Combining a deep learning model with clinical data better predicts hepatocellular carcinoma behavior following surgery

Hepatocellular carcinoma (HCC) is among the most common cancers worldwide, and tumor recurrence following liver resection or transplantation is one of the highest contributors to mortality in HCC patients after surgery. Using artificial intelligence (AI), we developed an interdisciplinary model to predict HCC recurrence and patient survival following surgery. We collected whole-slide H&E images, clinical variables, and follow-up data from 300 patients with HCC who underwent transplant and 169 patients who underwent resection at the Cleveland Clinic. A deep learning model was trained to predict recurrence-free survival (RFS) and disease-specific survival (DSS) from the H&E-stained slides. Repeated cross-validation splits were used to compute robust C-index estimates, and the results were compared to those obtained by fitting a Cox proportional hazard model using only clinical variables. While the deep learning model alone was predictive of recurrence and survival among patients in both cohorts, integrating the clinical and histologic models significantly increased the C-index in each cohort. In every subgroup analyzed, we found that a combined clinical and deep learning model better predicted post-surgical outcome in HCC patients compared to either approach independently.

Early Onset Intrahepatic Cholangiocarcinoma: Clinical Characteristics, Oncological Outcomes, and Genomic/Transcriptomic Features

INTRODUCTION

Data on clinical characteristics and disease-specific prognosis among patients with early onset intrahepatic cholangiocarcinoma (ICC) are currently limited.

METHODS

Patients undergoing hepatectomy for ICC between 2000 and 2020 were identified by using a multi-institutional database. The association of early (≤50 years) versus typical onset (>50 years) ICC with recurrence-free (RFS) and disease-specific survival (DSS) was assessed in the multi-institutional database and validated in an external cohort. The genomic and transcriptomic profiles of early versus late onset ICC were analyzed by using the Total Cancer Genome Atlas (TCGA) and Memorial Sloan Kettering Cancer Center databases.

RESULTS

Among 971 patients undergoing resection for ICC, 22.7% (n = 220) had early-onset ICC. Patients with early-onset ICC had worse 5-year RFS (24.1% vs. 29.7%, p < 0.05) and DSS (36.5% vs. 48.9%, p = 0.03) compared with patients with typical onset ICC despite having earlier T-stage tumors and lower rates of microvascular invasion. In the validation cohort, patients with early-onset ICC had worse 5-year RFS (7.4% vs. 20.5%, p = 0.002) compared with individuals with typical onset ICC. Using the TCGA cohort, 652 and 266 genes were found to be upregulated (including ATP8A2) and downregulated (including UTY and KDM5D) in early versus typical onset ICC, respectively. Genes frequently implicated as oncogenic drivers, including CDKN2A, IDH1, BRAF, and FGFR2 were infrequently mutated in the early-onset ICC patients.

CONCLUSIONS

Early-onset ICC has distinct clinical and genomic/transcriptomic features. Morphologic and clinicopathologic characteristics were unable to fully explain differences in outcomes among early versus typical onset ICC patients. The current study offers a preliminary landscape of the molecular features of early-onset ICC.

Impact of Back-to-Base Normothermic Machine Perfusion on Complications and Costs: A Multi-Center, Real-World Risk-Matched Analysis

OBJECTIVE

Assess cost and complication outcomes after liver transplantation (LT) using normothermic machine perfusion (NMP).

SUMMARY BACKGROUND DATA

End-ischemic NMP is often used to aid logistics, yet its' impact on outcomes after LT remains unclear, as does its' true impact on costs associated with transplantation.

METHODS

Deceased donor liver recipients at two centers (1/1/2019-6/30/2023) were included. Retransplants, splits and combined grafts were excluded. End-ischemic NMP (OrganOx-Metra®) was implemented 10/2022 for extended-criteria DBDs, all DCDs and logistics. NMP-cases were matched 1:2 with cold storage controls (SCS) using the Balance-of-Risk (DBD-grafts) and UK-DCD Score (DCD-grafts).

RESULTS

Overall, 803 transplantations were included, 174 (21.7%) receiving NMP. Matching was achieved between 118 NMP-DBDs with 236 SCS; and 37 NMP-DCD with 74 corresponding SCS. For both graft types, median inpatient comprehensive complications index (CCI) values were comparable between groups. DCD-NMP grafts experienced reduced cumulative 90-day CCI (27.6 vs. 41.9, P=0.028). NMP also reduced the need for early relaparotomy and renal-replacement-therapy, with subsequently less-frequent major complications (Clavien-Dindo >IVa). This effect was more pronounced in DCD-transplants. NMP had no protective effect on early biliary complications. Organ acquisition/preservation costs were higher with NMP, yet NMP-treated grafts had lower 90-day pre-transplant costs in context of shorter waiting-list times. Overall costs were comparable for both cohorts.

CONCLUSIONS

This is the first risk-adjusted outcome and cost analysis comparing NMP and SCS. In addition to logistical benefits, NMP was associated with a reduction in relaparotomy and bleeding in DBD-grafts, and overall complications and post-LT renal-replacement for DCDs. While organ acquisition/preservation was more costly with NMP, overall 90-day-healthcare costs-per-transplantation were comparable.

Optimal policy tree to assist in adjuvant therapy decision-making after resection of colorectal liver metastases

BACKGROUND

Although systemic postoperative therapy after surgery for colorectal liver metastases is generally recommended, the benefit of adjuvant chemotherapy has been debated. We used machine learning to develop a decision tree and define which patients may benefit from adjuvant chemotherapy after hepatectomy for colorectal liver metastases.

METHODS

Patients who underwent curative-intent resection for colorectal liver metastases between 2000 and 2020 were identified from an international multi-institutional database. An optimal policy tree analysis was used to determine the optimal assignment of the adjuvant chemotherapy to subgroups of patients for overall survival and recurrence-free survival.

RESULTS

Among 1,358 patients who underwent curative-intent resection of colorectal liver metastases, 1,032 (76.0%) received adjuvant chemotherapy. After a median follow-up of 28.7 months (interquartile range 13.7-52.0), 5-year overall survival was 67.5%, and 3-year recurrence-free survival was 52.6%, respectively. Adjuvant chemotherapy was associated with better recurrence-free survival (3-year recurrence-free survival: adjuvant chemotherapy, 54.4% vs no adjuvant chemotherapy, 46.8%; P < .001) but no overall survival significant improvement (5-year overall survival: adjuvant chemotherapy, 68.1% vs no adjuvant chemotherapy, 65.7%; P = .15). Patients were randomly allocated into 2 cohorts (training data set, n = 679, testing data set, n = 679). The random forest model demonstrated good performance in predicting counterfactual probabilities of death and recurrence relative to receipt of adjuvant chemotherapy. According to the optimal policy tree, patient demographics, secondary tumor characteristics, and primary tumor characteristics defined the subpopulation that would benefit from adjuvant chemotherapy.

CONCLUSION

A novel artificial intelligence methodology based on patient, primary tumor, and treatment characteristics may help clinicians tailor adjuvant chemotherapy recommendations after colorectal liver metastases resection.

Impact of autotransfusion on recurrence of colorectal cancer liver metastasis: Long-term follow-up of patients undergoing curative intent hepatectomy

INTRODUCTION

Colorectal cancer liver metastasis (CRLM) occurs in upto 50% of cases and drives patient outcomes. Up-front liver resection is the treatment of choice in resectable cases. There is no consensus yet established as to the safety of intraoperative autotransfusion in liver resection for CRLM.

METHODS

Patients undergoing curative-intent hepatectomy for CRLM at a single quaternary-care institution from 1999 to 2016 were included. Demographics, surgical variables, Fong Clinical Risk Score (FCRS), use of intraoperative auto and/or allotransfusion, and survival data were analyzed. Propensity score matching (PSM) was performed accounting for allotransfusion, extent of hepatectomy, FCRS, and systemic treatment regimens.

RESULTS

Three-hundred sixteen patients were included. The median follow-up was 10.4 years (7.8-14.1 years). The median recurrence-free survival (RFS) and overall survival (OS) in all patients were 1.6 years (interquartile range: 0.63-6.6 years) and 4.4 years (2.1-8.7), respectively.  Before PSM, there was a significantly reduced RFS in the autotransfusion group (0.96 vs. 1.73 years, p = 0.20). There was no difference in OS (4.11 vs. 4.44 years, p = 0.118). Patients in groups of FCRS 0-2 and 3-5 both had reduced RFS when autotransfusion was used (p = 0.005). This reduction in RFS was further found when comparing autotransfusion versus no autotransfusion within the FCRS 0-2 group and within the FCRS 3-5 group (p = 0.027). On Cox-regression analysis, autotransfusion (hazard ratio = 1.423, 1.028-2.182, p = 0.015) remained predictive of RFS. After PSM, there were no differences in FCRS (p = 0.601), preoperative hemoglobin (p = 0.880), allotransfusion (p = 0.130), adjuvant chemotherapy (p = 1.000), immunotherapy (p = 0.172), tumor grade (p = 1.000), use of platinum-based chemotherapy (p = 0.548), or type of hepatic resection (p = 0.967). After matching, there was a higher rate of recurrence with autotransfusion (69.0% vs. 47.6%, p = 0.046). There was also a reduced time to recurrence in the autotransfusion group compared with the group without (p = 0.006). There was no difference in OS after PSM (p = 0.262).

CONCLUSION

Autotransfusion may adversely affect recurrence in liver resection for CRLM. Until further studies clarify this risk profile, the use of intraoperative autotransfusion should be critically assessed on a case-by-case basis only when other resuscitation options are not available.

Circulating Tumor DNA Profiling in Liver Transplant for Hepatocellular Carcinoma, Cholangiocarcinoma, and Colorectal Liver Metastases: A Programmatic Proof of Concept

INTRODUCTION

Circulating tumor DNA (ctDNA) is emerging as a promising, non-invasive diagnostic and surveillance biomarker in solid organ malignancy. However, its utility before and after liver transplant (LT) for patients with primary and secondary liver cancers is still underexplored.

METHODS

Patients undergoing LT for hepatocellular carcinoma (HCC), cholangiocarcinoma (CCA), and colorectal liver metastases (CRLM) with ctDNA testing were included. CtDNA testing was conducted pre-transplant, post-transplant, or both (sequential) from 11/2019 to 09/2023 using Guardant360, Guardant Reveal, and Guardant360 CDx.

