Hepatic pedicle clamping does not worsen survival after hepatic resection for colorectal liver metastasis: results from a systematic review and meta-analysis

Liver ischemia-reperfusion injury: From trigger loading to shot firing

An ischemia-reperfusion injury (IRI) results from a prolonged ischemic insult followed by the restoration of blood perfusion, being a common cause of morbidity and mortality, especially in liver transplantation. At the maximum of the potential damage, IRI is characterized by 2 main phases. The first is the ischemic phase, where the hypoxia and vascular stasis induces cell damage and the accumulation of damage-associated molecular patterns and cytokines. The second is the reperfusion phase, where the local sterile inflammatory response driven by innate immunity leads to a massive cell death and impaired liver functionality. The ischemic time becomes crucial in patients with underlying pathophysiological conditions. It is possible to compare this process to a shooting gun, where the loading trigger is the ischemia period and the firing shot is the reperfusion phase. In this optic, this article aims at reviewing the main ischemic events following the phases of the surgical timeline, considering the consequent reperfusion damage.

Impact of perioperative blood transfusions on postoperative renal function and survival after resection of colorectal liver metastases

Background and aims

Recent studies focusing on thoracic surgery suggest postoperative kidney injury depending on the amount of perioperative blood transfusions. Data investigating similar effects after resection of colorectal liver metastases (CRLM) are not available. Aim of this study was therefore to evaluate the influence of perioperative blood transfusions on postoperative renal function and survival after resection of CRLM.

Methods

Seven hundred twenty-seven cases of liver resection for CRLM were retrospectively analyzed. Renal function was measured via estimated glomerular filtration rate (eGFR) and a postoperative decline of ≥ 10% was considered substantial. Potential influences on postoperative kidney function were assessed using univariable and multivariable logistic regression analyses. Cox-regression analyses were performed to estimate the impact on overall survival (OS).

Results

Preoperative impaired kidney function (p = 0.001, OR 2.477) and transfusion of > 2 units of packed red blood cells (PRBC) (p = 0.046; OR 1.638) were independently associated with an increased risk for ≥ 10% loss of renal function. Neither a pre-existing renal impairment, nor the additional loss of renal function were associated with reduced survival. Chemotherapies in the context of primary colorectal cancer treatment (p = 0.002), age > 70 years at liver resection (p = 0.005), number (p = 0.001), and size of metastases > 50 mm (p = 0.018), duration of resection > 120 min (p = 0.006) and transfusions of > 2 units of PRBC (p = 0.039) showed a negative independent influence on OS.

Conclusion

The results demonstrate a negative impact of perioperative blood transfusions on the postoperative renal function and OS. Hence, efforts to reduce blood transfusions should be intensified.

Shorter Survival after Liver Pedicle Clamping in Patients Undergoing Liver Resection for Hepatocellular Carcinoma Revealed by a Systematic Review and Meta-Analysis

Simple Summary

Hepatocellular carcinoma (HCC) is the most prevalent tumor of the liver and represents the second most common cause of oncological-related deaths worldwide. Despite all progress made in the field, surgical resection or liver transplantation are, at the moment, the only curative therapies available. Liver resection, especially for large, central tumors, are at risk of important bleeding. Significative hemorrhage during HCC resections have been linked to an increased rate of post-operative complications and tumor recurrence. Therefore, hepatic pedicle clamping during surgery has been used in order to reduce the bleeding risks. However, this method induces ischemia/reperfusion injuries, which has also been associated with tumor recurrence. For this reason, we aimed to evaluate if pedicle clamping is indeed associated with tumor recurrence and shorter survival, by performing a systematic review of the literature and meta-analysis.

Abstract

Liver pedicle clamping minimizes surgical bleeding during hepatectomy. However, by inducing ischemia-reperfusion injury to the remnant liver, pedicle clamping may be associated with tumor recurrence in the regenerating liver. Hepatocellular carcinoma (HCC) having a high rate of recurrence, evidences demonstrating an eventual association with pedicle clamping is strongly needed. We did a systematic review of the literature until April 2020, looking at studies reporting the impact of liver pedicle clamping on long-term outcomes in patients undergoing liver resection for HCC. Primary and secondary outcomes were overall survival (OS) and disease-free survival, respectively. Results were obtained by random-effect meta-analysis and expressed as standardized mean difference (SMD). Eleven studies were included, accounting for 8087 patients. Results of seven studies were pooled in a meta-analysis. Findings indicated that, as compared to control patients who did not receive liver pedicle clamping, those who did had a significantly shorter OS (SMD = −0.172, 95%CI: −0.298 to −0.047, p = 0.007, I² = 76.8%) and higher tumor recurrence rates (odds ratio 1.36 1.01 to 1.83. p = 0.044, I² = 50.7%). This meta-analysis suggests that liver pedicle clamping may have a deleterious impact on long-term outcomes. An individual patient-data meta-analysis of randomized trials evaluating liver pedicle clamping is urgently needed.

