Somatic Mutations Increase Hepatic Clonal Fitness and Regeneration in Chronic Liver Disease.

Normal tissues accumulate genetic changes with age, but it is unknown if somatic mutations promote clonal expansion of non-malignant cells in the setting of chronic degenerative diseases. Exome sequencing of diseased liver samples from 82 patients revealed a complex mutational landscape in cirrhosis. Additional ultra-deep sequencing identified recurrent mutations in PKD1, PPARGC1B, KMT2D, and ARID1A. The number and size of mutant clones increased as a function of fibrosis stage and tissue damage. To interrogate the functional impact of mutated genes, a pooled in vivo CRISPR screening approach was established. In agreement with sequencing results, examination of 147 genes again revealed that loss of Pkd1, Kmt2d, and Arid1a promoted clonal expansion. Conditional heterozygous deletion of these genes in mice was also hepatoprotective in injury assays. Pre-malignant somatic alterations are often viewed through the lens of cancer, but we show that mutations can promote regeneration, likely independent of carcinogenesis.

Defining Volume Targets for Regionalization of Pancreaticoduodenectomy, Esophagectomy, and Major Lung Resection Centers to Improve Oncologic and Surgical Outcomes.

BACKGROUND: Performance of complex cancer surgeries at high-volume (HV) centers has been shown to reduce operative mortality. However, the case volume threshold that should be used to define HV centers is unknown. In this study, we determined thresholds to define HV pancreaticoduodenectomy, esophagectomy, and major lung resection centers based on clinical parameters. Then, we assessed the association of hospital volume with oncologic outcomes and overall survival. METHODS: We identified adult NCDB patients undergoing pancreaticoduodenectomy, esophagectomy, and major lung resections between 2004 and 2015. Multivariable models with restricted cubic splines were built to predict 5-year overall survival for each surgery group according to average yearly case volume, adjusting for demographic and clinicopathologic factors. The change point procedure was then used to identify volume cut-points for each surgery type. RESULTS: We identified the following thresholds to define HV status: 25 cases/year for pancreaticoduodenectomy; 18 cases/year for esophagectomy; and 54 cases/year for major lung resections. For all surgery types, treatment at a HV center was associated with an increased likelihood of R0 resection and adequate lymph node evaluation. HV centers had significantly decreased 30- and 90-day, postoperative mortality after adjusting for age, sex, race, comorbidities, histology, and stage. An overall survival benefit also was observed for patients undergoing resections at HV centers. CONCLUSIONS: Using novel methodology, our study identified volume thresholds for HV pancreaticoduodenectomy, esophagectomy, and major lung resection centers that were associated with improved oncologic outcomes and overall survival. These definitions of HV centers should be considered when evaluating regionalization of complex cancer care.

Cost Analysis and Financial Implications of a Peritoneal Surface Malignancy Program in the USA.

BACKGROUND: We aimed to describe the financial implications of cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) in the USA. MATERIALS AND METHODS: We conducted a retrospective cost analysis of 100 CRS/HIPEC procedures to examine the impact of patient and procedural factors on hospital costs and reimbursement. A comparison of surgeons' work relative value units (wRVUs) between CRS/HIPEC and a representative sample of complex surgical oncology procedures was made to assess the physicians' compensation rate. Univariable and multivariable backward logistic regression was used to analyze the association between perioperative variables and high direct cost (HDCs). RESULTS: The median direct cost per CRS/HIPEC procedure was US $44,770. The median hospital reimbursement was US $43,066, while professional reimbursement was US $8608, resulting in a positive contribution margin of US $7493/procedure. However, the contribution margin significantly varied with the payer mix. Privately insured patients had a positive median contribution margin of US $23,033, whereas Medicare-insured patients had a negative contribution margin of US $13,034. Length of stay (LOS) had the most significant association with HDC, and major complications had the most significant association with LOS. Finally, CRS/HIPEC procedures generated a median of 13 wRVU/h, which is significantly lower than the wRVU/h generated by open pancreatoduodenectomies, open gastrectomies, and hepatectomies. However, higher operation complexity and multiple visceral resections help compensate for the relatively low wRVU/h. CONCLUSIONS: CRS/HIPEC is an expensive operation, and prolonged LOS has the most significant impact on the total cost of the procedure. High-quality care is essential to improve patient outcomes and maintain the economic sustainability of the procedure.

