Early experience with pure laparoscopic donor hepatectomy: comparison with open donor hepatectomy and non-donor laparoscopic hepatectomy.

BACKGROUND: Pure laparoscopic donor hepatectomy (L-DH) has seen a rise in uptake in recent years following the popularization of minimally invasive modality for major hepatobiliary surgery. Our study aimed to determine the safety and compare the perioperative outcomes of L-DH with open donor hepatectomy (O-DH) and laparoscopic non donor hepatectomy (L-NDH) based on our single institution experience. METHODS: Eighty of 113 laparoscopic hemi-hepatectomies performed between 2015 and 2022 met study inclusion criteria. Of these, 11 were L-DH. PSM in a 1:2 ratio of L-DH versus L-NDH and 1:1 ratio of L-DH versus O-DH were performed, identifying patients with similar baseline clinicopathological characteristics. RESULTS: After 2:1 matching, the L-DH cohort were significantly younger (P < 0.001) and had lower ASA scores (P < 0.001) than the L-NDH cohort. L-DH was associated with a longer median operating time (P < 0.001) and shorter median postoperative stay (P < 0.001) than L-NDH. After 1:1 matching, there were no significant differences in baseline demographic between the L-DH and O-DH cohorts. L-DH was associated with lower median blood loss (P = 0.040) and shorter length of stay compared to O-DH (P = 0.004). There were no significant differences in recipient outcomes for both cohorts. CONCLUSION: L-DH can be adopted safely by surgeons experienced in L-NDH and ODH. It is associated with decreased blood loss and shorter length of stay compared to O-DH.

Preoperative Predictors of Early Recurrence After Liver Resection for Multifocal Hepatocellular Carcinoma.

BACKGROUND: Liver transplantation remains the optimal treatment for multifocal hepatocellular carcinoma (HCC). However, due to resource constrains, other therapeutic modalities such as liver resection (LR), are frequently utilized. LR, however, has to be balanced against potential morbidity and mortality along with the risks of early recurrence leading to futile surgery. In this study, we evaluated preoperative factors, including inflammatory indices, in predicting early (< 1 year) recurrence in patients who underwent LR for multifocal HCC. METHODS: This was a post hoc analysis of 250 consecutive patients with multifocal HCC who underwent LR. RESULTS: After exclusion of 10 patients with 30-day/in-hospital mortality, 240 were included of which 134 (55.8%) developed early recurrence. Hepatitis B/C aetiology, 3/ > more hepatic nodules and elevated alpha-fetoprotein (AFP) ≥ 200 ng/ml were significant independent preoperative predictors of early recurrence. The early recurrence rate was 72.1% when 2 out of 3 significant predictive factors were present. The conglomerate of all 3 factors predicted early recurrence of 100% with a statistically significant association between number of predictive factors and early recurrence (p < 0.001). CONCLUSION: Better patient selection via the use of preoperative predictive factors of early recurrence such as hepatitis B/C aetiology, ≥ 3 nodules and elevated AFP ≥ 200 ng/ml may assist in identifying patients in whom LR is deemed futile and improve resource allocation.

Multi-region sampling with paired sample sequencing analyses reveals sub-groups of patients with novel patient-specific dysregulation in Hepatocellular Carcinoma.

BACKGROUND: Conventional differential expression (DE) testing compares the grouped mean value of tumour samples to the grouped mean value of the normal samples, and may miss out dysregulated genes in small subgroup of patients. This is especially so for highly heterogeneous cancer like Hepatocellular Carcinoma (HCC). METHODS: Using multi-region sampled RNA-seq data of 90 patients, we performed patient-specific differential expression testing, together with the patients' matched adjacent normal samples. RESULTS: Comparing the results from conventional DE analysis and patient-specific DE analyses, we show that the conventional DE analysis omits some genes due to high inter-individual variability present in both tumour and normal tissues. Dysregulated genes shared in small subgroup of patients were useful in stratifying patients, and presented differential prognosis. We also showed that the target genes of some of the current targeted agents used in HCC exhibited highly individualistic dysregulation pattern, which may explain the poor response rate. DISCUSSION/CONCLUSION: Our results highlight the importance of identifying patient-specific DE genes, with its potential to provide clinically valuable insights into patient subgroups for applications in precision medicine.