RESULTS

21 patients with HCC (n = 9, 43%), CRLM (n = 8, 38%), CCA (n = 3, 14%), and mixed HCC/CCA (n = 1, 5%) were included in the study. The median follow-up time was 15 months (range: 1-124). The median time from pre-operative testing to surgery was 3 months (IQR: 1-4; range: 0-5), and from surgery to post-operative testing, it was 9 months (IQR: 2-22; range: 0.4-112). A total of 13 (62%) patients had pre-transplant testing, with 8 (62%) having ctDNA detected (ctDNA+) and 5 (32%) not having ctDNA detected (ctDNA-). A total of 18 (86%) patients had post-transplant testing, 11 (61%) of whom were ctDNA+ and 7 (33%) of whom were ctDNA-. The absolute recurrence rates were 50% (n = 5) in those who were ctDNA+ vs. 25% (n = 1) in those who were ctDNA- in the post-transplant setting, though this difference was not statistically significant (p = 0.367). Six (29%) patients (HCC = 3, CCA = 1, CRLM = 2) experienced recurrence with a median recurrence-free survival of 14 (IQR: 6-40) months. Four of these patients had positive post-transplant ctDNA collected following diagnosis of recurrence, while one patient had positive post-transplant ctDNA collected preceding recurrence. A total of 10 (48%) patients had sequential ctDNA testing, of whom n = 5 (50%) achieved ctDNA clearance (+/-). The remainder were ctDNA+/+ (n = 3, 30%), ctDNA-/- (n = 1, 10%), and ctDNA-/+ (n = 1, 11%). Three (30%) patients showed the acquisition of new genomic alterations following transplant, all without recurrence. Overall, the median tumor mutation burden (TMB) decreased from 1.23 mut/Mb pre-transplant to 0.00 mut/Mb post-transplant.

CONCLUSIONS

Patients with ctDNA positivity experienced recurrence at a higher rate than the ctDNA- patients, indicating the potential role of ctDNA in predicting recurrence after curative-intent transplant. Based on sequential testing, LT has the potential to clear ctDNA, demonstrating the capability of LT in the treatment of systemic disease. Transplant providers should be aware of the potential of donor-derived cell-free DNA and improved approaches are necessary to address such concerns.

Plasma metabolomic differences in early-onset compared to average-onset colorectal cancer

Deleterious effects of environmental exposures may contribute to the rising incidence of early-onset colorectal cancer (eoCRC). We assessed the metabolomic differences between patients with eoCRC, average-onset CRC (aoCRC), and non-CRC controls, to understand pathogenic mechanisms. Patients with stage I-IV CRC and non-CRC controls were categorized based on age ≤ 50 years (eoCRC or young non-CRC controls) or  ≥ 60 years (aoCRC or older non-CRC controls). Differential metabolite abundance and metabolic pathway analyses were performed on plasma samples. Multivariate Cox proportional hazards modeling was used for survival analyses. All P values were adjusted for multiple testing (false discovery rate, FDR P < 0.15 considered significant). The study population comprised 170 patients with CRC (66 eoCRC and 104 aoCRC) and 49 non-CRC controls (34 young and 15 older). Citrate was differentially abundant in aoCRC vs. eoCRC in adjusted analysis (Odds Ratio = 21.8, FDR P = 0.04). Metabolic pathways altered in patients with aoCRC versus eoCRC included arginine biosynthesis, FDR P = 0.02; glyoxylate and dicarboxylate metabolism, FDR P = 0.005; citrate cycle, FDR P = 0.04; alanine, aspartate, and glutamate metabolism, FDR P = 0.01; glycine, serine, and threonine metabolism, FDR P = 0.14; and amino-acid t-RNA biosynthesis, FDR P = 0.01. 4-hydroxyhippuric acid was significantly associated with overall survival in all patients with CRC (Hazards ratio, HR = 0.4, 95% CI 0.3-0.7, FDR P = 0.05). We identified several unique metabolic alterations, particularly the significant differential abundance of citrate in aoCRC versus eoCRC. Arginine biosynthesis was the most enriched by the differentially altered metabolites. The findings hold promise in developing strategies for early detection and novel therapies.

Postoperative morbidity after simultaneous versus staged resection of synchronous colorectal liver metastases: Impact of hepatic tumor burden

BACKGROUND

We sought to characterize the risk of postoperative complications relative to the surgical approach and overall synchronous colorectal liver metastases tumor burden score.

METHODS

Patients with synchronous colorectal liver metastases who underwent curative-intent resection between 2000 and 2020 were identified from an international multi-institutional database. Propensity score matching was employed to control for heterogeneity between the 2 groups. A virtual twins analysis was performed to identify potential subgroups of patients who might benefit more from staged versus simultaneous resection.

RESULTS

Among 976 patients who underwent liver resection for synchronous colorectal liver metastases, 589 patients (60.3%) had a staged approach, whereas 387 (39.7%) patients underwent simultaneous resection of the primary tumor and synchronous colorectal liver metastases. After propensity score matching, 295 patients who underwent each surgical approach were analyzed. Overall, the incidence of postoperative complications was 34.1% (n = 201). Among patients with high tumor burden scores, the surgical approach was associated with a higher incidence of postoperative complications; in contrast, among patients with low or medium tumor burden scores, the likelihood of complications did not differ based on the surgical approach. Virtual twins analysis demonstrated that preoperative tumor burden score was important to identify which subgroup of patients benefited most from staged versus simultaneous resection. Simultaneous resection was associated with better outcomes among patients with a tumor burden score <9 and a node-negative right-sided primary tumor; in contrast, staged resection was associated with better outcomes among patients with node-positive left-sided primary tumors and higher tumor burden score.

CONCLUSION

Among patients with high tumor burden scores, simultaneous resection of the primary tumor and liver metastases was associated with an increased incidence of postoperative complications.

Update to 'A Contemporary Systematic Review on Liver Transplantation for Unresectable Liver Metastasis of Colorectal Cancer'

Colorectal cancer is the second most common cause of cancer-related death worldwide, and half of patients present with colorectal liver metastasis (CRLM). Liver transplant (LT) has emerged as a treatment modality for otherwise unresectable CRLM. Since the publication of the Lebeck-Lee systematic review in 2022, additional evidence has come to light supporting LT for CRLM in highly selected patients. This includes reports of >10-year follow-up with over 80% survival rates in low-risk patients. As these updated reports have significantly changed our collective knowledge, this article is intended to serve as an update to the 2022 systematic review to include the most up-to-date evidence on the subject.

Comparison of Engineered Liver 3D Models and the Role of Oxygenation for Patient-Derived Tumor Cells and Immortalized Cell Lines Cocultured with Tumor Stroma in the Detection of Hepatotoxins

In metabolically active tumors, responses of cells to drugs are heavily influenced by oxygen availability via the surrounding vasculature alongside the extracellular matrix signaling. The objective of this study is to investigate hepatotoxicity by replicating critical features of hepatocellular carcinoma (HCC). This includes replicating 3D structures, metabolic activities, and tumor-specific markers. The internal environment of spheroids comprised of cancerous human patient-derived hepatocytes using microparticles is modulated to enhance the oxygenation state and recreate cell-extracellular matrix interactions. Furthermore, the role of hepatic stellate cells in maintaining hepatocyte survival and function is explored and hepatocytes from two cellular sources (immortalized and patient-derived) to create four formulations with and without microparticles are utilized. To investigate drug-induced changes in metabolism and apoptosis in liver cells, coculture spheroids with and without microparticles are exposed to three hepatotoxic drugs. The use of microparticles increases levels of apoptotic markers in both liver models under drug treatments. This coincides with reduced levels of anti-apoptotic proteins and increased levels of pro-apoptotic proteins. Moreover, cells from different origins undergo apoptosis through distinct apoptotic pathways in response to identical drugs. This 3D microphysiological system offers a viable tool for liver cancer research to investigate mechanisms of apoptosis under different microenvironmental conditions.

Risk assessment in liver transplantation for hepatocellular carcinoma: long-term follow-up of a two-center experience

BACKGROUND

Liver transplantation (LT) is a well-established treatment for hepatocellular carcinoma (HCC), but there are ongoing debates regarding outcomes and selection. This study examines the experience of LT for HCC at a high-volume center.

METHODS

A prospectively maintained database was used to identify HCC patients undergoing LT from 2000-2020 with>3 years follow-up. Data was obtained from the center database and electronic medical records. The Metroticket 2.0 HCC-specific five-year survival scale was calculated for each patient. Kaplan-Meier and Cox-regression analyses were employed assessing survival between groups based on Metroticket score and individual donor and recipient risk factors.

RESULTS

569 patients met criteria. Median follow-up was 96.2 months (8.12 y; IQR 59.9-147.8). Three-year recurrence-free (RFS) and overall survival (OS) were 88.6% (n=504) and 86.6% (n=493). Five-year RFS and OS were 78.9% (n=449) and 79.1% (n=450). Median Metroticket 2.0 score was 0.9 (IQR 0.9-0.95). Tumor size>3 cm (P=0.012), increasing tumor number on imaging (P=0.001) and explant pathology (P<0.001) was associated with recurrence. Transplant within Milan (P<0.001) or UCSF-criteria (P<0.001) had lower recurrence rates. Increasing AFP-values were associated with more HCC-recurrence (P<0.001) and reduced OS (P=0.008). Chemoembolization was predictive of recurrence in the overall population (P=0.043) and in those outside Milan criteria (P=0.038). A receiver-operator curve using Metroticket 2.0 identified an optimal cut-off of projected survival>87.5% for predicting recurrence. This cut-off was able to predict RFS (P<0.001) in the total cohort and predict both, RFS (P=0.007) and OS (P=0.016) outside-Milan. Receipt of donation after brain death (DBD) grafts (55/478, 13%) or living-donor grafts (3/22, 13.6%) experienced better survival rates compared to donation after cardiac death (DCD) grafts (n=15/58, 25.6%, P=0.009). Donor age was associated with a higher HCC-recurrence (P=0.006). Both total ischemia time (TIT)>6hours (P=0.016) and increasing TIT correlated with higher HCC-recurrence (P=0.027). The use of DCD-grafts for outside-Milan candidates was associated with increased recurrence (P=0.039) and reduced survival (P=0.033).

CONCLUSION

This large two-center analysis confirms favorable outcomes after LT for HCC. Tumor size and number, pre-transplant AFP, and Milan criteria remain important recipient HCC-risk factors. A higher donor risk (i.e., donor age, DCD-grafts, ischemia time) was associated with poorer outcomes.

Deep learning-based phenotyping reclassifies combined hepatocellular-cholangiocarcinoma

Primary liver cancer arises either from hepatocytic or biliary lineage cells, giving rise to hepatocellular carcinoma (HCC) or intrahepatic cholangiocarcinoma (ICCA). Combined hepatocellular- cholangiocarcinomas (cHCC-CCA) exhibit equivocal or mixed features of both, causing diagnostic uncertainty and difficulty in determining proper management. Here, we perform a comprehensive deep learning-based phenotyping of multiple cohorts of patients. We show that deep learning can reproduce the diagnosis of HCC vs. CCA with a high performance. We analyze a series of 405 cHCC-CCA patients and demonstrate that the model can reclassify the tumors as HCC or ICCA, and that the predictions are consistent with clinical outcomes, genetic alterations and in situ spatial gene expression profiling. This type of approach could improve treatment decisions and ultimately clinical outcome for patients with rare and biphenotypic cancers such as cHCC-CCA.

Combined Liver Transplant and Cardiac Surgery: Long-Term Outcomes and Predictors of Success

OBJECTIVE

We aim to report our institutional outcomes of single-staged combined liver transplantation (LT) and cardiac surgery (CS).

SUMMARY BACKGROUND DATA

Concurrent LT and CS is a potential treatment for combined cardiac dysfunction and end-stage liver disease, yet only 54 cases have been previously reported in the literature. Thus, the outcomes of this approach are relatively unknown, and this approach has been previously regarded as extremely risky.

