Vascular resection and reconstruction in hilar cholangiocarcinoma

Effects of different preservation methods of human iliac veins

With the progress of vascular anastomosis technology, the radical resection surgery of cancer combining with vascular resection and reconstruction has been focused by surgeon. As a natural substitute material for blood vessel, vascular allografts have good vascular compliance and histocompatibility. Generally, the donated veins could not be used immediately, and need to be well preserved. So, it is greatly significant to do research in the preservation effects of different preservation methods on veins. In this study, the effects of different preservative methods of human iliac veins were compared and analyzed in terms of cell viability, vascular wall structure and tension resistance. The donated human iliac veins were randomly divided into three groups: Cold Storage Group (4 °C) (CSG), Frozen Storage Group (-186 °C) (FSG)and Fresh Control Group (FCG). Six detection time-points of preservation for 1, 3, 5, 7, 14, 28 days were set respectively. There are ten samples in each group and each time-point separately. Survival and apoptosis of vascular cell were evaluated by MTT assay and Tunel fluorescence staining. Tensile test was used to evaluate mechanical properties of vessels. The changes of vascular endothelial cells, smooth muscle cells, collagen fibers and elastic fibers were evaluated by HE staining, Masson staining and EVG staining. Furthermore, the changes of organelles were observed by transmission electron microscope. With the extension of preservation period, the vascular cell viability and tension resistance of two groups decreased, and the apoptotic cells increased gradually. The apoptosis index of CSG was higher than FSG at each time point (P < 0.05). In terms of cell viability, CSG was higher within 3 days (P < 0.05), both groups were same between 3 and 14 days, and then CSG lower than FSG after 14 days (P < 0.05). In terms of tension resistance, CSG was stronger than FSG (P < 0.05) in first 7 days, both groups were same in 2nd week, and then CSG was weaker in 4th week (P < 0.05). In terms of vascular wall structure, in CSG, vascular endothelial cells were damaged and shed, smooth muscle cells were edema after 14 days, but the cell membrane and intercellular connection were still intact. In 4th week, endothelial cells were completely damaged and shed, the boundary of smooth muscle cell membrane was unclear, intercellular connection was damaged. Moreover, organelles were destroyed and disappeared, perinuclear condensation of chromatin was observed, and some cells had incomplete nuclear membrane or nuclear fragmentation; However, there were no obvious changes in the FSG within 28 days. Finally, local exfoliation and destruction of endothelial cells and edema-like changes of organelles were observed; the collagen fibers and elastic fibers of blood vessels in the two groups had no obvious damage and change within 28 days. For excised human iliac vein, cold and frozen storage can effectively preserve the cell viability, wall structure and tension resistance of blood vessels. With the extension of preservation time, the related performance of vessels declined in varying degrees. Within first week, the effect of cold storage is better than frozen storage, but frozen storage is significantly better than cold storage after 2 weeks.

Protective Effects of Different Hypothermal Preservation Solutions on Structure and Function of Isolated Rat Arteries

OBJECTIVE

With the increasing application of vascular reconstruction in surgical procedures, allogeneic vessels are becoming more popular in clinical practice due to their abundant sources, precise diameter matching, improved histocompatibility, and higher long-term patency rate. This study aimed to investigate the protective effect of various preservation solutions on the function and structure of the isolated rat abdominal aorta preserved under hypothermal conditions.

METHODS

The study utilized a total of 150 Sprague-Dawley (SD) rats, with 144 rats allocated to the experimental groups and 6 rats allocated to the control groups. The abdominal aorta of the rats was chosen as the subject of our research. The aorta in the experimental groups were randomly assigned to 4 groups: University of Wisconsin (UW) solution group, histidine-tryptophan-ketoglutarate (HTK) solution group, normal saline (NS) group, and sodium lactate Ringer's solution (RS) group. Samples were subjected to examination after preservation periods of 1 day, 3 days, 5 days, 7 days, 14 days, 30 days, and 90 days. Evaluation of vascular physiological function involved detecting and assessing vasoconstriction ability and measuring cell viability through the MTT test. Evaluation of the vascular wall structure involved tension tolerance tests and pathological staining.