Defining Global Benchmarks for Laparoscopic Liver Resections: An International Multicenter Study.

OBJECTIVE: To establish global benchmark outcomes indicators after laparoscopic liver resections (L-LR). BACKGROUND: There is limited published data to date on the best achievable outcomes after L-LR. METHODS: This is a post hoc analysis of a multicenter database of 11,983 patients undergoing L-LR in 45 international centers in 4 continents between 2015 and 2020. Three specific procedures: left lateral sectionectomy (LLS), left hepatectomy (LH), and right hepatectomy (RH) were selected to represent the 3 difficulty levels of L-LR. Fifteen outcome indicators were selected to establish benchmark cutoffs. RESULTS: There were 3519 L-LR (LLS, LH, RH) of which 1258 L-LR (40.6%) cases performed in 34 benchmark expert centers qualified as low-risk benchmark cases. These included 659 LLS (52.4%), 306 LH (24.3%), and 293 RH (23.3%). The benchmark outcomes established for operation time, open conversion rate, blood loss ≥500 mL, blood transfusion rate, postoperative morbidity, major morbidity, and 90-day mortality after LLS, LH, and RH were 209.5, 302, and 426 minutes; 2.1%, 13.4%, and 13.0%; 3.2%, 20%, and 47.1%; 0%, 7.1%, and 10.5%; 11.1%, 20%, and 50%; 0%, 7.1%, and 20%; and 0%, 0%, and 0%, respectively. CONCLUSIONS: This study established the first global benchmark outcomes for L-LR in a large-scale international patient cohort. It provides an up-to-date reference regarding the "best achievable" results for L-LR for which centers adopting L-LR can use as a comparison to enable an objective assessment of performance gaps and learning curves.

Association of standardized liver volume and body mass index with outcomes of minimally invasive liver resections.

INTRODUCTION: While minimally invasive liver resections (MILR) have demonstrated advantages in improved post-operative recovery, widespread adoption is hampered by inherent technical difficulties. Our study attempts to analyze the role of anthropometric measures in MILR-related outcomes. METHODS: Between 2012 and 2020, 676 consecutive patients underwent MILR at the Singapore General Hospital of which 565 met study criteria and were included. Patients were stratified based on Body Mass Index (BMI) as well as Standardized Liver Volumes (SLV). Associations between BMI and SLV to selected peri-operative outcomes were analyzed using restricted cubic splines. RESULTS: A BMI of ≥ 29 was associated with increase in blood loss [Mean difference (MD) 69 mls, 95% CI 2 to 137] as well as operative conversions [Relative Risk (RR) 1.63, 95% CI 1.02 to 2.62] among patients undergoing MILR while a SLV of 1600 cc or higher was associated with an increase in blood loss (MD 30 mls, 95% CI 10 to 49). In addition, a BMI of ≤ 20 was associated with an increased risk of major complications (RR 2.25, 95% 1.16 to 4.35). The magnitude of differences observed in these findings increased with each unit change in BMI and SLV. CONCLUSION: Both BMI and SLV were useful anthropometric measures in predicting peri-operative outcomes in MILR and may be considered for incorporation in future difficulty scoring systems for MILR.

IFNγ-IL-17+ CD8 T cells contribute to immunosuppression and tumor progression in human hepatocellular carcinoma.

