Margin status after laparoscopic resection of colorectal liver metastases: does a narrow resection margin have an influence on survival and local recurrence?

Analysis of survival factors after hepatic resection for colorectal cancer liver metastases: Does the R1 margin matter?

Introduction

The effect of liver margin on colorectal cancer liver metastases (CRLM) after hepatectomy has been controversial. In this study, we conducted a postoperative follow-up study of 205 patients with CRLM to clarify whether a positive margin is significant and to define the risk factors affecting CRLM survival.

Methods

The data of 205 patients with CRLM who underwent surgical treatment at the Third Hospital of Peking University in the Department of General Surgery from January 2009 to December 2020 were retrospectively analyzed. The general data, surgical data and postoperative follow-up of the patients were statistically analyzed.

Results

There were 130 cases (63.4%) of R0 resection and 75 cases (36.6%) of R1 resection. There were 136 males and 69 females, age 61 ± 11 years, and body mass index (BMI 24.5 ± 3.3 kg/m²). The overall survival rates at 1, 3, and 5 years for the entire cohort were 93.4%, 68.4%, and 45.5% in the R0 resection group vs. 93.2%, 53.7%, and 42% in the R1 resection group, respectively, which were not statistically significant (P = 0.520). The 1-, 3-, and 5-year disease-free survival rates of 63.2%, 33.3%, and 29.7% were significantly better in the R0 resection group than in the R1 resection group of 47.9%, 22.7%, and 17.7% (P = 0.016), respectively. After multivariable analysis, carbohydrate antigen 19-9 (CA19-9) > 39 U/ml (HR = 2.29, 95% CI: 1.39-3.79, P = 0.001), primary tumor perineural invasion (HR = 1.78, 95% CI: 1.01-3.13, P = 0.047), and BMI > 24 kg/m2 (HR = 1.75, 95% CI: 1.05-2.93, P = 0.033) were independently associated with poorer overall patient survival. The number of liver metastases >2 (HR = 1.65, 95% CI: 1.10-2.47, P = 0.016), the maximum diameter of metastases ≥50 mm (HR = 1.67, 95% CI: 1.06-2.64, P = 0.026), and vascular invasion of the primary tumor (HR = 1.65, 95% CI: 1.03-2.64, P = 0.038) were also independently associated with poorer disease-free survival.

Conclusion

In patients undergoing hepatectomy for CRLM, the negative effect of the R1 margin should be downplayed, and although the disease-free survival of the R1 margin is shorter than that of the R0 margin, it has no impact on overall survival. To improve overall survival, extra attention should be given to the factors of preoperative BMI, preoperative CA19-9, and the presence of perineural invasion of the primary tumor.

Liver Colonization by Colorectal Cancer Metastases Requires YAP-Controlled Plasticity at the Micrometastatic Stage

Micrometastases of colorectal cancer can remain dormant for years prior to the formation of actively growing, clinically detectable lesions (i.e., colonization). A better understanding of this step in the metastatic cascade could help improve metastasis prevention and treatment. Here we analyzed liver specimens of patients with colorectal cancer and monitored real-time metastasis formation in mouse livers using intravital microscopy to reveal that micrometastatic lesions are devoid of cancer stem cells (CSC). However, lesions that grow into overt metastases demonstrated appearance of de novo CSCs through cellular plasticity at a multicellular stage. Clonal outgrowth of patient-derived colorectal cancer organoids phenocopied the cellular and transcriptomic changes observed during in vivo metastasis formation. First, formation of mature CSCs occurred at a multicellular stage and promoted growth. Conversely, failure of immature CSCs to generate more differentiated cells arrested growth, implying that cellular heterogeneity is required for continuous growth. Second, early-stage YAP activity was required for the survival of organoid-forming cells. However, subsequent attenuation of early-stage YAP activity was essential to allow for the formation of cell type heterogeneity, while persistent YAP signaling locked micro-organoids in a cellularly homogenous and growth-stalled state. Analysis of metastasis formation in mouse livers using single-cell RNA sequencing confirmed the transient presence of early-stage YAP activity, followed by emergence of CSC and non-CSC phenotypes, irrespective of the initial phenotype of the metastatic cell of origin. Thus, establishment of cellular heterogeneity after an initial YAP-controlled outgrowth phase marks the transition to continuously growing macrometastases.

SIGNIFICANCE

Characterization of the cell type dynamics, composition, and transcriptome of early colorectal cancer liver metastases reveals that failure to establish cellular heterogeneity through YAP-controlled epithelial self-organization prohibits the outgrowth of micrometastases. See related commentary by LeBleu, p. 1870.

Laparoscopic liver resection for colorectal liver metastases - short- and long-term outcomes: A systematic review

BACKGROUND

For well-selected patients and procedures, laparoscopic liver resection (LLR) has become the gold standard for the treatment of colorectal liver metastases (CRLM) when performed in specialized centers. However, little is currently known concerning patient-related and peri-operative factors that could play a role in survival outcomes associated with LLR for CRLM.

AIM

To provide an extensive summary of reported outcomes and prognostic factors associated with LLR for CRLM.

METHODS

A systematic search was performed in PubMed, EMBASE, Web of Science and the Cochrane Library using the keywords "colorectal liver metastases", "laparoscopy", "liver resection", "prognostic factors", "outcomes" and "survival". Only publications written in English and published until December 2019 were included. Furthermore, abstracts of which no accompanying full text was published, reviews, case reports, letters, protocols, comments, surveys and animal studies were excluded. All search results were saved to Endnote Online and imported in Rayyan for systematic selection. Data of interest were extracted from the included publications and tabulated for qualitative analysis.

RESULTS

Out of 1064 articles retrieved by means of a systematic and grey literature search, 77 were included for qualitative analysis. Seventy-two research papers provided data concerning outcomes of LLR for CRLM. Fourteen papers were eligible for extraction of data concerning prognostic factors affecting survival outcomes. Qualitative analysis of the collected data showed that LLR for CRLM is safe, feasible and provides oncological efficiency. Multiple research groups have reported on the short-term advantages of LLR compared to open procedures. The obtained results accounted for minor LLR, as well as major LLR, simultaneous laparoscopic colorectal and liver resection, LLR of posterosuperior segments, two-stage hepatectomy and repeat LLR for CRLM. Few research groups so far have studied prognostic factors affecting long-term outcomes of LLR for CRLM.