METHODS

Thirty-one patients at our institution underwent combined cardiac surgery and liver transplant. Patients with at least one-year follow-up were included. The Leave-One-Out Cross-Validation (LOOCV) machine-learning approach was used to generate a model for mortality.

RESULTS

Median follow-up was 8.2 years (IQR 4.6-13.6 y). One- and five-year survival was 74.2% (N=23) and 55% (N=17), respectively. Negative predictive factors of survival included recipient age>60 years (P=0.036), NASH-cirrhosis (P=0.031), Coronary Artery Bypass-Graft (CABG)-based CS (P=0.046) and pre-operative renal dysfunction (P=0.024). The final model demonstrated that renal dysfunction had a relative weighted impact of 3.2 versus CABG (1.7), age ≥60y (1.7) or NASH (1.3). Elevated LT+CS risk score was associated with an increased five-year mortality after surgery (AUC=0.731, P=<0.001). Conversely, the widely accepted STS-PROM calculator was unable to successfully stratify patients according to 1- (P>0.99) or 5-year (P=0.695) survival rates.

CONCLUSIONS

This is the largest series describing combined LT+CS, with joint surgical management appearing feasible in highly selected patients. CABG and pre-operative renal dysfunction are important negative predictors of mortality. The four-variable LT+CS score may help predict patients at high risk for post-operative mortality.

An attempt to establish and apply global benchmarks for liver resection of malignant hepatic tumors

BACKGROUND

Benchmarking is a process of continuous self-evaluation and comparison with best-in-class hospitals to guide quality improvement initiatives. We sought to define global benchmarks relative to liver resection for malignancy and to assess their achievement in hospitals in the United States.

METHODS

Patients who underwent curative-intent liver resection for hepatocellular carcinoma, intrahepatic cholangiocarcinoma, or colorectal or neuroendocrine liver metastases between 2000 and 2019 were identified from an international multi-institutional database. Propensity score matching was conducted to balance baseline characteristics between open and minimally invasive approaches. Best-in-class hospitals were defined relative to the achievement rate of textbook oncologic outcomes and case volume. Benchmark values were established relative to best-in-class institutions. The achievement of benchmark values among hospitals in the National Cancer Database was then assessed.

RESULTS

Among 2,624 patients treated at 20 centers, a majority underwent liver resection for hepatocellular carcinoma (n = 1,609, 61.3%), followed by colorectal liver metastases (n = 650, 24.8%), intrahepatic cholangiocarcinoma (n = 299, 11.4%), and neuroendocrine liver metastases (n = 66, 2.5%). Notably, 1,947 (74.2%) patients achieved a textbook oncologic outcome. After propensity score matching, 6 best-in-class hospitals with the highest textbook oncologic outcome rates (≥75.0%) were identified. Benchmark values were calculated for margin positivity (≤11.7%), 30-day readmission (≤4.1%), 30-day mortality (≤1.6%), minor postoperative complications (≤24.7%), severe complications (≤12.4%), and failure to achieve the textbook oncologic outcome (≤22.8%). Among the National Cancer Database hospitals, global benchmarks for margin positivity, 30-day readmission, 30-day mortality, severe complications, and textbook oncologic outcome failure were achieved in 62.9%, 27.1%, 12.1%, 7.1%, and 29.3% of centers, respectively.

CONCLUSION

These global benchmarks may help identify hospitals that may benefit from quality improvement initiatives, aiming to improve patient safety and surgical oncologic outcomes.

Comparing Outcomes of Minimally Invasive and Open Hepatectomy for Primary Liver Malignancies in Patients with Low-MELD Cirrhosis

INTRODUCTION

Cirrhotic patients with primary liver cancer may undergo curative-intent resection when selected appropriately. Patients with T1 tumors and low-MELD are generally referred for resection. We aim to evaluate whether minimally invasive hepatectomy (MIH) is associated with improved outcomes versus open hepatectomy (OH).

METHODS

NSQIP hepatectomy database 2014-2021 was used to select patients with T1 Hepatocellular Carcinoma (HCC) or Intra-hepatic Cholangiocarcionoma (IHCC) and low-MELD cirrhosis (MELD ≤ 10) who underwent partial hepatectomy. Propensity score matching was applied between OH and MIH patients, and 30-day postoperative outcomes were compared. Multivariable regression was used to identify predictors of post-hepatectomy liver failure (PHLF) in the selected population.

RESULTS

There were 922 patients: 494 (53.6%) OH, 372 (40.3%) MIH, and 56 (6.1%) began MIH converted to OH (analyzed with the OH cohort). We matched 354 pairs of patients with an adequate balance between the groups. MIH was associated with lower rates of bile leak (HR 0.37 [0.19-0.72)], PHLF (HR 0.36 [0.15-0.86]), collections requiring drainage (HR 0.30 [0.15-0.63]), postoperative transfusion (HR 0.36 [0.21-0.61]), major (HR 0.45 [0.27-0.77]), and overall morbidity (HR 0.44 [0.31-0.63]), and a two-day shorter median hospitalization (3 vs. 5 days; HR 0.61 [0.45-0.82]). No difference was noted in operative time, wound, respiratory, and septic complications, or mortality. Regression analysis identified ascites, prior portal vein embolization (PVE), additional hepatectomies, Pringle's maneuver, and OH (vs. MIH) as independent predictors of PHLF.

CONCLUSION

MIH for early-stage HCC/IHCC in low-MELD cirrhotic patients was associated with improved postoperative outcomes over OH. These findings suggest that MIH should be considered an acceptable approach in this population of patients.

The High Incidence of Occult Carcinoma in Total Hepatectomy Specimens of Patients Treated for Unresectable Colorectal Liver Metastases With Liver Transplant

OBJECTIVE

To describe the rate of occult carcinoma deposits in total hepatectomy specimens from patients treated with liver transplant (LT) for colorectal liver metastases (CRLM).

BACKGROUND

Previous studies have shown that patients with CRLM treated with systemic therapy demonstrate a high rate of complete radiographic response or may have disappearing liver metastases. However, this does not necessarily translate into a complete pathologic response, and residual invasive cancer may be found in up to 80% of the disappearing tumors after resection.

METHODS

Retrospective review of 14 patients who underwent LT for CRLM, at 2 centers. Radiographic and pathologic correlation of the number of tumors and their viability before and after LT was performed.

RESULTS

The median (interquartile range) number of tumors at diagnosis was 11 (4-23). The median number of chemotherapy cycles was 24 (16-37). Hepatic artery infusion was used in 5 patients (35.7%); 6 (42.9%) underwent surgical resection, and 5 (35.7%) received locoregional therapy. The indication for LT was unresectability in 8 patients (57.1%) and liver failure secondary to oncologic treatment in the remaining 6 (42.9%). Before LT, 7 patients (50%) demonstrated fluorodeoxyglucose-avid tumors and 7 (50%) had a complete radiographic response. Histopathologically, 11 patients (78.6%) had a viable tumor. Nine (64.2%) of the 14 patients were found to have undiagnosed metastases on explant pathology, with at least 22 unaccounted viable tumors before LT. Furthermore, 4 (57.1%) of the 7 patients who demonstrated complete radiographic response harbored viable carcinoma on explant pathology.

CONCLUSIONS

A complete radiographic response does not reliably predict a complete pathologic response. In patients with unresectable CRLM, total hepatectomy and LT represent a promising treatment options to prevent indolent disease progression from disappearing CRLM.

Immunotherapy Plus Locoregional Therapy Leading to Curative-Intent Hepatectomy in HCC: Proof of Concept Producing Durable Survival Benefits Detectable with Liquid Biopsy

BACKGROUND

Immunotherapy has emerged as an improved systemic treatment for select patients with advanced unresectable HCC. Objective response is reported in 30% of patients, yet complete response (pCR) allowing for curative-intent resection is rare. Locoregional therapies (LRTs) seem to show synergistic effects with immunotherapy, though this effect has not been scientifically reported. We report a cohort of patients showing pCR to immunotherapy + LRT as a proof of concept for the proposed treatment approach for locally unresectable HCC.

METHODS

Patients with unresectable HCC treated with immunotherapy as an intended destination therapy from 2016 to 2023 were included. The electronic health record was queried for oncologic information, locoregional therapies, surgical interventions, and long-term outcomes. Circulating tumor DNA (ctDNA) testing was obtained using Guardant360, and tumor mutational burden (TMB) was defined as the number of somatic mutations per megabase.

RESULTS

Ninety-six patients with advanced HCC received immunotherapy + LRT as a destination therapy. In total, 11 of 96 patients showed a complete response according to mRECIST criteria. Four of these (36.4%) ultimately underwent curative-intent resection. The median follow-up was 24.9 (IQR 15.6-38.3) months. Overall survival rates in those with complete response at 1, 3, and 5 years were 100%, 91%, and 81.8%, respectively, which were significantly improved compared to those of the cohort not achieving pCR (p < 0.001). All four patients undergoing immunotherapy + LRT followed by curative-intent hepatectomy have no evidence of disease (NED). Of those undergoing surgery, ctDNA was cleared in 75% (n = 3), providing an additional objective measurement of complete response. All four patients were TMB+ before beginning this treatment course, with three being TMB-, indicating stable and complete disease response.

CONCLUSIONS

Immunotherapy + locoregional therapy can help downstage a significant proportion of patients with initially unresectable HCC, allowing for curative-intent surgery. The survival benefit associated with complete response seems durable up to 3 years after achieving this response. ctDNA measurement was converted from positive to negative in this cohort, providing additional indication of response.

Using the win ratio to compare laparoscopic versus open liver resection for colorectal cancer liver metastases

Background

We sought to assess the overall benefit of laparoscopic versus open hepatectomy for treatment of colorectal liver metastases (CRLMs) using the win ratio, a novel methodological approach.

Methods

CRLM patients undergoing curative-intent resection in 2001-2018 were identified from an international multi-institutional database. Patients were paired and matched based on age, number and size of lesions, lymph node status and receipt of preoperative chemotherapy. The win ratio was calculated based on margin status, severity of postoperative complications, 90-day mortality, time to recurrence, and time to death.

Results

Among 962 patients, the majority underwent open hepatectomy (n=832, 86.5%), while a minority underwent laparoscopic hepatectomy (n=130, 13.5%). Among matched patient-to-patient pairs, the odds of the patient undergoing laparoscopic resection "winning" were 1.77 [WR: 1.77, 95% confidence interval (CI): 1.42-2.34]. The win ratio favored laparoscopic hepatectomy independent of low (WR: 2.94, 95% CI: 1.20-6.39), medium (WR: 1.56, 95% CI: 1.16-2.10) or high (WR: 7.25, 95% CI: 1.13-32.0) tumor burden, as well as unilobar (WR: 1.71, 95% CI: 1.25-2.31) or bilobar (WR: 4.57, 95% CI: 2.36-8.64) disease. The odds of "winning" were particularly pronounced relative to short-term outcomes (i.e., 90-day mortality and severity of postoperative complications) (WR: 4.06, 95% CI: 2.33-7.78).

Conclusions

Patients undergoing laparoscopic hepatectomy had 77% increased odds of "winning". Laparoscopic liver resection should be strongly considered as a preferred approach to resection in CRLM patients.