The Prognostic Significance of Nativity, Enclave Residence, and Socioeconomic Status Among Hispanic Patients with Hepatocellular Carcinoma.

BACKGROUND: Residence in ethnic enclaves and nativity are both associated with survival in Hispanic patients with cancer, although their prognostic significance in patients with hepatocellular carcinoma (HCC) is unknown. We aimed to determine the association between nativity, neighborhood socioeconomic status (nSES), and ethnic enclave residency with overall survival in Hispanic patients with HCC. METHODS: Hispanic patients diagnosed with HCC from 2004 to 2017 were identified in the Texas Cancer Registry. Existing indices were applied to tract-level 2000 US Census data to measure enclave residence and nSES. Enclaves were defined by seven measures. Multivariable Cox proportional hazard models were used to evaluate the association between nativity, enclave residency, and nSES with survival. RESULTS: Among 9496 Hispanic patients with HCC, 2283 (24%) were foreign-born. Compared with US-born Hispanic patients, foreign-born Hispanic patients were less likely to present with localized HCC (45.3% vs. 48.8%, p = 0.03) and less likely to receive HCC treatment (53.9% vs. 47.6%, p < 0.001); however, foreign-born Hispanic patients had lower mortality in adjusted models (adjusted hazard ratio [aHR] 0.86, 95% confidence interval [CI] 0.79-0.93). Neighborhood SES, but not enclave residence, was also associated with overall survival. Compared with those in low nSES non-enclaves, Hispanic patients in high nSES neighborhoods, with either enclave (aHR 0.80, 95% CI 0.72-0.88) or non-enclave (aHR 0.89, 95% CI 0.80-0.98) residence status and low nSES enclaves (aHR 0.93, 95% CI 0.86-0.98) had improved survival. CONCLUSION: In Hispanic patients with HCC, foreign birthplace and higher nSES, but not enclave residence, are associated with improved survival. Additional research on intersectionality between ethnicity, nativity, and neighborhood context is warranted.

Enhancing Readability of Online Patient-Facing Content: The Role of AI Chatbots in Improving Cancer Information Accessibility.

BACKGROUND: Internet-based health education is increasingly vital in patient care. However, the readability of online information often exceeds the average reading level of the US population, limiting accessibility and comprehension. This study investigates the use of chatbot artificial intelligence to improve the readability of cancer-related patient-facing content. METHODS: We used ChatGPT 4.0 to rewrite content about breast, colon, lung, prostate, and pancreas cancer across 34 websites associated with NCCN Member Institutions. Readability was analyzed using Fry Readability Score, Flesch-Kincaid Grade Level, Gunning Fog Index, and Simple Measure of Gobbledygook. The primary outcome was the mean readability score for the original and artificial intelligence (AI)-generated content. As secondary outcomes, we assessed the accuracy, similarity, and quality using F1 scores, cosine similarity scores, and section 2 of the DISCERN instrument, respectively. RESULTS: The mean readability level across the 34 websites was equivalent to a university freshman level (grade 13±1.5). However, after ChatGPT's intervention, the AI-generated outputs had a mean readability score equivalent to a high school freshman education level (grade 9±0.8). The overall F1 score for the rewritten content was 0.87, the precision score was 0.934, and the recall score was 0.814. Compared with their original counterparts, the AI-rewritten content had a cosine similarity score of 0.915 (95% CI, 0.908-0.922). The improved readability was attributed to simpler words and shorter sentences. The mean DISCERN score of the random sample of AI-generated content was equivalent to "good" (28.5±5), with no significant differences compared with their original counterparts. CONCLUSIONS: Our study demonstrates the potential of AI chatbots to improve the readability of patient-facing content while maintaining content quality. The decrease in requisite literacy after AI revision emphasizes the potential of this technology to reduce health care disparities caused by a mismatch between educational resources available to a patient and their health literacy.