CONCLUSION

In experienced hands, LLR for CRLM provides good short- and long-term outcomes, independent of the complexity of the procedure.

Prospective Non-Randomized Study of Intraoperative Assessment of Surgical Resection Margin of Colo-Rectal Liver Metastases

Introduction: More than 50% of patients with colorectal cancer (CRC) develop liver metastases during the natural course of disease. Surgical resection is currently the most potentially curative method in the treatment of colorectal liver metastases (CRLM). The goal of surgery is to achieve a negative resection margin (RM) of at least 1 mm, which provides the best prognosis for patients. The RM can be assessed by the pathologist of the resected liver specimen (RLS) and by the surgeon intraoperatively. The aim of this research paper is to determine the degree of agreement on intraoperative assessment of the RM by the surgeon and histopathological RM assessment by the pathologist.

Material and methods: This prospective non-randomized double-blind study was approved by the Ethics Committee of the Oncology Institute of Vojvodina and registered on ClinicalTrials.gov #NCT04634526. The study was conducted at the Oncology Institute of Vojvodina, Sremska Kamenica, Serbia. An experienced hepatobiliary surgeon assessed RM for every specimen intra-operatively, immediately after CRLM resection. Resected CRLM lesions were analyzed by two experienced pathologists. These data were compared with pathological RM assessment as a “gold standard”. RM of 1 mm or more was rated as negative RM (RM-). Disease-free survival (DFS) and recurrence rate was calculated by RM status defined by surgeon and by pathologist.

Results: From 01 January 2015 to 31 August 2019, 98 patients were enrolled in the study. There were 219 RLS with 245 CRLM. The surgeon registered positive RM (RM+) of <1mm in 41 (18.7%) RLS. Taking the result of the histopathological assessment (HPA) as the “gold standard”, it was determined that RM was true positive in 32 (14.6%) cases. False positive RM was found in 9 (4.1%) cases. False negative RM was found in 20 (9.1%) cases. True negative RM was found in 158 (72.2%) cases. Sensitivity of surgical assessment (SA) of RM+ was 61.5% (32/52). Specificity of SA of RM+ was 94.6% (158/167). The positive predictive value (PPV) was 78.0% (32/41), while the negative predictive value (NPV) was 88.8% (158/178). The overall accuracy of the RM+ SA was 86.8% (190/219). There was no statistically significant difference in the assessment of RM+ per RLS by surgeon and pathologists (p=0.061), but it was significant when analyses per patients was performed (p=0.017). Recurrence rate for RM+ patients was 48.1% (13/27, p=0.05) for SA and 35.0% (14/40, p=0.17) for HPA. Three year DFS for RM- and RM+ was 66.5% and 27.9% (p=0.04), respectively, by SA, and 64.8% and 42.1% (p=0.106), respectively, by HPA.

Conclusion: Intraoperative assessment of RM- by surgeon of RLS is clinically meaningful. There is not a statistically significant difference in the assessment of RM+ by surgeon and pathologists per RLS, but it was statically significant on a per patient basis. RM determined by surgeon has better prognostic impact on recurrence rate and 1- and 3-year DFS than standard histopathological assessment.

CBCT-based navigation system for open liver surgery: Accurate guidance toward mobile and deformable targets with a semi-rigid organ approximation and electromagnetic tracking of the liver

Purpose

The surgical navigation system that provides guidance throughout the surgery can facilitate safer and more radical liver resections, but such a system should also be able to handle organ motion. This work investigates the accuracy of intraoperative surgical guidance during open liver resection, with a semi‐rigid organ approximation and electromagnetic tracking of the target area.

Methods

The suggested navigation technique incorporates a preoperative 3D liver model based on diagnostic 4D MRI scan, intraoperative contrast‐enhanced CBCT imaging and electromagnetic (EM) tracking of the liver surface, as well as surgical instruments, by means of six degrees‐of‐freedom micro‐EM sensors.

Results

The system was evaluated during surgeries with 35 patients and resulted in an accurate and intuitive real‐time visualization of liver anatomy and tumor's location, confirmed by intraoperative checks on visible anatomical landmarks. Based on accuracy measurements verified by intraoperative CBCT, the system’s average accuracy was 4.0 ± 3.0 mm, while the total surgical delay due to navigation stayed below 20 min.

Conclusions

The electromagnetic navigation system for open liver surgery developed in this work allows for accurate localization of liver lesions and critical anatomical structures surrounding the resection area, even when the liver was manipulated. However, further clinically integrating the method requires shortening the guidance‐related surgical delay, which can be achieved by shifting to faster intraoperative imaging like ultrasound. Our approach is adaptable to navigation on other mobile and deformable organs, and therefore may benefit various clinical applications.

Evaluation of a novel navigation platform for laparoscopic liver surgery with organ deformation compensation using injected fiducials

In laparoscopic liver resection, surgeons conventionally rely on anatomical landmarks detected through a laparoscope, preoperative volumetric images and laparoscopic ultrasound to compensate for the challenges of minimally invasive access. Image guidance using optical tracking and registration procedures is a promising tool, although often undermined by its inaccuracy. This study evaluates a novel surgical navigation solution that can compensate for liver deformations using an accurate and effective registration method. The proposed solution relies on a robotic C-arm to perform registration to preoperative CT/MRI image data and allows for intraoperative updates during resection using fluoroscopic images. Navigation is offered both as a 3D liver model with real-time instrument visualization, as well as an augmented reality overlay on the laparoscope camera view. Testing was conducted through a pre-clinical trial which included four porcine models. Accuracy of the navigation system was measured through two evaluation methods: liver surface fiducials reprojection and a comparison between planned and navigated resection margins. Target Registration Error with the fiducials evaluation shows that the accuracy in the vicinity of the lesion was 3.78±1.89 mm. Resection margin evaluations resulted in an overall median accuracy of 4.44 mm with a maximum error of 9.75 mm over the four subjects. The presented solution is accurate enough to be potentially clinically beneficial for surgical guidance in laparoscopic liver surgery.