Immunotherapy for Advanced Hepatocellular Carcinoma-a Large Tertiary Center Experience

INTRODUCTION

Combination of immune-checkpoint inhibitor (ICI) and vascular endothelial growth factor (VEGF) antagonist has become the first line systemic treatment for advanced hepatocellular carcinoma (HCC). However, two-thirds of patients do not respond to ICI-based treatments and biomarkers for response remain elusive.

METHODS

Patients with advanced HCC who received Atezolizumab/Bevacizumab combination or Nivolumab during 2016-2022 were identified in our Liver Cancer Database. Retrospective review of their clinical data was performed to investigate parameters that could be predictive of immunotherapy response.

RESULTS

96 patients received Atezolizumab/Bevacizumab (n=60) or Nivolumab (n=36). Median age at diagnosis was 67.1 years. 70 patients had received treatment and 26 patients were treatment naïve before starting immunotherapy. Mean pre-treatment AFP was 9780.7 (±32035) ng/mL. Confirmed objective response (complete or partial) was seen in 29% of the population (n=27). Disease remained stable in 12% (n=11) and progressed in 60% (n=56). On univariate analysis, pre-treatment AFP>400 ng/mL was associated with objective response (OR=4.5, 95% CI:1.7-11.9, p=0.0015), while white race (OR=0.35, 95% CI:0.13-0.92, p=0.030) and prior radiotherapy (OR=0.14, 95% CI:0.01-1.1, p=0.033) or systemic therapy with TKIs (OR=0.25, 95% CI:0.08-0.81, p=0.017) were associated with poor response. On multivariate analysis only AFP>400 ng/mL remained associated with response (OR=3.7, 95% CI:1.3-10.5, p=0.014). Overall survival (OS) at one and three years was 86% and 43% in responders, and 45% and 29% in non-responders, respectively.

CONCLUSION

In our institutional experience, treatment naivety and pre-treatment AFP>400 ng/mL were associated with objective response. Prospective studies aimed at identifying factors associated with response to immunotherapy will aide patient selection.

Characterization of Salivary and Plasma Metabolites as Biomarkers for HCC: A Pilot Study

(1) Background: The incidence of hepatocellular carcinoma (HCC) is rising, and current screening methods lack sensitivity. This study aimed to identify distinct and overlapping metabolites in saliva and plasma that are significantly associated with HCC. (2) Methods: Saliva samples were collected from 42 individuals (HCC = 16, cirrhosis = 12, healthy = 14), with plasma samples from 22 (HCC = 14, cirrhosis = 2, healthy = 6). We performed untargeted mass spectrometry on blood and plasma, tested metabolites for associations with HCC or cirrhosis using a logistic regression, and identified enriched pathways with Metaboanalyst. Pearson's correlation was employed to test for correlations between salivary and plasma metabolites. (3) Results: Six salivary metabolites (1-hexadecanol, isooctanol, malonic acid, N-acetyl-valine, octadecanol, and succinic acid) and ten plasma metabolites (glycine, 3-(4-hydroxyphenyl)propionic acid, aconitic acid, isocitric acid, tagatose, cellobiose, fucose, glyceric acid, isocitric acid, isothreonic acid, and phenylacetic acid) were associated with HCC. Malonic acid was correlated between the paired saliva and plasma samples. Pathway analysis highlighted deregulation of the 'The Citric Acid Cycle' in both biospecimens. (4) Conclusions: Our study suggests that salivary and plasma metabolites may serve as independent sources for HCC detection. Despite the lack of correlation between individual metabolites, they converge on 'The Citric Acid Cycle' pathway, implicated in HCC pathogenesis.

The impact of recurrence timing and tumor burden score on overall survival among patients undergoing repeat hepatectomy for colorectal liver metastases

INTRODUCTION

Approximately 15% of patients experience a resectable intrahepatic recurrence after an index curative-intent hepatectomy for colorectal liver metastases (CRLM). We sought to investigate the impact of recurrence timing and tumor burden score (TBS) at the time of recurrence on overall survival among patients undergoing repeat hepatectomy.

METHODS

Patients with CRLM who experienced recurrent intrahepatic disease after initial hepatectomy between 2000 and 2020 were identified from an international multi-institutional database. The impact of time-TBS, defined as TBS divided by the time interval of recurrence, was assessed relative to overall survival.

RESULTS

Among 220 patients, the median age was 60.9 years (interquartile range [IQR]: 53.0-69.0), and 144 (65.5%) patients were male. Most patients experienced multiple recurrences (n = 120, 54.5%) within 12 months after the initial hepatectomy (n = 139, 63.2%). The median tumor size of the recurrent CRLM was 2.2 cm (IQR: 1.5-3.0 cm) with a median TBS of 3.5 (2.3-4.9) at the time of recurrence. Overall, 121 (55.0%) patients underwent repeat hepatectomy, whereas 99 (45.0%) individuals were treated with systemic chemotherapy or other nonsurgical treatments; repeat hepatectomy was associated with better postrecurrence survival (PRS) (p < 0.001). Three-year PRS incrementally worsened (low time-TBS: 71.7%, 95% confidence interval [CI], 57.9-88.8 vs. medium: 63.6%, 95% CI, 47.7-84.8 vs. high: 49.2%, 95% CI, 31.1-77.7, p = 0.02) as time-TBS values increased. Each unit increase in time-TBS score was independently associated with a 41% higher possibility of death (hazard ratio: 1.41; 95% CI, 1.04-1.90, p = 0.03).

CONCLUSIONS

Time-TBS was associated with long-term outcomes after repeat hepatectomy for recurrent CRLM. Time-TBS may be an easy tool to help select patients who may benefit the most from repeat hepatic resection of recurrent CRLM.

Circulating Tumor DNA in Colorectal Cancer Liver Metastasis: Analysis of Patients Receiving Liver Resection and Transplant

PURPOSE

Liver metastases occur in about 50% of colorectal cancer cases and drive patient outcomes. Circulating tumor DNA (ctDNA) is emerging as a diagnostic, surveillance, and tumor mutational information tool.

METHODS

Patients with colorectal cancer liver metastasis (CCLM) seen in a multidisciplinary liver tumor clinic from January to August 2022 received ctDNA testing on each visit. ctDNA was obtained using the Guardant360 platform. Tumor mutational burden (TMB) is defined as the number of identified mutations per megabase of genome analyzed.

RESULTS

Fifty-two patients had available ctDNA, with 34 (65%) tested preoperatively and 18 (35%) postoperatively; nine patients had sequential pre- and postoperative testing. The median time to test result was 12 days (IQR, 10-13.5). There were a greater number of somatic mutations identified preoperatively (n = 29 v n = 11) and a greater genomic heterogeneity (P = .0069). The mean TMB score was 12.77 in those without pathologic response to cytotoxic therapy and 6.0 in those with pathologic response (P = .10). All nine patients with sequential testing were positive preoperatively, compared with just three (33.3%) postoperatively (P = .0090). Positive postoperative ctDNA was associated with the increased likelihood of disease recurrence after resection (57%) versus negative ctDNA (0%, P = .0419).

CONCLUSION

Routine ctDNA screening in patients with CCLM is logistically feasible. Liver resection and/or transplant may be associated with clearance of detectable ctDNA and a reduction in TMB or genomic heterogeneity. Persistence of ctDNA alterations postresection appears predictive of disease recurrence. Further studies are necessary to confirm these findings, and longitudinal ctDNA testing is needed to monitor changing tumor biology.

Development and validation of a REcurrent Liver cAncer Prediction ScorE (RELAPSE) following liver transplantation in patients with hepatocellular carcinoma: Analysis of the US Multicenter HCC Transplant Consortium

HCC recurrence following liver transplantation (LT) is highly morbid and occurs despite strict patient selection criteria. Individualized prediction of post-LT HCC recurrence risk remains an important need. Clinico-radiologic and pathologic data of 4981 patients with HCC undergoing LT from the US Multicenter HCC Transplant Consortium (UMHTC) were analyzed to develop a REcurrent Liver cAncer Prediction ScorE (RELAPSE). Multivariable Fine and Gray competing risk analysis and machine learning algorithms (Random Survival Forest and Classification and Regression Tree models) identified variables to model HCC recurrence. RELAPSE was externally validated in 1160 HCC LT recipients from the European Hepatocellular Cancer Liver Transplant study group. Of 4981 UMHTC patients with HCC undergoing LT, 71.9% were within Milan criteria, 16.1% were initially beyond Milan criteria with 9.4% downstaged before LT, and 12.0% had incidental HCC on explant pathology. Overall and recurrence-free survival at 1, 3, and 5 years was 89.7%, 78.6%, and 69.8% and 86.8%, 74.9%, and 66.7%, respectively, with a 5-year incidence of HCC recurrence of 12.5% (median 16 months) and non-HCC mortality of 20.8%. A multivariable model identified maximum alpha-fetoprotein (HR = 1.35 per-log SD, 95% CI,1.22-1.50, p < 0.001), neutrophil-lymphocyte ratio (HR = 1.16 per-log SD, 95% CI,1.04-1.28, p < 0.006), pathologic maximum tumor diameter (HR = 1.53 per-log SD, 95% CI, 1.35-1.73, p < 0.001), microvascular (HR = 2.37, 95%-CI, 1.87-2.99, p < 0.001) and macrovascular (HR = 3.38, 95% CI, 2.41-4.75, p < 0.001) invasion, and tumor differentiation (moderate HR = 1.75, 95% CI, 1.29-2.37, p < 0.001; poor HR = 2.62, 95% CI, 1.54-3.32, p < 0.001) as independent variables predicting post-LT HCC recurrence (C-statistic = 0.78). Machine learning algorithms incorporating additional covariates improved prediction of recurrence (Random Survival Forest C-statistic = 0.81). Despite significant differences in European Hepatocellular Cancer Liver Transplant recipient radiologic, treatment, and pathologic characteristics, external validation of RELAPSE demonstrated consistent 2- and 5-year recurrence risk discrimination (AUCs 0.77 and 0.75, respectively). We developed and externally validated a RELAPSE score that accurately discriminates post-LT HCC recurrence risk and may allow for individualized post-LT surveillance, immunosuppression modification, and selection of high-risk patients for adjuvant therapies.

Simultaneous versus staged resection for synchronous colorectal liver metastases: The win ratio approach

INTRODUCTION

In order to investigate the optimal approach for synchronous colorectal liver metastases (sCRLM), we sought to use the "win ratio" (WR), a novel statistical approach, to assess the relative benefit of simultaneous versus staged surgical treatment.

METHODS

Patients who underwent hepatectomy for sCRLM between 2008 and 2020 were identified from a multi-institutional database. The WR approach was utilized to compare composite outcomes of patients undergoing simultaneous versus staged resection.

RESULTS

Among 1116 patients, 642 (57.5%) presented with sCRLM; 290 (45.2%) underwent simultaneous resection, while 352 (54.8%) underwent staged resection. In assessing the composite outcome, staged resection yielded a WR of 1.59 (95%CI 1.47-1.71) over the simultaneous approach for sCRLM. The highest WR occurred among patients requiring major hepatectomy (WR = 1.93, 95%CI 1.77-2.10) compared with patients who required minor liver resection (WR = 1.55, 95%CI 1.44-1.70).