Intensifying supportive care is associated with improved survival in gastric cancer patients with malignant ascites.

BACKGROUND: Gastric cancer patients with malignant ascites often have poor functional status and malnutrition that preclude receipt of systemic therapies. Thus, these patients have a very poor prognosis. Beginning in 2019, our multidisciplinary gastric cancer disease-oriented team implemented a more aggressive supportive care plan for gastric cancer patients with malignant ascites. The initiative included measures such as supplemental enteral nutrition, ascites drainage, and initiation of chemotherapy on an inpatient basis. We compared outcomes for gastric cancer patients who presented with synchronous malignant ascites treated before and after the implementation of the care plan. METHODS: We performed a retrospective review of our institutional database to identify patients diagnosed with gastric adenocarcinoma and synchronous malignant ascites between 2010 and 2022. We compared overall survival (OS) between patients diagnosed from 2010 to 2018, which will be referred to as the historical control era and patients diagnosed from 2019 to 2022, which will be called the aggressive supportive care era. RESULTS: Fifty-four patients were included in our analysis; 31 patients were treated in the historical control time frame, and 23 patients were treated during the aggressive supportive care era. Demographic, clinical, and pathologic characteristics were similar between groups. 3% of historical controls received supplemental tube feeds at diagnosis as compared to 30% of the aggressive supportive care cohort (p < 0.01). 3% of historical controls received their first cycle of chemotherapy in the inpatient setting versus 39% of patients treated during the aggressive supportive care era (p < 0.01). The median number of chemotherapy cycles received was 5 among historical controls and 9.5 among aggressive supportive care era patients (p = 0.02). There was no difference in the number of days spent as an inpatient between the two groups. The median OS for historical control patients was 5.4 months as compared with 10.4 months for patients treated during aggressive supportive care era (p = 0.04). CONCLUSIONS: Gastric cancer patients with synchronous malignant ascites treated during a timeframe when our multidisciplinary team implemented more aggressive supportive care measures had improved OS as compared with historic controls. Our results suggest that aggressive supportive measures for these patients with highly challenging clinical issues and poor prognosis can prolong survival. Specifically, initiation of chemotherapy in the inpatient setting and supplemental nutrition should be considered for patients at high risk for treatment intolerance.

Presence of underlying cirrhosis is associated with increased in-hospital mortality and length of stay following pancreatoduodenectomy.

BACKGROUND: Patient- and hospital-level factors associated with outcomes following pancreatoduodenectomy (PD) are well established. However, despite theoretical disruption in hepatopetal flow, the impact of cirrhosis on in-hospital mortality following PD is not well-studied. The objective of this study was to evaluate in-hospital mortality, length of stay (LOS), and post-discharge disposition in patients with cirrhosis undergoing PD. METHODS: A retrospective analysis of the National Inpatient Sample (January 2002-August 2015) was conducted identifying patients undergoing PD. Using previously validated ICD-9-CM codes, patients were stratified into presence and absence of cirrhosis. Factors associated with in-hospital mortality following PD were analyzed adjusting for patient- and hospital-level factors. Following PD were analyzed after adjusting for patient- and hospital-level factors. RESULTS: In 16,344 patients that underwent PD, 203 (1.2 %) patients had underlying cirrhosis prior to resection. Overall in-hospital mortality following PD was significantly worse in the cirrhosis cohort (11.3 % vs. 3.6 %, p < 0.001). Patients with underlying cirrhosis were less likely to be discharged home (73.9 % vs. 83.2 %, p < 0.001) and had a longer median LOS (12.0 vs. 10.0 days, p = 0.001). CONCLUSION: The presence of underlying cirrhosis is associated with increased in-hospital mortality, longer LOS, and decreased likelihood of home discharge following PD. Given the prohibitive risks, PD should not be performed in patients with underlying cirrhosis.