Prognostic Impact of Pedicle Clamping during Liver Resection for Colorectal Metastases

Pedicle clamping (PC) during liver resection for colorectal metastases (CRLM) is used to reduce blood loss and allogeneic blood transfusion (ABT). The effect on long-term oncologic outcomes is still under debate. A retrospective analysis of the impact of PC on ABT-demand regarding overall (OS) and recurrence-free survival (RFS) in 336 patients undergoing curative resection for CRLM was carried out. Survival analysis was performed by both univariate and multivariate methods and propensity-score (PS) matching. PC was employed in 75 patients (22%). No increased postoperative morbidity was monitored. While the overall ABT-rate was comparable (35% vs. 37%, p = 0.786), a reduced demand for more than two ABT-units was observed (p = 0.046). PC-patients had better median OS (78 vs. 47 months, p = 0.005) and RFS (36 vs. 23 months, p = 0.006). Multivariate analysis revealed PC as an independent prognostic factor for OS (HR = 0.60; p = 0.009) and RFS (HR = 0.67; p = 0.017). For PC-patients, 1:2 PS-matching (N = 174) showed no differences in the overall ABT-rate compared to no-PC-patients (35% vs. 40%, p = 0.619), but a trend towards reduced transfusion requirement (>2 ABT-units: 9% vs. 21%, p = 0.052; >4 ABT-units: 2% vs. 11%, p = 0.037) and better survival (OS: 78 vs. 44 months, p = 0.088; RFS: 36 vs. 24 months; p = 0.029). Favorable long-term outcomes and lower rates of increased transfusion demand were observed in patients with PC undergoing resection for CRLM. Further prospective evaluation of potential oncologic benefits of PC in these patients may be meaningful.

Impact of Intermittent Pringle Maneuver on Long-Term Survival After Hepatectomy for Hepatocellular Carcinoma: Result from Two Combined Randomized Controlled Trials

BACKGROUND

Hepatectomy remains an important curative treatment for hepatocellular carcinoma (HCC). Intermittent Pringle maneuver (IPM) is commonly applied during hepatectomy for control of bleeding. Whether the ischemia/reperfusion injury brought by IPM adversely affects the operative outcomes is controversial. This study aims to examine whether the application of IPM during hepatectomy affects the long-term outcomes.

METHODS

Two randomized controlled trials (RCT) have been carried out previously to evaluate the short-term outcomes of IPM. The present study represented a post hoc analysis on the HCC patients from the first RCT and all patients from the second RCT, and the long-term outcomes were evaluated.

RESULTS

There were 88 patients each in the IPM group and the no-Pringle-maneuver (NPM) group. The patient demographics, type and extent of liver resection and histopathological findings were comparable between the two groups. The 1-, 3-, 5-year overall survival in the IPM and NPM groups was 92.0%, 82.0%, 72.1% and 93.2%, 68.8%, 58.1%, respectively (P = 0.030). The 1-, 3-, 5-year disease-free survival in the IPM and NPM groups was 73.6%, 56.2%, 49.7% and 71.6%, 49.4%, 40.3%, respectively (P = 0.366). On multivariable analysis, IPM was a favorable factor for overall survival (P = 0.035). Subgroup analysis showed that a clamp time of 16-30 min (P = 0.024) and cirrhotic patients with IPM (P = 0.009) had better overall survival.

CONCLUSION

IPM provided a better overall survival after hepatectomy for patients with HCC. Such survival benefit was noted in cirrhotic patients, and the beneficial duration of clamp was 16-30 min.

TRIAL REGISTRATION

NCT00730743 and NCT01759901 ( http://www.clinicaltrials.gov ).

Proper hepatic pedicle clamping during hepatectomy is associated with improved postoperative long-term prognosis in patients with AJCC stage IIIB hepatocellular carcinoma

Intermittent hepatic pedicle clamping (HPC) is often performed during hepatectomy. Whether it affects the long-term prognosis of hepatocellular carcinoma (HCC) patients is still controversial. This study evaluated the impact of HPC in patients with different stages of HCC. The study included 1401 patients who underwent hepatectomy in the primary cohort with 129 AJCC stage IIIB HCC patients; there were 80 AJCC stage IIIB HCC patients in the validation cohort. In each cohort, patients were placed in the long-term HPC (LTHPC) group or the short-term HPC (STHPC) group based on the cut-off time of HPC estimated by the receiver-operating characteristic (ROC) curve. Although HPC did not show significant effects on the prognosis of stage I–IIIA HCC patients in the primary cohort, 1−, 3−, and 5-year overall survival (OS) and recurrence-free survival (RFS) rates of stage IIIB HCC patients who received LTHPC (HPC time > 12 minutes) were significantly higher than those with STHPC (HPC time ≤ 12 minutes or received no HPC), similar in the validation cohort. Multivariate analysis demonstrated HPC time was an independent protective factor for RFS and OS in stage IIIB HCC patients. Herein, we report that proper HPC improved the postoperative prognosis of stage IIIB HCC patients and served as an independent protective factor.

