Stereotactic Body Radiotherapy and Liver Transplant for Liver Cancer: A Nonrandomized Controlled Trial.

Importance: Whether stereotactic body radiotherapy (SBRT) as a bridge to liver transplant for hepatocellular carcinoma (HCC) is effective and safe is still unknown. Objective: To investigate the feasibility of SBRT before deceased donor liver transplant (DDLT) for previously untreated unresectable HCC. Design, Setting, and Participants: In this phase 2 nonrandomized controlled trial conducted between June 1, 2015, and October 18, 2019, 32 eligible patients within UCSF (University of California, San Francisco) criteria underwent dual-tracer (18F-fluorodeoxyglucose and 11C-acetate [ACC]) positron emission tomography with computed tomography (PET-CT) and magnetic resonance imaging (MRI) with gadoxetate followed by SBRT of 35 to 50 Gy in 5 fractions, and the same imaging afterward while awaiting DDLT. Statistical analysis was performed on an intention-to-treat basis between October 1 and 31, 2023. Intervention: Patients received SBRT followed by DDLT when matched deceased donor grafts were available. Main Outcomes and Measures: Coprimary end points were progression-free survival (PFS) and objective response rates (ORRs) by the Response Evaluation Criteria in Solid Tumors, version 1.1 (RECIST 1.1), modified RECIST (mRECIST), and PET Response Criteria in Solid Tumors (PERCIST). Secondary end points were local control rate, overall survival (OS), and safety. Results: A total of 32 patients (median age, 59 years [IQR, 54-63 years]; 22 men [68.8%]) with 56 lesions received SBRT. After a median follow-up of 74.6 months (IQR, 40.1-102.9 months), the median PFS was 17.6 months (95% CI, 6.6-28.6 months), and the median OS was 60.5 months (95% CI, 29.7-91.2 months). The 5-year PFS was 39.9% (95% CI, 19.9%-59.9%), and the 5-year OS was 51.3% (95% CI, 31.7%-70.9%). In terms of number of patients, ORRs were 62.5% ([n = 20] 95% CI, 54.2%-68.7%) by RECIST 1.1, 71.9% ([n = 23] 95% CI, 63.7%-79.0%) by mRECIST, and 78.1% ([n = 25] 95% CI, 73.2%-86.7%) by PERCIST. In terms of number of lesions, ORRs were 75.0% ([n = 42] 95% CI, 61.6%-80.8%) by RECIST 1.1, 83.9% ([n = 47] 95% CI, 74.7%-90.6%) by mRECIST, and 87.5% ([n = 49] 95% CI, 81.3%-98.6%) by PERCIST. Twenty patients with 36 lesions received DDLT, of whom 15 patients (75.0%) with 21 lesions (58.3%) exhibited pathologic complete response. Multivariable analyses revealed that pretreatment metabolic tumor volume (MTV) based on ACC (hazard ratio [HR], 1.06 [95% CI, 1.01-1.10]; P = .01) and complete metabolic response (CMR) by PERCIST (HR, 0.31 [95% CI, 0.10-0.96]; P = .04) were associated with PFS, while pretreatment MTV based on ACC (HR, 1.07 [95% CI, 1.03-1.16]; P = .01), total lesion activity based on ACC (HR, 1.01 [95% CI, 1.00-1.02]; P = .02), and CMR by PERCIST (HR, 0.21 [95% CI, 0.07-0.73]; P = .01) were associated with OS. Toxic effects associated with SBRT were reported for 9 patients (28.1%), with 1 grade 3 event. Conclusions and Relevance: This phase 2 nonrandomized controlled trial demonstrated promising survival and safety outcomes of SBRT before DDLT for unresectable HCC. Future randomized clinical trials are warranted.

Correlation of pathological examination with indocyanine green (ICG) intensity gradients: a prospective study in patients with liver tumor.

