The aMAP score predicts long-term outcomes after resection of hepatocellular carcinoma: a multi-institutional analysis

BACKGROUND

The aMAP score is a proposed model to predict the development of hepatocellular carcinoma (HCC) among high-risk patients with chronic hepatitis. The role of the aMAP score to predict long-term survival among patients following resection of HCC has not been determined.

METHODS

Patients undergoing resection for HCC between 2000 and 2020 were identified using a multi-institutional database. The impact of the aMAP score on long-term outcomes following HCC resection was assessed.

RESULTS

Among 1377 patients undergoing resection for HCC, a total of 972 (70.6 %) patients had a low aMAP score (≤63), whereas 405 (29.4 %) individuals had a high aMAP score (≥64). aMAP score was associated with 5-year OS in the entire cohort (low vs high aMAP score:66.5 % vs. 54.3 %, p < 0.001). aMAP score predicted 5-year OS following resection among patients with HBV-HCC (low vs. high aMAP:68.8 % vs. 55.6 %, p = 0.01) and NASH/other-HCC (64.7 % vs. 53.7, p = 0.04). aMAP score could sub-stratify 5-year OS among patients undergoing HCC resection within (low vs. high aMAP:81.5 % vs. 67.4 %, p < 0.001) and beyond (55.9 % vs. 38.8 %, p < 0.001) Milan criteria.

DISCUSSION

The aMAP score predicted postoperative outcomes following resection of HCC within and beyond Milan criteria. Apart from a surveillance tool, the aMAP score can also be used as a prognostic tool among patients undergoing resection of HCC.

Textbook outcome in liver surgery: open vs minimally invasive hepatectomy among patients with hepatocellular carcinoma

BACKGROUND

We sought to investigate whether minimally invasive hepatectomy (MIH) was superior to open hepatectomy (OH) in terms of achieving textbook outcome in liver surgery (TOLS) after resection of hepatocellular carcinoma (HCC).

METHODS

Patients who underwent resection of HCC between 2000 and 2020 were identified from an international database. TOLS was defined by the absence of intraoperative grade ≥2 events, R1 resection margin, posthepatectomy liver failure, bile leakage, major complications, in-hospital mortality, and readmission.

RESULTS

A total of 1039 patients who underwent HCC resection were included in the analysis. Although most patients underwent OH (n = 724 [69.7%]), 30.3% (n = 315) underwent MIH. Patients who underwent MIH had a lower tumor burden score (3.6 [IQR, 2.6-5.2] for MIH vs 6.1 [IQR, 3.9-10.1] for OH) and were more likely to undergo minor hepatectomy (84.1% [MIH] vs 53.6% [OH]) than patients who had an OH (both P < .001). After propensity score matching to control for baseline differences between the 2 cohorts, the incidence of TOLS was comparable among patients who had undergone MIH (56.6%) versus OH (64.8%) (P = .06). However, MIH was associated with a shorter length of hospital stay (6.0 days [IQR, 4.0-8.0] for MIH vs 9.0 days [IQR, 6.0-12.0] for OH). Among patients who had MIH, the odds ratio of achieving TOLS remained stable up to a tumor burden score of 4; after which the chance of TOLS with MIH markedly decreased.

CONCLUSION

Patients with HCC who underwent resection with MIH versus OH had a comparable likelihood of TOLS, although MIH was associated with a short length of stay.

Perioperative Lymphopenia is Associated with Increased Risk of Recurrence and Worse Survival Following Hepatectomy for Hepatocellular Carcinoma

INTRODUCTION

Immune dysregulation may be associated with cancer progression. We sought to investigate the prognostic value of perioperative lymphopenia on short- and long-term outcomes among patients undergoing resection of hepatocellular carcinoma (HCC).

METHODS

Patients undergoing resection of HCC between 2000 and 2020 were identified using an international database. The incidence and impact of perioperative lymphopenia [preoperative, postoperative day (POD) 1/3/5], defined as absolute lymphocyte count (ALC) <1000/μL, on short- and long-term outcomes was assessed.

RESULTS

Among 1448 patients, median preoperative ALC was 1593/μL [interquartile range (IQR) 1208-2006]. The incidence of preoperative lymphopenia was 14.0%, and 50.2%, 45.1% and 35.6% on POD1, POD3 and POD5, respectively. Preoperative lymphopenia predicted 5-year overall survival (OS) [lymphopenia vs. no lymphopenia: 49.1% vs. 66.1%] and 5-year disease-free survival (DFS) [25.0% vs. 41.5%] (both p < 0.05). Lymphopenia on POD1 (5-year OS: 57.1% vs. 71.2%; 5-year DFS: 30.0% vs. 41.1%), POD3 (5-year OS: 57.3% vs. 68.9%; 5-year DFS: 35.4% vs. 42.7%), and POD5 (5-year OS: 53.1% vs. 66.1%; 5-year DFS: 32.8% vs. 42.3%) was associated with worse long-term outcomes (all p < 0.05). Patients with severe lymphopenia (ALC <500/μL) on POD5 had worse 5-year OS and DFS (5-year OS: 44.7% vs. 54.3% vs. 66.1%; 5-year DFS: 27.8% vs. 33.3% vs. 42.3%) [both p < 0.05], as well as higher incidence of overall (45.5% vs. 25.3% vs. 30.9%; p = 0.013) and major complications (18.2% vs. 3.4% vs. 4.5%; p < 0.001) versus individuals with moderate (ALC 500-1000/μL) or no lymphopenia following hepatectomy for HCC. After adjusting for competing risk factors, prolonged lymphopenia was independently associated with higher hazards of death [hazard ratio (HR) 1.38, 95% CI 1.11-1.72] and recurrence (HR 1.22, 95% CI 1.02-1.45).

CONCLUSION

Perioperative lymphopenia had short- and long-term prognostic implications among individuals undergoing hepatectomy for HCC.

A Prognostic Model To Predict Survival After Recurrence Among Patients With Recurrent Hepatocellular Carcinoma

OBJECTIVE

We sought to develop and validate a preoperative model to predict survival after recurrence (SAR) in hepatocellular carcinoma (HCC).

BACKGROUND

Although HCC is characterized by recurrence as high as 60%, models to predict outcomes after recurrence remain relatively unexplored.

METHODS

Patients who developed recurrent HCC between 2000 and 2020 were identified from an international multi-institutional database. Clinicopathologic data on primary disease and laboratory and radiologic imaging data on recurrent disease were collected. Multivariable Cox regression analysis and internal bootstrap validation (5000 repetitions) were used to develop and validate the SARScore. Optimal Survival Tree analysis was used to characterize SAR among patients treated with various treatment modalities.

RESULTS

Among 497 patients who developed recurrent HCC, median SAR was 41.2 months (95% CI 38.1-52.0). The presence of cirrhosis, number of primary tumors, primary macrovascular invasion, primary R1 resection margin, AFP>400 ng/mL on the diagnosis of recurrent disease, radiologic extrahepatic recurrence, radiologic size and number of recurrent lesions, radiologic recurrent bilobar disease, and early recurrence (≤24 months) were included in the model. The SARScore successfully stratified 1-, 3- and 5-year SAR and demonstrated strong discriminatory ability (3-year AUC: 0.75, 95% CI 0.70-0.79). While a subset of patients benefitted from resection/ablation, Optimal Survival Tree analysis revealed that patients with high SARScore disease had the worst outcomes (5-year AUC; training: 0.79 vs. testing: 0.71). The SARScore model was made available online for ease of use and clinical applicability ( https://yutaka-endo.shinyapps.io/SARScore/ ).

CONCLUSION

The SARScore demonstrated strong discriminatory ability and may be a clinically useful tool to help stratify risk and guide treatment for patients with recurrent HCC.

Modified integrated tumor burden, liver function, systemic inflammation, and tumor biology score to predict long-term outcomes after resection for hepatocellular carcinoma

BACKGROUND

A preoperative predictive score for hepatocellular carcinoma (HCC) can help stratify patients who undergo resection relative to long-term outcomes and tailor treatment strategies.

METHODS

Patients who underwent curative-intent hepatectomy for HCC between 2000 and 2020 were identified from an international multi-institutional database. A risk score (mFIBA) was developed using an Eastern cohort and then validated using a Western cohort.

RESULTS

Among 957 patients, 443 and 514 patients were included from the Eastern and Western cohorts, respectively. On multivariable analysis, alpha-feto protein (HR1.97, 95%CI 1.42-2.72), neutrophil-to-lymphocyte ratio (HR1.74, 95%CI 1.28-2.38), albumin-bilirubin grade (HR1.66, 95%CI 1.21-2.28), and imaging tumor burden score (HR1.25, 95%CI 1.12-1.40) were associated with OS. The c-index in the Eastern test and Western validation cohorts were 0.69 and 0.67, respectively. Notably, mFIBA score outperformed previous HCC staging systems. 5-year OS incrementally decreased with an increase in mFIBA. On multivariable Cox regression analysis, the mFIBA score was associated with worse OS (HR1.18, 95%CI 1.13-1.23) and higher risk of recurrence (HR1.16, 95%CI 1.11-1.20). An easy-to-use calculator of the mFIBA score was made available online (https://yutaka-endo.shinyapps.io/mFIBA_score/).