The impact of expanded indications on short-term outcomes for resection of malignant tumours of the liver over a 30 year period

BACKGROUND

There are two philosophical approaches to planning liver resection for malignancy: one strives towards zero postoperative mortality by stringent selection of candidates, thus inherently limiting patients selected; the other, accepts a low yet definite postoperative mortality rate, and offers surgery to all those with potential gain in survival. The aim of this study was to retrospectively analyse an alternative and evolving strategy, and its impact on short-term outcomes.

METHOD

3118 consecutive hepatectomies performed in 2627 patients over 3 decades (1980-2011) were analysed. Patient demographics, tumour characteristics, operative details, and postoperative outcomes were analysed.

RESULTS

1528 patients (58%) were male. Colorectal liver metastases (1221 patients, 47%) and hepatocellular carcinoma (584 patients, 22%) were the most common diagnoses. Anatomical resections were performed in 2045 (66%), some form of vascular clamping was used in 2385 (72%), and blood transfusion was required in 1130 (36%) patients. Use of preoperative techniques to increase feasibility and safety of complex liver resections allowed expansion of indications to include sicker patients with larger tumours in the later period of the study. Overall morbidity and mortality rates were 31% and 3% respectively. During the first vs. second half of the study period the postoperative morbidity and mortality were 19% vs. 36% (p < 0.001) and 2% vs. 4% (p = 0.006) respectively.

CONCLUSION

With increasing experience, more patients were accepted for complex hepatectomies. However, there was a definite yet contained increase in postoperative morbidity and mortality.

Hepatic vascular inflow occlusion is associated with reduced disease free survival following resection of colorectal liver metastases

BACKGROUND

Hepatic vascular inflow occlusion (VIO) can be applied during resection of colorectal liver metastases (CRLM) to control intra-operative blood loss, but has been linked to accelerated growth of micrometastases in experimental models. This study aimed to investigate the effects of hepatic VIO on disease-free and overall survival (DFS and OS) in patients following resection for CRLM.

METHODS

All patients who underwent liver resection for CRLM between January 2006 and September 2015 at our center were analyzed. Hepatic VIO was performed if deemed indicated by the operating surgeon and severe ischemia was defined as ≥20 min continuous or ≥45 min cumulative intermittent VIO. Cox regression analysis was performed to identify predictive factors for DFS and OS.

RESULTS

A total of 208 patients underwent liver resection for CRLM. VIO was performed in 64 procedures (31%), and fulfilled the definition of severe ischemia in 40 patients. Patients with severe ischemia had inferior DFS (5-year DFS 32% vs. 11%, P < 0.01), and inferior OS (5-year OS 37% vs. 64%, P < 0.01). At multivariate analysis, a high clinical risk score (Hazard ratio (HR) 1.60 (1.08-2.36)) and severe ischemia (HR 1.89 (1.21-2.97)) were independent predictors of worse DFS. Severe ischemia was not an independent predictor of OS.

CONCLUSION

The present cohort study suggests that prolonged hepatic VIO during liver resection for CRLM was associated with reduced DFS. A patient-tailored approach seems advisable although larger studies should confirm these findings.

Clinical practice guidelines for the management of metastatic colorectal cancer: a consensus statement of the Hellenic Society of Medical Oncologists (HeSMO)

There is discrepancy and failure to adhere to current international guidelines for the management of metastatic colorectal cancer (CRC) in hospitals in Greece and Cyprus. The aim of the present document is to provide a consensus on the multidisciplinary management of metastastic CRC, considering both special characteristics of our Healthcare System and international guidelines. Following discussion and online communication among the members of an executive team chosen by the Hellenic Society of Medical Oncology (HeSMO), a consensus for metastastic CRC disease was developed. Statements were subjected to the Delphi methodology on two voting rounds by invited multidisciplinary international experts on CRC. Statements reaching level of agreement by ≥80% were considered as having achieved large consensus, whereas statements reaching 60-80% moderate consensus. One hundred and nine statements were developed. Ninety experts voted for those statements. The median rate of abstain per statement was 18.5% (range: 0-54%). In the end of the process, all statements achieved a large consensus. The importance of centralization, care by a multidisciplinary team, adherence to guidelines, and personalization is emphasized. R0 resection is the only intervention that may offer substantial improvement in the oncological outcomes.

