Localized Hepatic Ischemia After Liver Resection: A Prospective Evaluation

Precision surgery for hepatocellular carcinoma

Hepatocellular carcinoma arises in the setting of cirrhosis in most cases, requiring multidisciplinary input to define resectability. In this regard, more precise surgical management considers patient factors and anatomical states, including resection margins, tumour biology, and perioperative therapy. Together with advances in surgical techniques, this integrated approach has resulted in considerable improvements in patient morbidity and oncological outcomes. Despite this, recurrence rates in hepatocellular carcinoma remain high. As the systemic treatment landscape in hepatocellular carcinoma continues to evolve and locoregional options are increasingly used, we review current and future opportunities to individualise the surgical management of patients with hepatocellular carcinoma.

Laparoscopic anatomic vs. nonanatomic liver resection for large hepatocellular carcinoma (≥5 cm) in the right lobe

OBJECTIVE

To determine the impacts and outcomes of laparoscopic anatomic liver resection (LAR) and laparoscopic nonanatomic resection (LNAR) in patients with large hepatocellular carcinoma (HCC) in the right lobe of the liver.

BACKGROUND

There are few comparative studies of LAR and LNAR for large HCC.

METHOD

Three hundred thirty-seven patients underwent liver resection for large HCC (≥5 cm) at Seoul National University Bundang Hospital, Seoul, Korea, between January 2004 and December 2022. After the exclusion of patients treated with open hepatic resection and those who had left-lobe or bilobar tumors, 94 patients were ultimately included. Patients were divided into LAR group (61 patients) and LNAR group (33 patients). After propensity score matching (PSM) with 1:1 matching, 31 patients were included in each group. The outcomes in the two groups were compared.

RESULTS

LAR group had longer operative time than LNAR group (333.7 ± 113.7 vs 210 ± 117.6 min, respectively, P < 0.001), wider safety margin (1.4 ± 1.5 vs 0.7 ± 0.7 cm, respectively, P = 0.015), and lower incidence of recurrence (25.8% vs. 54.8%, respectively, P = 0.021).

CONCLUSION

LAR required longer operative time, achieved wider safety margin, and had lower incidence of recurrence than LNAR.

The tumor microenvironment in the postsurgical liver: Mechanisms and potential targets of postoperative recurrence in human hepatocellular carcinoma

Surgery remains to be the mainstay of treatment for hepatocellular carcinoma (HCC). Nonetheless, its therapeutic efficacy is significantly impaired by postoperative recurrence, which occurs in more than half of cases as a result of intrahepatic metastasis or de novo tumorigenesis. For decades, most therapeutic strategies on inhibiting postoperative HCC recurrence have been focused on the residual tumor cells but satisfying therapeutic outcomes are barely observed in the clinic. In recent years, a better understanding of tumor biology allows us to shift our focus from tumor cells toward the postoperative tumor microenvironment (TME), which is gradually identified to play a pivotal role in tumor recurrence. In this review, we describe various surgical stress and surgical perturbation on postoperative TME. Besides, we discuss how such alternations in TME give rise to postoperative recurrence of HCC. Based on its clinical significance, we additionally highlight the potential of the postoperative TME as a target for postoperative adjuvant therapeutics.

Molecular Mechanisms of Ischaemia-Reperfusion Injury and Regeneration in the Liver-Shock and Surgery-Associated Changes

Hepatic ischemia-reperfusion injury (IRI) represents a major challenge during liver surgery, liver preservation for transplantation, and can cause hemorrhagic shock with severe hypoxemia and trauma. The reduction of blood supply with a concomitant deficit in oxygen delivery initiates various molecular mechanisms involving the innate and adaptive immune response, alterations in gene transcription, induction of cell death programs, and changes in metabolic state and vascular function. Hepatic IRI is a major cause of morbidity and mortality, and is associated with an increased risk for tumor growth and recurrence after oncologic surgery for primary and secondary hepatobiliary malignancies. Therapeutic strategies to prevent or treat hepatic IRI have been investigated in animal models but, for the most part, have failed to provide a protective effect in a clinical setting. This review focuses on the molecular mechanisms underlying hepatic IRI and regeneration, as well as its clinical implications. A better understanding of this complex and highly dynamic process may allow for the development of innovative therapeutic approaches and optimize patient outcomes.