CONCLUSIONS

Staged resection was superior to simultaneous resection for sCRLM based on a WR assessment.

Proximal Splenic Artery Embolization for Refractory Ascites and Hydrothorax Post-Liver Transplant

PURPOSE

Proximal splenic artery embolization (pSAE) has been advocated as a valuable tool to ameliorate portal hyper-perfusion (PHP). The purpose of this study was to determine the safety and efficacy of pSAE to treat refractory ascites (RA) and/or refractory hydrothorax (RH) in the setting of PHP post-liver transplant.

MATERIAL AND METHODS

A total of 30 patients who underwent pSAE for RA and/or RH after liver transplantation (LT) between January 2007 and December 2017 were analyzed retrospectively. The patients were divided into groups according to the time frame from pSAE to clinical resolution in order to identify predictors of RA/RH response to the procedure.

RESULTS

Twenty-four (80%) patients responded to pSAE within three months, whereas 6 (20%) still required additional treatments for RA/RH at three months post-pSAE. In all cases clinical symptoms resolved within six months. Complications after pSAE were as follows: 2 cases of splenic infarction (6.6%), one case of post-splenic embolization syndrome (3.3%), one case of hepatic artery thrombosis (3.3%) and one case of portal vein (PV) thrombosis (3.3%). Increased intraoperative PV flow volume and increased pre-pSAE PV velocity, as well as higher estimated glomerular filtration rate were associated with early RA/RH resolution.

CONCLUSION

pSAE is safe and effective in treating RA and RH due to PHP after LT. This study suggests that clinical parameters indicating more severe PHP and better kidney function are possible predictors for early response to pSAE.

Metabolomic differences in young-onset versus average-onset colorectal adenocarcinoma

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Background: Novel deleterious effects of environmental exposures may play a role in the rising incidence of young-onset colorectal cancer (yoCRC). We used metabolomics to assess differences between yoCRC and average-onset CRC (aoCRC), in comparison to healthy controls, which may suggest certain exposure risks. Methods: Patients with stage I-IV CRC and healthy controls were identified from prospective biobanks and categorized based on age<50 years (yoCRC or young controls) or age>60 years (aoCRC or older controls). Serum metabolites were profiled using GC-TOF mass spectrometry. Differential abundance of metabolites was investigated using unadjusted logistic regression. Metabolic pathway analysis was performed using Metaboanalyst 5.0. All p-values were adjusted for multiple testing (false-discovery rate, FDR p<0.20 considered significant). Results: The study population comprised 170 CRC patients (66 yoCRC and 104 aoCRC) and 49 healthy controls (34 young and 15 old). Association analyses revealed four differentially abundant metabolites: citrate (FDR p=0.04), cholesterol (0.14), and two unidentified metabolites (UM). Metabolic pathways significantly altered in yoCRC vs. aoCRC included: carbohydrate metabolism (citrate cycle, FDR p=0.11), carbohydrate biosynthesis (glyoxylate and dicarboxylate metabolism, FDR p=0.03), amino-acid metabolism (alanine, aspartate, and glutamate metabolism, FDR p=0.04, arginine biosynthesis, FDR p=0.04, and amino-acid t-RNA biosynthesis, FDR p=0.04). There were no significant metabolomic differences between young and older controls. Conclusions: We identified significant differences in the citrate cycle - a core pathway of cellular metabolism and associated with colorectal cancer. Metabolomic differences in pathways of carcinogenic significance (aspartate) and environmental exposures (arginine and dietary red meat) were also noted, suggesting potential relationships with younger age of CRC onset. The study provides future directions for more precise analyses with a larger sample size for healthy controls and adjusting for confounders. [Table: see text]

Living Donor Liver Transplantation With Augmented Venous Outflow and Splenectomy: A Promised Land for Small Left Lobe Grafts

OBJECTIVE

Living donor liver transplantation (LDLT) using small grafts, especially left lobe grafts (H1234-MHV) (LLG), continues to be a challenge due to small-for-size syndrome (SFSS). We herein demonstrate that with surgical modifications, outcomes with small grafts can be improved.

METHODS

Between 2012 and 2020, we performed 130 adult LDLT using 61 (47%) LLG (H1234-MHV) in a single Enterprise. The median graft-to-recipient weight ratio was 0.84%, with graft-to-recipient weight ratio <0.7% accounting for 22%. Splenectomy was performed in 72 (56%) patients for inflow modulation before (n=50) or after (n=22) graft reperfusion. In LLG-LDLT, venous outflow was achieved using all three recipient hepatic veins. In right lobe graft (H5678) (RLG)-LDLT, the augmented graft right hepatic vein was anastomosed to the recipient's cava with a large cavotomy. Outcome measures include SFSS, early allograft dysfunction (EAD), and survival.

RESULTS

Graft survival rates at 1, 3, and 5 years were 94%, 90%, and 83%, respectively, with no differences between LLG (H1234-MHV) and RLG (H5678). Splenectomy significantly reduced portal flow without increasing the complication rate. Despite the aggressive use of small grafts, SFSS and EAD developed in only 1 (0.8%) and 18 (13.8%) patients, respectively. Multivariable logistic regression revealed model for end-stage liver disease score and LLG (H1234-MHV) as independent risk factors for EAD and splenectomy as a protective factor (odds ratio: 0.09; P =0.03). For LLG (H1234-MHV)-LDLT, patients who underwent prereperfusion splenectomy tended to have better 1-year graft survival than those receiving postreperfusion splenectomy.

CONCLUSIONS

LLG (H1234-MHV) are feasible in adult LDLT with excellent outcomes comparable to RLG (H5678). Venous outflow augmentation and splenectomy help lower the threshold of using small-for-size grafts without compromising graft survival.

Machine Learning Approach to Stratifying Prognosis Relative to Tumor Burden after Resection of Colorectal Liver Metastases: An International Cohort Analysis

BACKGROUND

Assessing overall tumor burden on the basis of tumor number and size may assist in prognostic stratification of patients after resection of colorectal liver metastases (CRLM). We sought to define the prognostic accuracy of tumor burden by using machine learning (ML) algorithms compared with other commonly used prognostic scoring systems.

STUDY DESIGN

Patients who underwent hepatectomy for CRLM between 2001 and 2018 were identified from a multi-institutional database and split into training and validation cohorts. ML was used to define tumor burden (ML-TB) based on CRLM tumor number and size thresholds associated with 5-year overall survival. Prognostic ability of ML-TB was compared with the Fong and Genetic and Morphological Evaluation scores using Cohen's d.

RESULTS

Among 1,344 patients who underwent resection of CRLM, median tumor number (2, interquartile range 1 to 3) and size (3 cm, interquartile range 2.0 to 5.0) were comparable in the training (n = 672) vs validation (n = 672) cohorts; patient age (training 60.8 vs validation 61.0) and preoperative CEA (training 10.2 ng/mL vs validation 8.3 ng/mL) was also similar (p > 0.05). ML empirically derived optimal cutoff thresholds for number of lesions (3) and size of the largest lesion (1.3 cm) in the training cohort, which were then used to categorize patients in the validation cohort into 3 prognostic groups. Patients with low, average, or high ML-TB had markedly different 5-year overall survival (51.6%, 40.9%, and 23.1%, respectively; p < 0.001). ML-TB was more effective at stratifying patients relative to 5-year overall survival (low vs high ML-TB, d = 2.73) vs the Fong clinical (d = 1.61) or Genetic and Morphological Evaluation (d = 0.84) scores.

CONCLUSIONS

Using a large international cohort, ML was able to stratify patients into 3 distinct prognostic categories based on overall tumor burden. ML-TB was noted to be superior to other CRLM prognostic scoring systems.

Recipient and Donor Outcomes After Living-Donor Liver Transplant for Unresectable Colorectal Liver Metastases

Question

What are the estimated overall and recurrence-free survival outcomes after living-donor liver transplant (LDLT) in patients with liver-confined, unresectable colorectal cancer liver metastasis (CRLM)?

Findings

In this cohort study of 10 adults with CRLM who received LDLT, Kaplan-Meier estimates of recurrence-free and overall survival at a median follow-up of 1.5 years were 62% and 100%, respectively. Perioperative outcomes for both recipients and donors were consistent with established benchmarks.

Meaning

The results suggest that LDLT may be a viable treatment option for select patients with unresectable CRLMs with favorable tumor biology.

Importance

Colorectal cancer is a leading cause of cancer-related death, and nearly 70% of patients with this cancer have unresectable colorectal cancer liver metastases (CRLMs). Compared with chemotherapy, liver transplant has been reported to improve survival in patients with CRLMs, but in North America, liver allograft shortages make the use of deceased-donor allografts for this indication problematic.

Objective

To examine survival outcomes of living-donor liver transplant (LDLT) for unresectable, liver-confined CRLMs.

Design, Setting, and Participants

This prospective cohort study included patients at 3 North American liver transplant centers with established LDLT programs, 2 in the US and 1 in Canada. Patients with liver-confined, unresectable CRLMs who had demonstrated sustained disease control on oncologic therapy met the inclusion criteria for LDLT. Patients included in this study underwent an LDLT between July 2017 and October 2020 and were followed up until May 1, 2021.

Exposures

Living-donor liver transplant.

Main Outcomes and Measures

Perioperative morbidity and mortality of treated patients and donors, assessed by univariate statistics, and 1.5-year Kaplan-Meier estimates of recurrence-free and overall survival for transplant recipients.

Results

Of 91 evaluated patients, 10 (11%) underwent LDLT (6 [60%] male; median age, 45 years [range, 35-58 years]). Among the 10 living donors, 7 (70%) were male, and the median age was 40.5 years (range, 27-50 years). Kaplan-Meier estimates for recurrence-free and overall survival at 1.5 years after LDLT were 62% and 100%, respectively. Perioperative morbidity for both donors and recipients was consistent with established standards (Clavien-Dindo complications among recipients: 3 [10%] had none, 3 [30%] had grade II, and 4 [40%] had grade III; donors: 5 [50%] had none, 4 [40%] had grade I, and 1 had grade III).

Conclusions and Relevance

This study’s findings of recurrence-free and overall survival rates suggest that select patients with unresectable, liver-confined CRLMs may benefit from total hepatectomy and LDLT.

Nontumor related risk score: A new tool to improve prediction of prognosis after hepatectomy for colorectal liver metastases

BACKGROUND

Prognostic stratification of patients with colorectal cancer liver metastasis based solely on tumor-related factors has only moderate discriminatory ability. We hypothesized that the inclusion of nontumor related factors can improve prediction of long-term prognosis of patients with colorectal cancer liver metastasis.

METHODS

Nontumor related laboratory markers were assessed utilizing a training cohort from 2 U.S. institutions (n = 1,205). Factors independently associated with prognosis were used to develop a nontumor related prognostic score. The discriminatory ability, assessed by Harrell's C-statistics (C-index) and net reclassification improvement, was validated and compared with 3 commonly used tumor-related clinical risk scores: Fong clinical risk scores, m-clinical risk scores, and Genetic and Morphological Evaluation (GAME) score in an external validation cohort from 5 Asian (n = 1,307) and 3 European (n = 1,058) institutions. The discriminatory ability of nontumor related prognostic score combined with each of these 3 tumor-related prognostic scores was also estimated.