Intraoperative detection of colorectal and pancreatic liver metastases using SGM-101, a fluorescent antibody targeting CEA

BACKGROUND

Fluorescence-guided surgery can provide surgeons with an imaging tool for real-time intraoperative tumor detection. SGM-101, an anti-CEA antibody labelled with a fluorescent dye, is a tumor-specific imaging agent that can aid in improving detection and complete resection for CEA-positive tumors. In this study, the performance of SGM-101 for the detection of colorectal and pancreatic liver metastases was investigated.

METHODS

In this open-label, non-randomized, single-arm pilot study, patients were included with liver metastases from colorectal origin and intraoperatively detected liver metastases from pancreatic origin (during planned pancreatic surgery). SGM-101 was administered two to four days before the scheduled surgery as a single intravenous injection. Intraoperative fluorescence imaging was performed using the Quest Spectrum® imaging system. The performance of SGM-101 was assessed by measuring the intraoperative fluorescence signal and comparing this to histopathology.

RESULTS

A total of 19 lesions were found in 11 patients, which were all suspected as malignant in white light and subsequent fluorescence inspection. Seventeen lesions were malignant with a mean tumor-to-background ratio of 1.7. The remaining two lesions were false-positives as proven by histology.

CONCLUSION

CEA-targeted fluorescence-guided intraoperative tumor detection with SGM-101 is feasible for the detection of colorectal and pancreatic liver metastases.

Impact of resection margins for colorectal liver metastases in laparoscopic and open liver resection: a propensity score analysis

BACKGROUND

There is no clear consensus over the optimal width of resection margin for colorectal liver metastases (CRLM), with evolving definitions alongside the advances on the management of the disease. In addition, data on the impact of resection margin after laparoscopic liver resection are still scarce.

METHODS

Prospectively maintained databases of patients undergoing open or laparoscopic CRLM resection in 7 European tertiary hepatobiliary referral centres were reviewed. After propensity score matching (PSM), the influence of 1 mm and wider margins on OS and DFS were evaluated in open and laparoscopic cohorts.

RESULTS

After PSM, 648 patients were comparable in each group. The incidence of positive margins (< 1 mm) was similar in open and laparoscopic groups (17% vs 13%, p = 0,142). Margins < 1 mm were associated with shorter RFS in open (12 vs 26 months, p = 0.042) and in laparoscopic group (13 vs 23, p = 0,002). Margins < 1 mm were associated with shorter OS in open (36 vs 57 months, p = 0.027), but not in laparoscopic group (49 vs 60, p = 0,177). Subgroups with margins ≥ 1 mm (1-4 mm, 5-9 mm, ≥ 10 mm) presented similar RFS in open (p = 0,251) or laparoscopic cohorts (p = 0.117), as well as similar OS in open (p = 0.295) or laparoscopic cohorts (p = 0.908). In the presence of liver recurrence, repeat liver resection was performed in 70 (30%) patients in the open group and 88 (48%) in the laparoscopic group (p < 0.001).

CONCLUSIONS

Our study suggests that a positive resection margin (less than 1 mm) width does not impact OS after laparoscopic resection of CRLMs as it does in open liver resection. However, a positive margin continues to affect RFS in open and laparoscopic resection. Wider margins than 1 mm do not seem to improve oncological results in open or laparoscopic surgery.

Laparoscopic liver resection for liver tumours in proximity to major vasculature: A single-center comparative study

BACKGROUND

With growing popularity and experience in laparoscopic liver surgery, the options for more difficult procedures increase. Only small case series have been published regarding laparoscopic liver resection (LLR) for tumours in proximity to major vessels (MVs). The aim was to compare outcomes of LLR for tumours located less or more than 15 mm from MVs.

METHODS

This was a retrospective analysis of a prospectively collected database of consecutive LLR (October 2011-August 2017). Proximity to MVs (PMV) was defined as lesions located within 15 mm to the caval vein, hepatic veins and portal vein (main trunk and first branches). The control group were all lesions located more than 15 mm from MVs.

RESULTS

Some 60/235 LLR were performed for lesions in proximity to major vasculature (24%). In the PMV group, median IWATE Difficulty Score was higher (8.5 (IQR: 6.0-9.0) VS 5.0 (IQR: 3.0-6.0), p < 0.001) as was the use of CUSA® (45.0% VS 8.6%, p < 0.001) and Pringle manoeuvre (8.3% VS 1.7%; p = 0.028). Operative time was longer (180min (IQR: 140-210) VS 120min (IQR: 75-150), p < 0.001) and blood loss was higher (190 ml (IQR: 100-325) VS 75 ml (IQR: 50-220), p < 0.001) in the PMV group. There was no difference in perioperative blood transfusion (3.3% VS 1.7%, p = 0.60) or postoperative morbidity (15.0% VS 14.3%, p = 0.89). There was no mortality in both groups. On mean follow-up of 21 months, no significant differences could be found in disease free (p = 0.77) and overall survival (p = 0.12).

CONCLUSION

In experienced hands, LLR of lesions in proximity to MVs is safe and feasible with acceptable short and long-term results.

Laparoscopic liver resection for non-colorectal non-neuroendocrine metastases: perioperative and oncologic outcomes

BACKGROUND

Liver resection is a treatment of choice for colorectal and neuroendocrine liver metastases, and laparoscopy is an accepted approach for surgical treatment of these patients. The role of liver resection for patients with non-colorectal non-neuroendocrine liver metastases (NCNNLM), however, is still disputable. Outcomes of laparoscopic liver resection for this group of patients have not been analyzed.

MATERIAL AND METHODS

In this retrospective study, patients who underwent laparoscopic liver resection for NCNNLM at Oslo University Hospital between April 2000 and January 2018 were analyzed. Perioperative and oncologic data of these patients were examined. Postoperative morbidity was classified using the Accordion classification. Kaplan-Meier method was used for survival analysis. Median follow-up was 26 (IQR, 12-41) months.