Liver Surgery: Important Considerations for Pre- and Postoperative Imaging

Liver surgery may be a curative treatment option not only for primary liver neoplasms but also for liver metastases in selected patients. The number of liver surgeries performed worldwide has increased, but surgical morbidity associated with these surgeries remains significant. Therefore, radiologists need to understand the terminology, surgical techniques, resectability and unresectability criteria, and possible postoperative complications as these are part of the decision-making process. Because vascular and biliary variations are common, an adequate preoperative anatomic evaluation determines the best surgical technique, helps identify patients in whom additional surgical steps will be required, and reduces the risk of inadvertent injury. The surgeon must ensure that the future liver remnant is sufficient to maintain adequate function, aided by the radiologist who can provide valuable information such as the presence of steatosis, biliary dilatation, signs of cirrhosis, and portal hypertension, in addition to the volume of the future liver remnant. Postoperative complications must also be understood and evaluated. The most common postoperative complications are vascular (bleeding, thrombosis, and ischemia), biliary (fistulas, bilomas, and strictures), infectious (incisional or deep), those related to liver failure, and even tumor recurrence. An invited commentary by Winslow is available online. Online supplemental material is available for this article. ^©RSNA, 2022.

Simulation of portal/hepatic vein associated remnant liver ischemia/congestion by three-dimensional visualization technology based on preoperative CT scan

Background

Remnant liver hypoperfusion is frequently observed after hepatectomy, and associated with a higher risk of postoperative complications and poorer survival. However, the development of remnant liver hypoperfusion was not fully understood.

Methods

We retrospectively analyzed patients who received hepatectomy and took contrast-enhanced computed tomography (CT) scans before, 1-week (POW1) and 4-week (POW4) after resection in our department from June 2017 to July 2019. We simulated and estimated the occurrence of portal-vein-related remnant liver ischemia (RLI) and hepatic-vein-related remnant liver congestion (RLC) after hepatectomy via three-dimensional visualization technology (3DVT) according to blood vessels ligated in the resection; then we analyzed association between the estimated RLI, RLC, and postoperative clinical outcomes.

Results

A total of 102 eligible patients were analyzed. Remnant liver hypoperfusion was observed in 47 (46%) patients in the POW1 CT scans and shrunk in the POW4 CT scans. RLC had better diagnostic significance than RLI in predicting remnant liver hypoperfusion [area under receiver operating characteristic (ROC) curve: 0.745 vs. 0.569, P=0.026]. Multivariate analysis showed that larger RLI [odds ratio (OR), 1.154; 95% confidence interval (CI), 1.075-1.240; P<0.001] was independent risk factor for post-hepatectomy liver failure (PHLF). Besides, larger RLC (OR, 1.114; 95% CI, 1.032-1.204; P=0.006) was independent risk factor for major postoperative complications.

Conclusions

Remnant liver hypoperfusion can be predicted during the preoperative surgical plan by 3DVT. Portal vein related RLI was associated with PHLF, and hepatic vein related RLC was associated with major postoperative complications. Preservation of the hepatic vein and complete removal of the perfusion territory of ligated vessels are essential procedures to reduce RLI/RLC and the risk of PHLF or other surgical complications.

Clinical Value of Trans-parenchymal Compressing Suture to Decrease the Cutting Surface Related Complications after Non-anatomical Liver Resection

Non-anatomical liver resection with appropriate resection margin is regarded as a potential curative treatment for selected major hepatic carcinoma due to preserving maximal normal liver, especially in cirrhotic patients. But occurrence of cutting surface related complications becomes a main challenge. From June 2010 to June 2016, 448 patients with major hepatic carcinoma received non-anatomical liver resection in our liver surgery center. After excluding 66 cases that were incongruent with the purpose of study, 235 patients undergoing transparenchymal compressing suture (TCS) to "not good" cutting surface were allocated as study group; 147 patients with exposed surface (ES) were matched as control group. The characteristics of postoperative drainage, postoperative hepatic and renal functions, hospital days, and outcomes were collected retrospectively. We further compared cutting surface related complications under different levels of liver cirrhosis between the two groups. Compared with ES group, patients in TCS group had a decreased incidence of cutting surface related complications (14.3% vs. 6.8%, P=0.011) and a decreased probability of interventions for cutting surface related complications (8.2% vs. 3.4%, P=0.042). TCS application was much more effective to prevent cutting surface related complications in patients with moderate and severe cirrhosis (5.4% vs. 15.8%, P=0.003). Postoperative hepatic and renal function, hospital days and mortality did not differ between the two groups. In conclusion, TCS decreases the probability of cutting surface related complications and postoperative interventions for related complications, especially in patients with moderate and severe cirrhosis.