RESULTS

The pathogen-positive rate in the HTK group and NS group at 1 month was 16.7%. Regarding the vascular skeleton structure, both the UW group and HTK group exhibited intact structures after 2 weeks of preservation, with slightly edematous collagen and elastic fibers, which was significantly better than that of the NS group and RS group. In terms of cell activity and contractile function, all preservation groups showed similar effects within 2 weeks. However, after 2 weeks, the UW group showed the most favorable preservation effect (P<0.05). In terms of vascular tension, different groups exhibited similar effects within 1 week. However, after 2 weeks, the UW group showed the best preservation effect (P<0.05).

CONCLUSION

All 4 types of preservation solution had a preservation effect on the structure and function of isolated blood vessels during short-term hypothermal preservation. However, after 2-week preservation, the UW solution was found to be the most suitable solution for the preservation of blood vessels.

Effects of different preservation schemes on isolated rat artery

Allogeneic blood vessels are regarded as one of the best natural substitutes for diseased blood vessels due to their good vascular compliance and histocompatibility. Since the supply and demand of allograft blood vessels do not always match in time and space, a good preservation scheme for isolated blood vessels is essential. The abdominal aortas of 110 male Sprague-Dawley (SD) rats were randomly divided into three groups, including cold storage group (4°C) (CSG), frozen storage group (FSG) and ambient storage group (25 ± 2°C) (ASG). Seven time points of preservation for 1, 3, 5, 7, 14, 30 and 90 days were set for detection. The changes in vascular physiological function were evaluated by MTT test and vasoconstriction ability detection, and the changes in vascular wall structure were evaluated by the tension tolerance test and pathological staining. The vascular function of CSG was better than FSG within first the 7 days, but the result was opposite since the 14th day. The vascular wall structure, collagen and elastic fibres of vessels, in CSG, showed oedema within 30 days, and continuous disintegration and rupture at 90 days. The vessel wall structure of FSG remained intact within 90 days. The tensile strength of the vessels in CSG was better than that in FSG within 5 days, and there was no statistical difference between the two groups between the 7th and 30th day, and then, the FSG was higher than CSG on the 90th day. Both cold storage and frozen storage could be applied as safe and effective preservation schemes for isolated rat artery within first 30 days. Cold storage is recommended when the storage time is <14 days, and then, frozen storage is better.

Comparative study on left-sided versus right-sided hepatectomy for resectable peri-hilar cholangiocarcinoma: a systematic review and meta-analysis

BACKGROUND

Peri-hilar cholangiocarcinoma (pCCA) is a unique entity, and radical surgery provides the only chance for cure and long-term survival. But it is still under debate which surgical strategy (i.e., left-sided hepatectomy, LH or right-sided hepatectomy, RH) should be followed and benefitted.

METHODS

We performed a systematic review and meta-analysis to analyze the clinical outcomes and prognostic value of LH versus RH for resectable pCCA. This study followed the PRISMA and AMSTAR guidelines.

RESULTS

A total of 14 cohort studies include 1072 patients in the meta-analysis. The results showed no statistical difference between the two groups in terms of overall survival (OS) and disease-free survival (DFS). But compared to the LH group, the RH group exhibited more employment of preoperative portal vein embolization (PVE), higher rate of overall complications, post-hepatectomy liver failure (PHLF), and perioperative mortality, while LH was associated with higher frequency of arterial resection/reconstruction, longer operative time, and more postoperative bile leakage. There was no statistical difference between the two groups in terms of preoperative biliary drainage, R0 resection rate, portal vein resection, intraoperative bleeding, and intraoperative blood transfusion rate.

CONCLUSIONS

According to our meta-analyses, LH and RH have comparable oncological effects on curative resection for pCCA patients. Although LH is not inferior to RH in DFS and OS, it requires more arterial reconstruction which is technically demanding and should be performed by experienced surgeons in high-volume centers. Selectin of surgical strategy between LH and RH should be based on not only tumor location (Bismuth classification) but also vascular involvement and future liver remnant (FLR).

Systematic review and meta-analysis of surgery for hilar cholangiocarcinoma with arterial resection

BACKGROUND

With the advances in multimodality treatment, an analysis of the outcome of arterial resections (AR) in surgery of cholangiocarcinoma is lacking. The aim of this meta-analysis was to summarize the currently available evidence onof AR for the treatment of cholangiocarcinoma.

