were variations in the definition of events and outcomes. There was only one RCT which included a homogeneous group of patients with carcinoma of pancreas who underwent pancreaticoduodenectomy. For patients with periampullary tumor, the RCTS and meta-analyses showed no benefit of preoperative biliary drainage. Instead, there were some concerns about the drainage-related complications and the increase in positive intraoperative bile culture rate and the associated infective complication rate postoperatively.

CONCLUSION

Routine preoperative biliary drainage showed no beneficial effect on the surgical outcome for patients with periampullary tumor. A selective approach of preoperative biliary drainage should be adopted for these patients. The optimal duration and modality of preoperative biliary drainage remain unclear.

The optimal duration of preoperative biliary drainage for periampullary tumors that cause severe obstructive jaundice

BACKGROUND

Despite routine preoperative biliary drainage (PBD) with periampullary cancer, its optimal duration has not been established. The objective of this study was to investigate PBD in severely jaundiced patients.

METHODS

A total of 120 patients with periampullary tumors who underwent surgery with intent to cure after PBD for severe obstructive jaundice were enrolled. According to the duration of PBD, 66 and 54 patients were classified into the long-term (≥2 weeks) and short-term (<2 weeks) groups.

RESULTS

PBD-related complications occurred in 6 (9.1%) and 14 (25.9%) patients in the short-term and long-term groups, respectively (P = .014). Rates of surgery-related complications and mortalities were not significantly different between the 2 groups. The R0 resection rate tended to be lower (P = .054) and the mean length of hospital stay was significantly longer (P = .039) in the long-term group.

CONCLUSIONS

PBD duration <2 weeks is more appropriate in severely jaundiced patients with periampullary cancer.

Immunosuppression in the livers of mice with obstructive jaundice participates in their susceptibility to bacterial infection and tumor metastasis

Although patients with obstructive jaundice are susceptible to bacterial infections and cancers, the mechanisms remain to be elucidated. In the present study, liver mononuclear cells (MNCs) of bile duct-ligated (BDL) mice were immunologically assessed. Liver natural killer T cells were greatly decreased within 24 h after BDL. Upon injection of Escherichia coli (E. coli; 10 colony-forming units) at 7 days after the procedure, all BDL mice had died, but no sham mice died. Consistently, an overgrowth of E. coli was seen in the livers of BDL mice. Although the serum IL-12 and IL-18 levels after E. coli challenge in BDL mice were higher than those in sham mice, the IFN-gamma level was greatly suppressed. However, exogenous IFN-gamma injection significantly increased BDL mouse survival after E. coli challenge. Furthermore, liver MNC of BDL mice exhibited a lower cytotoxic activity against tumors, and BDL mice intravenously injected with liver metastatic EL-4 cells showed markedly increased EL-4 metastases. The total bile acids, as well as the bile acid fractions, increased in the sera and liver. IFN-gamma production by liver MNC from normal mice stimulated with LPS in vitro was inhibited by the addition of bile acids, whereas, conversely, the production of IL-12 and IL-18 increased. In conclusion, liver natural killer T cells were diminished in BDL mice, and the function of liver MNC (IFN-gamma production) was also impaired presumably due to increased bile acids. This may partly explain the increased susceptibility of BDL mice to bacterial infections and tumor metastasis.

Preoperative biliary drainage in patients with obstructive jaundice: history and current status

RATIONALE

Preoperative biliary drainage (PBD) has been introduced to improve outcome after surgery in patients suffering from obstructive jaundice due to a potentially resectable proximal or distal bile duct/pancreatic head lesion. In experimental models, PBD is almost exclusively associated with beneficial results: improved liver function and nutritional status; reduction of systemic endotoxemia; cytokine release; and, as a result, an improved immune response. Mortality was significantly reduced in these animal models. Human studies show conflicting results.

FINDINGS

For distal obstruction, currently the "best-evidence" available clearly shows that routine PBD does not yield the appreciated improvement in postoperative morbidity and mortality in patients undergoing resection. Moreover, PBD harbors its own complications. However, most of the available data are outdated or suffer from methodological deficits.

CONCLUSION

The highest level of evidence for PBD to be performed in proximal obstruction, as well as over the preferred mode, is lacking but, nevertheless, assimilated in the treatment algorithm for many centers. Logistics and waiting lists, although sometimes inevitable, could be factors that might influence the decision to opt for PBD, as well as an extended diagnostic workup with laparoscopy (on indication) or scheduled preoperative chemotherapy.