RESULTS

Fifty-one patients were identified from a prospectively collected database. The histology of primary tumors was classified as adenocarcinoma (n = 16), sarcoma (n = 4), squamous cell carcinoma (n = 4), melanoma (n = 16), gastrointestinal stromal tumor (n = 9), and adrenocortical carcinoma (n = 2). The median operative time was 147 (IQR, 95-225) min, while the median blood loss was 200 (IQR, 50-500) ml. Nine (18%) patients experienced postoperative complications. There was no 90-day mortality in this study. Thirty-five (68%) patients developed disease recurrence or progression. Seven (14%) patients underwent repeat surgical procedure for recurrent liver metastases. One-, three-, and five-year overall survival rates were 85%, 52%, and 38%, respectively. The median overall survival was 37 (95%CI, 25 to 49) months.

CONCLUSION

Laparoscopic liver resection for NCNNLM results in good outcomes and should be considered in patients selected for surgical treatment.

Quality of life from a randomized trial of laparoscopic or open liver resection for colorectal liver metastases

Background

Most treatments for cancer cause a decline in patients' health-related quality of life (HRQoL). Limiting this decline is a universal goal for healthcare providers. Using minimally invasive instead of open surgical techniques might be one way to achieve this. The aim of this study was to compare postoperative HRQoL after open and laparoscopic liver resection.

Methods

This was a predefined substudy of an RCT comparing open with laparoscopic liver resection. Patients with colorectal liver metastases were assigned randomly to open or laparoscopic parenchyma-sparing liver resection. HRQoL was assessed with the Short Form 36 questionnaire at baseline, and 1 and 4 months after surgery.

Results

A total of 280 patients were randomized, of whom 273 underwent surgery (129 laparoscopic, 144 open); 682 questionnaires (83.3 per cent) were available for analysis. One month after surgery, patients in the laparoscopic surgery group reported reduced scores in two HRQoL domains (physical functioning and role physical), whereas those in the open surgery group reported reduced scores in five domains (physical functioning, role physical, bodily pain, vitality and social functioning). Four months after surgery, HRQoL scores in the laparoscopic group had returned to preoperative levels, whereas patients in the open group reported reduced scores for two domains (role physical and general health). The between-group difference was statistically significant in favour of laparoscopy for four domains after 1 month (role physical, bodily pain, vitality and social functioning) and for one domain after 4 months (role physical).

Conclusion

Patients assigned to laparoscopic liver surgery reported better postoperative HRQoL than those assigned to open liver surgery. For role limitations caused by physical health problems, patients in the laparoscopic group reported better scores up to 4 months after surgery. Registration number: NCT01516710 (http://www.clinicaltrials.gov).

Sub-millimeter surgical margin is acceptable in patients with good tumor biology after liver resection for colorectal liver metastases

BACKGROUND

The definition of R1 resection in colorectal cancer liver metastases (CRLM) remains debatable. This retrospective study was conducted to clarify the impact of R1 margin on patient survival after liver resection for CRLM, taking into consideration tumor biology, including RAS status and chemotherapy response.

METHODS

We retrospectively analysed the clinical and survival data of 214 CRLM patients with initially resectable liver metastases who underwent liver resection after receiving neoadjuvant chemotherapy between January 2006 and December 2016.

RESULTS

R1 resection significantly impacted patients' overall survival (OS) and disease-free survival (DFS) in the overall patient cohort (5-year OS: 53.2% for R0 vs 38.2% for R1, P = 0.001; 5-year DFS: 26.5% for R0 vs 10.5% for R1, P = 0.002). In the RAS wild-type subgroup and respond to chemotherapy (RC) subgroup, R1 reached a similar OS to those who underwent R0 resection (RAS wild-type, P = 0.223; RC, P = 0.088). For the RAS mutated subgroup and no response to chemotherapy (NRC) subgroup, OS was significantly worse underwent R1 resection (RAS mutant, P = 0.002; NRC, P = 0.022). When considering tumor biology combining RAS and chemotherapy response status, R1 resection was only acceptable in patients with both RAS wild-type and RC (5-year OS: 66.4% for R0 vs 65.2% for R1, p = 0.884), but was significantly worse in those with either RAS mutation or NRC.

CONCLUSIONS

Tumor biology plays an important role in deciding the appropriate resection margin in patients with CRLM undergoing radical surgery. R1 resection margin is only acceptable in RAS wild-type patients who respond to chemotherapy.

Laparoscopic Versus Open Resection for Colorectal Liver Metastases: The OSLO-COMET Randomized Controlled Trial

OBJECTIVE

To perform the first randomized controlled trial to compare laparoscopic and open liver resection.

SUMMARY BACKGROUND DATA

Laparoscopic liver resection is increasingly used for the surgical treatment of liver tumors. However, high-level evidence to conclude that laparoscopic liver resection is superior to open liver resection is lacking.

METHODS

Explanatory, assessor-blinded, single center, randomized superiority trial recruiting patients from Oslo University Hospital, Oslo, Norway from February 2012 to January 2016. A total of 280 patients with resectable liver metastases from colorectal cancer were randomly assigned to undergo laparoscopic (n = 133) or open (n = 147) parenchyma-sparing liver resection. The primary outcome was postoperative complications within 30 days (Accordion grade 2 or higher). Secondary outcomes included cost-effectiveness, postoperative hospital stay, blood loss, operation time, and resection margins.

RESULTS

The postoperative complication rate was 19% in the laparoscopic-surgery group and 31% in the open-surgery group (12 percentage points difference [95% confidence interval 1.67-21.8; P = 0.021]). The postoperative hospital stay was shorter for laparoscopic surgery (53 vs 96 hours, P < 0.001), whereas there were no differences in blood loss, operation time, and resection margins. Mortality at 90 days did not differ significantly from the laparoscopic group (0 patients) to the open group (1 patient). In a 4-month perspective, the costs were equal, whereas patients in the laparoscopic-surgery group gained 0.011 quality-adjusted life years compared to patients in the open-surgery group (P = 0.001).