DISCUSSION

The online mFIBA calculator may help surgeons with clinical decision-making to individualize perioperative treatment strategies for patients undergoing resection of HCC.

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.

Machine-Based Learning Hierarchical Cluster Analysis: Sex-Based Differences in Prognosis Following Resection of Hepatocellular Carcinoma

BACKGROUND

Patients with hepatocellular carcinoma (HCC) may have a heterogeneous presentation, as well as different long-term outcomes following surgical resection. We sought to use machine learning to cluster patients into different prognostic groups based on preoperative characteristics.

METHODS

Patients who underwent curative-intent liver resection for HCC between 2000 and 2020 were identified from a large international multi-institutional database. A hierarchical cluster analysis was performed based on preoperative factors to characterize patterns of presentation and define disease-free survival (DFS).

RESULTS

Among 966 with HCC, 3 distinct clusters were identified: Cluster 1 (n = 160, 16.5%), Cluster 2 (n = 537, 55.6%) and Cluster 3 (n = 269, 27.8%). Cluster 1 (n = 160, 16.5%) consisted of female patients (n = 160, 100%), low inflammation-based scores, intermediate tumor burden score (TBS) (median: 4.71) and high alpha-fetoprotein (AFP) levels (median 41.3 ng/mL); Cluster 2 consisted of male individuals (n = 537, 100%), mainly with a history of HBV infection (n = 429, 79.9%), low inflammation-based scores, intermediate AFP levels (median 26.0 ng/mL) and lower TBS (median 4.49); Cluster 3 was comprised of older patients (median age 68 years) predominantly male (n = 248, 92.2%) who had low incidence of HBV/HCV infection (7.1% and 8.2%, respectively), intermediate AFP levels (median 16.8 ng/mL), high inflammation-based scores and high TBS (median 6.58). Median DFS worsened incrementally among the three different clusters with Cluster 3 having the lowest DFS (Cluster 1: median not reached; Cluster 2: 34 months, 95% CI 23.0-48.0, Cluster 3: 19 months, 95% CI 15.0-29.0, p < 0.05).

CONCLUSION

Cluster analysis classified HCC patients into three distinct prognostic groups. Cluster assignment predicted DFS following resection of HCC with the female cluster having the most favorable prognosis following HCC resection.

Ancestry-attenuated effects of socioeconomic deprivation on type 2 diabetes disparities in the All of Us cohort

Background

Diabetes is a common disease with a major burden on morbidity, mortality, and productivity. Type 2 diabetes (T2D) accounts for roughly 90% of all diabetes cases in the USA and has a greater observed prevalence among those who identify as Black or Hispanic.

Methods

This study aimed to assess T2D racial and ethnic disparities using the All of Us Research Program data and to measure associations between genetic ancestry (GA), socioeconomic deprivation, and T2D. We used the All of Us Researcher Workbench to analyze T2D prevalence and model its associations with GA, individual-level (iSDI), and zip code-based (zSDI) socioeconomic deprivation indices among participant self-identified race and ethnicity (SIRE) groups.

Results

The study cohort of 86,488 participants from the four largest SIRE groups in All of Us: Asian (n = 2311), Black (n = 16,282), Hispanic (n = 16,966), and White (n = 50,292). SIRE groups show characteristic genetic ancestry patterns, consistent with their diverse origins, together with a continuum of ancestry fractions within and between groups. The Black and Hispanic groups show the highest levels of socioeconomic deprivation, followed by the Asian and White groups. Black participants show the highest age- and sex-adjusted T2D prevalence (21.9%), followed by the Hispanic (19.9%), Asian (15.1%), and White (14.8%) groups. Minority SIRE groups and socioeconomic deprivation, both iSDI and zSDI, are positively associated with T2D, when the entire cohort is analyzed together. However, SIRE and GA both show negative interaction effects with iSDI and zSDI on T2D. Higher levels of iSDI and zSDI are negatively associated with T2D in the Black and Hispanic groups, and higher levels of iSDI and zSDI are negatively associated with T2D at high levels of African and Native American ancestry.

Conclusions

Socioeconomic deprivation is associated with a higher prevalence of T2D in Black and Hispanic minority groups, compared to the majority White group. Nonetheless, socioeconomic deprivation is associated with reduced T2D risk within the Black and Hispanic groups. These results are paradoxical and have not been reported elsewhere, with possible explanations related to the nature of the All of Us data along with SIRE group differences in access to healthcare, diet, and lifestyle.

Evolution of laparoscopic pancreaticoduodenectomy at Westmead Hospital

BACKGROUND

Despite its proposed benefits, laparoscopic pancreaticoduodenectomy (LPD) has not been widely adopted due to its technical complexity and steep learning curve. The aim of this study was to report a single surgeon's experience in the stepwise implementation of LPD and evolution of technique over a nine-year period in a moderate-high volume unit.

METHODS

Carefully selected patients underwent LPD initially by hybrid approach (laparoscopic resection and open reconstruction), which evolved into a total LPD (laparoscopic resection and reconstruction). Data was prospectively collected to include patient characteristics, intraoperative data, evolution of technique and postoperative outcomes.

RESULTS

A total of 25 patients underwent hybrid LPD (HLPD) and 20 patients underwent total LPD (TLPD). There was no 90-day mortality. Three patients developed a postoperative pancreatic fistula (POPF), all of which occurred in patients undergoing HLPD. There was no POPF in 20 consecutive TLPD. There was no evidence of anastomotic strictures in the hepaticojejunostomy in patients undergoing TLPD at long term follow up.

CONCLUSION

A gradual and cautious progression from HLPD to TLPD is essential to ensure safe implementation into a unit. LPD should only be considered in carefully selected patients, with outcomes subjected to regular and rigorous independent audit.

Impact of an interdisciplinary patient care model and routine screening on clinical outcomes in patients with hepatitis C

Testing for hepatitis C in hospital emergency departments (ED) and linkage to care to clinics have been reported to provide the most opportunity for screening patients and facilitating continuum of care. Treatment model initiatives have expanded to include telehealth services and open treatment capacity to non-physician providers, such as pharmacists. This study's objective was to assess the impact of implementing automated routine screening for hepatitis C virus (HCV) and a clinical pharmacist into the interdisciplinary care model on HCV diagnosis and treatment outcomes. This retrospective cohort study compared outcomes in a pre-intervention and post-intervention group. Patients were screened and diagnosed with HCV at Jersey City Medical Center (JCMC) and completed linkage to care at JCMC Center for Comprehensive Care. Interventions were the implementation of automated routine HCV screening in the ED and addition of a clinical pharmacist to the interdisciplinary patient care model. Primary endpoints analyzed the number of patients who have achieved sustained virologic response after 12 weeks of treatment (SVR12) and patients who have completed treatment with no reported record of SVR12. Secondary endpoints analyzed the number of patients lost to follow-up, appointment type, time spent in appointments, and clinical pharmacist specialist interventions. Data was collected as categorical variables and chi-squared tests assessed if there were differences between the two samples. Data was collected from 46 patients in the pre-intervention group and 37 patients in the post-intervention group. Patients consisted of mostly males. Ages ranged from 27 to 83 years old. Race included Black, White, Asian, and Other. This study's results showed the positive impact on implementation of routine screening, telehealth services, and an interdisciplinary team approach to HCV diagnosis and management. Given the timeframe, it also showed the potential positive impact on these interventions during a global pandemic.

Cascade Multi-Level Transformer Network for Surgical Workflow Analysis

Surgical workflow analysis aims to recognise surgical phases from untrimmed surgical videos. It is an integral component for enabling context-aware computer-aided surgical operating systems. Many deep learning-based methods have been developed for this task. However, most existing works aggregate homogeneous temporal context for all frames at a single level and neglect the fact that each frame has its specific need for information at multiple levels for accurate phase prediction. To fill this gap, in this paper we propose Cascade Multi-Level Transformer Network (CMTNet) composed of cascaded Adaptive Multi-Level Context Aggregation (AMCA) modules. Each AMCA module first extracts temporal context at the frame level and the phase level and then fuses frame-specific spatial feature, frame-level temporal context, and phase-level temporal context for each frame adaptively. By cascading multiple AMCA modules, CMTNet is able to gradually enrich the representation of each frame with the multi-level semantics that it specifically requires, achieving better phase prediction in a frame-adaptive manner. In addition, we propose a novel refinement loss for CMTNet, which explicitly guides each AMCA module to focus on extracting the key context for refining the prediction of the previous stage in terms of both prediction confidence and smoothness. This further enhances the quality of the extracted context effectively. Extensive experiments on the Cholec80 and the M2CAI datasets demonstrate that CMTNet achieves state-of-the-art performance.

Impact of Surgical Margin Width on Prognosis Following Resection of Hepatocellular Carcinoma Varies on the Basis of Preoperative Alpha-Feto Protein and Tumor Burden Score

BACKGROUND

We sought to examine the prognostic impact of margin width at time of hepatocellular carcinoma (HCC) resection relative to the alpha-feto protein tumor burden score (ATS).

PATIENTS AND METHODS

Patients who underwent curative-intent hepatectomy for HCC between 2000 and 2020 were identified from a multi-institutional database. The impact of margin width on overall survival and recurrence-free survival was examined relative to ATS using univariable and multivariable analyses.