Association of race, demographic and socioeconomic factors with failure to rescue after hepato-pancreato-biliary surgery in the United States.

BACKGROUND: We aimed to describe the association of patient-related factors such as race, socioeconomic status, and insurance on failure to rescue (FTR) after hepato-pancreato-biliary (HPB) surgeries. METHODS: Using the National Inpatient Sample, we analyzed 98,788 elective HPB surgeries between 2004 and 2017. Major and minor complications were identified using ICD9/10 codes. We evaluated mortality rates and FTR (inpatient mortality after major complications). We used multivariate logistic regression analysis to assess racial, socioeconomic, and demographic factors on FTR, adjusting for covariates. RESULTS: Overall, 43 % of patients (n = 42,256) had pancreatic operations, 36% (n = 35,526) had liver surgery, and 21% (n = 21,006) had biliary interventions. The overall major complication rate was 21% (n = 20,640), of which 8% (n = 1655) suffered FTR. Factors independently associated with increased risk for FTR were male sex, older age, higher Charlson Comorbidity Index, Hispanic ethnicity, Asian or other race, lower income quartile, Medicare insurance, and southern region hospitals. CONCLUSIONS: Medicare insurance, male gender, Hispanic ethnicity, and lower income quartile were associated with increased risk for FTR. Efforts should be made to improve the identification and subsequent treatment of complications for those at high risk of FTR.

Serum Interleukin 6 Level is Associated With Overall Survival and Treatment Response in Gastric and Gastroesophageal Junction Cancer.

OBJECTIVE: To identify novel prognostic and predictive biomarkers for gastric and gastroesophageal junction (G+GEJ) adenocarcinoma. BACKGROUND: There are few biomarkers to guide treatment for G+GEJ. The systemic inflammatory response of G+GEJ patients is associated with survival. In this study, we evaluated the relationship of circulating serum cytokine levels with overall survival (OS) and pathologic tumor regression grade (TRG) in G+GEJ patients. PATIENTS AND METHODS: We queried the UT Southwestern gastric cancer biobank to identify consecutive patients diagnosed with G+GEJ from 2016 to 2022; these patients had pretreatment serum collected at diagnosis. For patients who received neoadjuvant therapy, an additional serum sample was collected immediately before surgical resection. An unbiased screen of 17 cytokines was measured in a discovery cohort. A multivariable Cox proportional hazards model was used to assess the association of cytokine concentration with OS. Findings were validated in additional patients. In patients who received neoadjuvant therapy, we assessed whether the change in interleukin 6 (IL-6) after therapy was associated with TRG. RESULTS: Sixty-seven patients were included in the discovery cohort, and IL-6 was the only pretreatment cytokine associated with OS; this was validated in 134 other patients (hazard ratio: 1.012 per 1 pg/mL increase, 95% CI: 1.006-1.019, P = 0.0002). Patients in the top tercile of IL-6 level had worse median OS (10.6 months) compared with patients in the intermediate (17.4 months) and bottom tercile (35.8 months, P < 0.0001). Among patients who underwent neoadjuvant therapy (n = 50), an unchanged or decrease in IL-6 level from pretreatment to posttreatment, had a sensitivity and specificity of 80% for predicting complete or near-complete pathologic tumor regression (TRG 0-1). CONCLUSIONS: Pretreatment serum level of IL-6 is a promising prognostic biomarker for G+GEJ patients. Comparing pre and post-neoadjuvant IL-6 levels may predict pathologic response to neoadjuvant therapy.