BACKGROUND: Intraoperative indocyanine green (ICG) fluorescence imaging has been shown to be a new and innovative way to illustrate the optimal resection margin in hepatectomy for hepatocellular carcinoma. This study investigated its accuracy in resection margin determination by looking into the correlation of ICG intensity gradients with pathological examination results of resected specimens. METHODS: This was a prospective, single-center, non-randomized controlled study. Patients who had liver tumors indicating liver resection were recruited. The hypothesis was that the use of intraoperative near-infrared/ICG fluorescence imaging would be a promising guiding tool for removing hepatocellular carcinoma with a better resection margin. Patients were given ICG (0.25 mg/kg) 1 day before operation. Resected specimens were inspected under a fluorescent imaging system. Biopsies were taken from tumors and normal tissue. Color signals obtained from ICG fluorescence imaging were compared with biopsies for analysis. RESULTS: Twenty-two patients were recruited for study. The median size of their tumors was 2.25 cm. One patient had resection margin involvement. Under ICG fluorescence, the tumors typically lighted up as yellow color, wrapped by a zone of green color. Tumors of 17 patients (77.3%) displayed yellow color and were confirmed malignancy, while tumors of 12 patients (54.5%) displayed green color and were confirmed malignancy. Receiver operating characteristic curve was used to measure the sensitivity and specificity of the green color to look for a clear resection margin. The area under the curve was 85.3% (p = 0.019, 95% confidence interval 0.696-1.000), with a sensitivity of 0.706 and specificity of 1.000. CONCLUSION: The use of ICG fluorescence can be helpful in determining resection margins. Resection of tumor should include complete resection of the green zone shown in the fluorescence image.

Stage-by-stage analysis of the effect of blood transfusion on survival after curative hepatectomy for hepatocellular carcinoma-a retrospective study.

OBJECTIVE: This study is to examine the impact of perioperative (intraoperative/postoperative) blood transfusion on the outcomes of curative hepatectomy for hepatocellular carcinoma. Hepatectomy is a well-established curative treatment for hepatocellular carcinoma, and blood transfusion cannot always be avoided in treating the disease. METHODS: A retrospective study of patients having curative hepatectomy for hepatocellular carcinoma from January 2010 to December 2019 at a single center was conducted. The patients were stratified by their disease stage. Patients with and without perioperative blood transfusion were matched by propensity-score matching and compared for each disease stage. Univariate and multivariate analyses were performed to identify prognostic factors for overall survival for each stage. RESULTS: A total of 846 patients were studied. Among them, 125 received perioperative blood transfusion and 720 did not. Patients with blood transfusion had worse disease-free and overall survival. After stratification and matching, the ratios of transfusion to non-transfusion were 33:165 (stage 1), 28:140 (stage 2), and 45:90 (stage 3). Perioperative blood transfusion was associated with a higher incidence of postoperative complications in all three disease stages (p = 0.004/0.006/0.017), and hence longer hospitalization (p < 0.001 in all stages), but had no significant impact on hospital mortality (p = 0.119/0.118/0.723), 90-day mortality (p = 0.259/0.118/0.723), disease-free survival (p = 0.128/0.826/0.511), or overall survival (p = 0.869/0.122/0.122) in any disease stage. Prognostic factors for overall survival included tumor size, tumor number, alpha-fetoprotein level, and postoperative complication of grade ≥ 3A. CONCLUSION: Perioperative blood transfusion was associated with a higher incidence of complications but had no significant impact on survival after curative hepatectomy for hepatocellular carcinoma.

Biliary complications after adult-to-adult living-donor liver transplantation: An international multicenter study of 3633 cases.

In living-donor liver transplantation, biliary complications including bile leaks and biliary anastomotic strictures remain significant challenges, with incidences varying across different centers. This multicentric retrospective study (2016-2020) included 3633 adult patients from 18 centers and aimed to identify risk factors for these biliary complications and their impact on patient survival. Incidences of bile leaks and biliary strictures were 11.4% and 20.6%, respectively. Key risk factors for bile leaks included multiple bile duct anastomoses (odds ratio, [OR] 1.8), Roux-en-Y hepaticojejunostomy (OR, 1.4), and a history of major abdominal surgery (OR, 1.4). For biliary anastomotic strictures, risk factors were ABO incompatibility (OR, 1.4), blood loss >1 L (OR, 1.4), and previous abdominal surgery (OR, 1.7). Patients experiencing biliary complications had extended hospital stays, increased incidence of major complications, and higher comprehensive complication index scores. The impact on graft survival became evident after accounting for immortal time bias using time-dependent covariate survival analysis. Bile leaks and biliary anastomotic strictures were associated with adjusted hazard ratios of 1.7 and 1.8 for graft survival, respectively. The study underscores the importance of minimizing these risks through careful donor selection and preoperative planning, as biliary complications significantly affect graft survival, despite the availability of effective treatments.

Indications of pro-inflammatory cytokines in laparoscopic and open liver resection for early-stage hepatocellular carcinoma.