IL-17-producing CD8 (Tc17) T cells have been shown to play an important role in infection and chronic inflammation, however their implications in hepatocellular carcinoma (HCC) remain elusive. In this study, we performed cytometry by time-of-flight (CyTOF) and revealed the distinctive immunological phenotypes of two IFNγ+ and IFNγ- Tc17 subsets that were preferentially enriched in human HCC. Single-cell RNA-sequencing analysis further revealed regulatory circuits governing the different phenotypes of these Tc17 subsets. In particular, we discovered that IFNγ- Tc17 subset demonstrated pro-tumoral characteristics and expressed higher levels of CCL20. This corresponded to increased tumor infiltration of T regulatory cells (Treg) validated by immunohistochemistry in another independent HCC cohort, demonstrating the immunosuppressive functions of IFNγ- Tc17 subset. Most importantly, higher intra-tumoral proportions of IFNγ- Tc17 were associated with poorer prognosis in patients with HCC and this was further validated in The Cancer Genome Atlas (TCGA) HCC cohort. Taken together, this compendium of transcriptomic and proteomic data of Tc17 subsets sheds light on the immunosuppressive phenotypes of IFNγ- Tc17 and its implications in HCC progression.

Intraoperative blood transfusion does not impact overall and recurrence-free survival after curative hepatectomy for hepatocellular carcinoma: A propensity-score-matched and inverse probability of treatment-weighted study.

INTRODUCTION: Our primary objective was to determine if receiving intraoperative blood transfusion was a significant prognostic factor for overall and recurrence-free survival after curative resection of hepatic cellular carcinoma (HCC). METHODOLOGY: Between 2001 and 2018, 1092 patients with histologically proven primary HCC who underwent curative liver resection were retrospectively reviewed. Primary study endpoints were recurrence-free survival (RFS) and overall survival (OS). The main analysis was undertaken using propensity-score matching (PSM) to minimize confounding and selection biases in the comparison of patients with or without transfusion. RESULTS: There were 220 patients who received and 666 patients who did not receive intraoperative blood transfusion. The PSM cohort consisted of 163 pairs of patients. After PSM, the only perioperative outcome that appeared to significantly affect whether patients would receive blood transfusion was median blood loss (p = 0.001). In the PSM cohort, whether patients received blood transfusion was neither associated with OS (p = 0.759) nor RFS (p = 0.830). When the volume of blood transfusion was analyzed as a continuous variable, no significant dose-response relationship between blood transfusion volume and HR for OS and RFS was noted. CONCLUSION: Intraoperative blood transfusion had no significant impact on the survival outcomes in patients who receive curative resection in primary HCC.

Limited liver resections in the posterosuperior segments: international multicentre propensity score-matched and coarsened exact-matched analysis comparing the laparoscopic and robotic approaches.

BACKGROUND: Limited liver resections (LLRs) for tumours located in the posterosuperior segments of the liver are technically demanding procedures. This study compared outcomes of robotic (R) and laparoscopic (L) LLR for tumours located in the posterosuperior liver segments (IV, VII, and VIII). METHODS: This was an international multicentre retrospective analysis of patients who underwent R-LLR or L-LLR at 24 centres between 2010 and 2019. Patient demographics, perioperative parameters, and postoperative outcomes were analysed; 1 : 3 propensity score matching (PSM) and 1 : 1 coarsened exact matching (CEM) were performed. RESULTS: Of 1566 patients undergoing R-LLR and L-LLR, 983 met the study inclusion criteria. Before matching, 159 R-LLRs and 824 L-LLRs were included. After 1 : 3 PSM of 127 R-LLRs and 381 L-LLRs, comparison of perioperative outcomes showed that median blood loss (100 (i.q.r. 40-200) versus 200 (100-500) ml; P = 0.003), blood loss of at least 500 ml (9 (7.4 per cent) versus 94 (27.6 per cent); P < 0.001), intraoperative blood transfusion rate (4 (3.1 per cent) versus 38 (10.0 per cent); P = 0.025), rate of conversion to open surgery (1 (0.8 per cent) versus 30 (7.9 per cent); P = 0.022), median duration of Pringle manoeuvre when applied (30 (20-46) versus 40 (25-58) min; P = 0.012), and median duration of operation (175 (130-255) versus 224 (155-300); P < 0.001) were lower in the R-LLR group compared with the L-LLR group. After 1 : 1 CEM of 104 R-LLRs with 104 L-LLRs, R-LLR was similarly associated with significantly reduced blood loss and a lower rate of conversion to open surgery. CONCLUSION: Based on a matched analysis of well selected patients, both robotic and laparoscopic access could be undertaken safely with good outcomes for tumours in the posterosuperior liver segments.