RESULTS

Among 782 patients with HCC who underwent resection, median ATS was 6.5 [interquartile range (IQR) 4.3-10.2]. Most patients underwent R0 resection (n = 613, 78.4%); among patients who had an R0 resection, 325 (41.6%) had a margin width > 5 mm while 288 (36.8%) had a 0-5 mm margin width. Among patients with high ATS, an increasing margin width was associated with incrementally better overall and recurrence-free survival. In contrast, among patients with low ATS, margin width was not associated with long-term outcomes. On multivariable Cox regression analysis, each unit increase in ATS was independently associated with a 7% higher risk of death [hazard ratio (HR) 1.07; 95% confidence interval (CI) 1.03-1.11, p < 0.001]. While the incidence of early recurrence was not associated with margin width among patients with low ATS, wider margin width was associated with an incrementally lower incidence of early recurrence among patients with high ATS.

CONCLUSION

ATS, an easy-to-use composite tumor-related metric, was able to risk stratify patients following resection of HCC relative to overall survival and recurrence-free survival. The therapeutic impact of resection margin width had a variable impact on long-term outcomes relative to ATS.

Ancestry-attenuated effects of socioeconomic deprivation on type 2 diabetes disparities in the All of Us cohort

Background

Diabetes is a common disease with a major burden on morbidity, mortality, and productivity. Type 2 diabetes (T2D) accounts for roughly 90% of all diabetes cases in the United States and has greater observed prevalence among those who identify as Black or Hispanic.

Methods

The aims of this study were to determine whether T2D racial and ethnic disparities can be observed in data from the All of Us Research Program and to measure associations of genetic ancestry (GA) and socioeconomic deprivation with T2D. The All of Us Researcher Workbench was used to calculate T2D prevalence and to model T2D associations with GA, individual-level (iSDI) and zip code-based (zSDI) socioeconomic deprivation indices within and between participant self-identified race and ethnicity (SIRE) groups.

Results

The study cohort of 86,488 participants from the four largest SIRE groups in All of Us: Asian (n=2,311), Black (n=16,282), Hispanic (n=16,966), and White (n=50,292). SIRE groups show characteristic genetic ancestry patterns, consistent with their diverse origins, together with a continuum of ancestry fractions within and between groups. The Black and Hispanic groups show the highest median SDI values, followed by the Asian and White groups. Black participants show the highest age- and sex-adjusted T2D prevalence (21.9%), followed by the Hispanic (19.9%), Asian (15.1%), and White (14.8%) groups. Minority SIRE groups and socioeconomic deprivation are positively associated with T2D, when the entire cohort is analyzed together. However, SIRE and GA both show negative interaction effects with SDI on T2D. Higher levels of SDI are negatively associated with T2D in the Black and Hispanic groups, and higher levels of SDI are negatively associated with T2D at high levels of African and Native American ancestry.

Conclusion

Socioeconomic deprivation is positively associated with the SIRE group T2D disparities observed here but negatively associated with T2D within the Black and Hispanic groups that show the highest T2D prevalence. These results are paradoxical and have not been reported elsewhere. We discuss possible explanations for this paradox related to the nature of the All of Us data along with SIRE group differences in access to healthcare, diet, and lifestyle.

Laws beyond spacetime

Quantum gravity's suggestion that spacetime may be emergent and so only exist contingently would force a radical reconception of extant analyses of laws of nature. Humeanism presupposes a spatiotemporal mosaic of particular matters of fact on which laws supervene; primitivism and dispositionalism conceive of the action of primitive laws or of dispositions as a process of 'nomic production' unfolding over time. We show how the Humean supervenience basis of non-modal facts and primitivist or dispositionalist accounts of nomic production can be reconceived, avoiding a reliance on fundamental spacetime. However, it is unclear that naturalistic forms of Humeanism can maintain their commitment to there being no necessary connections among distinct entities. Furthermore, non-temporal conceptions of production render this central concept more elusive than before. In fact, the challenges run so deep that the survival of the investigated analyses into the era of quantum gravity is questionable.

Machine learning and the quest for objectivity in climate model parameterization

Parameterization and parameter tuning are central aspects of climate modeling, and there is widespread consensus that these procedures involve certain subjective elements. Even if the use of these subjective elements is not necessarily epistemically problematic, there is an intuitive appeal for replacing them with more objective (automated) methods, such as machine learning. Relying on several case studies, we argue that, while machine learning techniques may help to improve climate model parameterization in several ways, they still require expert judgment that involves subjective elements not so different from the ones arising in standard parameterization and tuning. The use of machine learning in parameterizations is an art as well as a science and requires careful supervision.

A Wireless Wearable Patch for Remote Monitoring of Respiratory and Cardiac Rhythm in Children

Remote patient monitoring (RPM) is an innovative strategy to promote health and improve patient management and care. Recent advances in healthcare technologies have seen the emergence of wearable sensors allowing longitudinal physiological measurements in any environment. This paper introduces a wireless wearable patch 'Leo' for continuous remote monitoring of physiological data at home and healthcare settings. This includes single lead ECG, chest impedance, heart rate (HR), respiration rate (RR) and body posture. To test Leo's ability to capture longitudinal physiological data at home, 15 children experiencing acute severe asthma exacerbations were recruited during their emergency department (ED) visits. Participants wore the Leo device for 7 (+/-2) days post-hospital discharge. Nocturnal RR and HR and variability were higher during the first half of the night on Day1 compared to Day7 (p<0.005). Participants also completed a usability questionnaire and reported the patch wear to be comfortable (average score of 3.3 out of 5) and easy to wear during the night (average score of 3.5 out of 5) with 5/15 (33%) reported very slight barely perceptible skin irritation/redness and 2 (13%) reported well defined skin irritation and redness.Clinical Relevance- These results highlight the potential use of the Leo device in clinical practice for continuous un-obstructive monitoring of diseased populations, such as asthma.

Ecodesign and Operational Strategies to Reduce the Carbon Footprint of MRI for Energy Cost Savings

Background Radiology is a major contributor to health care's climate footprint due to energy-intensive devices, particularly MRI which uses the most energy. Purpose To determine the energy, cost, and carbon savings that could be achieved through different scanner power management strategies. Materials and Methods In this retrospective evaluation, four outpatient MRI scanners from three vendors were individually equipped with power meters (1-Hz sampling rate). Power measurement logs were extracted over 39 days. Data were segmented into off, idle, prepared-to-scan, scan, or power-save modes for each scanner. Energy, cost (assuming a mean cost of $0.14 per kilowatt hour), and carbon savings were calculated for the lowest scanner activity modes. Data was summarized using descriptive statistics and 95% confidence intervals. Results Projected annual energy consumption per scanner ranged from 82.7-171.1 megawatt-hours (MWh), with 72-91% defined as nonproductive. Power draws for each mode were measured as 6.4 ± 0.1 kW (power-save), 7.3 ± 0.6 kW to 9.7 ± 0.2 kW (off), 9.5 ± 0.9 to 14.5 ± 0.5 kW (idle), 17.3 ± 0.5 to 25.6 ± 0.6 kW (prepared-to-scan), and 28.6 ± 8.6 to 48.3 ± 11.8 kW (scan). Switching MRIs from idle to off mode for 12 overnight hours reduced power consumption by 25-33%, translating to a potential annual savings of 12.3-21.0 MWh, $1717-$2943 U.S. dollars, and 8.7-14.9 metric tons of CO2-equivalent (MTCO2eq). The power-save mode further reduced consumption by 22-28% compared to off mode, potentially saving an additional 8.8-11.4 MWh, $1,226-$1,594 U.S. dollars, and 6.2-8.1 MTCO2eq per year for 12 hours overnight. Implementation of a power-save mode for 12 hours overnight on all U.S. outpatient MRI in the U.S. could save U.S. health care 58,863.2-76,288.2 MWh, $8.2-$10.7 million U.S. dollars, and 41,606.4-54,088.3 MTCO2eq. Conclusion Powering down MRIs can make radiology departments more energy-efficient and gain substantial sustainability and cost benefits. See also the editorial by Vosshenrich and Heye.

Abstract 4483: Distinct spatial distribution patterns of ALK-inhibitor naïve versus ALK-inhibitor treated ALK-positive NSCLC brain metastases

Background: Non-small cell lung cancer (NSCLC) with anaplastic lymphoma kinase rearrangement (ALK+) has a high affinity to form brain metastases (BrM). The cumulative incidence of BrMs in ALK+ lung cancer is over 50%, despite highly effective ALK tyrosine kinase inhibitors (TKIs) with CNS activity. Pharmacokinetic (PK) data from other CNS-active lung cancer TKIs (e.g., osimertinib) have revealed major brain white vs. gray matter drug concentration differences, raising the possibility of a PK-driven effect on BrM formation and response. This study aims to compare the size and distribution of ALK+ NSCLC BrMs at diagnosis in a TKI-naïve and TKI-exposed cohort.