BACKGROUND: Our clinical practice of laparoscopic liver resection (LLR) had achieved better short-term and long-term benefits for patients with hepatocellular carcinoma (HCC) over open liver resection (OLR), but the underlying mechanisms are not clear. This study was to find out whether systemic inflammation plays an important role. METHODS: A total of 103 patients with early-stage HCC under liver resection were enrolled (LLR group, n = 53; OLR group, n = 50). The expression of 9 inflammatory cytokines in patients at preoperation, postoperative day 1 (POD1) and POD7 was quantified by Luminex Multiplex assay. The relationships of the cytokines and the postoperative outcomes were compared between LLR and OLR. RESULTS: Seven of the circulating cytokines were found to be significantly upregulated on POD1 after LLR or OLR compared to their preoperative levels. Compared to OLR, the POD1 levels of granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin-6 (IL-6), IL-8, and monocyte chemoattractant protein-1 (MCP-1) in the LLR group were significantly lower. Higher POD1 levels of these cytokines were significantly correlated with longer operative time and higher volume of blood loss during operation. The levels of these cytokines were positively associated with postoperative liver injury, and the length of hospital stay. Importantly, a high level of IL-6 at POD1 was a risk factor for HCC recurrence and poor disease-free survival after liver resection. CONCLUSIONS: Significantly lower level of GM-CSF, IL-6, IL-8, and MCP-1 after liver resection represented a milder systemic inflammation which might be an important mechanism to offer better short-term and long-term outcomes in LLR over OLR.

Arachidonic acid activates NLRP3 inflammasome in MDSCs via FATP2 to promote post-transplant tumour recurrence in steatotic liver grafts.

Background & Aims: The steatotic grafts have been applied in liver transplantation frequently owing to the high incidence of non-alcoholic fatty liver disease. However, fatty livers are vulnerable to graft injury. Myeloid-derived suppressor cell (MDSC) recruitment during liver graft injury promotes tumour recurrence. Lipid metabolism exerts the immunological influence on MDSCs in tumour progression. Here, we aimed to explore the role and mechanism of inflammasome activation in MDSCs induced by lipid metabolism during fatty liver graft injury and the subsequent effects on tumour recurrence. Methods: MDSC populations and nucleotide-binding oligomerisation domain-like receptor family pyrin domain containing 3 (NLRP3) inflammasome levels were investigated in a clinical cohort and a rat liver transplantation model. The mechanism of NLRP3 activation by specific fatty acids was explored in mouse hepatic ischaemia/reperfusion injury (IRI) with tumour recurrence model and in vitro studies. Results: MDSC populations and NLRP3 levels were increased with higher tumour recurrent rate in patients using steatotic grafts. NLRP3 was upregulated in MDSCs with lipid accumulation post mouse fatty liver IRI. Mechanistically, arachidonic acid was discovered to activate NLRP3 inflammasome in MDSCs through fatty acid transport protein 2 (FATP2), which was identified by screening lipid uptake receptors. The mitochondrial dysfunction with enhanced reactive oxygen species bridged arachidonic acid uptake and NLRP3 activation in MDSCs, which subsequently stimulated CD4+ T cells producing more IL-17 in fatty liver IRI. Blockade of FATP2 inhibited NLRP3 activation in MDSCs, IL-17 production in CD4+ T cells, and the tumour recurrence post fatty liver IRI. Conclusions: During fatty liver graft injury, arachidonic acid activated NLRP3 inflammasome in MDSCs through FATP2, which subsequently stimulated CD4+ T cells producing IL-17 to promote tumour recurrence post transplantation. Impact and implications: The high incidence of non-alcoholic fatty liver disease resulted in the frequent application of steatotic donors in liver transplantation. Our data showed that the patients who underwent liver transplantation using fatty grafts experienced higher tumour recurrence. We found that arachidonic acid activated NLRP3 inflammasome in MDSCs through FATP2 during fatty liver graft injury, which led to more IL-17 secretion of CD4+ T cells and promoted tumour recurrence post transplantation. The inflammasome activation by aberrant fatty acid metabolism in MDSCs bridged the acute-phase fatty liver graft injury and liver tumour recurrence.

High prevalence of de novo metabolic dysfunction-associated fatty liver disease after liver transplantation and the role of controlled attenuation parameter.