Poor utility of current nomograms assessing the risk of intraoperative blood transfusion in patients undergoing liver resection for hepatocellular carcinoma and proposal of a new model.

BACKGROUND: The Memorial Sloan Kettering Cancer Center nomogram, the predictive scoring system of Yamamoto et al, and the 3-point transfusion risk score of Lemke et al are models used to determine the probability of receiving intraoperative blood transfusion in patients undergoing liver resection. However, the external validity of these models remains unknown. The objective of this study was to evaluate their predictive performance in an external cohort of patients with hepatocellular carcinoma. We also aimed to identify predictors of blood transfusion and develop a new predictive model for blood transfusion. METHODS: Post hoc analysis of our prospective database of 1,081 patients undergoing liver resection for hepatocellular carcinoma from 2001 to 2018. The predictive performance of current prediction models was evaluated using C statistics. Demographic and clinical variables as predictors of blood transfusion were assessed. Using logistic regression, an alternative model was created. RESULTS: The Lemke transfusion risk score performed better than the Memorial Sloan Kettering Cancer Center nomogram (0.69, 95% confidence interval 0.66-0.73 vs 0.66, 95% liver resection 0.62-0.69) (P < .001). The model from Yamamoto et al performed comparably with no statistically significant differences found through pairwise comparison. In our alternative model, hemoglobin level, albumin level, liver resection type, and tumor size were independent predictors of blood transfusion. The new HATS model obtained a C statistic of 0.74 (95% confidence interval 0.71-0.78), performing significantly better than the previous 3 models (P ≤ 0.001 for all). CONCLUSION: The existing Memorial Sloan Kettering Cancer Center, Yamamoto et al, and Lemke et al had nomograms with the suboptimal accuracy of predicting risk of intraoperative blood transfusion in patients undergoing liver resection for hepatocellular carcinoma. The proposed HATS model was more accurate at predicting patients at risk of blood transfusion.

Extending Surgical Resection for Hepatocellular Carcinoma Beyond Barcelona Clinic for Liver Cancer (BCLC) Stage A: A Novel Application of the Modified BCLC Staging System.

Objective: We aimed to prognosticate survival after surgical resection of HCC stratified by stage with amalgamation of the modified Barcelona Clinic Liver Cancer (BCLC) staging system and location of tumour. Methods: This single-institutional retrospective cohort study included patients with HCC who underwent surgical resection between 1st January 2000 to 30th June 2016. Participants were divided into 6 different subgroups: A-u) Within MC with Unilobar lesions; A-b) Within MC + Bilobar lesions; B1-u) Out of MC + within Up-To-7 + Unilobar lesions; B1-b) Out of MC + within Up-to-7 + Bilobar lesions; B2-u) Out of MC + Out of Up-To-7 + Unilobar lesions; B2-b) Out of MC + Out of Up-To-7 + Bilobar lesions. A separate survival analysis was conducted for solitary HCC lesions according to three subgroups: A-S (Within MC); B1-S (Out of MC + within Up-To-7); B2-S (Out of MC + out of Up-To-7). Results: A total of 794 of 1043 patients with surgical resection for HCC were analysed. Groups A-u (64.6%), A-b (58.4%) and B1-u (56.2%) had 5-year cumulative overall survival (OS) rates above 50% after surgical resection and median OS exceeding 60 months (P = 0.0001). The 5-year cumulative recurrence-free survival rates (RFS) were 40.4% (group A-u), 38.2% (group A-b), 36.3% (group B1-u), 24.6% (group B2-u), and 7.3% (group B2-b)(P=0.0001). For solitary lesions, the 5-year OS for the subgroups were A-S (65.1%), B1-S (56.0%) and B2-S (47.1%) (P = 0.0003). Compared to A-S, there was also a significant trend towards relatively poorer OS as the lesion sizes increased in B1-S (HR 1.46, 95% CI 1.03-2.08) and B2-S (HR 1.65, 95% CI 1.25-2.18). Conclusion: We adopted a novel approach combining the modified BCLC B sub-classification and dispersion of tumour to show that surgical resection in intermediate stage HCC can be robustly prognosticated. We found that size prognosticates resection outcomes in solitary tumours.