Methods: We retrospectively reviewed brain MRIs from the date of BrM diagnosis for patients with ALK+ NSCLC at Johns Hopkins. Demographic and clinical information were collected by chart review. Each tumor was marked in a standard space brain model in the corresponding anatomic location represented by a sphere of corresponding diameter using 3D Slicer 4.11. FreeSurfer white-gray matter atlases were used to assess BrM distribution. The data for patients who were on TKI vs TKI-naïve at the time of BrM diagnosis were then analyzed separately. T-tests were used to compare the metastatic burden (sum of BrM diameters), mean BrM diameter per patient, number of BM per patient, per individual mean of white matter exclusive (defined as no overlap with gray matter) and deep white matter (≥5mm away from gray matter) BrMs between patient groups.

Results: 429 BrMs were identified in 39 patients, with 25 patients being TKI-naïve at the time of BrM diagnosis while 14 patients were on TKI therapy. TKI-exposed patients had significantly smaller BrM diameters than those in the TKI-naïve group (6.1±3.8 vs 10.2±5.5mm, p=0.02). While metastatic burden was very similar between the groups, the mean number of BrM per patient was numerically higher in the TKI-exposed group (10.6±11.9 vs 6.2±9.5; p=0.22). Notably, patients in the TKI-exposed group also had higher numbers of white matter exclusive (3.5±4.4 vs 1.4±2.0, p=0.05) and deep white matter metastases (3.2±4.3 vs 1.3±2.0, p=0.06) than those who were TKI-naïve.

Conclusion: Our data highlight the differences in BrM characteristics among ALK+ NSCLC exposed to ALK TKI. TKI therapy was associated with similar BrM burden but smaller individual lesions that were more likely to be exclusive to the white matter where drug concentrations might be significantly lower. These findings suggest that suboptimal drug CNS distribution in the white matter may underly brain progression of ALK+ NSCLC despite TKI therapy. Spatial analyses evaluating ALK TKIs of varying CNS penetrance and later disease time points in more granular anatomic regions are ongoing.

Citation Format: Tia Cheunkarndee, Paola Ganem, Kristen A. Marrone, Joseph C. Murray, Josephine L. Feliciano, Christine L. Hann, Susan C. Scott, David Ettinger, Valsamo Anagnostou, Patrick M. Forde, Julie R. Brahmer, Benjamin P. Levy, Vincent Lam, David O. Kamson. Distinct spatial distribution patterns of ALK-inhibitor naïve versus ALK-inhibitor treated ALK-positive NSCLC brain metastases. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4483.

Abstract 1393: Persistent mutation burden drives sustained anti-tumor immune responses in human cancers

INTRODUCTION: Tumor mutation burden (TMB) is a commonly used biomarker for cancer immunotherapy however TMB only partially captures tumor foreignness. We hypothesized that mutations in single-copy regions of the genome or mutations present in multiple copies (hereafter referred to as persistent mutations) are retained during cancer evolution and immunoediting, may render the tumor continuously visible to the immune system and promote sustained tumor control during immune checkpoint blockade (ICB).

METHODS: We performed pan-cancer analyses of whole exome sequencing data across 31 tumor types in TCGA to quantify the landscape of persistent mutations (n=9,242). We then evaluated the association between persistent tumor mutation burden (pTMB) and ICB response compared to TMB in eight ICB-treated cohorts of patients with NSCLC, melanoma, mesothelioma, and head and neck cancer (n=524). To investigate the clonal evolution of persistent mutations we serially analyzed whole exome sequence data from NSCLCs prior to and at emergence of acquired resistance to ICB. Finally, we evaluated the composition of the tumor microenvironment (TME) in baseline and on-ICB melanomas by RNA sequencing differential enrichment analyses and deconvolution.

RESULTS: Integration of sequence alterations in only-copy and multi-copy states for 9,242 tumors across 31 tumor types revealed a cancer lineage-dependent distribution of persistent mutations that was largely independent of the overall TMB. In evaluating differential classification based on pTMB- vs TMB-high, we found re-classification rates as high as 53% in individual tumor types, with a median reclassification rate of 33% across all tumor types (range 15% - 53%). We then evaluated the clonal composition of persistent mutations and found a wide range of correlations between pTMB and fraction of clonal mutations (Spearman ρ range: -0.11 - 0.59). In ICB-treated cohorts, pTMB better distinguished responding tumors compared to TMB, and a number of mutation and copy-number related features including tumor aneuploidy (melanoma: Mann-Whitney p=2.3e-06, NSLC: p&lt;2.0e-03, mesothelioma p=0.03, HNSCC p=0.05). Using in silico simulations, we found a similar advantage for pTMB when estimated from gene-panel targeted next generation sequencing. To support the biological plausibility of pTMB in the context of tumor evolution, we evaluated the rate loss of persistent mutations in longitudinal analyses of pre- and post-ICB NSCLC and found that a rate of loss significantly lower for persistent compared to loss-prone mutations (odds ratio 61.43, p&lt;2.2e-16). Consistent with our hypothesis, pTMB-high tumors had a more inflamed TME (p&lt;1e-11).

CONCLUSIONS: Persistent mutations represent a biologically distinct subset within the overall TMB that is unlikely to be lost under selective pressure of ICB and may function as an intrinsic driver of sustained immunologic tumor control.

Citation Format: Noushin Niknafs, Archana Balan, Christopher Cherry, Karlijn Hummelink, Kim Monkhorst, Xiaoshan M. Shao, Zineb Belcaid, Kristen A. Marrone, Joseph Murray, Kellie N. Smith, Benjamin Levy, Josephine Feliciano, Christine L. Hann, Vincent Lam, Drew M. Pardoll, Rachel Karchin, Tanguy Y. Seiwert, Julie R. Brahmer, Patrick M. Forde, Victor E. Velculescu, Valsamo K. Anagnostou. Persistent mutation burden drives sustained anti-tumor immune responses in human cancers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1393.

Abstract 4264: The genomic landscape of RET fusions in non-small cell lung cancer and the impact of co-occurring genomic alterations on the efficacy of selective RET inhibitors

Purpose: RET fusions drive oncogenesis in 1-2% of non-small cell lung cancer (NSCLC) and are sensitive to the selective RET inhibitors selpercatinib and pralsetinib. They have also emerged as mechanisms of acquired resistance to other targeted therapies. The genomic landscape of RET fusions and the impact of co-occurring genomic alterations on the efficacy of selective RET inhibitors is yet to be fully described.

Methods: A total of 678 RET fusion-positive samples were analyzed from three cohorts: Guardant360® circulating tumor DNA (ctDNA) (n=467), tissue and/or plasma from the American Association for Cancer Research Project Genomics Evidence Neoplasia Information Exchange (AACR Project GENIE) non-squamous NSCLC cohort (n=161), and the MD Anderson Cancer Center (MDACC) cohort of patients treated with selpercatinib or pralsetinib (n=50). Molecular characteristics were compared across all three cohorts and to the entire non-RET non-squamous NSCLC AACR Project GENIE cohort (n=17770). Fisher’s exact test was used to evaluate the difference in response rate between patient groups, and Cox proportional hazard models were used to calculate hazard ratios for time-to-event endpoints for patients in the MDACC clinical cohort (n=51, 50 patients with RET fusion, 1 patient with RET point mutation).

Results: The most common fusion partner in all cohorts was KIF5B (ctDNA: 73%; GENIE: 69%; MDACC: 71%), followed by CCDC6 (19%; 17%; 18%) and NCOA4 (5%; 1%; 7%). Across all cohorts, co-mutations in TP53 were most common (60%; 34%; 40%) and EGFR, CDKN2A/B, MET, and ATM consistently co-occurred across all cohorts. EGFR co-occurred more frequently with non-KIF5B fusion partners (chi-square p &lt; 0.006). MYC and CCND1 amplifications were enriched in all three cohorts compared to the non-RET cohort. In the MDACC clinical cohort (n=51), the majority were female, never-smokers, with adenocarcinoma histology. The median follow-up time was 28.3 months (95% CI: 15.2 ~ 35 months). Overall response rate (ORR) was 74.4% (95% CI: 58.8 ~ 86.5%), where patients with TP53 mutation had numerically lower ORR compared to patients without TP53 mutation (58.5% vs. 87.5%; p = 0.0632). Median progression-free survival (PFS) time was 16.5 months (95% CI: 13.5 ~ 27.4 months) and KIF5B fusions trended towards worse PFS outcome compared to non-KIF5B fusions (HR: 2.24; 95% CI: 0.88 ~ 5.67; p = 0.0896). TP53 alterations were associated with a significantly worse overall survival (OS) (HR: 2.93; 95% CI: 1.08 ~ 7.95; p = 0.0346).

Conclusion: In the largest RET fusion-positive NSCLC cohort to date, RET fusions frequently co-occurred with other genomic alterations, most commonly in TP53. TP53 alterations are associated with a significant reduction in overall survival in patients treated with the selective RET inhibitors. Additional analysis is underway.

Citation Format: Tuqa Al Khalaf, Simon Heeke, Lei Feng, Leylah M. Drusbosky, Jeff Lewis, Waree Rinsurongkawong, Vadeerat Rinsurongkawong, Jack Lee, Jianjun Zhang, Don Gibbons, Ara Vaporciyan, Vincent Lam, Vivek Subbiah, John Heymach, Yasir Elamin. The genomic landscape of RET fusions in non-small cell lung cancer and the impact of co-occurring genomic alterations on the efficacy of selective RET inhibitors. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4264.