The impact of portal pedicle clamping on survival from colorectal liver metastases in the contemporary era of liver resection: a matched cohort study

INTRODUCTION

Portal pedicle clamping (PPC) may impact micro-metastases' growth. This study examined the association between PPC and survival after a hepatectomy for colorectal liver metastases (CRLM).

METHODS

A matched cohort study was conducted on hepatectomies for CRLM at a single institution (2003-2012). Cohorts were selected based on PPC use, with 1:1 matching for age, time period and the Clinical Risk Score. Outcomes were overall and recurrence-free survival (OS and RFS). Cox regression was performed to assess the association between PPC and survival.

RESULTS

Of 481 hepatectomies, 26.9% used PPC. One hundred and ten pairs of patients were matched in the cohorts. There was no significant difference in OS [hazard ratio (HR) 1.18; 95% confidence interval (CI): 0.76-1.83], with a 5-year OS of 57.8% (95%CI: 52.4-63.2%) with PPC versus 62.3% (95%CI: 57.1-67.5%) without. Five-year RFS did not differ (HR 0.98; 95%CI: 0.71-1.35) with 29.7% (95%CI: 24.9-34.5%) with PPC versus 28.0% (95%CI: 23.2-32.8%) without. When adjusting for extent of resection, transfusion, operative time and surgeon, there was no difference in OS (HR 0.91; 95%CI: 0.52-1.60) or RFS (HR: 0.86; 95%CI: 0.57-1.30).

CONCLUSIONS

PPC was not associated with a significant difference in OS or RFS in a hepatectomy for CRLM. PPC remains a safe technique during hepatectomy.

Intermittent hepatic inflow occlusion during partial hepatectomy for hepatocellular carcinoma does not shorten overall survival or increase the likelihood of tumor recurrence

AIM

To investigate whether the long-term outcomes of hepatocellular carcinoma (HCC) was adversely impacted by intermittent hepatic inflow occlusion (HIO) during hepatic resection.

METHODS

1549 HCC patients who underwent hepatic resection between 1998 and 2008 were identified from a prospectively maintained database. Intermittent HIO was performed in 931 patients (HIO group); of which 712 patients had a Pringle maneuver as the mechanism for occlusion (PM group), and 219 patients had selective hemi-hepatic occlusion (SO group). There were 618 patients that underwent partial hepatectomy without occlusion (occlusion-free, OF group).

RESULTS

The 1-, 3-, and 5- year overall survival (OS) rates were 79%, 59%, and 42% in the HIO group, and 83%, 53%, and 35% in the OF group, respectively. The corresponding recurrence free survival (RFS) rates were 68%, 39%, and 22% in the HIO group, and 74%, 41%, and 18% in the OF group, respectively. There was no significant difference between the 2 groups in OS or RFS (P=0.325 and P=0.416). Subgroup analysis showed patients with blood loss over 3000 mL and those requiring transfusion suffered significantly shorter OS and RFS. Blood loss over 3000 mL and blood transfusion were independent risk factors to OS and RFS.

CONCLUSIONS

The application of intermittent HIO (PM and SO) during hepatic resection did not adversely impact either OS or RFS in patients with HCC. Intermittent HIO is still a valuable tool in hepatic resection, because high intraoperative blood loss resulting in transfusion is associated with a reduction in both OS and RFS.

The role of hepatic ischemia-reperfusion injury and liver parenchymal quality on cancer recurrence

Hepatic ischemia/reperfusion (I/R) injury is a common clinical challenge. Despite accumulating evidence regarding its mechanisms and potential therapeutic approaches, hepatic I/R is still a leading cause of organ dysfunction, morbidity, and resource utilization, especially in those patients with underlying parenchymal abnormalities. In the oncological setting, there are growing concerns regarding the deleterious impact of I/R injury on the risk of post-surgical tumor recurrence. This review aims at giving the last updates regarding the role of hepatic I/R and liver parenchymal quality injury in the setting of oncological liver surgery, using a "bench-to-bedside" approach. Relevant medical literature was identified by searching PubMed and hand scanning of the reference lists of articles considered for inclusion. Numerous preclinical models have depicted the impact of I/R injury and hepatic parenchymal quality (steatosis, age) on increased cancer growth in the injured liver. Putative pathophysiological mechanisms linking I/R injury and liver cancer recurrence include an increased implantation of circulating cancer cells in the ischemic liver and the upregulation of proliferation and angiogenic factors following the ischemic insult. Although limited, there is growing clinical evidence that I/R injury and liver quality are associated with the risk of post-surgical cancer recurrence. In conclusion, on top of its harmful early impact on organ function, I/R injury is linked to increased tumor growth. Therapeutic strategies tackling I/R injury could not only improve post-surgical organ function, but also allow a reduction in the risk of cancer recurrence.