A systematic review and network meta-analysis of outcomes after open, mini-laparotomy, hybrid, totally laparoscopic, and robotic living donor right hepatectomy.

BACKGROUND: A systematic review and network meta-analysis was performed to compare outcomes after living donor right hepatectomy via the following techniques: conventional open (Open), mini-laparotomy (Minilap), hybrid (Hybrid), totally laparoscopic (Lap), and robotic living donor right hepatectomy (Robotic). METHODS: PubMed, EMBASE, Cochrane, and Scopus were searched from inception to August 2021 for comparative studies of patients who underwent living donor right hepatectomy. RESULTS: Nineteen studies comprising 2,261 patients were included. Operation time was longer in Lap versus Minilap and Open (mean difference 65.09 min, 95% confidence interval 3.40-126.78 and mean difference 34.81 minutes, 95% confidence interval 1.84-67.78), and in Robotic versus Hybrid, Lap, Minilap, and Open (mean difference 144.72 minutes, 95% confidence interval 89.84-199.59, mean difference 113.24 minutes, 95% confidence interval 53.28-173.20, mean difference 178.33 minutes, 95% confidence interval 105.58-251.08 and mean difference 148.05 minutes, 95% confidence interval 97.35-198.74, respectively). Minilap and Open were associated with higher blood loss compared to Lap (mean difference 258.67 mL, 95% confidence interval 107.00-410.33 and mean difference 314.11 mL, 95% confidence interval 143.84-484.37) and Robotic (mean difference 205.60 mL, 95% confidence interval 45.92-365.28 and mean difference 261.04 mL, 95% confidence interval 84.26-437.82). Open was associated with more overall complications compared to Minilap (odds ratio 2.60, 95% confidence interval 1.11-6.08). Recipient biliary complication rate was higher in Minilap and Open versus Hybrid (odds ratio 3.91, 95% confidence interval 1.13-13.55 and odds ratio 11.42, 95% confidence interval 2.27-57.49), and lower in Open versus Minilap (OR 0.07, 95% confidence interval 0.01-0.34). CONCLUSION: Minimally invasive donor right hepatectomy via the various techniques is safe and feasible when performed in high-volume centers, with no major differences in donor complication rates and comparable recipient outcomes once surgeons have mounted the learning curve.

Laparoscopic versus open caudate lobe liver resections: a 1:2 propensity score-matched controlled study based on a single institution experience.

BACKGROUND: Despite the wide use of laparoscopy for liver resection, laparoscopic caudate lobe resections(L-CLR) remain technically challenging, only attempted by experts in the field. The primary objective of this study was to determine the safety and compare the perioperative outcomes of L-CLR with O-CLR based on our single institution experience in a 1:2 propensity score-matched controlled study based on our single institution experience. METHODS: Between 2004 and 2020, 67 consecutive patients who underwent CLR at Singapore General Hospital were identified. Propensity score matching (PSM) of laparoscopic versus open caudate lobe resections(O-CLR) was performed in a 1:2 ratio with no replacements using nearest neighbour matching method. RESULTS: L-CLR was associated with a significantly decreased median blood loss (150 mL versus 500 mL, P = 0.001) and a decreased median post-operative stay (3 days versus 7.5 days, P = <0.01) in the unmatched cohorts. After 1:2 propensity score matching, these results were again demonstrated with a significantly lower blood loss (150 mL versus 400 mL, P = 0.016) and a shorter postoperative stay (3 days versus 7 days, P = <0.01) in favour of L-CLR. 30-day readmission and major morbidity (Clavien-Dindo grade > 2) rates were all in favour of L-CLR as well but could not reach statistical significance. CONCLUSION: L-CLR can be safely performed by experienced surgeons. It is associated with decreased blood loss and shorter perioperative stay compared to O-CLR.