Combining C-reactive protein and quick sequential organ failure assessment (qSOFA) to improve prognostic accuracy for sepsis and mortality in adult inpatients: A systematic review

Background and Aims

Infections are common in hospitals, and if mismanaged can develop into sepsis, a leading cause of death and disability worldwide. This study aimed to examine whether combining C-reactive protein (CRP) with the quick sequential organ failure assessment (qSOFA) improves its accuracy for predicting mortality and sepsis in adult inpatients.

Methods

PubMed, MEDLINE, EMBASE, Scopus, Web of Science, Science Direct, CINAHL, Open Grey, Grey Literature Report, and the Clinical Trials registry were searched using CRP and qSOFA search terms. Title, abstract, and full-text screening were performed by two independent reviewers using pre-determined eligibility criteria, followed by data extraction and a risk of bias assessment using the Quality Assessment tool for Diagnostic Accuracy Studies 2 (QUADAS-2). Disagreements were settled through discussion and consultation with a third reviewer.

Results

Four retrospective studies with a total of 2070 patients were included in this review. Adding CRP to qSOFA improved the Area Under the Receiver Operating Characteristic Curve up to 9.7% for predicting mortality and by 14.9% for identifying sepsis. The sensitivity and specificity of the combined score for mortality prediction were available in two studies. CRP improved the sensitivity of qSOFA by 43% and 71% while only decreasing the specificity by 12% and 7%, respectively. A meta-analysis was not performed due to study heterogeneity.

Conclusion

This comprehensive review provided initial evidence that combining CRP with qSOFA may improve the accuracy of qSOFA alone in identifying sepsis or patients at risk of dying in hospital. The combined tool demonstrated the potential to improve patient outcomes, with implications for low-resource settings given its simplicity and low-cost.

Preoperative risk score (PreopScore) to predict overall survival after resection for hepatocellular carcinoma

BACKGROUND

This study aimed to develop a holistic risk score incorporating preoperative tumor, liver, nutritional, and inflammatory markers to predict overall survival (OS) after hepatectomy for hepatocellular carcinoma (HCC).

METHODS

Patients who underwent curative-intent surgery for HCC between 2000 and 2020 were identified using an international multi-institutional database. Preoperative predictors associated with OS were selected and a prognostic risk score model (PreopScore) was developed and validated using cross-validation.

RESULTS

A total of 1676 patients were included. On multivariable analysis, preoperative parameters associated with OS included α-feto protein (hazard ratio [HR]1.17, 95%CI 1.03-1.34), neutrophil-to-lymphocyte ratio (HR2.62, 95%CI 1.30-5.30), albumin (HR0.49, 95%CI 0.34-0.70), gamma-glutamyl transpeptidase (HR1.00, 95%CI 1.00-1.00), as well as vascular involvement (HR3.52, 95%CI 2.10-5.89) and tumor burden score (medium, HR3.49, 95%CI 1.62-7.58; high, HR3.21, 95%CI 1.40-7.35) on preoperative imaging. A weighted PreopScore was devised and made available online (https://yutaka-endo.shinyapps.io/PrepoScore_Shiny/). Patients with a PreopScore 0-2, 2-3.5, and >3.5 had incrementally worse 5-year OS of 85.8%, 70.7%, and 52.4%, respectively (p < 0.001). The c-index of the test and validation cohort were 0.75 and 0.71, respectively. The PreopScore outperformed individual parameters and previous HCC staging systems.

DISCUSSION

The PreopScore can be used as a better guide to preoperatively identify patients and individualize pre-/post-operative strategies.

TAC score better predicts survival than the BCLC following resection of hepatocellular carcinoma

BACKGROUND

Heterogeneity in hepatocellular carcinoma (HCC) still exists within the Barcelona clinic liver cancer (BCLC) subcategories. We developed a simple model to better discriminate and predict prognosis following resection.

METHODS

Patients who underwent curative-intent resection for HCC were identified from a multi-institutional database. Predictive factors of survival were identified to develop TAC (tumor burden score [TBS], alpha-fetoprotein [AFP], Child-Pugh CP]) score.

RESULTS

Among 1435 patients, median TBS was 5.1 (interquartile range [IQR]: 3.2-8.1), median AFP was 18.3 ng/ml (IQR 4.0-362.5), and 1391 (96.9%) patients were classified as CP-A. Factors associated with overall survival (OS) included TBS (low: referent; medium: HR 2.26, 95% CI: 1.73-2.96; high: HR = 3.35, 95% CI: 2.22-5.07), AFP (<400 ng/ml: referent; >400 ng/ml: HR = 1.56, 95% CI: 1.27-1.92), and CP (A: referent; B: HR = 1.81, 95% CI: 1.12-2.92) (all p < 0.05). A simplified risk score demonstrated superior concordance index, Akaike information criteria, homogeneity, and area under the curve versus BCLC (0.620 vs. 0.541; 5484.655 vs. 5536.454; 60.099 vs. 16.194; 0.62 vs. 0.55, respectively), and further stratified patients within BCLC groups relative to OS (BCLC 0, very low: 86.8%, low: 47.8%) (BCLC A, very low: 79.7%, low: 68.1%, medium: 52.5%, high: 35.6%) (BCLC B, low: 59.8%, medium: 43.7%, high: N/A).

CONCLUSION

TAC is a simple, holistic score that consistently outperformed BCLC relative to discrimination power and prognostication following resection of HCC.

TBS-Based Preoperative Score to Predict Non-transplantable Recurrence and Identify Candidates for Upfront Resection Versus Transplantation for Hepatocellular Carcinoma

BACKGROUND

Recurrence following liver resection (LR) for hepatocellular carcinoma (HCC) can be as high as 50-70%. While salvage liver transplantation may be feasible, patients may develop a non-transplantable recurrence (NTR) (recurrence beyond Milan criteria). We sought to identify preoperative risk factors to predict NTR after resection.

PATIENTS AND METHODS

Patients who underwent curative-intent LR for HCC were identified from a multi-institutional database. Preoperative factors associated with NTR were identified and a risk score model (NTR score) was developed and validated.

RESULTS

Among 1620 patients, 842 (52.0%) developed recurrence; among patients with recurrence, NTR occurred in 341 (40.5%) with a median recurrence-free survival (RFS) of 30 months (24.7-35.3 months). On multivariable analysis, factors associated with NTR included alpha fetoprotein (AFP) > 400 ng/mL [hazard ratio (HR) 1.71, 95% confidence interval (CI) 1.33-2.19], albumin-bilirubin grade (ALBI) (referent low, medium ALBI: HR 1.41, 95% CI 1.10-1.81, high ALBI: HR 2.47, 95% CI 0.91-6.68), and tumor burden score (TBS) (referent low, high TBS: HR 2.55, 95% CI, 1.99-3.28). A simplified TBS-based NTR score was developed using the β-coefficients of each factor (C-index 0.68, 95% CI 0.65-0.71). Higher NTR score was associated with incrementally worse 5-year RFS (low 44.8%, medium 37.5%, high 24.5%) [area under the curve (AUC) 0.59] and increased incidence of NTR (low 13.7%, medium 25.4%, high 38.2%) (AUC 0.65) (both p < 0.001). Moreover, higher NTR score was associated with higher risk of extrahepatic recurrence (low 11.3%, medium 28.8%, high 37.5%) (p < 0.001).

CONCLUSION

NTR following curative-intent resection of HCC occurred in one in five patients. A simple TBS-based NTR score accurately predicted the risk of NTR and may help identify candidates for upfront resection versus transplantation.

Persistent mutation burden drives sustained anti-tumor immune responses

Tumor mutation burden is an imperfect proxy of tumor foreignness and has therefore failed to consistently demonstrate clinical utility in predicting responses in the context of immunotherapy. We evaluated mutations in regions of the genome that are unlikely to undergo loss in a pan-cancer analysis across 31 tumor types (n = 9,242) and eight immunotherapy-treated cohorts of patients with non-small-cell lung cancer, melanoma, mesothelioma, and head and neck cancer (n = 524). We discovered that mutations in single-copy regions and those present in multiple copies per cell constitute a persistent tumor mutation burden (pTMB) which is linked with therapeutic response to immune checkpoint blockade. Persistent mutations were retained in the context of tumor evolution under selective pressure of immunotherapy and tumors with a high pTMB content were characterized by a more inflamed tumor microenvironment. pTMB imposes an evolutionary bottleneck that cancer cells cannot overcome and may thus drive sustained immunologic tumor control in the context of immunotherapy.

Application of hazard functions to investigate recurrence after curative-intent resection for hepatocellular carcinoma

BACKGROUND

Defining patterns and risk of recurrence can help inform surveillance strategies and patient counselling. We sought to characterize peak hazard rates (pHR) and peak time of recurrence among patients who underwent resection of hepatocellular carcinoma (HCC).

METHODS

1434 patients who underwent curative-intent resection of HCC were identified from a multi-institutional database. Hazard, patterns, and peak rates of recurrence were characterized.