Hospital Designations and Their Impact on Guideline-Concordant Care and Survival in Pancreatic Cancer. Do They Matter?

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) requires complex multidisciplinary care. European evidence suggests potential benefit from regionalization, however, data characterizing the ideal setting in the United States are sparse. Our study compares the significance of four hospital designations on guideline-concordant care (GCC) and overall survival (OS). PATIENTS AND METHODS: The Texas Cancer Registry was queried for 17,071 patients with PDAC treated between 2004 and 2015. Clinical data were correlated with hospital designations: NCI designated (NCI), high volume (HV), safety net (SNH), and American College of Surgeons Commission on Cancer accredited (ACS). Univariable (UVA) and multivariable (MVA) logistic regression were used to assess associations with GCC [on the basis of National Comprehensive Cancer Network (NCCN) recommendations]. Cox regression analysis assessed survival. RESULTS: Only 43% of patients received GCC. NCI had the largest associated risk reduction (HR 0.61, CI 0.58-0.65), followed by HV (HR 0.87, CI 0.83-0.90) and ACS (HR 0.91, CI 0.87-0.95). GCC was associated with a survival benefit in the full (HR 0.75, CI 0.69-0.81) and resected cohort (HR 0.74, CI 0.68-0.80). NCI (OR 1.52, CI 1.37-1.70), HV (OR 1.14, CI 1.05-1.23), and SNH (OR 0.78, CI 0.68-0.91) all correlated with receipt of GCC. For resected patients, ACS (OR 0.63, CI 0.50-0.79) and SNH (OR 0.50, CI 0.33-0.75) correlate with GCC. CONCLUSIONS: A total of 43% of patients received GCC. Treatment at NCI and HV correlated with improved GCC and survival. Including GCC as a metric in accreditation standards could impact survival for patients with PDAC.

Defining the Price Tag of Complications Following Pancreatic Surgery: A US National Perspective.

INTRODUCTION: Pancreatic surgery tends to have a high rate of postoperative complications due to its complex nature, significantly increasing hospital costs. Our aim was to describe the true association between complications and hospital costs in a national cohort of US patients. METHODS: The National Inpatient Sample was used to conduct a retrospective analysis of elective pancreatic resections performed between 2004 and 2017, categorizing them based on whether patients experienced major complications (MaC), minor complications (MiC), or no complications (NC). Multivariable quantile regression was used to analyze how costs varied at different percentiles of the cost curve. RESULTS: Of 37,893 patients, 45.3%, 28.6%, and 26.1% experienced NC, MiC, and MaC, respectively. Factors associated with MaC were a Charlson Comorbidity Index of ≥4, prolonged length of stay, proximal pancreatectomy, older age, male sex, and surgery performed at hospitals with a small number of beds or at urban nonteaching hospitals (all P < 0.01). Multivariable quantile regression revealed significant variation in MiC and MaC across the cost curve. At the 50th percentile, MiC increased the cost by $3352 compared to NC while MaC almost doubled the cost of the surgery, increasing it by $20,215 (both P < 0.01). The association between complications and cost was even greater at the 95th percentile, increasing the cost by $10,162 and $108,793 for MiC and MaC, respectively (P < 0.01). CONCLUSIONS: MiC and MaC were significantly associated with increased hospital costs. Furthermore, the relationship between MaC and costs was especially apparent at higher percentiles of the cost curve.

Factors associated with failure to operate and its impact on survival in early-stage pancreatic cancer.