Dynamic phenotypic heterogeneity and the evolution of multiple RNA subtypes in hepatocellular carcinoma: the PLANET study.

Intra-tumor heterogeneity (ITH) is a key challenge in cancer treatment, but previous studies have focused mainly on the genomic alterations without exploring phenotypic (transcriptomic and immune) heterogeneity. Using one of the largest prospective surgical cohorts for hepatocellular carcinoma (HCC) with multi-region sampling, we sequenced whole genomes and paired transcriptomes from 67 HCC patients (331 samples). We found that while genomic ITH was rather constant across stages, phenotypic ITH had a very different trajectory and quickly diversified in stage II patients. Most strikingly, 30% of patients were found to contain more than one transcriptomic subtype within a single tumor. Such phenotypic ITH was found to be much more informative in predicting patient survival than genomic ITH and explains the poor efficacy of single-target systemic therapies in HCC. Taken together, we not only revealed an unprecedentedly dynamic landscape of phenotypic heterogeneity in HCC, but also highlighted the importance of studying phenotypic evolution across cancer types.

Propensity Score-Matched Analysis Comparing Robotic and Laparoscopic Right and Extended Right Hepatectomy.

Importance: Laparoscopic and robotic techniques have both been well adopted as safe options in selected patients undergoing hepatectomy. However, it is unknown whether either approach is superior, especially for major hepatectomy such as right hepatectomy or extended right hepatectomy (RH/ERH). Objective: To compare the outcomes of robotic vs laparoscopic RH/ERH. Design, Setting, and Participants: In this case-control study, propensity score matching analysis was performed to minimize selection bias. Patients undergoing robotic or laparoscopic RH/EHR at 29 international centers from 2008 to 2020 were included. Interventions: Robotic vs laparoscopic RH/ERH. Main Outcomes and Measures: Data on patient demographics, tumor characteristics, and short-term perioperative outcomes were collected and analyzed. Results: Of 989 individuals who met study criteria, 220 underwent robotic and 769 underwent laparoscopic surgery. The median (IQR) age in the robotic RH/ERH group was 61.00 (51.86-69.00) years and in the laparoscopic RH/ERH group was 62.00 (52.03-70.00) years. Propensity score matching resulted in 220 matched pairs for further analysis. Patients' demographics and tumor characteristics were comparable in the matched cohorts. Robotic RH/ERH was associated with a lower open conversion rate (19 of 220 [8.6%] vs 39 of 220 [17.1%]; P = .01) and a shorter postoperative hospital stay (median [IQR], 7.0 [5.0-10.0] days; mean [SD], 9.11 [7.52] days vs median [IQR], 7.0 [5.75-10.0] days; mean [SD], 9.94 [8.99] days; P = .048). On subset analysis of cases performed between 2015 and 2020 after a center's learning curve (50 cases), robotic RH/ERH was associated with a shorter postoperative hospital stay (median [IQR], 6.0 [5.0-9.0] days vs 7.0 [6.0-9.75] days; P = .04) with a similar conversion rate (12 of 220 [7.6%] vs 17 of 220 [10.8%]; P = .46). Conclusion and Relevance: Robotic RH/ERH was associated with a lower open conversion rate and shorter postoperative hospital stay compared with laparoscopic RH/ERH. The difference in open conversion rate was associated with a significant decrease for laparoscopic but not robotic RH/ERH after a center had mounted the learning curve. Use of robotic platform may help to overcome the initial challenges of minimally invasive RH/ERH.