CONCLUSIONS

In patients undergoing parenchyma-sparing liver resection for colorectal metastases, laparoscopic surgery was associated with significantly less postoperative complications compared to open surgery. Laparoscopic resection was cost-effective compared to open resection with a 67% probability. The rate of free resection margins was the same in both groups. Our results support the continued implementation of laparoscopic liver resection.

Simultaneous Pure Laparoscopic Resection of Primary Colorectal Cancer and Synchronous Liver Metastases: A Single Institution Experience with Propensity Score Matching Analysis

Background

The aim of the study was to compare the outcome of pure laparoscopic and open simultaneous resection of both the primary colorectal cancer and synchronous colorectal liver metastases (SCLM).

Patients and methods

From 2000 to 2016 all patients treated by simultaneous resection were assessed for entry in this single center, clinically nonrandomized trial. A propensity score matching was used to compare the laparoscopic group (LAP) to open surgery group (OPEN). Primary endpoints were perioperative and oncologic outcomes. Secondary endpoints were overall survival (OS) and disease-free survival (DFS).

Results

Of the 82 patients identified who underwent simultaneous liver resection for SCLM, 10 patients underwent LAP. All these consecutive patients from LAP were matched to 10 comparable OPEN. LAP reduced the length of hospital stay (P = 0.044) and solid food oral intake was faster (P = 0.006) in this group. No patient undergoing the laparoscopic procedure experienced conversion to the open technique. No difference was observed in operative time, blood loss, transfusion rate, narcotics requirement, clinical risk score, resection margin, R0 resections rate, morbidity, mortality and incisional hernias rate. The two groups did not differ significantly in terms of the 3-year OS rate (90 vs. 75%; P = 0.842) and DFS rate (60 vs. 57%; P = 0.724).

Conclusions

LAP reduced the length of hospital stay and offers faster solid food oral intake. Comparable oncologic and survival outcomes can be achieved. LAP is beneficial for well selected patients in high volume centers with appropriate expertise.

Laparoscopic Parenchyma-sparing Liver Resection for Colorectal Metastases

Background

Laparoscopic liver resection (LLR) of colorectal liver metastases (CLM) is increasingly performed in specialized centers. While there is a trend towards a parenchyma-sparing strategy in multimodal treatment for CLM, its role is yet unclear. In this study we present short- and long-term outcomes of laparoscopic parenchyma-sparing liver resection (LPSLR) at a single center.

Patients and methods

LLR were performed in 951 procedures between August 1998 and March 2017 at Oslo University Hospital, Oslo, Norway. Patients who primarily underwent LPSLR for CLM were included in the study. LPSLR was defined as non-anatomic hence the patients who underwent hemihepatectomy and sectionectomy were excluded. Perioperative and oncologic outcomes were analyzed. The Accordion classification was used to grade postoperative complications. The median follow-up was 40 months.

Results

296 patients underwent primary LPSLR for CLM. A single specimen was resected in 204 cases, multiple resections were performed in 92 cases. 5 laparoscopic operations were converted to open. The median operative time was 134 minutes, blood loss was 200 ml and hospital stay was 3 days. There was no 90-day mortality in this study. The postoperative complication rate was 14.5%. 189 patients developed disease recurrence. Recurrence in the liver occurred in 146 patients (49%), of whom 85 patients underwent repeated surgical treatment (liver resection [n = 69], ablation [n = 14] and liver transplantation [n = 2]). Five-year overall survival was 48%, median overall survival was 56 months.

Conclusions

LPSLR of CLM can be performed safely with the good surgical and oncological results. The technique facilitates repeated surgical treatment, which may improve survival for patients with CLM.

Laparoscopic liver resection for metastatic melanoma

BACKGROUND

Stage IV metastatic melanoma carries a poor prognosis. In the case of melanoma liver metastasis (MLM), surgical resection may improve survival and represents a therapeutic option, with varying levels of success. Laparoscopic liver resection (LLR) for metastatic melanoma is poorly studied. The aim of this study was to analyze the outcomes of LLR in patients with MLM.

MATERIALS AND METHODS

Between April 2000 and August 2013, 11 (1 cutaneous, 9 ocular and 1 unknown primary) patients underwent LLR for MLM at Oslo University Hospital-Rikshospitalet and 13 procedures in total were carried out. Perioperative and oncologic outcomes were analyzed. Postoperative morbidity was classified using the Accordion classification. Kaplan-Meier method was used for survival analysis.

RESULTS

A total of 23 liver specimens were resected. The median operative time was 137 (65-470) min, while the median blood loss was less than 50 (<50-900) ml. No intraoperative unfavorable incidents and 30-day mortality occurred. Median follow-up was 33 (9-92) months. Ten patients (91%) developed recurrence within a median of 5 months (2-18 months) and two patients underwent repeat LLR for recurrent liver metastases. One-, three-, and five-year overall survival rates were 82, 45 and 9%, respectively. The median overall survival was 30 (9-92) months.

CONCLUSION

Perioperative morbidity and long-term survival after LLR for MLM seems to be comparable to open liver resection. Thus, LLR may be preferred over open liver resection due to the well-known advantages of laparoscopy, such as reduced pain and improved possibility for repeated resections.

Recurrence of Hepatocellular Carcinoma After Laparoscopic Hepatectomy: Risk Factors and Treatment Strategies

PURPOSE

To investigate the risk factors for recurrence and treatment strategies after patients with hepatocellular carcinoma (HCC) undergo total laparoscopic hepatectomy (LH).

METHODS

The study included 109 patients who underwent LH (laparoscopy resection [LR] group, n = 50) or open hepatectomy [OH] (open resection [OR] group, n = 59) for HCC in our hospital between March 2011 and June 2016. Perioperative outcomes, disease recurrence, survival, and risk factors for recurrence were analyzed.