METHODS

A systematic literature search was carried out according to PRISMA guidelines.

RESULTS

10 retrospective cohort studies published from 2007 to 2020 with 2530 patients (408 AR group and 2122 control group) were identified. Higher in-hospital mortality rates (6.8% vs 3.3%, OR 2.65, 95% CI [1.27; 5.32], p = 0.009), higher morbidity rates (Clavien-Dindo classification ≥3 ) (52% vs 47%, OR 1.44, 95% CI [1.02; 1.75], p = 0.04) and lower 1-year, 3-year and 5-year survival rates (54% vs 69%, OR 0.55, 95% CI [0.34; 0.91 p = 0.02), (34% vs 38%, OR 0.74, 95% CI [0.55; 0.98, p = 0.03), (18% vs 29%, OR 0.54, 95% CI [0.39; 0.75, p = 0.0002) were observed in the AR group when compared to the control group.

CONCLUSION

Evidence from non-randomized studies shows a higher morbidity and mortality and shorter long-term survival in patients undergoing AR. However, the results are prone to selection bias, and only randomized trials comparing AR and palliative treatments AR might reveal a possible benefit of AR.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO ID 223396.

Establishment of rat allogenic vein replacement model and pathological characteristics of the replaced vessels

Background

With the advancement of vascular anastomosis techniques in recent years, radical surgery for tumors combined with venous vascular resection and reconstruction has been widely used. This study intends to establish two different rat vein replacement models, and further analyze the pathological changes of blood vessels after replacement.

Methods

Brown-Norway (BN) rats were selected as donors and recipients, randomly divided into control group, cuff group (1-week group, 2-week group, and 4-week group), and suture group (1-week group, 2-week group, and 4-week group), with 6 rats in each group. The perioperative conditions, inner diameter, flow velocity and histopathological changes of the replaced vessels at different time points were analyzed.

Results

Both cuff group and suture group can safely establish the rat vein replacement model. From the surgical operation, the operation time and venous cross-clamp time in the cuff group were shorter than those in the suture group (P &lt; 0.05). At 2 and 4 weeks after operation, the diameter of suture group was wider than that of cuff group, and the flow rate was faster (P &lt; 0.05). With prolonged postoperative survival, the wall of the replaced vessels underwent infiltration of CD4+ and CD8+ lymphocytes and high TGF-β1 gene expression. This leads to the proliferation of blood vessels and intimal layer. The results of vascular pathological staining showed that the infiltration degree of CD4+ lymphocytes at 2 weeks after operation and CD8+ lymphocytes at 4 weeks after operation in the suture group was lighter than that in the cuff group (P &lt; 0.05). Meanwhile, TGF-β1 gene content at 4 weeks after operation in suture group was significantly lower than that in cuff group (P &lt; 0.05).

Conclusion

Compared with cuff method, suture method is more suitable for the study of long-term pathological changes after vein replacement in rats. The main pathological changes in the long term after venous replacement in syngeneic background may be vascular fibrosis caused by inflammatory cell infiltration.

Intravenous combined with intrabiliary contrast-enhanced ultrasound in the evaluation of resectability of hilar cholangiocarcinomas

OBJECTIVE

To investigate the application value of combined intravenous contrast-enhanced ultrasound (IV-CEUS) with intrabiliary contrast-enhanced ultrasound (IB-CEUS) in the preoperative evaluation of hilar cholangiocarcinoma (HCCA) resectability.

METHODS

Clinical data from 82 patients with HCCA confirmed by surgery and pathology were retrospectively analyzed. Preoperative IV-CEUS + IB-CEUS and magnetic resonance cholangiopancreatography (MRCP) were performed and the results were compared with surgical and pathological findings.

RESULTS

The accuracy of the Bismuth-Corlette classification confirmed by IV-CEUS + IB-CEUS and MRCP was 95.12% (78/82) and 87.8% (72/82), respectively. The diagnostic precision of IV-CEUS + IB-CEUS was better than MRCP (p = 0.001). The sensitivity, specificity, and precision of CEUS for diagnosing lymph node metastases (72.7%, 93.3%, and 87.8%), intrahepatic metastases (78.6%, 98.5%, and 93.9%), invasion of the hepatic artery (92.9%, 98.5%, and 97.6%) and invasion of the portal vein (93.8%, 98.5%, and 97.6%) of HCCA were, respectively. The consistency between the preoperative evaluation of resectability confirmed by IV-CEUS +IB-CEUS and MRCP was 85.4% (70/82) and 78.0% (64/82), respectively. In addition, the evaluations did not have statistically significant differences (p > 0.05). There were no significant differences between the two evaluations (p = 0.266).