RESULTS

The overall hazard of recurrence peaked at 2.4 months (pHR: 0.0384), yet varied markedly. The incidence of recurrence increased with Barcelona Clinic Liver Cancer (BCLC) stage 0 (29%), A (54%), and B (64%). While the hazard function curve for BCLC 0 patients was relatively flat (pHR: <0.0177), BCLC A patients recurred with a peak at 2.4 months (pHR: 0.0365). Patients with BCLC B had a bimodal recurrence with a peak rate at 4.2 months (pHR: 0.0565) and another at 22.8 months. The incidence of recurrence also varied according to AFP level (≤400 ng/mL: 52.6% vs. >400 ng/mL: 36.3%) and Tumor Burden Score (low: 73.7% vs. medium: 50.6% vs. high: 24.2%) (both p < 0.001).

CONCLUSION

Recurrence hazard rates for HCC varied substantially relative to both time and intensity/peak rates. TBS and AFP markedly impacted patterns of hazard risk of recurrence.

A Novel Online Calculator to Predict Risk of Microvascular Invasion in the Preoperative Setting for Hepatocellular Carcinoma Patients Undergoing Curative-Intent Surgery

BACKGROUND

The presence of microvascular invasion (MVI) has been highlighted as an important determinant of hepatocellular carcinoma (HCC) prognosis. We sought to build and validate a novel model to predict MVI in the preoperative setting.

METHODS

Patients who underwent curative-intent surgery for HCC between 2000 and 2020 were identified using a multi-institutional database. Preoperative predictive models for MVI were built, validated, and used to develop a web-based calculator.

RESULTS

Among 689 patients, MVI was observed in 323 patients (46.9%). On multivariate analysis in the test cohort, preoperative parameters associated with MVI included α-fetoprotein (AFP; odds ratio [OR] 1.50, 95% confidence interval [CI] 1.23-1.83), imaging tumor burden score (TBS; hazard ratio [HR] 1.11, 95% CI 1.04-1.18), and neutrophil-to-lymphocyte ratio (NLR; OR 1.18, 95% CI 1.03-1.35). An online calculator to predict MVI was developed based on the weighted β-coefficients of these three variables ( https://yutaka-endo.shinyapps.io/MVIrisk/ ). The c-index of the test and validation cohorts was 0.71 and 0.72, respectively. Patients with a high risk of MVI had worse disease-free survival (DFS) and overall survival (OS) compared with low-risk MVI patients (3-year DFS: 33.0% vs. 51.9%, p < 0.001; 5-year OS: 44.2% vs. 64.8%, p < 0.001). DFS was worse among patients who underwent an R1 versus R0 resection among those patients at high risk of MVI (R0 vs. R1 resection: 3-year DFS, 36.3% vs. 16.1%, p = 0.002). In contrast, DFS was comparable among patients at low risk of MVI regardless of margin status (R0 vs. R1 resection: 3-year DFS, 52.9% vs. 47.3%, p = 0.16).

CONCLUSION

Preoperative assessment of MVI using the online tool demonstrated very good accuracy to predict MVI.

Variations in Textbook Oncologic Outcomes After Curative-Intent Resection: Early Versus Intermediate Hepatocellular Carcinoma Based on Barcelona Clinic Liver Cancer Criteria and Child-Pugh Classification

BACKGROUND

The impact of early versus intermediate hepatocellular carcinoma (HCC) on short-term "optimal" outcomes remains ill-defined. This study sought to define the incidence of textbook oncologic outcomes (TOO), as well as to identify factors associated with TOO among patients with early versus intermediate HCC.

METHODS

Patients who underwent curative-intent liver resection for HCC (1998-2020) were identified from a multi-institutional database. Textbook oncologic outcome (TOO) was defined as negative surgical margins, no return to the operating room, no extended hospital stay, no severe complications, and no 90-day mortality or readmission. Patients were stratified as early HCC (BCLC 0 or BCLC A/Child-Pugh A) or intermediate HCC (BCLC A/Child-Pugh B or BCLC B). Multivariate logistic regression analysis was used to assess factors associated with TOO.

RESULTS

Among 1383 patients, the overall incidence of TOO was 69.0%. Patients with intermediate HCC were less likely to achieve a TOO (early [71.6 %] vs. intermediate [60.1%]; p < 0.001). On multivariate analysis, factors associated with decreased odds of a TOO were high tumor burden (odds ratio [OR], 0.57; 95% confidence interval [CI], 0.33-1.00), high aspartate transaminase-platelet ratio index (APRI) (OR, 0.46; 95% CI, 0.30-0.70), Charlson Comorbidity Index (CCI) greater than 3 (OR, 0.67; 95% CI, 0.49-0.91), major liver resection (OR, 0.68; 95% CI, 0.52-0.90), and intermediate HCC (OR, 0.68; 95% CI, 0.50-0.93) (all p < 0.05). Notably, although high APRI, CCI greater than 3, and major liver resection contributed to lower odds of a TOO in early HCC, the only factor that adversely impacted TOO in intermediate HCC was high tumor burden.

CONCLUSIONS

Patients with intermediate HCC and early HCC patients with liver dysfunction, comorbidities, or an extensive resection were less likely to achieve an "optimal" postoperative outcome.

Liquid biopsy approaches to capture tumor evolution and clinical outcomes during cancer immunotherapy

Circulating cell-free tumor DNA (ctDNA) can serve as a real-time biomarker of tumor burden and provide unique insights into the evolving molecular landscape of cancers under the selective pressure of immunotherapy. Tracking the landscape of genomic alterations detected in ctDNA may reveal the clonal architecture of the metastatic cascade and thus improve our understanding of the molecular wiring of therapeutic responses. While liquid biopsies may provide a rapid and accurate evaluation of tumor burden dynamics during immunotherapy, the complexity of antitumor immune responses is not fully captured through single-feature ctDNA analyses. This underscores a need for integrative studies modeling the tumor and the immune compartment to understand the kinetics of tumor clearance in association with the quality of antitumor immune responses. Clinical applications of ctDNA testing in patients treated with immune checkpoint inhibitors have shown both predictive and prognostic value through the detection of genomic biomarkers, such as tumor mutational burden and microsatellite instability, as well as allowing for real-time monitoring of circulating tumor burden and the assessment of early on-therapy responses. These efforts highlight the emerging role of liquid biopsies in selecting patients for cancer immunotherapy, monitoring therapeutic efficacy, determining the optimal duration of treatment and ultimately guiding treatment selection and sequencing. The clinical translation of liquid biopsies is propelled by the increasing number of ctDNA-directed interventional clinical trials in the immuno-oncology space, signifying a critical step towards implementation of liquid biopsies in precision immuno-oncology.

Reducing unplanned general surgical readmissions: a review of the Australian and New Zealand National Surgical Quality Improvement Program Database

BACKGROUND

Unplanned surgical readmissions are an important indicator of quality care and are a key focus of improvement programs. The aims of this study were to evaluate the factors that lead to unplanned hospital readmissions in patients undergoing general surgical procedures and to identify preventable readmissions.

METHODS

A retrospective review of the American College of Surgeons National Surgical Quality Improvement Program database from 2016 to 2020 at a tertiary hospital was conducted to identify patients undergoing a general surgical procedure. Various perioperative parameters were studied to identify risk factors and reasons for unplanned readmission. Preventable readmissions were identified.

RESULTS

A total of 3069 patients underwent a general surgical procedure. Of these, the overall unplanned readmission rate was 8.8% (n = 247). The most common reason for readmission was associated with surgical site infections (n = 112, 44.3%) followed by pain (n = 50, 20.2%), with over 45% deemed as preventable readmissions. Factors associated with increased risk of readmission included older age, longer index length of stay, prolonged operative time, elective procedures, higher ASA score and contaminated procedures.

CONCLUSION

Unplanned readmissions are more likely to occur in patients who develop postoperative complications. Understanding factors associated with readmissions may facilitate targeted quality improvement projects that reduce hospital readmission after surgery.

A comprehensive preoperative predictive score for post-hepatectomy liver failure after hepatocellular carcinoma resection based on patient comorbidities, tumor burden, and liver function: the CTF score

BACKGROUND

Post-hepatectomy liver failure (PHLF) is a dreaded complication following liver resection for hepatocellular carcinoma (HCC) with a high mortality rate. We sought to develop a score based on preoperative factors to predict PHLF.

METHODS

Patients who underwent resection for HCC between 2000 and 2020 were identified from an international multi-institutional database. Factors associated with PHLF were identified and used to develop a preoperative comorbidity-tumor burden-liver function (CTF) predictive score.

RESULTS

Among 1785 patients, 106 (5.9%) experienced PHLF. On multivariate analysis, several factors were associated with PHLF including high Charlson comorbidity index (CCI ≥ 5) (OR 2.80, 95%CI, 1.08-7.26), albumin-bilirubin (ALBI) (OR 1.99, 95%CI, 1.10-3.56), and tumor burden score (TBS) (OR 1.06, 95%CI, 1.02-1.11) (all p < 0.05). Using the beta-coefficients of these variables, a weighted predictive score was developed and made available online ( https://alaimolaura.shinyapps.io/PHLFriskCalculator/ ). The CTF score (c-index = 0.67) performed better than Child-Pugh score (CPS) (c-index = 0.53) or Barcelona clinic liver cancer system (BCLC) (c-index = 0.57) to predict PHLF. A high CTF score was also an independent adverse prognostic factor for survival (HR 1.61, 95%CI, 1.12-2.30) and recurrence (HR 1.36, 95%CI, 1.08-1.71) (both p = 0.01).