Trajectory of immune evasion and cancer progression in hepatocellular carcinoma.

Immune evasion is key to cancer initiation and later at metastasis, but its dynamics at intermediate stages, where potential therapeutic interventions could be applied, is undefined. Here we show, using multi-dimensional analyses of resected tumours, their adjacent non-tumour tissues and peripheral blood, that extensive immune remodelling takes place in patients with stage I to III hepatocellular carcinoma (HCC). We demonstrate the depletion of anti-tumoural immune subsets and accumulation of immunosuppressive or exhausted subsets along with reduced tumour infiltration of CD8 T cells peaking at stage II tumours. Corresponding transcriptomic modification occur in the genes related to antigen presentation, immune responses, and chemotaxis. The progressive immune evasion is validated in a murine model of HCC. Our results show evidence of ongoing tumour-immune co-evolution during HCC progression and offer insights into potential interventions to reverse, prevent or limit the progression of the disease.

Hypoxia-driven immunosuppression by Treg and type-2 conventional dendritic cells in HCC.

BACKGROUND AND AIMS: Hypoxia is one of the central players in shaping the immune context of the tumor microenvironment (TME). However, the complex interplay between immune cell infiltrates within the hypoxic TME of HCC remains to be elucidated. APPROACH AND RESULTS: We analyzed the immune landscapes of hypoxia-low and hypoxia-high tumor regions using cytometry by time of light, immunohistochemistry, and transcriptomic analyses. The mechanisms of immunosuppression in immune subsets of interest were further explored using in vitro hypoxia assays. Regulatory T cells (Tregs) and a number of immunosuppressive myeloid subsets, including M2 macrophages and human leukocyte antigen-DR isotype (HLA-DRlo ) type 2 conventional dendritic cell (cDC2), were found to be significantly enriched in hypoxia-high tumor regions. On the other hand, the abundance of active granzyme Bhi PD-1lo CD8+ T cells in hypoxia-low tumor regions implied a relatively active immune landscape compared with hypoxia-high regions. The up-regulation of cancer-associated genes in the tumor tissues and immunosuppressive genes in the tumor-infiltrating leukocytes supported a highly pro-tumorigenic network in hypoxic HCC. Chemokine genes such as CCL20 (C-C motif chemokine ligand 20) and CXCL5 (C-X-C motif chemokine ligand 5) were associated with recruitment of both Tregs and HLA-DRlo cDC2 to hypoxia-high microenvironments. The interaction between Tregs and cDC2 under a hypoxic TME resulted in a loss of antigen-presenting HLA-DR on cDC2. CONCLUSIONS: We uncovered the unique immunosuppressive landscapes and identified key immune subsets enriched in hypoxic HCC. In particular, we identified a potential Treg-mediated immunosuppression through interaction with a cDC2 subset in HCC that could be exploited for immunotherapies.

Effect of age on the short- and long-term outcomes of patients undergoing curative liver resection for HCC.