RESULTS

Patient characteristics did not significantly differ between groups. The 1- and 3-year survival rates were 90.7% and 78.1%, respectively, for the LR group and 83.1% and 74.4%, respectively, for the OR group (P = .71). The 1- and 3-year disease-free survival rates were 89.6% and 51.4%, respectively, for the LR group and 84.7% and 59.6%, respectively, for the OR group (P = .935). Tumor size, differentiation, vascular invasion, surgical bleeding, and surgical resection margin were risk factors for tumor recurrence after LH.

CONCLUSION

LH for HCC did not increase the risk of recurrence compared with OH. Tumor size, differentiation, vascular invasion, surgical bleeding, and surgical resection margin were risk factors for tumor recurrence. Reducing bleeding during surgery and ensuring sufficient surgical margins were the most important measures to reduce postoperative recurrence of HCC.

Outcome after laparoscopic and open resections of posterosuperior segments of the liver

BACKGROUND

Laparoscopic resection of posterosuperior (PS) segments of the liver is hindered by limited visualization and curvilinear resection planes. The aim of this study was to compare outcomes after open and laparoscopic liver resections of PS segments.

METHODS

Patients who underwent minor open liver resection (OLR) and laparoscopic liver resection (LLR) between 2006 and 2014 were identified from the institutional databases of seven tertiary referral European hepatobiliary surgical units. Propensity score-matched analysis was used to match groups for known confounders. Perioperative outcomes including complications were assessed using the Dindo-Clavien classification, and the comprehensive complication index was calculated. Survival was analysed with the Kaplan-Meier method.

RESULTS

Some 170 patients underwent OLR and 148 had LLR. After propensity score-matched analysis, 86 patients remained in both groups. Overall postoperative complication rates were significantly higher after OLR compared with LLR: 28 versus 14 per cent respectively (P = 0·039). The mean(s.d.) comprehensive complication index was higher in the OLR group, although the difference was not statistically significant (26·7(16·6) versus 18·3(8·0) in the LLR group; P = 0·108). The mean(s.d.) duration of required analgesia and the median (range) duration of postoperative hospital stay were significantly shorter in the LLR group: 3·0(1·1) days versus 1·6(0·8) days in the OLR group (P < 0·001), and 6 (3-44) versus 4 (1-11) days (P < 0·001), respectively. The 3-year recurrence-free survival rates for patients with hepatocellular carcinoma (37 per cent for OLR versus 30 per cent for LLR; P = 0·534) and those with colorectal liver metastases (36 versus 36 per cent respectively; P = 0·440) were not significantly different between the groups.

CONCLUSION

LLR of tumours in PS segments is feasible in selected patients. LLR is associated with fewer complications and does not compromise survival compared with OLR.

Totally laparoscopic liver resection for colorectal metastasis located in Segment 7 in a patient with situs inversus totalis

Situs inversus totalis (SIT) is a congenital condition consisting of a mirror image of transposition of the abdominal and thoracic organs occurring in about 1:5000 to 1:10 000 adults. We report on a 60-year-old male with a single colorectal liver metastasis in the Segment 7. The patients underwent a totally laparoscopic sub-segmentectomy. Intraoperative approach on a reverse posterior segment was difficult because of left-sided position of the liver. Postoperative course was uneventful and the patient was discharged after 5 days. To our knowledge, only a few cases of open liver resections in patients with SIT have been published. This is, therefore, the first case of laparoscopic liver resection for colorectal liver metastasis in a patient with SIT. We provide the readers with useful tips to perform minimally invasive liver surgery in such patients.

KRAS Mutation Status Dictates Optimal Surgical Margin Width in Patients Undergoing Resection of Colorectal Liver Metastases

BACKGROUND

The optimal tumor-free margin width remains controversial and may be inappropriate to investigate without considering differences in the underlying tumor biology.

METHODS

R1 resection was defined as margin clearance less than 1 mm. R0 resection was further divided into 3 groups: 1-4, 5-9, and ≥10 mm. The impact of margin width on overall survival (OS) relative to KRAS status [wild type (wtKRAS) vs. mutated (mutKRAS)] was assessed.

RESULTS

A total of 411 patients met inclusion criteria. Median patient age was 58 years (interquartile range, 49.7-66.7); most patients were male (n = 250; 60.8 %). With a median follow-up of 28.3 months, median and 5-year OS were 69.8 months and 55.1 %. Among patients with wtKRAS tumors, although margin clearance of 1-4 mm or more was associated with improved OS compared to R1 (all P < 0.05), no difference in OS was observed when comparing margin clearance of 1-4 mm to the 5-9 mm and the ≥10 mm groups (all P > 0.05). In contrast, among patients with mutKRAS tumors, all three groups of margin clearance (1-4, 5-9, and ≥10 mm) fared no better in terms of 5-year survival compared to R1 resection (all P > 0.05).

CONCLUSIONS

While a 1-4 mm margin clearance in patients with wtKRAS tumors was associated with improved survival, wider resection width did not confer an additional survival benefit. In contrast, margin status-including a 1 cm margin-did not improve survival among patients with mutKRAS tumors.

Validation of clinical risk scores for laparoscopic liver resections of colorectal liver metastases: A 10-year observed follow-up study

OBJECTIVE

The aim of this study was to validate clinical risk scores in patients underwent laparoscopic resection of colorectal liver metastases (CLM) with 5 years follow-up or more, and assess 5- and 10-year actual survival in this group.

METHODS

A total of 516 laparoscopic liver resections were performed in 406 patients with CLM between February 1998 and September 2015. A follow-up of 5 and 10 years could be assessed in 144 and 29 patients, respectively. The Fong score, pre- and postoperative Basingstoke Predictive Index (BPI), Nordlinger score, and Iwatsuki score were validated.

RESULTS

Five- and ten-year cancer-related actual survival was 54% and 32%, respectively. The Fong score, pre- and postoperative BPI and the Nordlinger score divided patients into risk groups with significant difference in survival between the groups. However, predicted 5-year survival rates were lower than the actual 5-year survival (mean difference in 17%,13%, 20%, and 30%, respectively).