BACKGROUND & AIMS: Although non-alcoholic fatty liver disease (NAFLD) remains an uncommon indication for liver transplantation (LT) in the Chinese, the prevalence of NAFLD is increasing. We aimed to determine the prevalence of de novo steatosis and metabolic dysfunction-associated fatty liver disease (MAFLD) after LT. METHODS: Transient elastography assessment for liver stiffness and controlled attenuation parameter (CAP) were performed after LT in 549 patients at median time of 77 months from LT. CAP was compared with implant liver biopsy, and also validated in 42 patients with post-LT liver biopsy. Longitudinal history including diabetes mellitus (DM), dyslipidemia, hypertension, and immunosuppressive regimen were recorded. RESULTS: The optimal cut-off level of CAP for diagnosing at least mild (≥ S1) and moderate-to-severe steatosis (≥ S2/3) was 266 and 293 dB/m respectively, with AUROC of 0.740 and 0.954 respectively. Using this newly derived cut-off, 28.9% patients have de novo NAFLD, of which 95.6% fulfilled the criteria for MAFLD. After multivariate analysis, BMI (HR 1.34), DM (HR 2.01), hypertension (HR 2.03), HDL-cholesterol (HR 0.25), LDL-cholesterol (HR 1.5) and cryptogenic cirrhosis (HR 4.85) were associated with the development of S2/3 graft steatosis. de novo NAFLD was associated with higher incidence of new-onset hypertension (p < 0.001), graft dysfunction (defined as ALT > 40 U/L; p = 0.008), but not associated with graft fibrosis (defined as liver stiffness > 12 kPa; p = 0.761). CONCLUSION: Although NAFLD remains an uncommon primary liver disease indication for LT in Chinese patients, post-transplant de novo graft steatosis is common and the majority is classified as MAFLD. Development of graft steatosis is not associated with an increase in graft fibrosis but was associated with worse metabolic control and graft dysfunction. Routine CAP measurement to detect de novo graft steatosis should be considered after LT regardless of the primary indication of LT.

Post-transplant inflammatory cytokine signature adds value for predicting tumor recurrence after liver transplantation for hepatocellular carcinoma.

BACKGROUND: Cytokines are key regulators of post-transplant inflammation responses which reconstitute post-transplant hepatic and systemic environments to influence the likelihood of tumor relapse. This study investigated the prognostic value of post-transplant cytokines on tumor recurrence after liver transplantation (LT) for hepatocellular carcinoma (HCC). METHODS: A retrospective analysis was conducted in prospectively collected 150 adult HCC patients who received liver transplantation from 1997 to 2015. The post-transplant 41 inflammatory cytokines were quantified by multiplexing analysis and determined their prognostic value for predicting post-LT tumor recurrence by receiver operative characteristic analysis. A prediction model for post-LT tumor recurrence was generated by the logistic regression and internally validated Bootstrapping and compared with external prediction models. RESULTS: Post-transplant circulating CCL11, IFNα2, and IL17A cytokines were identified to be significant predictors of post-LT tumor recurrence and survival. A prediction score composed of the post-transplant 3-cytokine (P3C) signature, UCSF criteria, and pre-LT AFP was established. The P3C-UCSF-AFP score significantly predicted post-LT tumor recurrence and poor survival both in deceased donor liver transplantation (DDLT) and living donor liver transplantation (LDLT). The P3C-UCSF-AFP score was validated to significantly predict post-LT 2-year and 5-year tumor recurrence, outperforming the RETREAT score, French AFP model, up-to-seven, UCSF criteria, and Milan criteria. Importantly, the P3C-UCSF-AFP score could cost-effectively stratify high-risk recipients subjected to a refinement of post-recurrence survival. CONCLUSION: The integrated P3C-UCSF-AFP score not only compensated for the pre-LT unpredictability and predicted post-LT tumor recurrence accurately, but also guided the clinical refinements of post-LT surveillance and therapeutic strategies in transplant oncology.

A machine learning model for colorectal liver metastasis post-hepatectomy prognostications.

Background: Currently, surgical resection is the mainstay for colorectal liver metastases (CRLM) management and the only potentially curative treatment modality. Prognostication tools can support patient selection for surgical resection to maximize therapeutic benefit. This study aimed to develop a survival prediction model using machine learning based on a multicenter patient sample in Hong Kong. Methods: Patients who underwent hepatectomy for CRLM between 1 January 2009 and 31 December 2018 in four hospitals in Hong Kong were included in the study. Survival analysis was performed using Cox proportional hazards (CPH). A stepwise selection on Cox multivariable models with Least Absolute Shrinkage and Selection Operator (LASSO) regression was applied to a multiply-imputed dataset to build a prediction model. The model was validated in the validation set, and its performance was compared with that of Fong Clinical Risk Score (CRS) using concordance index. Results: A total of 572 patients were included with a median follow-up of 3.6 years. The full models for overall survival (OS) and recurrence-free survival (RFS) consist of the same 8 established and novel variables, namely colorectal cancer nodal stage, CRLM neoadjuvant treatment, Charlson Comorbidity Score, pre-hepatectomy bilirubin and carcinoembryonic antigen (CEA) levels, CRLM largest tumor diameter, extrahepatic metastasis detected on positron emission-tomography (PET)-scan as well as KRAS status. Our CRLM Machine-learning Algorithm Prognostication model (CMAP) demonstrated better ability to predict OS (C-index =0.651), compared with the Fong CRS for 1-year (C-index =0.571) and 5-year OS (C-index =0.574). It also achieved a C-index of 0.651 for RFS. Conclusions: We present a promising machine learning algorithm to individualize prognostications for patients following resection of CRLM with good discriminative ability.