INTRODUCTION: Curative intent for localized pancreatic cancer (pancreatic ductal adenocarcinoma [PDAC]) requires surgery, but despite improved perioperative outcomes, surgery remains underutilized. This study analyzed the Texas Cancer Registry (TCR) to identify resectable PDAC patients who underwent curative-intent surgery in Texas between 2004 and 2018. We then evaluated demographic and clinical factors associated with failure to operate and survival (OS). METHODS: We identified patients with localized PDAC or regional lymph node spread between 2004 and 2018 in the TCR. Resection rates were determined and multivariable regression and cox proportional hazards were used to identify factors associated with failure to OS. RESULTS: Of 4274 patients, 22% underwent resection, 57% were not offered surgery, 6% had comorbidities precluding surgery, and 3% refused. Resection rates decreased from 31% in 2004 to 22% in 2018. Increasing age was associated with failure to operate (odds ratio [OR] 2.55; 95% confidence interval [CI] 1.80-3.61; p < 0.0001) while treatment at a Commission on Cancer (CoC) center correlated with reduced failure to operate (OR 0.63; 95% CI 0.50-0.78; p < 0.0001). Resection correlated with survival (HR 0.34; 95% CI 0.31-0.38; p < 0.0001) as did treatment at a National Cancer Institute (NCI)-designated center (hazard ratio 0.79; 95% CI 0.70-0.89; p < 0.0001). CONCLUSIONS: Surgery is underutilized for the treatment of resectable PDAC in Texas with decreasing utilization, annually. Evaluation at CoC was associated with improved resection rates and NCI was associated with increased survival. Expanding access to multidisciplinary care including trained hepato-pancreatico-biliary surgeons may improve outcomes for PDAC patients.

Lenvatinib inhibits the growth of gastric cancer patient-derived xenografts generated from a heterogeneous population.

BACKGROUND: Lenvatinib is a multitargeted tyrosine kinase inhibitor that is being tested in combination with immune checkpoint inhibitors to treat advanced gastric cancer; however, little data exists regarding the efficacy of lenvatinib monotherapy. Patient-derived xenografts (PDX) are established by engrafting human tumors into immunodeficient mice. The generation of PDXs may be hampered by growth of lymphomas. In this study, we compared the use of mice with different degrees of immunodeficiency to establish PDXs from a diverse cohort of Western gastric cancer patients. We then tested the efficacy of lenvatinib in this system. METHODS: PDXs were established by implanting gastric cancer tissue into NOD.Cg-PrkdcscidIl2rgtm1Wjl/SzJ (NSG) or Foxn1nu (nude) mice. Tumors from multiple passages from each PDX line were compared histologically and transcriptomically. PDX-bearing mice were randomized to receive the drug delivery vehicle or lenvatinib. After 21 days, the percent tumor volume change (%Δvtumor) was calculated. RESULTS: 23 PDX models were established from Black, non-Hispanic White, Hispanic, and Asian gastric cancer patients. The engraftment rate was 17% (23/139). Tumors implanted into NSG (16%; 18/115) and nude (21%; 5/24) mice had a similar engraftment rate. The rate of lymphoma formation in nude mice (0%; 0/24) was lower than in NSG mice (20%; 23/115; p < 0.05). PDXs derived using both strains maintained histologic and gene expression profiles across passages. Lenvatinib treatment (mean %Δvtumor: -33%) significantly reduced tumor growth as compared to vehicle treatment (mean %Δvtumor: 190%; p < 0.0001). CONCLUSIONS: Nude mice are a superior platform than NSG mice for generating PDXs from gastric cancer patients. Lenvatinib showed promising antitumor activity in PDXs established from a diverse Western patient population and warrants further investigation in gastric cancer.

Variation of Hepatocellular Carcinoma Treatment Patterns and Survival Across Geographic Regions in a Veteran Population.