CONCLUSION

Roughly 1 in 20 patients experienced PHLF following resection of HCC. Patient (i.e., CCI), tumor (i.e., TBS), and liver function (i.e., ALBI) factors were associated with risk of PHLF. These preoperative factors were incorporated into a novel CTF tool that was made available online, which outperformed other previously proposed tools.

Tumor Burden Score and Serum Alpha-fetoprotein Subclassify Intermediate-Stage Hepatocellular Carcinoma

BACKGROUND

Resection of Barcelona Clinic Liver Cancer (BCLC) intermediate-stage hepatocellular carcinoma (HCC) remains controversial. While not recommended by the BCLC algorithm, some patients may indeed benefit from hepatectomy. We sought to identify that subset of patients who might derive long-term survival benefit from resection.

METHODS

Intermediate-stage HCC patients who underwent curative-intent resection were identified from an international multi-institutional database. Factors associated with long-term prognosis were identified using multivariate analysis and a risk score was developed and assessed.

RESULTS

Among 194 patients, most individuals had two tumors (n = 123, 63.4%) with a median size of 6.0 cm (IQR, 4.0-8.4) for a median tumor burden score (TBS) of 6.5 (IQR, 5.0-9.1); median alpha-fetoprotein (AFP) was 23.9 ng/mL (IQR, 5.0-503.2), and median overall survival (OS) was 69 months (IAR, 60.7-77.3). Factors associated with OS included AFP (referent ≤ 20 ng/mL, > 20 ng/mL: HR 1.78 95%CI, 1.09-2.89) and TBS (referent TBS ≤ 8.0, TBS > 8.0: HR 1.72 95%CI, 1.07-2.75). While 71 (36.6%) patients had neither risk factor, 79 (40.7%) and 44 (22.7%) had 1 or 2, respectively. A simplified score stratified patients relative to recurrence-free survival (RFS) (0: 33.6% vs. 1: 18.0% vs. 2: 14.7%) (AUC 0.60) and recurrence time (i.e., < 6 months after surgery) (0: 21.3% vs. 1: 43.1% vs. 2: 68.6%) (AUC 0.69) (both p < 0.001). Of note, a higher score was also associated with incrementally worse 5-year OS (0: 68.1% vs. 1: 61.0% vs. 2: 29.9%) (AUC 0.62) (p < 0.001).

CONCLUSION

Long-term OS and RFS outcomes varied considerably. Using a simple risk score, patients with low AFP and low TBS were identified as the subset of individuals most likely to benefit from resection.

Does lactate enhance the prognostic accuracy of the quick Sequential Organ Failure Assessment for adult patients with sepsis? A systematic review

OBJECTIVES

To investigate whether adding lactate to the quick Sequential (sepsis-related) Organ Failure Assessment (qSOFA) improves the prediction of mortality in adult hospital patients, compared with qSOFA alone.

DESIGN

Systematic review in accordance with Preferred Reporting Items for a Systematic Review and Meta-analysis of Diagnostic Test Accuracy Studies guidelines.

DATA SOURCES

Embase, Medline, PubMed, SCOPUS, Web of Science, CINAHL and Open Grey databases were searched in November 2020.

ELIGIBILITY CRITERIA

Original research studies published after 2016 comparing qSOFA in combination with lactate (LqSOFA) with qSOFA alone in adult patients with sepsis in hospital. The language was restricted to English.

DATA EXTRACTION AND SYNTHESIS

Title and abstract screening, full-text screening, data extraction and quality assessment (using Quality Assessment of Diagnostic Accuracy Studies-2) were conducted independently by two reviewers. Extracted data were collected into tables and diagnostic test accuracy was compared between the two tests.

RESULTS

We identified 1621 studies, of which 11 met our inclusion criteria. Overall, there was a low risk of bias across all studies. The area under the receiver operating characteristic (AUROC) curve for qSOFA was improved by the addition of lactate in 9 of the 10 studies reporting it. Sensitivity was increased in three of seven studies that reported it. Specificity was increased in four of seven studies that reported it. Of the six studies set exclusively within the emergency department, five published AUROCs, all of which reported an increase following the addition of lactate. Sensitivity and specificity results varied throughout the included studies. Due to insufficient data and heterogeneity of studies, a meta-analysis was not performed.

CONCLUSIONS

LqSOFA is an effective tool for identifying mortality risk both in adult inpatients with sepsis and those in the emergency department. LqSOFA increases AUROC over qSOFA alone, particularly within the emergency department. However, further original research is required to provide a stronger base of evidence in lactate measurement timing, as well as prospective trials to strengthen evidence and reduce bias.

PROSPERO REGISTRATION NUMBER

CRD42020207648.

Impact of tumor burden score on timing and patterns of recurrence after curative-intent resection of hepatocellular carcinoma

BACKGROUND

The ability to predict the incidence, timing, and site of recurrence can be beneficial to select surgical candidates and inform appropriate postoperative surveillance. We sought to identify factors associated with risk and timing of recurrence after resection of hepatocellular carcinoma based on differences in tumor burden score.

METHODS

Patients who underwent curative-intent liver resection for hepatocellular carcinoma between 2000 and 2020 were identified from an international multi-institutional database. The incidence, timing, and pattern of recurrence was examined relative to traditional clinicopathological factors, as well as tumor burden score using hazard rates and multivariable analysis.

RESULTS

Among 1,994 patients (tumor burden score, low: n = 511, 25.6% vs medium: n = 1,286, 64.5% vs high: n = 197, 9.9%), the incidence of recurrence at 5 years was 50.4% (95% confidence interval 47.9-53.0); risk of recurrence varied relative to hepatocellular carcinoma tumor burden score (low: 36.0% vs medium: 54.4% vs high: 62.5%, P < .001). Although intrahepatic recurrence was much more common in low tumor burden score (low: n = 106, 84.1% vs medium: n = 335, 71.7% vs high: n = 48, 56.5%; P < .001), extrahepatic recurrence was more common in high tumor burden score (low: n = 18, 14.3% vs medium: n = 121, 25.9% vs high: n = 37, 43.5%; P < .001). The peak hazard rate for intrahepatic recurrence among patients with a high tumor burden score was almost double the peak hazard noted among patients with a low tumor burden score (low: 0.047, 42.0 months vs medium: 0.051, 6.6 months vs high: 0.094, 15.0 months). Of note, the patients with high tumor burden score were also more likely to recur earlier (≤24 months) (low: n = 227, 44.4% vs medium: n = 686, 53.3% vs high: n = 144, 73.1%) with multiple tumors (low: n = 50, 36.5% vs medium: n = 271, 56.1% vs high: n = 52, 70.3%) and larger lesions (low: 1.8 [interquartile range 1.2-3.0] cm vs medium: 2.0 [interquartile range 1.3-3.0] cm vs high: 2.5 [interquartile range 1.6-4.4] cm) (all P < .001). On multivariable analysis, high tumor burden score remained independently associated with risk of recurrence (referent, low; medium: hazard ratio = 1.49 [95% confidence interval 1.19-1.88], P = .001; high: hazard ratio = 1.95 [95% confidence interval 1.41-2.69]; P < .001].

CONCLUSION

Tumor burden score was independently associated with higher risk of recurrence. Patients who underwent resection of high tumor burden score lesions were more likely to recur early with multiple tumors and at an extrahepatic site. Tumor burden score is an important tool in assessing risk, timing, and pattern of recurrence after resection of hepatocellular carcinoma.

Influence of Multiple Music Styles and Composition Styles on College Students' Mental Health

The purpose is to reduce students' psychological pressure and improve their quality of study and life. Here, 400 language-impaired students in the public elective psychology course at Northwestern University and the undergraduate psychology class at Xi'an Foreign Studies University in the 2018-2019 academic year are randomly selected as the research objects for this music psychology experiment. The students were divided into different experimental groups using the Questionnaire Survey (QS) method to analyze the students' psychological reactions to Baroque, classical, and romantic music styles. Then, it further discusses the students' emotional response and audiovisual synaesthesia, as well as their recognition and choice of music style. The results show that there are significant differences in the same emotional response intensity of the subjects to different styles of music creation. The music expression is consistent with the actual feelings of the subjects. The tonality and color density of audiovisual synaesthesia vary with the style of music creation. Different music creation styles generate different associations in students' minds, thus showing different psychological reactions. The QS results indicate that soft and soothing music can relieve students' learning pressure most, while music with a strong sense of rhythm and vitality has no significant effect. Therefore, different music creation styles affect students' learning pressure differently. This work discusses the influence of different music creation styles on the mental health of contemporary college students and provides a reference for music therapy to relieve students' learning pressure in the future.

Peripheral blood immune cell dynamics reflect antitumor immune responses and predict clinical response to immunotherapy

BACKGROUND

Despite treatment advancements with immunotherapy, our understanding of response relies on tissue-based, static tumor features such as tumor mutation burden (TMB) and programmed death-ligand 1 (PD-L1) expression. These approaches are limited in capturing the plasticity of tumor-immune system interactions under selective pressure of immune checkpoint blockade and predicting therapeutic response and long-term outcomes. Here, we investigate the relationship between serial assessment of peripheral blood cell counts and tumor burden dynamics in the context of an evolving tumor ecosystem during immune checkpoint blockade.