Novel Benchmark for Adult-to-Adult Living-donor Liver Transplantation: Integrating Eastern and Western Experiences.

OBJECTIVE: To define benchmark values for adult-to-adult living-donor liver transplantation (LDLT). BACKGROUND: LDLT utilizes living-donor hemiliver grafts to expand the donor pool and reduce waitlist mortality. Although references have been established for donor hepatectomy, no such information exists for recipients to enable conclusive quality and comparative assessments. METHODS: Patients undergoing LDLT were analyzed in 15 high-volume centers (≥10 cases/year) from 3 continents over 5 years (2016-2020), with a minimum follow-up of 1 year. Benchmark criteria included a Model for End-stage Liver Disease ≤20, no portal vein thrombosis, no previous major abdominal surgery, no renal replacement therapy, no acute liver failure, and no intensive care unit admission. Benchmark cutoffs were derived from the 75th percentile of all centers' medians. RESULTS: Of 3636 patients, 1864 (51%) qualified as benchmark cases. Benchmark cutoffs, including posttransplant dialysis (≤4%), primary nonfunction (≤0.9%), nonanastomotic strictures (≤0.2%), graft loss (≤7.7%), and redo-liver transplantation (LT) (≤3.6%), at 1-year were below the deceased donor LT benchmarks. Bile leak (≤12.4%), hepatic artery thrombosis (≤5.1%), and Comprehensive Complication Index (CCI ® ) (≤56) were above the deceased donor LT benchmarks, whereas mortality (≤9.1%) was comparable. The right hemiliver graft, compared with the left, was associated with a lower CCI ® score (34 vs 21, P < 0.001). Preservation of the middle hepatic vein with the right hemiliver graft had no impact neither on the recipient nor on the donor outcome. Asian centers outperformed other centers with CCI ® score (21 vs 47, P < 0.001), graft loss (3.0% vs 6.5%, P = 0.002), and redo-LT rates (1.0% vs 2.5%, P = 0.029). In contrast, non-benchmark low-volume centers displayed inferior outcomes, such as bile leak (15.2%), hepatic artery thrombosis (15.2%), or redo-LT (6.5%). CONCLUSIONS: Benchmark LDLT offers a valuable alternative to reduce waitlist mortality. Exchange of expertise, public awareness, and centralization policy are, however, mandatory to achieve benchmark outcomes worldwide.

The Landscape of Aberrant Alternative Splicing Events in Steatotic Liver Graft Post Transplantation via Transcriptome-Wide Analysis.

The application of steatotic liver graft has been increased significantly due to the severe donor shortage and prevalence of non-alcoholic fatty liver disease. However, steatotic donor livers are vulnerable to acute phase inflammatory injury, which may result in cancer recurrence. Alternative splicing events (ASEs) are critical for diverse transcriptional variants in hepatocellular carcinoma (HCC). Here, we aimed to depict the landscape of ASEs, as well as to identify the differential ASEs in steatotic liver graft and their association with tumor recurrence after transplantation. The overall portrait of intragraft transcripts and ASEs were elucidated through RNA sequencing with the liver graft biopsies from patients and rat transplant models. Various differential ASEs were identified in steatotic liver grafts. CYP2E1, ADH1A, CYP2C8, ADH1C, and HGD, as corresponding genes to the common pathways involved differential ASEs in human and rats, were significantly associated with HCC patients' survival. The differential ASEs related RNA-binding proteins (RBPs) were enriched in metabolic pathways. The altered immune cell distribution, particularly macrophages and neutrophils, were perturbated by differential ASEs. The cancer hallmarks were enriched in steatotic liver grafts and closely associated with differential ASEs. Our work identified the differential ASE network with metabolic RBPs, immune cell distribution, and cancer hallmarks in steatotic liver grafts. We verified the link between steatotic liver graft injury and tumor recurrence at post-transcriptional level, offered new evidence to explore metabolism and immune responses, and provided the potential prognostic and therapeutic markers for tumor recurrence.

Defining the surgical management for non-colorectal liver metastases.