Remnant Liver Ischemia as a Prognostic Factor for Cancer-Specific Survival After Resection of Colorectal Liver Metastases

IMPORTANCE

Ischemia-reperfusion injury during hepatic resection has been shown to accelerate progression of liver cancer. However, the prognostic relevance of remnant liver ischemia (RLI) after resection of colorectal liver metastases (CLMs) is unknown to date.

OBJECTIVES

To assess the prognostic influence of RLI after resection of CLMs and to identify correlates of greater extent of RLI.

DESIGN, SETTING, AND PARTICIPANTS

This study was a retrospective analysis at The University of Texas MD Anderson Cancer Center based on prospectively collected data. The study identified 202 patients who underwent curative resection of CLMs between January 1, 2008, and December 31, 2014, and had enhanced computed tomographic images obtained within 30 days after surgery.

MAIN OUTCOMES AND MEASURES

Remnant liver ischemia was defined as reduced or absent contrast enhancement during the portal phase. Postoperative RLI was classified as grade 0 (none), 1 (marginal), 2 (partial), 3 (segmental), or 4 (necrotic) as previously defined. Experienced members of the surgical team retrospectively performed imaging assessments. Team members were masked to the postoperative outcomes. Survival after resection was stratified by RLI grade. Predictors of RLI grade 2 or higher and survival were identified.

RESULTS

Among 202 patients (median [range] age, 56 [27-87] years; 84 female), the RLI grades were as follows: grade 0 (105 patients), grade 1 (47 patients), grade 2 (45 patients), grade 3 (5 patients), and grade 4 (0 patients). Recurrence-free survival (RFS) and cancer-specific survival (CSS) rates after hepatic resection were worse in patients with RLI grade 2 or higher vs grade 1 or lower (RFS at 3 years, 6.4% [3 of 50] vs 39.2% [60 of 152]; P < .001 and CSS at 5 years, 20.7% [10 of 50] vs 63.7% [97 of 152]; P < .001). A largest metastasis at least 3 cm (OR, 2.74; 95% CI, 1.35-5.70; P = .005), multiple CLMs (OR, 2.51; 95% CI, 1.25-5.24; P = .009), and nonanatomic resection (odds ratio [OR], 3.29; 95% CI, 1.52-7.63; P = .002) were associated with RLI grade 2 or higher. A largest metastasis at least 3 cm (hazard ratio [HR], 1.70; 95% CI, 1.01-2.88; P = .045), mutant RAS (HR, 2.15; 95% CI, 1.27-3.64; P = .005), and RLI grade 2 or higher (HR, 2.90; 95% CI, 1.69-4.84; P < .001) were associated with worse CSS.

CONCLUSIONS AND RELEVANCE

In this study, remnant liver ischemia grade 2 or higher was associated with worse CSS after resection of CLMs. High-quality anatomic surgery to minimize RLI after resection is essential.

Traditional surgical planning of liver surgery is modified by 3D interactive quantitative surgical planning approach: a single-center experience with 305 patients

BACKGROUND

Decision making and surgical planning are to achieve the precise balance of maximal removal of target lesion, maximal sparing of functional liver remnant volume, and minimal surgical invasiveness and therefore, crucial in liver surgery. The aim of this prospective study was to validate the accuracy and predictability of 3D interactive quantitative surgical planning approach (IQSP), and to evaluate the impact of IQSP on traditional surgical plans based on 2D images.

METHODS

A total of 305 consecutive patients undergoing hepatectomy were included in this study. Surgical plans were created by traditional 2D approach using picture archiving and communication system (PACS) and 3D approach using IQSP respectively by two groups of physicians who did not know the surgical plans of the other group. The two surgical plans were submitted to the chief surgeon for selection before operation. The specimens were weighed. The two surgical plans were compared and analyzed retrospectively based on the operation results.