METHODS

Using machine learning, we integrated dynamics in peripheral blood immune cell subsets, including neutrophil-lymphocyte ratio (NLR), from 239 patients with metastatic non-small cell lung cancer (NSCLC) and predicted clinical outcome with immune checkpoint blockade. We then sought to interpret NLR dynamics in the context of transcriptomic and T cell repertoire trajectories for 26 patients with early stage NSCLC who received neoadjuvant immune checkpoint blockade. We further determined the relationship between NLR dynamics, pathologic response and circulating tumor DNA (ctDNA) clearance.

RESULTS

Integrated dynamics of peripheral blood cell counts, predominantly NLR dynamics and changes in eosinophil levels, predicted clinical outcome, outperforming both TMB and PD-L1 expression. As early changes in NLR were a key predictor of response, we linked NLR dynamics with serial RNA sequencing deconvolution and T cell receptor sequencing to investigate differential tumor microenvironment reshaping during therapy for patients with reduction in peripheral NLR. Reductions in NLR were associated with induction of interferon-γ responses driving the expression of antigen presentation and proinflammatory gene sets coupled with reshaping of the intratumoral T cell repertoire. In addition, NLR dynamics reflected tumor regression assessed by pathological responses and complemented ctDNA kinetics in predicting long-term outcome. Elevated peripheral eosinophil levels during immune checkpoint blockade were correlated with therapeutic response in both metastatic and early stage cohorts.

CONCLUSIONS

Our findings suggest that early dynamics in peripheral blood immune cell subsets reflect changes in the tumor microenvironment and capture antitumor immune responses, ultimately reflecting clinical outcomes with immune checkpoint blockade.

Non-transplantable Recurrence After Resection for Transplantable Hepatocellular Carcinoma: Implication for Upfront Treatment Choice

OBJECTIVES

To identify the preoperative risk factors for prediction of non-transplantable recurrence (NTR) after tumor resection for early-stage hepatocellular carcinoma (HCC) to assist in patient selection relative to upfront liver resection (LR) versus liver transplantation (LT).

METHODS

Patients who underwent curative resection for transplantable HCC and chronic liver disease were identified from an international multi-institutional database. NTR was defined as recurrence beyond the Milan or UCSF criteria, and the preoperative risk factors of NTR were investigated.

RESULTS

Among 293 patients with transplantable HCC within Milan criteria and 320 within UCSF criteria, 113 (38.6%) and 131 (40.9%) patients developed tumor recurrence, respectively. Among patients who recurred, NTR was present in 32 (28.3%) patients within Milan and 35 (26.7%) within UCSF criteria. When either Milan or UCSF criteria was adopted, three preoperative risk factors including liver cirrhosis, tumor size > 3 cm, and multiple lesions were consistently identified as risk factors associated with NTR after curative resection. By summing up the three factors, a scoring model was established and the incidence of NTR among patients with 0, 1 or ≥ 2 risk factors incrementally increased from 4.5%, 13.3% to 20.5% when Milan criteria was used, and from 4.5%, 12.4% to 33.9% when UCSF criteria was adopted. The model demonstrated very good discriminatory power on internal validation (n = 5,000) (c-index 0.689 for Milan criteria, and 0.715 for UCSF criteria).

CONCLUSIONS

Whereas surgical resection may be optimal first-line treatment for patients with no or one risk factor, patients with ≥ 2 risk factors should be considered for upfront liver transplantation.

The Role of Targeted Versus Standard Antibiotic Prophylaxis in Pancreatoduodenectomy in Reducing Postoperative Infectious Complications: A Systematic Review and Meta-analysis

INTRODUCTION

Infectious complications are common after pancreatoduodenectomy, which in turn are associated with preoperative biliary drainage. Current guidelines recommend a first-generation cephalosporin as perioperative antibiotic prophylaxis. However, some studies support the use of targeted antibiotics. The aim of this systematic review and meta-analysis is to evaluate the role of prophylactic targeted antibiotics compared to standard antibiotics in reducing postoperative infections after pancreatoduodenectomy.

METHODS

A search from MEDLINE, EMBASE, and Cochrane library from 1946 to July 2020 was conducted. Studies were included if they compared targeted antibiotics with standard perioperative antibiotics while including outcome data on surgical site infections (SSI). Targeted therapy was defined as perioperative antibiotics targeting organisms prevalent in bile instrumentation or by culture data obtained from the patient or institution. Outcomes assessed were the rate of SSIs and their microbiology profile. Analyses included demographic data, perioperative antibiotics, postoperative outcomes including microbiology data, and meta-analysis was performed where applicable.

RESULTS

Seven studies were included, with a total of 849 patients undergoing pancreatoduodenectomy. Targeted antibiotics were associated with a significantly lower rate of postoperative SSI compared to standard antibiotic therapy [21.1% vs 41.9%; risk ratios (RR) 0.55, 95% confidence interval 0.37-0.81]. Wound/incisional site infections and organ space infections were lower in patients receiving targeted antibiotic prophylaxis (RR 0.33, P = 0.0002 and RR 0.54, P = 0.0004, respectively). Enterococcus species were the most common bacteria reported.

CONCLUSION

There was a significant reduction in overall SSI rates when targeted antibiotics was used. Current standard antibiotic prophylaxis is inadequate in covering microbes prevalent in postoperative infections developing after pancreatoduodenectomy.

296 A comprehensive clinical and genomic characterization of long-term responders receiving immune checkpoint blockade for metastatic non-small cell lung cancer

Background

Five-year survival analyses of patients receiving immune checkpoint inhibitors (ICIs) for metastatic non-small cell lung cancer (NSCLC) have demonstrated continued clinical benefit compared to chemotherapy.1 2 Our study aims at understanding and defining the unique clinical and genomic underpinnings of a durable response to ICI in advanced NSCLC.

Methods

We conducted a retrospective case-control study using information abstracted from a Johns Hopkins IRB-approved database of NSCLC patients treated with an ICI-containing regimen. We defined long-term responders (LR) as patients who have achieved an overall survival (OS) of at least 3 years. We identified a comparison arm (C) of patients whose OS was less than a year. Univariate and multivariate analyses of the clinical and molecular characteristics were conducted between the LR and C groups using IBM Statistical Package for Social Sciences version 25.

Results

A cohort of 89 patients were included; 41 patients as LR and 48 as C. Mean duration of ICI was 21.6 months and 3.5 months for LR and C, respectively. On univariate analysis, there was no statistically significant difference in age, sex, race, histology or treatment characteristics between arms. However, ECOG performance status (PS) of 2 (p=0.011) and evidence of liver metastases were independently associated with a shorter response to ICI (p=0.012). Increased PD-L1 expression was significantly associated with likelihood of LR status (OR= 1.018, p=0.027). 65.9% (n=27) of LR patients developed an immune-related adverse event (irAE), of which 20 patients required discontinuation of therapy. In the C arm, 16.7% (n=8) of patients developed an irAE of which 4 patients required discontinuation. On multivariate analysis, including age, sex, race, ethnicity, smoking status, BMI, PS, liver and brain metastases as well as the presence of common oncogenic molecular alterations, PS of < 2 was statistically significantly associated with an OS ≥3 years (OR=16.7, p= 0.017). Molecular profiling was completed in 53 patients (LR=29, C=24). Common molecular alterations were identified in 28 out of 53 patients (LR=16, C=12). KRAS mutation was assessed in 34 patients (LR=16, C=18) and was associated with LR status versus C (Fisher’s exact test value p=0.0386).

Conclusions

Our retrospective study assessing multiple clinical and molecular determinants of patients with long-term response to immune checkpoint blockade, identified PS at diagnosis and KRAS mutation status to be associated with long-term response. Current efforts are ongoing to interrogate more deeply molecular features of LR, as well as their relationship to clinical aspects of a sustained benefit from ICI in NSCLC.

References

Borghaei H, et al. Five-year outcomes from the randomized, phase III trials checkMate 017 and 057: nivolumab versus docetaxel in previously treated non–small-cell lung cancer. Journal of Clinical Oncology 0, JCO.20.01605, doi:10.1200/jco.20.01605 (2021)

Reck M, et al. Five-year outcomes with pembrolizumab versus chemotherapy for metastatic non-small-cell lung cancer with PD-L1 tumor proportion score ≥ 50. J Clin Oncol 39:2339–2349, doi:10.1200/jco.21.00174 (2021)

Ethics Approval

The retrospective case-control study has obtained ethics approval from the Institutional Review Board at the Johns Hopkins School of Medicine.

Climate modelling and structural stability

Climate modelling plays a crucial role for understanding and addressing the climate challenge, in terms of both mitigation and adaptation. It is therefore of central importance to understand to what extent climate models are adequate for relevant purposes, such as providing certain kinds of climate change projections in view of decision-making. In this perspective, the issue of the stability of climate models under small relevant perturbations in their structure (or small relevant 'structural model errors' with respect to the target system) seems particularly important. Within this framework, a debate has emerged in the philosophy of science literature about the relevance for climate modelling of the mathematical notion of structural stability. This paper adresses several important foundational and epistemological questions that arise in this context, in particular about the the role of abstract mathematical considerations of a qualitative nature (in some precise, topological sense) for concrete modelling projects with mainly quantitative purposes.