BACKGROUND: Surgical resection is indicated for resectable colorectal liver metastases (CLM), but it is controversial for non-colorectal liver metastases (NCLM). This study aimed to compare survival outcomes of patients with resection of NCLM versus CLM and to identify prognostic factors for resection of NCLM. METHODS: Consecutive patients who underwent surgical resection of liver metastases at Queen Mary Hospital, Hong Kong from January 1989 to December 2019 were retrospectively reviewed. Patients with resected NCLM were compared to those with CLM. Overall and recurrence-free survival were determined. Subgroup analyses with patients grouped according to the year of liver resection, from 1989 to 2004 and from 2005 to 2019, were conducted. Univariate and multivariate analyses were performed to identify prognostic factors. RESULTS: Among 674 patients included, 151 (22.4%) had NCLM while 523 (77.6%) had CLM. There were no statistically significant differences in median overall survival (65.2 vs 43.6 months, p = 0.555) and recurrence-free survival (12.5 vs 11.7 months, p = 0.425). The 1-year, 3-year, 5-year and 10-year overall survival rates were 89.8% vs 91.5%, 59.4% vs 58.8%, 50.6% vs 38.7% and 34.1% vs 26.3% in NCLM and CLM groups, respectively. Subgroup analyses demonstrated no statistically significant difference in overall survival between resection of NCLM versus CLM in both time intervals. In the NCLM group, better overall survival was found in liver metastasis of gastrointestinal stromal tumour (GIST) origin (hazard ratio (HR) 0.138, p = 0.003) and with a longer time interval from resection of primary tumour to resection of NCLM (HR 0.982, p = 0.042). Poor prognostic factors were presence of blood transfusion (HR 5.588, p = 0.013) and post-operative complications of Clavien-Dindo Grade IIIa or above (HR 74.853, p = 0.003). CONCLUSIONS: Surgical resection of NCLM had comparable survival outcomes with CLM. With appropriate patient selection, the indication of liver resection could be expanded to NCLM.

Isoformic PD-1-mediated immunosuppression underlies resistance to PD-1 blockade in hepatocellular carcinoma patients.

OBJECTIVE: Immune checkpoint blockade (ICB) has improved cancer treatment, yet why most hepatocellular carcinoma (HCC) patients are resistant to PD-1 ICB remains elusive. Here, we elucidated the role of a programmed cell death protein 1 (PD-1) isoform, Δ42PD-1, in HCC progression and resistance to nivolumab ICB. DESIGN: We investigated 74 HCC patients in three cohorts, including 41 untreated, 28 treated with nivolumab and 5 treated with pembrolizumab. Peripheral blood mononuclear cells from blood samples and tumour infiltrating lymphocytes from tumour tissues were isolated for immunophenotyping. The functional significance of Δ42PD-1 was explored by single-cell RNA sequencing analysis and validated by functional and mechanistic studies. The immunotherapeutic efficacy of Δ42PD-1 monoclonal antibody was determined in HCC humanised mouse models. RESULTS: We found distinct T cell subsets, which did not express PD-1 but expressed its isoform Δ42PD-1, accounting for up to 71% of cytotoxic T lymphocytes in untreated HCC patients. Δ42PD-1+ T cells were tumour-infiltrating and correlated positively with HCC severity. Moreover, they were more exhausted than PD-1+ T cells by single T cell and functional analysis. HCC patients treated with anti-PD-1 ICB showed effective PD-1 blockade but increased frequencies of Δ42PD-1+ T cells over time especially in patients with progressive disease. Tumour-infiltrated Δ42PD-1+ T cells likely sustained HCC through toll-like receptors-4-signalling for tumourigenesis. Anti-Δ42PD-1 antibody, but not nivolumab, inhibited tumour growth in three murine HCC models. CONCLUSION: Our findings not only revealed a mechanism underlying resistance to PD-1 ICB but also identified anti-Δ42PD-1 antibody for HCC immunotherapy.

Sequential transarterial chemoembolisation and stereotactic body radiotherapy followed by immunotherapy as conversion therapy for patients with locally advanced, unresectable hepatocellular carcinoma (START-FIT): a single-arm, phase 2 trial.