RESULTS

Alkaline phosphatase (hazard ratio 1.43; 95% confidence interval, 1.11-1.84), albumin (hazard ratio 0.71; 95% confidence interval, 0.57-0.89), and mean corpuscular volume (hazard ratio 19.0, per log unit; 95% confidence interval, 4.79-75.0) were each independently associated with increased risk of death after resection of colorectal cancer liver metastasis (all P < .05). In turn, alkaline phosphatase, albumin, and mean corpuscular volume were combined to form a nontumor related prognostic score (2.942 × mean corpuscular volume + 0.399 × alkaline phosphatase-0.339 × albumin-12) × 10 (median, 16; range, 1-30). The nontumor related prognostic score had good-to-modest discriminatory ability in the external cohort (C-index = 0.58), which was comparable to the 3 established tumor-related prognostic scores (C-index: Fong clinical risk scores, 0.53, m-clinical risk scores, 0.55, GAME, 0.58). The addition of the nontumor related prognostic score to the tumor-related prognostic scores enhanced the discriminatory ability in the entire study cohort (C-index: nontumor related score+Fong, 0.60, nontumor related score+m-clinical risk scores, 0.61, nontumor related score+GAME, 0.64), as well reclassification improvement (42.5, 42.7%, and 21.2%, respectively).

CONCLUSION

Nontumor related prognostic information may help improve the prognostic stratification of patients after resection of colorectal cancer liver metastasis. The nontumor related prognostic score may be combined with tumor-related prognostic tools to enhance prognostic stratification of patients with colorectal cancer liver metastasis.

Transplantation of declined livers after normothermic perfusion

BACKGROUND

The persistent shortage of liver allografts contributes to significant waitlist mortality despite efforts to increase organ donation. Normothermic machine perfusion holds the potential to enhance graft preservation, extend viability, and allow liver function evaluation in organs previously discarded because considered too high-risk for transplant.

METHODS

Discarded livers from other transplant centers were transplanted after assessment and reconditioning with our institutionally developed normothermic machine perfusion device. We report here our preliminary data.

RESULTS

Twenty-one human livers declined for transplantation were enrolled for assessment with normothermic machine perfusion. Six livers (28.5%) were ultimately discarded after normothermic machine perfusion because of insufficient lactate clearance (>4.1 mmol/L after 4 hours), limited bile production (<0.5 mI/h), or moderate macrosteatosis, whereas 15 (71.5%) were considered suitable for transplantation. Normothermic machine perfusion duration was from 3 hours, 49 minutes to 10 hours, 29 minutes without technical problems or adverse events. No intraoperative or major early postoperative complications occurred in all transplanted recipients. No primary nonfunction occurred after transplantation. Seven livers had early allograft dysfunction with fast recovery, and 1 patient developed ischemic cholangiopathy after 4 months treated with biliary stents. All other patients had good liver function with a follow-up time of 8 weeks to 14 months.

CONCLUSION

In total, 71.5% of discarded livers subjected to ex vivo normothermic machine perfusion were successfully transplanted after organ perfusion and assessment using an institutionally built device. This study challenges the current viability criteria reported in the literature and calls for a standardization of viability markers collection, an essential condition for the advancement of the field.

Salivary miRNAs as non-invasive biomarkers of hepatocellular carcinoma: a pilot study

BACKGROUND

Improved detection of hepatocellular carcinoma (HCC) is needed, as current detection methods, such as alpha fetoprotein (AFP) and ultrasound, suffer from poor sensitivity. MicroRNAs (miRNAs) are small, non-coding RNAs that regulate many cellular functions and impact cancer development and progression. Notably, miRNAs are detectable in saliva and have shown potential as non-invasive biomarkers for a number of cancers including breast, oral, and lung cancers. Here, we present, to our knowledge, the first report of salivary miRNAs in HCC and compare these findings to patients with cirrhosis, a high-risk cohort for HCC.

METHODS

We performed small RNA sequencing in 20 patients with HCC and 19 with cirrhosis. Eleven patients with HCC had chronic liver disease, and analyses were performed with these samples combined and stratified by the presence of chronic liver disease. P values were adjusted for multiple comparisons using a false discovery rate (FDR) approach and miRNA with FDR P < 0.05 were considered statistically significant. Differential expression of salivary miRNAs was compared to a previously published report of miRNAs in liver tissue of patients with HCC vs cirrhosis. Support vector machines and leave-one-out cross-validation were performed to determine if salivary miRNAs have predictive potential for detecting HCC.

RESULTS

A total of 4,565 precursor and mature miRNAs were detected in saliva and 365 were significantly different between those with HCC compared to cirrhosis (FDR P < 0.05). Interestingly, 283 of these miRNAs were significantly downregulated in patients with HCC. Machine-learning identified a combination of 10 miRNAs and covariates that accurately classified patients with HCC (AUC = 0.87). In addition, we identified three miRNAs that were differentially expressed in HCC saliva samples and in a previously published study of miRNAs in HCC tissue compared to cirrhotic liver tissue.

CONCLUSIONS

This study demonstrates, for the first time, that miRNAs relevant to HCC are detectable in saliva, that salivary miRNA signatures show potential to be highly sensitive and specific non-invasive biomarkers of HCC, and that additional studies utilizing larger cohorts are needed.

The Prognostic Utility of Intraoperative Allograft Vascular Inflow Measurements in Donation After Circulatory Death Liver Transplantation

Donation after circulatory death (DCD) liver transplantation improves deceased donor liver use and decreases waitlist burden, albeit at an increased risk of biliary complications and inferior graft survival. Employing liver vascular inflow measurements intraoperatively permits allograft prognostication. However, its use in DCD liver transplantation is hitherto largely unknown and further explored here. DCD liver transplantation patient records at a single center from 2005 to 2018 were retrospectively scrutinized. Intraoperative flow data and relevant donor parameters were analyzed against endpoints of biliary events and graft survival. A total of 138 cases were chosen. The incidence of cumulative biliary complications was 38%, the majority of which were anastomotic strictures and managed successfully by endoscopic means. The ischemic cholangiopathy rate was 6%. At median thresholds of a portal vein (PV) flow rate of <92 mL/minute/100 g and buffer capacity (BC) of >0.04, both variables were independently associated with risk of biliary events (P = 0.01 and 0.04, respectively). Graft survival was 90% at 12 months and 75% at 5 years. Cox regression analysis revealed a PV flow rate of <50 mL/minute/100 g as predictive of poorer graft survival (P = 0.01). Furthermore, 126 of these DCD livers were analyzed against a propensity-matched group of 378 contemporaneous donation after brain death liver allografts (1:3), revealing significantly higher rates (P < 0.001) of both early allograft dysfunction (70% versus 30%) and biliary complications (37% versus 20%) in the former group. Although flow data were comparable between both sets, PV flow and BC were predictive of biliary events only in the DCD cohort. Intraoperative inflow measurements therefore provide valuable prognostication on biliary/graft outcomes in DCD liver transplantation, can help inform graft surveillance, and its routine use is recommended.

Two pumps or one pump? A comparison of human liver normothermic machine perfusion devices for transplantation

BACKGROUND

Normothermic machine perfusion provides continuous perfusion to ex situ hepatic grafts through the portal vein and the hepatic artery. Because the portal vein has high flow with low pressure and the hepatic artery has low flow with high pressure, different types of perfusion machines have been employed to match the two vessels' infusion hemodynamics.

METHODS

We compared transplanted human livers perfused through a 2-pump (n = 9) versus a 1-pump perfusion system (n = 6) where a C-clamp is used as a tubing constrictor to regulate hemodynamics.

RESULTS

There was no significant difference between groups in portal vein or hepatic artery flow rate. The 1-pump group had more hemoglobin in the perfusate. However, there was no significant difference in plasma hemoglobin between the 2-pump and 1-pump groups at each time point or in the change in levels, proving no hemolysis occurred due to C-clamp tube constriction. After transplantation, the 2-pump group had two cases of early allograft dysfunction (EAD), whereas the 1-pump group had no EAD. There was no graft failure or patient death in either group during follow-up ranging from 20-52 months.

CONCLUSIONS

Our data show that the 1-pump design provided the same hemodynamic output as the 2-pump design, with no additional hemolytic risk, but with the benefits of lower costs, easier transport and faster and simpler setting.

The utility of laparoscopic ultrasound during minimally invasive liver procedures in patients with malignant liver tumors who have undergone preoperative magnetic resonance imaging

BACKGROUND

The aim of this study was to assess the utility of laparoscopic ultrasound (LUS) during minimally invasive liver procedures in patients with malignant liver tumors who underwent preoperative magnetic resonance imaging (MRI).

METHODS

Medical records of patients with malignant liver lesions who underwent laparoscopic liver surgery between October 2005 and January 2018 and who underwent an MRI examination at our institution within a month before surgery were collected from a prospectively maintained database. The size and location of tumors detected on LUS, as well as whether they were seen on preoperative imaging, were recorded. Univariate and multivariate regression analyses were performed to identify factors that were associated with the detection of liver lesions on LUS that were not seen on preoperative MRI.

RESULTS

A total of 467 lesions were identified in 147 patients. Tumor types included colorectal cancer metastasis (n = 53), hepatocellular cancer (n = 38), neuroendocrine metastasis (n = 23), and others (n = 33). Procedures included ablation (67%), resection (23%), combined resection and ablation (6%), and diagnostic laparoscopy with biopsy (4%). LUS identified 39 additional lesions (8.4%) that were not seen on preoperative MRI in 14 patients (10%). These were colorectal cancer (n = 20, 51%), neuroendocrine (n = 11, 28%) and other metastases (n = 8, 21%). These additional findings on LUS changed the treatment plan in 13 patients (8.8%). Factors predicting tumor detection on LUS but not on MRI included obesity (p = 0.02), previous exposure to chemotherapy (p < 0.001), and lesion size < 1 cm (p < 0.001).

CONCLUSION

This study demonstrates that, despite advances in MRI, LUS performed during minimally invasive liver procedures may detect additional tumors in 10% of patients with liver malignancies, with the highest yield seen in obese patients with previous exposure to chemotherapy. These results support the routine use of LUS by hepatic surgeons.

Optimal Timing of Administration of Direct-acting Antivirals for Patients With Hepatitis C-associated Hepatocellular Carcinoma Undergoing Liver Transplantation

OBJECTIVE

To investigate the optimal timing of direct acting antiviral (DAA) administration in patients with hepatitis C-associated hepatocellular carcinoma (HCC) undergoing liver transplantation (LT).

SUMMARY OF BACKGROUND DATA

In patients with hepatitis C (HCV) associated HCC undergoing LT, the optimal timing of direct-acting antivirals (DAA) administration to achieve sustained virologic response (SVR) and improved oncologic outcomes remains a topic of much debate.

METHODS

The United States HCC LT Consortium (2015-2019) was reviewed for patients with primary HCV-associated HCC who underwent LT and received DAA therapy at 20 institutions. Primary outcomes were SVR and HCC recurrence-free survival (RFS).