BACKGROUND: Few studies have evaluated the outcomes of curative liver resection (LR) in octogenarian patients, analysed cancer-specific survival (CSS) with HCC-related death or explored the age-varying effect of HCC-related death in elderly patients undergoing LR. We aim to determine the effect of age on the short and long-term outcomes of LR for HCC. METHODOLOGY: Between 2000 and 2018, 1,092 patients with primary HCC who underwent LR with curative intent were retrospectively reviewed. The log-rank test and Gray's test were used to assess the equality of survivor functions and competing risk-adjusted cumulative incidence functions between patients in the three age categories respectively. Regression adjustment was used to control for confounding bias via a Principal Component Analysis. Quantile, Firth logistic, Cox, and Fine-Gray competing risk regression were used to analyse continuous, binary, time-to-event, and cause-specific survival respectively. Restricted cubic splines were used to illustrate the dose-effect relationship between age and patient outcomes. RESULTS: The study comprised of 764 young patients (<70 years), 278 septuagenarians (70-79 years old) and 50 octogenarians (≥80 years). Compared to young patients, octogenarians had significantly lower 5-year OS(62.1% vs 37.7%, p < 0.001). However, there was no significant difference in 1-year RFS(73.1% vs 67.0%, p = 0.774) or 5-year CSS (5.4% vs 15.2%, p = 0.674). Every 10-year increase in age was significantly associated with an increase length of stay (p < 0.001), postoperative complications (p = 0.004) and poorer OS(p = 0.018) but not significantly associated with major complications (p = 0.279), CSS(p = 0.338) or RFS(p = 0.941). CONCLUSION: Age by itself was associated with OS after LR for HCC but was not a significant risk factor for HCC-related death.

Minimally Invasive vs Open Major Hepatectomies for Liver Malignancies: a Propensity Score-Matched Analysis.

BACKGROUND: The majority of evidence with regards to minimally invasive liver resection (MILR) favors its application in minor hepatectomies. We conducted a propensity score-matched (PSM) analysis to determine its feasibility and safety in major hepatectomies (MIMH) for liver malignancies. METHODS: Retrospective review of 130 patients who underwent MIMH and 490 patients who underwent open major hepatectomy (OMH) for malignant pathologies was performed. PSM in a 1:1 ratio identified two groups of patients with similar baseline clinicopathological characteristics. Perioperative outcomes were then compared. Major hepatectomies included traditional major (>3 segments) and technical major hepatectomies (right anterior and right posterior sectionectomies). RESULTS: Both cohorts were well-matched for baseline characteristics after PSM. Of 130 MIMH cases, there were 12 conversions to open. Comparison of perioperative outcomes demonstrated a significant association of MIMH with longer operation time and more frequent application of Pringle's maneuver (PM), but decreased postoperative stay. These results were consistent on a subgroup analysis that only included patients undergoing traditional major hepatectomies. A second subgroup analysis restricted to cirrhotic patients demonstrated that while perioperative outcomes were equivalent, MIMH was similarly associated with a longer operative time. Subset analyses of resections performed after 2015 demonstrated that MIMH was additionally associated with a lower postoperative morbidity compared to OMH. CONCLUSION: Comparison of perioperative and short-term oncological outcomes between MIMH and OMH for malignancies demonstrated that MIMH is feasible and safe. It is associated with a shorter hospital stay at the expense of a longer operation time compared to OMH.

Impact of introduction of an enhanced recovery protocol on the outcomes of laparoscopic liver resections: A propensity-score matched study.

BACKGROUND: Presently, data on the impact of enhanced recovery protocols on the outcomes of laparoscopic liver resection remain limited. We performed propensity matched analysis comparing the outcomes between patients undergoing laparoscopic liver resection before and after the introduction of an enhanced recovery protocol. METHODS: Between 2013 and 2019, 462 consecutive patients underwent laparoscopic liver resection by 3 surgeons of which 360 met the study inclusion criteria. There were 89 patients who underwent surgery under an enhanced recovery protocol and 271 without an enhanced recovery protocol. One-to-one propensity matched analysis was performed for 84 enhanced recovery protocol patients and 84 nonenhanced recovery protocol patients. RESULTS: Comparisons between propensity matched cohorts revealed that patients who received laparoscopic liver resection with enhanced recovery protocol had reduced median blood loss (200 vs 300 mL, P = .013), postoperative stay (3 vs 4 days, P = .003), and lower open conversion rates (0% vs 8.3%, P = .008). There was no difference in other key perioperative outcomes such as operation time, postoperative morbidity, postoperative major morbidity, and 30-day readmission rates. CONCLUSION: A combined approach of enhanced recovery protocol and laparoscopic liver resection was associated with improved perioperative outcomes as opposed to laparoscopic liver resection alone.