BACKGROUND: The synergy between locoregional therapies and immune checkpoint inhibitors has not been investigated as conversion therapy for unresectable hepatocellular carcinoma. We aimed to investigate the activity of sequential transarterial chemoembolisation (TACE) and stereotactic body radiotherapy followed by avelumab (an anti-PD-L1 drug) for locally advanced, unresectable hepatocellular carcinoma. METHODS: START-FIT was a single-arm, phase 2 trial in patients with locally advanced hepatocellular carcinoma who were not suitable for curative treatment, conducted in two hospitals in Hong Kong and one in Shenzhen, China. Eligible patients were those aged 18 years or older with an Eastern Cooperative Oncology Group performance status 0-1, Child-Pugh liver function score A5 to B7, tumour size of at least 5 cm, a maximum of three tumour lesions, and adequate hepatic, renal, and bone marrow function. Participants received TACE on day 1, followed by stereotactic body radiotherapy (27·5-40·0 Gy in five fractions) at day 28. Avelumab (10 mg/kg) was administered 14 days following stereotactic body radiotherapy and every 2 weeks thereafter. The primary endpoint was the proportion of patients deemed amenable to curative treatment, defined as those who had a sustained complete or partial treatment response for at least 2 months and if curative treatment could be performed (ie, resection, radiofrequency ablation, or transplantation), analysed by intention to treat. Safety was also analysed in the intention-to-treat population. This trial is registered with ClinicalTrials.gov (NCT03817736) and has been completed. FINDINGS: Between March 18, 2019, and Jan 27, 2021, 33 patients (32 [97%] men and one [3%] woman) were enrolled. The median sum of the largest diameters of lesions was 15·1 cm (IQR 8·3-14·9). 21 (64%) patients had macrovascular invasion (hepatic vein [n=13], branched portal vein [n=3], or both [n=5]). Median follow-up was 17·2 months (IQR 7·8-25·8). 18 (55%) patients were deemed amenable to curative treatment: four (12%) of 33 patients had curative treatment (resection [n=2] or radiofrequency ablation [n=2]), and 14 (42%) had a radiological complete response and opted for close surveillance. 11 (33%) of 33 patients had treatment-related adverse events that were grade 3 or worse. The most common treatment-related grade 3 or worse adverse event was transient increase in alanine aminotransferase or aspartate aminotransferase (five [15%]) after TACE. Five (15%) patients developed immune-related adverse events of grade 3 or worse (three had hepatitis, two had dermatitis). INTERPRETATION: To our knowledge, this is the first prospective trial using the combination of immunotherapy and locoregional treatment as conversion therapy for locally advanced unresectable hepatocellular carcinoma, with promising results. Future randomised trials with larger cohorts of patients are warranted. FUNDING: Merck.

Postoperative Plasmacytoid Dendritic Cells Secrete IFNα to Promote Recruitment of Myeloid-Derived Suppressor Cells and Drive Hepatocellular Carcinoma Recurrence.

Patients with hepatocellular carcinoma (HCC) confront a high incidence of tumor recurrence after curative surgical resection. Hepatic ischemia-reperfusion injury (IRI) is the major consequence of surgical stress during hepatectomy. Although it has been suggested that hepatic IRI-induced immunosuppression could contribute to tumor relapse after surgery, the underlying mechanisms have not been fully defined. Here, using a multiplex cytokine array, we found that levels of postoperative IFNα serve as an independent risk factor for tumor recurrence in 100 patients with HCC with curative hepatectomy. Plasmacytoid dendritic cells (pDC), the major source of IFNα, were activated after surgery and correlated with poor disease-free survival. Functionally, IFNα was responsible for mobilization of myeloid-derived suppressor cells (MDSC) following hepatic IRI. Conditioned medium from IFNα-treated hepatocytes mediated the migration of MDSCs in vitro. Mechanistically, IFNα upregulated IRF1 to promote hepatocyte expression of CX3CL1, which subsequently recruited CX3CR1+ monocytic MDSCs. Knockdown of Irf1 or Cx3cl1 in hepatocytes significantly inhibited the accumulation of monocytic MDSCs in vivo. Therapeutically, elimination of pDCs, IFNα, or CX3CR1 could restore the tumor-killing activity of CD8+ T cells, hence limiting tumor growth and lung metastasis following hepatic IRI. Taken together, these data suggest that IFNα-producing pDCs drive CX3CR1+ MDSC recruitment via hepatocyte IRF1/CX3CL1 signaling and lead to tumor recurrence after hepatectomy in HCC. Targeting pDCs and the IFNα/CX3CL1/CX3CR1 axis could inhibit surgical stress-induced HCC recurrence by attenuating postoperative immunosuppression. SIGNIFICANCE: IFNα secreted by plasmacytoid dendritic cells drives postoperative immunosuppression and early recurrence of hepatocellular carcinoma, providing new biomarkers and therapeutic targets to improve patient outcomes after surgical resection.

Long-term survival in colorectal liver metastasis.