RESULTS

Of 857 patients, 725 were within Milan criteria. SVR was associated with improved 5-year RFS (92% vs 77%, P < 0.01). Patients who received DAAs pre-LT, 0-3 months post-LT, and ≥3 months post-LT had SVR rates of 91%, 92%, and 82%, and 5-year RFS of 93%, 94%, and 87%, respectively. Among 427 HCV treatment-naïve patients (no previous interferon therapy), patients who achieved SVR with DAAs had improved 5-year RFS (93% vs 76%, P < 0.01). Patients who received DAAs pre-LT, 0-3 months post-LT, and ≥3 months post-LT had SVR rates of 91%, 93%, and 78% (P < 0.01) and 5-year RFS of 93%, 100%, and 83% (P = 0.01).

CONCLUSIONS

The optimal timing of DAA therapy appears to be 0 to 3 months after LT for HCV-associated HCC, given increased rates of SVR and improved RFS. Delayed administration after transplant should be avoided. A prospective randomized controlled trial is warranted to validate these results.

Salivary Metabolites are Promising Non-Invasive Biomarkers of Hepatocellular Carcinoma and Chronic Liver Disease

Background

Hepatocellular carcinoma (HCC) is a leading causes of cancer mortality worldwide. Improved tools are needed for detecting HCC so that treatment can begin as early as possible. Current diagnostic approaches and existing biomarkers, such as alpha-fetoprotein (AFP) lack sensitivity, resulting in too many false negative diagnoses. Machine-learning may be able to identify combinations of biomarkers that provide more robust predictions and improve sensitivity for detecting HCC. We sought to evaluate whether metabolites in patient saliva could distinguish those with HCC, cirrhosis, and those with no documented liver disease.

Methods and Results

We tested 125 salivary metabolites from 110 individuals (43 healthy, 37 HCC, 30 cirrhosis) and identified 4 metabolites that displayed significantly different abundance between groups (FDR P <.2). We also developed four tree-based, machine-learning models, optimized to include different numbers of metabolites, that were trained using cross-validation on 99 patients and validated on a withheld test set of 11 patients. A model using 12 metabolites -octadecanol, acetophenone, lauric acid, 1-monopalmitin, dodecanol, salicylaldehyde, glycyl-proline, 1-monostearin, creatinine, glutamine, serine and 4-hydroxybutyric acid- had a cross-validated sensitivity of 84.8%, specificity of 92.4% and correctly classified 90% of the HCC patients in the test cohort. This model outperformed previously reported sensitivities and specificities for AFP (20-100ng/ml) (61%, 86%) and AFP plus ultrasound (62%, 88%).

Conclusions and Impact

Metabolites detectable in saliva may represent products of disease pathology or a breakdown in liver function. Notably, combinations of salivary metabolites derived from machine-learning may serve as promising non-invasive biomarkers for the detection of HCC.

Dynamic α-Fetoprotein Response and Outcomes After Liver Transplant for Hepatocellular Carcinoma

Importance

Accurate preoperative prediction of hepatocellular carcinoma (HCC) recurrence after liver transplant is the mainstay of selection tools used by transplant-governing bodies to discern candidacy for patients with HCC. Although progress has been made, few tools incorporate objective measures of tumor biological characteristics, resulting in inclusion of patients with high recurrence rates and exclusion of others who could otherwise be cured.

Objective

To externally validate the New York/California (NYCA) score, a recently published multi-institutional US HCC selection tool that was the first model incorporating a dynamic α-fetoprotein response (AFP-R) and compare the validated score with currently accepted HCC selection tools, namely, the Milan Criteria (MC), the French-AFP (F-AFP), and Metroticket 2.0 models.

Design, Setting, and Participants

A retrospective, multicenter prognostic analysis of prospectively collected databases of 2236 adults undergoing liver transplant for HCC was conducted at 3 US, 1 Canadian, and 4 European centers from January 1, 2001, to December 31, 2013. The AFP-R was measured as the difference between maximum and final pre-liver transplant AFP level. Cox proportional hazards regression and competing risk regression analyses examined recurrence-free and overall survival. Receiver operating characteristic analyses and net reclassification index were used to compare NYCA with MC, F-AFP, and Metroticket 2.0. Data analysis was performed from June 2019 to April 2020.

Main Outcomes and Measures

The primary study outcome was 5-year recurrence-free survival; overall survival was the secondary outcome.

Results

Of 2236 patients, 1808 (80.9%) were men; mean (SD) age was 58.3 (7.96) years. A total of 545 patients (24.4%) did not meet the MC. The NYCA score proved valid on competing risk regression analysis, accurately predicting recurrence-free and overall survival (5-year cumulative incidence of recurrence risk in NYCA risk categories was 9.5% for low-, 20.5%, for acceptable-, and 40.5% for high-risk categories; P < .001 for all). The NYCA also predicted recurrence-free survival on a center-specific level: 453 of 545 patients (83.1%) who did not meet MC, 213 of 308 (69.2%) who did not meet the French-AFP, 292 of 384 (76.1%) who did not meet Metroticket 2.0 would be recategorized into NYCA low- and acceptable-risk groups (>75% 5-year recurrence-free survival). The Harrell C statistic for the validated NYCA score was 0.66 compared with 0.59 for the MC and 0.57 for the F-AFP models (P < .001). The net reclassification index for NYCA was 8.1 vs MC, 12.9 vs F-AFP, and 10.1 vs Metroticket 2.0.

Conclusions and Relevance

This study appears to externally validate the importance of AFP-R in the selection of patients with HCC for liver transplant. The AFP-R represents one of the truly objective measures of biological characteristics available before transplantation. Incorporation of AFP-R into selection criteria allows safe expansion of MC and other models, offering liver transplant to patients with acceptable tumor biological characteristics who would otherwise be denied potential cure.

Long term outcomes and complications of reno-portal anastomosis in liver transplantation: results from a propensity score-based outcome analysis

Diffuse splanchnic vein thrombosis (DSVT) remains a serious challenge in liver transplantation (LT). Reno-portal anastomosis (RPA) has previously been reported as a valid option for management of patients with DSVT during LT. The aim of this study was to evaluate post-transplant renal function and surgical outcomes of patients with DSVT who underwent RPA during LT. Between January 2005 and December 2017, 1270 patients underwent LT at our institution, including 16 with DSVT managed with RPA (RPA group). We compared renal function and surgical outcomes in these patients to outcomes in 48 propensity score (PS)-matched patients without thrombosis (control group), using a 1:3 matching model. The two groups had similar rates of postoperative portal vein thrombosis (PVT), renal dysfunction as measured by estimated glomerular filtration rate (eGFR), and overall postoperative complications (Clavien grade III), although the RPA group had a higher incidence of postoperative upper gastrointestinal (GI) bleeding (31.3% vs 4.2%; P = 0.009) that had no clinical consequence. There were no significant differences in five-year graft and patient survival rates between the groups (P = 0.133 and P = 0.166, respectively). RPA is an established technique in the management of patients with DSVT during LT, with comparable outcomes to patients without thrombosis. Our report is the first to demonstrate similar surgical outcomes, including long-term renal function, in LT recipients with or without RPA.

A surgical method for continuous intraportal infusion of gut microbial metabolites in mice

Gut microbe–derived metabolites influence human physiology and disease. However, establishing mechanistic links between gut microbial metabolites and disease pathogenesis in animal models remains challenging. The major route of absorption for microbe-derived small molecules is venous drainage via the portal vein to the liver. In the event of presystemic hepatic metabolism, the route of metabolite administration becomes critical. To our knowledge, we describe here a novel portal vein cannulation technique using a s.c. implanted osmotic pump to achieve continuous portal vein infusion in mice. We first administered the microbial metabolite trimethylamine (TMA) over 4 weeks, during which increased peripheral plasma levels of TMA and its host liver-derived cometabolite, trimethylamine-N-oxide, were observed when compared with a vehicle control. Next, 4-hydroxyphenylacetic acid (4-HPAA), a microbial metabolite that undergoes extensive presystemic hepatic metabolism, was administered intraportally to examine effects on hepatic gene expression. As expected, hepatic levels of 4-HPAA were elevated when compared with the control group while peripheral plasma 4-HPAA levels remained the same. Moreover, significant changes in the hepatic transcriptome were revealed by an unbiased RNA-Seq approach. Collectively, to our knowledge this work describes a novel method for administering gut microbe–derived metabolites via the portal vein, mimicking their physiologic delivery in vivo.

Management of early hepatocellular carcinoma: results of the Delphi consensus process of the Americas Hepato-Pancreato-Biliary Association

BACKGROUND

There are many potential treatment options for patients with early stage hepatocellular carcinoma (HCC) and practice patterns vary widely. This project aimed to use a Delphi conference to generate consensus regarding the management of small resectable HCC.

METHODS

A base case was established with review by members of AHPBA Research Committee. The Delphi panel of experts reviewed the literature and scored clinical case statements to identify areas of agreement and disagreement. Following initial scoring, discussion was undertaken, questions were amended, and scoring was repeated. This cycle was repeated until no further likelihood of reaching consensus existed.

RESULTS

The panel achieved agreement or disagreement consensus regarding 27 statements. The overarching themes included that resection, ablation, transplantation, or any locoregional therapy as a bridge to transplant were all appropriate modalities for early or recurrent HCC. For larger lesions, consensus was reached that radiofrequency ablation and microwave ablation were not appropriate treatments.

CONCLUSION

Using a validated system for identifying consensus, an expert panel agreed that multiple treatment modalities are appropriate for early stage HCC. These consensus guidelines are intended to help guide physicians through treatment modalities for early HCC; however, clinical decisions should continue to be made on a patient-specific basis.

Posttransplant Outcomes in Older Patients With Hepatocellular Carcinoma Are Driven by Non-Hepatocellular Carcinoma Factors

The incidence of hepatocellular carcinoma (HCC) is growing in the United States, especially among the elderly. Older patients are increasingly receiving transplants as a result of HCC, but the impact of advancing age on long-term posttransplant outcomes is not clear. To study this, we used data from the US Multicenter HCC Transplant Consortium of 4980 patients. We divided the patients into 4 groups by age at transplantation: 18 to 64 years (n = 4001), 65 to 69 years (n = 683), 70 to 74 years (n = 252), and ≥75 years (n = 44). There were no differences in HCC tumor stage, type of bridging locoregional therapy, or explant residual tumor between the groups. Older age was confirmed to be an independent and significant predictor of overall survival even after adjusting for demographic, etiologic, and cancer-related factors on multivariable analysis. A dose-response effect of age on survival was observed, with every 5-year increase in age older than 50 years resulting in an absolute increase of 8.3% in the mortality rate. Competing risk analysis revealed that older patients experienced higher rates of non-HCC-related mortality (P = 0.004), and not HCC-related death (P = 0.24). To delineate the precise cause of death, we further analyzed a single-center cohort of patients who received a transplant as a result of HCC (n = 302). Patients older than 65 years had a higher incidence of de novo cancer (18.1% versus 7.6%; P = 0.006) after transplantation and higher overall cancer-related mortality (14.3% versus 6.6%; P = 0.03). Even carefully selected elderly patients with HCC have significantly worse posttransplant survival rates, which are mostly driven by non-HCC-related causes. Minimizing immunosuppression and closer surveillance for de novo cancers can potentially improve the outcomes in elderly patients who received a transplant as a result of HCC.