CONCLUSION

The Fong score, pre- and postoperative BPI and the Nordlinger score systems can be used to predict survival for laparoscopically operated patients in the era of multimodal-treatment after adjusting of survival rates. The actual five- and 10-year survival after laparoscopic resection of CLM is similar to results previously published for open liver resection. J. Surg. Oncol. 2016;114:757-763. © 2016 Wiley Periodicals, Inc.

Weighted gene co-expression network analysis of colorectal cancer liver metastasis genome sequencing data and screening of anti-metastasis drugs

Approximately 9% of cancer-related deaths are caused by colorectal cancer (CRC). CRC patients are prone to liver metastasis, which is the most important cause for the high CRC mortality rate. Understanding the molecular mechanism of CRC liver metastasis could help us to find novel targets for the effective treatment of this deadly disease. Using weighted gene co-expression network analysis on the sequencing data of CRC with and with metastasis, we identified 5 colorectal cancer liver metastasis related modules which were labeled as brown, blue, grey, yellow and turquoise. In the brown module, which represents the metastatic tumor in the liver, gene ontology (GO) analysis revealed functions including the G-protein coupled receptor protein signaling pathway, epithelial cell differentiation and cell surface receptor linked signal transduction. In the blue module, which represents the primary CRC that has metastasized, GO analysis showed that the genes were mainly enriched in GO terms including G-protein coupled receptor protein signaling pathway, cell surface receptor linked signal transduction, and negative regulation of cell differentiation. In the yellow and turquoise modules, which represent the primary non-metastatic CRC, 13 downregulated CRC liver metastasis-related candidate miRNAs were identified (e.g. hsa-miR-204, hsa-miR-455, etc.). Furthermore, analyzing the DrugBank database and mining the literature identified 25 and 12 candidate drugs that could potentially block the metastatic processes of the primary tumor and inhibit the progression of metastatic tumors in the liver, respectively. Data generated from this study not only furthers our understanding of the genetic alterations that drive the metastatic process, but also guides the development of molecular-targeted therapy of colorectal cancer liver metastasis.

Laparoscopic Right Hepatectomy by the Caudal Approach Versus Conventional Approach: A Comparative Study

BACKGROUND

Laparoscopic right hepatectomy (LRH) is increasingly performed for the treatment of many liver diseases. However, it remains a challenging procedure and is limited to highly specialized centers. Increasing the safety and efficacy of LRH is crucial. This study evaluated the safety and feasibility of the novel caudal approach (CDA) in LRH and in comparison with the conventional approach (CA).

METHODS

Of a total of 40 patients who underwent LRH between June 2007 and July 2015 at our center, 10 cases underwent the CDA, while 30 underwent the CA. Operative and postoperative outcomes were analyzed.

RESULTS

Clinical data and patient characteristics were comparable between the two groups. Only 1 patient required a laparoscopic-assisted procedure in the CDA group, while 14 patients were converted to laparotomy (n = 10) or laparoscopic-assisted procedures (n = 4) in the CA group, although the difference did not reach statistical significance (P = .060). However, the difference in conversion to laparotomy between the two groups was significant (P = .043). In addition, when considering 23 patients with malignancies, the median surgical margin was significantly greater in the CDA group (n = 6) (20 mm versus 10 mm; P = .023) than in the CA group (n = 17). Other operative and postoperative outcomes were similar between the two groups.

CONCLUSIONS

The CDA achieves safety and feasibility similar to that of the CA in LRH and requires relatively less conversion to laparotomy. In selected patients, the CDA offers an alternative option to the CA for LRH in experienced hands. Further studies with larger samples are warranted to evaluate the CDA.

Impact of surgical margin clearance for resection of secondary hepatic malignancies

Over the past several decades, there has been increasing discussion regarding the optimal management of secondary liver malignancies. Traditionally, resection has only been recommended if it could be accomplished with negative microscopic margins of at least 10 mm. However, many investigators have pushed this limit to offer resection to patients with narrower margins. We review the data regarding the impact of margin clearance on outcomes for patients undergoing hepatic metastasectomy.

Oncological safety of ultrasound-guided laparoscopic liver resection for colorectal metastases: a case-control study

Laparoscopic liver surgery has gained widespread acceptance and nowadays it is suggested even for malignant disease. Although the benefits on short-term outcomes have been proven, data on oncological safety are still lacking. The aim of this study is to assess oncologic results after ultrasound-guided laparoscopic liver resection (LLR) or open liver resection (OLR) for colorectal metastases. 37 consecutive patients undergoing LLR between 01/2004 and 03/2014 were matched at a ratio of 1:1 with 37 OLR. Matching criteria were male sex, number and diameter of liver metastases, segment location, synchronous presentation, site and stage of primary tumor, positive lymph nodes of the primary, and concomitant extrahepatic disease. Demographic characteristics were similar among groups. Parenchymal transection time was longer in the LLR group (68 ± 38.2 SD vs 40 ± 33.7 SD, p = 0.01). Mortality was nil in LLR and OLR. Overall morbidity was significantly lower in LLR (13.5 vs 37.8%, p = 0.02), although severe complications were similar among the two groups. Patients undergoing LLR were discharged earlier (5 ± 2.3 SD vs 8 ± 6.6 SD days, p < 0.001). The median margin width was 5 (0-40) mm in LLR vs 8 (0-25) mm in OLR, p = 0.897. R1 resection was recorded in four LLR and three OLR (p = 1). Overall recurrences were similar among groups. Eight patients with hepatic or extrahepatic recurrence among LLR underwent surgery vs four of OLR (p = 0.03). After a median follow-up of 35.7 months in LLR and 47.9 months in OLR, 3-year overall survival was 91.8% LLR and 74.8% OLR (p = 0.14). 3-year disease-free survival was 69.1% LLR and 65.9% OLR (p = 0.53). Multivariate analysis showed that postoperative complications [HR 3.42 (95% CI 1.32-8.89)] and multiple metastases [HR 3.84 (95% CI 1.34-10.83)] were independent predictors of worse survival (p = 0.01). Ultrasound-LLR for colorectal hepatic metastases is safe, ensuring oncologic outcomes comparable to OLR.