INTRODUCTION: Liver resection is the best treatment option for patients with resectable colorectal liver metastasis (CRLM). A 10-year follow-up can reflect the true curative potential of resection. This retrospective study investigated factors for long-term survival of CRLM patients. METHOD: Data of patients who underwent liver resection for CRLM without extrahepatic disease from 1990 to 2012 at our hospital were reviewed. Patients who survived for > 10 years were compared with those who survived for < 10 years. RESULTS: Totally, 315 patients were included in the study. They were divided into 2 groups: < 10-year group and > 10-year group. Patients in the < 10-year group had more tumor nodules (P = 0.016), more bilobar involvement (P = 0.004), narrower resection margin (P < 0.001), and worse disease-free and overall survival (P < 0.001). On multivariate analysis, low preoperative hemoglobin level, large number of tumor nodules, and bilobar involvement were poor prognostic factors for overall survival, while adjuvant chemotherapy was a favorable factor. Further analysis of patients with bilobar disease showed that perioperative blood transfusion was a poor prognostic factor for overall survival while adjuvant chemotherapy was a favorable one. In patients with multiple bilobar tumor nodules, adjuvant chemotherapy had a positive impact on disease-free survival and overall survival. CONCLUSIONS: Patients who survived for > 10 years after liver resection for CRLM tended to have normal preoperative hemoglobin level, unilobar disease, fewer tumor nodules, and have received adjuvant chemotherapy. Adjuvant chemotherapy favorably affected long-term survival of CRLM patients.

Impact of Tumour Biology on Outcomes of Radical Therapy for Hepatocellular Carcinoma Oligo-Recurrence after Liver Transplantation.

It is uncertain whether tumour biology affects radical treatment for post-transplant hepatocellular carcinoma (HCC) oligo-recurrence, i.e. recurrence limited in numbers and locations amendable to radical therapy. We conducted a retrospective study on 144 patients with post-transplant HCC recurrence. Early recurrence within one year after transplant (HR 2.53, 95% CI 1.65−3.88, p < 0.001), liver recurrence (HR 1.74, 95% CI 1.12−2.68, p = 0.01) and AFP > 200 ng/mL upon recurrence (HR 1.62, 95% CI 1.04−2.52, p = 0.03) predicted mortality following recurrence. In patients with early recurrence and liver recurrence, radical treatment was associated with improved post-recurrence survival (early recurrence: median 18.2 ± 1.5 vs. 9.2 ± 1.5 months, p < 0.001; liver recurrence: median 28.0 ± 4.5 vs. 11.6 ± 2.0, p < 0.001). In patients with AFP > 200 ng/mL, improvement in survival did not reach statistical significance (median 18.2 ± 6.5 vs. 8.8 ± 2.2 months, p = 0.13). Survival benefits associated with radical therapy were reduced in early recurrence (13.6 vs. 9.0 months) and recurrence with high AFP (15.4 vs. 9.3 months) but were similar among patients with and without liver recurrence (16.9 vs. 16.4 months). They were also diminished in patients with multiple biological risk factors (0 risk factor: 29.0 months; 1 risk factor: 19.7 months; 2−3 risk factors: 3.4 months): The survival benefit following radical therapy was superior in patients with favourable biological recurrence but was also observed in patients with poor tumour biology. Treatment decisions should be individualised considering the oncological benefits, quality of life gain and procedural morbidity.

HFE promotes mitotic cell division through recruitment of cytokinetic abscission machinery in hepatocellular carcinoma.

HFE (Hemochromatosis) is a conventional iron level regulator and its loss of function due to gene mutations increases the risk of cancers including hepatocellular carcinoma (HCC). Likewise, studies focusing on HFE overexpression in cancers are all limited to linking up these events as a consequence of iron level deregulation. No study has explored any iron unrelated role of HFE in cancers. Here, we first reported HFE as an oncogene in HCC and its undescribed function on promoting abscission in cytokinesis during mitotic cell division, independent of its iron-regulating ability. Clinical analyses revealed HFE upregulation in tumors linking to large tumor size and poor prognosis. Functionally and mechanistically, HFE promoted cytokinetic abscission via facilitating ESCRT abscission machinery recruitment to the abscission site through signaling a novel HFE/ALK3/Smads/LIF/Hippo/YAP/YY1/KIF13A axis. Pharmacological blockage of HFE signaling axis impeded tumor phenotypes in vitro and in vivo. Our data on HFE-driven HCC unveiled a new mechanism utilized by cancer cells to propel rapid cell division. This study also laid the groundwork for tumor intolerable therapeutics development given the high cytokinetic dependency of cancer cells and their vulnerability to cytokinetic blockage.