CONCLUSION

IV-CEUS combined with IB-CEUS has significant value in classifying HCCA and evaluating the resectability of lymph node metastases, liver metastases, and vessel invasion.

Surgery With Arterial Resection for Hilar Cholangiocarcinoma: Protocol for a Systematic Review and Meta-analysis

Background

In light of recent advances in multimodality treatment, an analysis of vascular resection outcomes in surgery for hilar cholangiocarcinoma is lacking.

Objective

The aim of this meta-analysis is to summarize the currently available evidence on outcomes of patients undergoing arterial resection for the treatment of hilar cholangiocarcinoma.

Methods

A systematic literature search in the databases PubMed/MEDLINE, Cochrane Library, and CINAHL, and the trial registries ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform will be carried out. Predefined outcomes are mortality (100-day and in-hospital), morbidity (Clavien-Dindo classification, any type of complication), vascular complications (thrombosis or stenosis of the portal vein or hepatic artery, pseudoaneurysms), liver failure, postoperative bleeding, duration of surgery, reoperation rate, length of hospital stay, survival time, actuarial survival (2-, 3-, and 5-year survival), complete/incomplete resection rates, histologic arterial invasion, and lymph node positivity (number of positive lymph nodes and lymph node ratio).

Results

Database searches will commence in December 2020. The meta-analysis will be completed by December 2021.

Conclusions

Our findings will enable us to present the current evidence on the feasibility, safety, and oncological effectiveness of surgery for hilar cholangiocarcinoma with arterial resection. Our data will support health care professionals and patients in their clinical decision-making.

Trial Registration

PROSPERO 223396; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=223396

International Registered Report Identifier (IRRID)

DERR1-10.2196/31212

Effect of vascular resection for perihilar cholangiocarcinoma: a systematic review and meta-analysis

OBJECTIVE

To evaluate the effect of vascular resection (VR), including portal vein resection (PVR) and hepatic artery resection (HAR), on short- and long-term outcomes in patients with perihilar cholangiocarcinoma (PHC).

BACKGROUND

Resection surgery and transplantation are the main treatment methods for PHC that provide a chance of long-term survival. However, the efficacy and safety of VR, including PVR and HAR, for treating PHC remain controversial.

METHODS

This study was registered at the International Prospective Register of Systematic Reviews (CRD42020223330). The EMBASE, PubMed, and Cochrane Library databases were used to search for eligible studies published through November 28, 2020. Studies comparing short- and long-term outcomes between patients who underwent hepatectomy with or without PVR and/or HAR were included. Random- and fixed-effects models were applied to assess the outcomes, including morbidity, mortality, and R0 resection rate, as well as the impact of PVR and HAR on long-term survival.

RESULTS

Twenty-two studies including 4,091 patients were deemed eligible and included in this study. The meta-analysis showed that PVR did not increase the postoperative morbidity rate (odds ratio (OR): 1.03, 95% confidenceinterval (CI): [0.74-1.42], P = 0.88) and slightly increased the postoperative mortality rate (OR: 1.61, 95% CI [1.02-2.54], P = 0.04). HAR did not increase the postoperative morbidity rate (OR: 1.32, 95% CI [0.83-2.11], P = 0.24) and significantly increased the postoperative mortality rate (OR: 4.20, 95% CI [1.88-9.39], P = 0.0005). Neither PVR nor HAR improved the R0 resection rate (OR: 0.70, 95% CI [0.47-1.03], P = 0.07; OR: 0.77, 95% CI [0.37-1.61], P = 0.49, respectively) or long-term survival (OR: 0.52, 95% CI [0.35-0.76], P = 0.0008; OR: 0.43, 95% CI [0.32-0.57], P < 0.00001, respectively).

CONCLUSIONS

PVR is relatively safe and might benefit certain patients with advanced PHC in terms of long-term survival, but it is not routinely recommended. HAR results in a higher mortality rate and lower overall survival rate, with no proven benefit.