Segmentectomy: is minimally invasive surgery going to change a liver dogma?

Nowadays, the respective approach to hepatic resections (for malignant or benign liver lesions) is oriented toward minimal parenchymal resection. This surgical behavior is sustained by several observations that surgical margin width is not correlated with recurrence of malignancies. Parenchymal-sparing resection reduces morbidity without changing long-term results and allows the possibility of re-do liver resection in case of recurrence. Minimally invasive liver surgery (MILS) is performed worldwide and is considered a standard of care for many surgical procedures. MILS is associated with less blood loss, less analgesic requirements, and shorter length of hospital with a better quality of life. One of the more frequent criticisms to MILS is that it represents a more challenging approach for anatomical segmentectomies and that in most cases a non-anatomical resection could be performed with thinner resection margins compared with open surgery. But even in the presence of reduced surgical margins, oncological results in the short- and long-term follow-up seem to be the same such as open surgery. The purpose of this review is to try to understand whether chasing at any cost laparoscopic anatomical segmentectomies is still necessary whereas non-anatomical resections, with a parenchymal-sparing behavior, are feasible and overall recommended also in a laparoscopic approach. The message coming from this review is that MILS is opening more and more new frontiers that are still need to be supported by further experience.

Total abdominal approach for postero-superior segments (7, 8) in laparoscopic liver surgery: a multicentric experience

Laparoscopic liver resections are frequently performed for peripheral lesions located in the antero-inferior segments. Resection of postero-superior segments is more demanding and dangerous than other segmentectomies, resulting in a longer operation time and increased blood loss. To reduce technical challenges, some authors advocated a modified surgical approach for these segments with the patient placed in the left lateral decubitus with the right arm suspended and suggested technical variations like the use of an additional intercostal trocar, the placement of one or two additional trans-thoracic trocars, a hand-assisted approach or a hybrid method with a median laparotomy. In the present series of 88 patients from four hepatobiliary centers with high volume of activity in Italy, a standard lithotomic position has been routinely used without the need for left lateral decubitus or semi-prone position and through abdominal wall without use of trans-thoracic trocars. This approach allows a more comfortable use of the Pringle maneuver that we used routinely in hepatic resection for PS segments; and, a very short time is needed for conversion, whenever it is required. In our series, laparoscopic resection of liver tumors located in the postero-superior segments of the liver with a total abdominal approach is technically feasible and safe with short-term results similar to other laparoscopic liver resections.

Open versus laparoscopic liver resection for colorectal liver metastases (the Oslo-CoMet Study): study protocol for a randomized controlled trial

BACKGROUND

Laparoscopic liver resection is used in specialized centers all over the world. However, laparoscopic liver resection has never been compared with open liver resection in a prospective, randomized trial.

METHODS/DESIGN

The Oslo-CoMet Study is a randomized trial into laparoscopic versus open liver resection for the surgical management of hepatic colorectal metastases. The primary outcome is 30-day perioperative morbidity. Secondary outcomes include 5-year survival (overall, disease-free and recurrence-free), resection margins, recurrence pattern, postoperative pain, health-related quality of life, and evaluation of the inflammatory response. A cost-utility analysis of replacing open surgery with laparoscopic surgery will also be performed. The study includes all resections for colorectal liver metastases, except formal hemihepatectomies, resections where reconstruction of vessels/bile ducts is necessary and resections that need to be combined with ablation. All patients will participate in an enhanced recovery after surgery program. A biobank of liver and tumor tissue will be established and molecular analysis will be performed.

DISCUSSION

After 35 months of recruitment, 200 patients have been included in the trial. Molecular and immunology data are being analyzed. Results for primary and secondary outcome measures will be presented following the conclusion of the study (late 2015). The Oslo-CoMet Study will provide the first level 1 evidence on the benefits of laparoscopic liver resection for colorectal liver metastases.

TRIAL REGISTRATION

The trial was registered in ClinicalTrals.gov (NCT01516710) on 19 January 2012.

Impact of surgical margins on overall and recurrence-free survival in parenchymal-sparing laparoscopic liver resections of colorectal metastases

BACKGROUND

The relationship between the width of surgical margins and local and distant recurrence of colorectal liver metastases (CRLM) remain controversial. We analyzed the impact of surgical margins in laparoscopic liver resections (LLR) for CRLM, using the parenchymal-sparing approach on overall (OS) and recurrence-free survival (RFS).

METHODS

From January 2005 to October 2012, 114 first LLR for CRLM were performed and retrospectively analyzed. The ultrasonic aspirator was used for parenchyma division. R1 margins were defined when the tissue width was <1 mm.

RESULTS

After a mean follow-up of 30.9 ± 1.71 months, OS was 97.1-73.9-58.9% and the RFS 64.2-35.2-31% at 1-3-5 years, respectively. The major resection rate was 7%. The median margin width was 3 (0-40) mm, and R1 resection was recorded in 14 (12.3%) cases. Twenty-two patients (33.3%) with hepatic recurrence underwent a repeat hepatectomy. R1 margins were significantly related to lower RFS survival (p = 0.038) but did not affect OS. Multivariate analysis showed that lesions located in postero-superior segments (HR = 2.4, 95% CI 1.24-4.61, p = 0.009) as well as blood loss (HR = 3.2, 95% CI 1.23-7.99, p = 0.012) were independent risk factors for tumor recurrence. The carcinoembryonic antigen level >10 mcg/L affected OS (HR = 4.2 95% CI 2.02-16.9, p = 0.001), and the resection of more than two tumors was significantly associated with R1 margins (HR = 9.32, 95% CI 1.14-32.5, p = 0.037).

DISCUSSION

Laparoscopic parenchymal-sparing surgery of CRLM does not compromise the oncological outcome, allowing a higher percentage of repeat hepatectomy. R1 margins are a risk factor for tumor recurrence but not for overall survival. The presence of multiple lesions is the only independent risk factor of R1 margins and also the major disadvantage of this technique.