RESULTS

The two surgical plans were successfully developed in all 305 patients and all the 3D IQSP surgical plans were selected as the final decision. Total 278 patients successfully underwent surgery, including 147 uncomplex hepatectomy and 131 complex hepatectomy. Twenty-seven patients were withdrawn from hepatectomy. In the uncomplex group, the two surgical plans were the same in all 147 patients and no statistically significant difference was found among 2D calculated resection volume (2D-RV), 3D IQSP calculated resection volume (IQSP-RV) and the specimen volume. In the complex group, the two surgical plans were different in 49 patients (49/131, 37.4%). According to the significance of differences, the 49 different patients were classified into three grades. No statistically significant difference was found between IQSP-RV and specimen volume. The coincidence rate of territory analysis of IQSP with operation was 92.1% (93/101) for 101 patients of anatomic hepatectomy.

CONCLUSIONS

The accuracy and predictability of 3D IQSP were validated. Compared with traditional surgical planning, 3D IQSP can provide more quantitative information of anatomic structure. With the assistance of 3D IQSP, traditional surgical plans were modified to be more radical and safe.

Association of Remnant Liver Ischemia With Early Recurrence and Poor Survival After Liver Resection in Patients With Hepatocellular Carcinoma

Importance

The remnant liver after hepatectomy may have inadequate blood supply, especially following nonanatomical resection or vascular damage.

Objective

To evaluate whether remnant liver ischemia (RLI) may have an adverse effect on long-term survival and morbidity after liver resection in patients with hepatocellular carcinoma.

Design, Setting, and Participants

This study was a retrospective analysis at Seoul National University Bundang Hospital. Remnant liver ischemia was graded on postoperative computed tomographic scans in 328 patients who underwent hepatectomy for hepatocellular carcinoma between January 1, 2004, and December 31, 2013.

Main Outcomes and Measures

Remnant liver ischemia was defined as reduced or absent contrast enhancement during the venous phase. Remnant liver ischemia was classified as minimal (none or marginal) or severe (partial, segmental, or necrotic).

Results

Among 328 patients (252 male and 76 female; age range, 26-83 years [mean age, 58.2 years]), radiologic signs of severe RLI were found in 98 patients (29.9%), of whom 63, 16, and 19 had partial, segmental, or necrotic RLI, respectively. These patients experienced more complications and longer hospital stay than patients with minimal RLI. Preoperative history of transarterial embolization (odds ratio [OR], 1.77; 95% CI, 1.02-3.03; P = .04), use of the Pringle maneuver (OR, 1.96; 95% CI, 1.08-3.58; P = .03), and longer operative time (OR, 1.003; 95% CI, 1.002-1.005; P < .001) were independent risk factors for severe RLI. Early recurrence rates within 6 (60.2% vs 9.6%) or 12 (79.6% vs 18.7%) months after hepatectomy were higher in patients with severe RLI than in patients without RLI (P < .001). Severe remnant liver ischemia was an independent risk factor for overall survival (OR, 6.98; 95% CI, 4.27-11.43; P < .001) and disease-free survival (OR, 5.15; 95% CI, 3.62-7.35; P < .001).

Conclusions and Relevance

Preventive management and technical refinements in hepatectomy are important to decrease the risk of RLI and to improve survival of patients with hepatocellular carcinoma.

Clinical significance of liver ischaemia after pancreatic resection

BACKGROUND

Liver ischaemia after pancreatic resection is a rare but potentially serious complication. The aim of this study was to determine the impact of postoperative liver ischaemia after pancreatic resection.

METHODS

All consecutive patients undergoing pancreatic resection between January 2007 and August 2008 in the Department of Surgery in Heidelberg were identified retrospectively from a prospectively collected database and analysed with a focus on postoperative hepatic perfusion failure. Laboratory data, computed tomography (CT) findings, symptoms, therapy and outcome were recorded.

RESULTS

A total of 762 patients underwent pancreatic resection in the study period. Seventeen patients (2·2 per cent) with a postoperative increase in liver enzymes underwent contrast-enhanced CT for suspected liver perfusion failure. The types of perfusion failure were hypoperfusion without occlusion of major hepatic vessels (6 patients) and ischaemia with arterial (5) and/or portal vein (6) involvement. The overall mortality rate was 29 per cent (5 of 17 patients). Therapy included conservative treatment (7), radiological or surgical revascularization and necrosectomy or resection of necrotic liver tissue (10). Outcome varied from full recovery (4 patients) to moderate systemic complications (6) and severe complications (7) including death. Simultaneous involvement of the portal vein and hepatic artery was always fatal.

CONCLUSION

Postoperative liver perfusion failure is a rare but potentially severe complication following pancreatic surgery requiring immediate recognition and, if necessary, radiological or surgical intervention.