Trends and outcomes of simultaneous versus staged resection of synchronous colorectal cancer and colorectal liver metastases

BACKGROUND

The objective of this study was to assess trends in the use as well as the outcomes of patients undergoing simultaneous versus staged resection for synchronous colorectal liver metastases.

METHODS

Patients undergoing resection for colorectal liver metastases between 2008 and 2018 were identified using a multi-institutional database. Trends in use and outcomes of simultaneous resection of colorectal liver metastases were examined over time and compared with that of staged resection after propensity score matching.

RESULTS

Among 1,116 patients undergoing resection for colorectal liver metastases, 690 (61.8%) patients had synchronous disease. Among them, 314 (45.5%) patients underwent simultaneous resection, while 376 (54.5%) had staged resection. The proportion of patients undergoing simultaneous resection for synchronous colorectal liver metastases increased over time (2008: 37.2% vs 2018: 47.4%; p_trend = 0.02). After propensity score matching (n = 201 per group), patients undergoing simultaneous resection for synchronous colorectal liver metastases had a higher incidence of overall (44.8% vs 34.3%; P = .03) and severe complications (Clavien-Dindo ≥III) (16.9% vs 7.0%; P = .002) yet comparable 90-day mortality (3.5% vs 1.0%; P = .09) compared with patients undergoing staged resection. The incidence of severe morbidity decreased over time (2008: 50% vs 2018: 11.1%; p_trend = 0.02). Survival was comparable among patients undergoing simultaneous versus staged resection of colorectal liver metastases (3-year overall survival: 66.1% vs 62.3%; P = .67). Following simultaneous resection, severe morbidity and mortality increased incrementally based on the extent of liver resection and complexity of colectomy.

CONCLUSION

While simultaneous resection was associated with increased morbidity, the incidence of severe morbidity decreased over time. Long-term survival was comparable after simultaneous resection versus staged resection of colorectal liver metastases.

Very Early Recurrence After Liver Resection for Intrahepatic Cholangiocarcinoma: Considering Alternative Treatment Approaches

Importance

Although surgery offers the best chance of a potential cure for patients with localized, resectable intrahepatic cholangiocarcinoma (ICC), prognosis of patients remains dismal largely because of a high incidence of recurrence.

Objective

To predict very early recurrence (VER) (ie, recurrence within 6 months after surgery) following resection for ICC in the pre- and postoperative setting.

Design, Setting, and Participants

Patients who underwent curative-intent resection for ICC between May 1990 and July 2016 were identified from an international multi-institutional database. The study was conducted at The Ohio State University in collaboration with all other participating institutions. The data were analyzed in December 2019.

Main Outcomes and Measures

Two logistic regression models were constructed to predict VER based on pre- and postoperative variables. The final models were used to develop an online calculator to predict VER and the tool was internally and externally validated.

Results

Among 880 patients (median age, 59 years [interquartile range, 51-68 years]; 388 women [44.1%]; 428 [50.2%] white; 377 [44.3%] Asian; 27 [3.2%] black]), 196 (22.3%) developed VER. The 5-year overall survival among patients with and without VER was 8.9% vs 49.8%, respectively (P < .001). A preoperative model was able to stratify patients relative to the risk for VER: low risk (6-month recurrence-free survival [RFS], 87.7%), intermediate risk (6-month RFS, 72.3%), and high risk (6-month RFS, 49.5%) (log-rank P < .001). The postoperative model similarly identified discrete cohorts of patients based on probability for VER: low risk (6-month RFS, 90.0%), intermediate risk (6-month RFS, 73.1%), and high risk (6-month RFS, 48.5%) (log-rank, P < .001). The calibration and predictive accuracy of the pre- and postoperative models were good in the training (C index: preoperative, 0.710; postoperative, 0.722) as well as the internal (C index: preoperative, 0.715; postoperative, 0.728; bootstrapping resamples, n = 5000) and external (C index: postoperative, 0.672) validation data sets.

Conclusion and Relevance

An easy-to-use online calculator was developed to help clinicians predict the chance of VER after curative-intent resection for ICC. The tool performed well on internal and external validation. This tool may help clinicians in the preoperative selection of patients for neoadjuvant therapy as well as during the postoperative period to inform surveillance strategies.

Resection of Colorectal Liver Metastasis: Prognostic Impact of Tumor Burden vs KRAS Mutational Status

BACKGROUND

The prognostic impact of colorectal liver metastasis (CRLM) morphologic characteristics relative to KRAS mutational status after hepatic resection remains ill defined.

STUDY DESIGN

Patients undergoing hepatectomy for CRLM between 2001 and 2018 were identified using an international multi-institutional database. Tumor burden score (TBS) was defined as distance from origin on a Cartesian plane that incorporated maximum tumor size (x-axis) and number of lesions (y-axis). Impact of TBS on overall survival (OS) relative to KRAS status (wild type [wtKRAS] vs mutated [mutKRAS]) was assessed.

RESULTS

Among 1,361 patients, the median number of metastatic lesions was 2 (interquartile range [IQR] 1-3), and median size of the largest metastatic lesion was 3.0 cm (IQR 2.0-5.0 cm), resulting in a median TBS of 4.1 (IQR 2.8-6.1); KRAS status was wtKRAS (n = 420, 30.9%), mutKRAS (n = 251, 18.4%), and unknown (n = 690, 50.7%). Overall median and 5-year OS were 49.5 months (95%CI 45.2-53.8) and 43.2%, respectively. In examining the entire cohort, TBS was associated with long-term prognosis (5-year OS, low TBS: 49.4% vs high TBS: 36.7%), as was KRAS mutational status (5-year OS, wtKRAS: 48.2% vs mutKRAS: 31.1%; unknown KRAS: 44.0%)(both p < 0.01). Among patients with wtKRAS tumors, TBS was strongly associated with improved OS (5-year OS, low TBS: 59.1% vs high TBS: 38.4%, p = 0.002); however, TBS failed to discriminate long-term prognosis among patients with mutKRAS tumors (5-year OS, low TBS: 37.4% vs high TBS: 26.7%, p = 0.19). In fact, patients with high TBS/wtKRAS CRLM had comparable outcomes to patients with low TBS/mutKRAS tumors (5-year OS, 38.4% vs 37.4%, respectively; p = 0.59). On multivariable analysis, while TBS was associated with OS among patients with wtKRAS CRLM (hazard ratio 1.43, 95%CI 1.02-2.00; p = 0.03), TBS was not an independent predictor of survival among patients with mutKRAS CRLM (HR 1.36, 95%CI 0.92-1.99; p = 0.12).

CONCLUSIONS

While TBS was associated with survival among patients with wtKRAS tumors, CRLM morphology was not predictive of long-term outcomes among patients with mutKRAS CRLM.

Liver Transplantation Outcomes in a U.S. Multicenter Cohort of 789 Patients With Hepatocellular Carcinoma Presenting Beyond Milan Criteria

BACKGROUND AND AIMS

The Organ Procurement and Transplantation Network recently approved liver transplant (LT) prioritization for patients with hepatocellular carcinoma (HCC) beyond Milan Criteria (MC) who are down-staged (DS) with locoregional therapy (LRT). We evaluated post-LT outcomes, predictors of down-staging, and the impact of LRT in patients with beyond-MC HCC from the U.S. Multicenter HCC Transplant Consortium (20 centers, 2002-2013).

APPROACH AND RESULTS

Clinicopathologic characteristics, overall survival (OS), recurrence-free survival (RFS), and HCC recurrence (HCC-R) were compared between patients within MC (n = 3,570) and beyond MC (n = 789) who were down-staged (DS, n = 465), treated with LRT and not down-staged (LRT-NoDS, n = 242), or untreated (NoLRT-NoDS, n = 82). Five-year post-LT OS and RFS was higher in MC (71.3% and 68.2%) compared with DS (64.3% and 59.5%) and was lowest in NoDS (n = 324; 60.2% and 53.8%; overall P < 0.001). DS patients had superior RFS (60% vs. 54%, P = 0.043) and lower 5-year HCC-R (18% vs. 32%, P < 0.001) compared with NoDS, with further stratification by maximum radiologic tumor diameter (5-year HCC-R of 15.5% in DS/<5 cm and 39.1% in NoDS/>5 cm, P < 0.001). Multivariate predictors of down-staging included alpha-fetoprotein response to LRT, pathologic tumor number and size, and wait time >12 months. LRT-NoDS had greater HCC-R compared with NoLRT-NoDS (34.1% vs. 26.1%, P < 0.001), even after controlling for clinicopathologic variables (hazard ratio [HR] = 2.33, P < 0.001) and inverse probability of treatment-weighted propensity matching (HR = 1.82, P < 0.001).

CONCLUSIONS

In LT recipients with HCC presenting beyond MC, successful down-staging is predicted by wait time, alpha-fetoprotein response to LRT, and tumor burden and results in excellent post-LT outcomes, justifying expansion of LT criteria. In LRT-NoDS patients, higher HCC-R compared with NoLRT-NoDS cannot be explained by clinicopathologic differences, suggesting a potentially aggravating role of LRT in patients with poor tumor biology that warrants further investigation.

Tumor Burden Dictates Prognosis Among Patients Undergoing Resection of Intrahepatic Cholangiocarcinoma: A Tool to Guide Post-Resection Adjuvant Chemotherapy?

INTRODUCTION

While tumor burden (TB) has been associated with outcomes among patients with hepatocellular carcinoma, the role of overall TB in intrahepatic cholangiocarcinoma (ICC) remains poorly defined.

METHODS

Patients undergoing curative-intent resection of ICC between 2000 and 2017 were identified from a multi-institutional database. The impact of TB on overall (OS) and disease-free survival (DFS) was evaluated in the multi-institutional database and validated externally.

RESULTS

Among 1101 patients who underwent curative-intent resection of ICC, 624 (56.7%) had low TB, 346 (31.4%) medium TB, and 131 (11.9%) high TB. OS incrementally worsened with higher TB (5-year OS; low TB: 48.3% vs medium TB: 29.8% vs high TB: 17.3%, p < 0.001). Similarly, patients with low TB had better DFS compared with medium and high TB patients (5-year DFS: 38.3% vs 18.7% vs 6.9%, p < 0.001). On multivariable analysis, TB was independently associated with OS (medium TB: HR = 1.40, 95% CI 1.14-1.71; high TB: HR = 1.89, 95% CI 1.46-2.45) and DFS (medium TB, HR = 1.61, 95% CI 1.33-1.96; high TB: HR = 2.03, 95% CI 1.56-2.64). Survival analysis revealed an excellent prognostic discrimination using the TB among the external validation cohort (3-year OS; low TB: 44.8%, medium TB: 29.3%; high TB: 23.3%, p = 0.03; 3-year DFS: low TB: 32.7%, medium TB: 10.7%; high TB: 0%, p < 0.001). While neoadjuvant chemotherapy was not associated with survival across the TB groups, receipt of adjuvant chemotherapy was associated with increased survival among patients with high TB (5-year OS: 24.4% vs 13.4%, p = 0.02).

CONCLUSION

Overall TB dictated prognosis among patients with resectable ICC. TB may be used as a tool to help guide post-resection treatment strategies.