BACKGROUND: Veteran populations have five times the incidence of hepatocellular carcinoma (HCC) compared with the general population. The incidence of HCC has increased in the Veteran's Affairs Health System (VAHS), primarily due to the increased prevalence of cirrhosis. This study aimed to characterize differences in treatment patterns and overall survival rates across the five VAHS geographic regions. METHODS: Using the VA Corporate Data Warehouse, the authors built a comprehensive national dataset of Veteran patients with HCC diagnosed between 2001 and 2015 to compare patients across VAHS regions. A multivariable Cox proportional hazards model was used to identify factors associated with 5-year all-cause mortality. Kaplan-Meier curves were used to visualize the patient survival function, and the log-rank test was applied to test statistical significance. RESULTS: This retrospective study analyzed 13,434 patients. The West region had the highest rate of overall treatment receipt (63.6%), and the Southwest had the lowest rate (52.9%). After adjustment for demographic, clinicopathologic, treatment, and hospital factors, treatment in a non-West region continued to be significantly associated with a 10% to 13% increased risk of 5-year mortality (Midwest: hazard ratio [HR], 1.11; 95% confidence interval [CI], 1.03-1.17; Northeast: HR, 1.10; 95% CI, 1.03-1.17; Southeast: HR, 1.13; 95% CI, 1.06-1.21; Southwest: HR, 1.11; 95% CI, 1.03-1.19) (p < 0.01). CONCLUSIONS: Treatment patterns and overall survival rates of HCC patients differ significantly across VAHS geographic regions. Targeted interventions to increase the rate of treatment in the non-West regions are needed to improve survival of HCC Veterans and provide uniformly high-quality care across VAHS facilities.

Nativity Status is an Important Social Determinant of Health for Hispanic Patients with Gastric Cancer in Texas.

BACKGROUND: The U.S. foreign-born population is rapidly increasing, and cancer incidence/mortality rates have been shown to differ by nativity status. Our study aimed to characterize differences in gastric cancer presentation and survival among Hispanic patients in Texas by nativity status. METHODS: We conducted a retrospective review of the Texas Cancer Registry to identify Hispanic patients diagnosed with gastric adenocarcinoma between 2004 and 2017. Existing indices applied to 2010 census tract-level data were utilized to measure neighborhood socioeconomic status (nSES) and Hispanic enclaves. Nativity status was imputed for patients with missing data. Multivariable Cox proportional hazard models were fit for overall survival adjusted for age, insurance status, diagnosis year, tumor location, stage, grade, reporting source, nativity status, nSES, and Hispanic enclave. RESULTS: Our study cohort consisted of 6186 patients and 39% were foreign-born. A greater proportion of foreign-born patients were diagnosed at < 45 years old (16% vs. 11%, p < 0.0001) and had metastatic disease at presentation (47% vs. 34%, p < 0.0001). Foreign-born patients were more often uninsured, in the lowest nSES quintile, and the highest (most ethnically distinct) quintile for Hispanic enclave. Stage-specific overall survival was significantly higher among foreign-born patients. In our multivariate model, foreign-born Hispanic patients had improved survival versus US-born (hazard ratio [HR] 0.90, 95% confidence interval [CI] 0.82-0.99). CONCLUSIONS: The clinical presentation of gastric cancer differs significantly between foreign-born and U.S.-born Hispanic patients. Foreign-born Hispanic patients have improved survival after adjusting for socioeconomic, neighborhood, and clinical factors. Further studies are needed to identify specific causal mechanisms driving the observed survival difference by nativity status.

Machine Learning Improves Prediction Over Logistic Regression on Resected Colon Cancer Patients.

INTRODUCTION: Despite advances, readmission and mortality rates for surgical patients with colon cancer remain high. Prediction models using regression techniques allows for risk stratification to aid periprocedural care. Technological advances have enabled large data to be analyzed using machine learning (ML) algorithms. A national database of colon cancer patients was selected to determine whether ML methods better predict outcomes following surgery compared to conventional methods. METHODS: Surgical colon cancer patients were identified using the 2013 National Cancer Database (NCDB). The negative outcome was defined as a composite of 30-d unplanned readmission and 30- and 90-d mortality. ML models, including Random Forest and XGBoost, were built and compared with conventional logistic regression. For the accounting of unbalanced outcomes, a synthetic minority oversampling technique (SMOTE) was implemented and applied using XGBoost. RESULTS: Analysis included 528,060 patients. The negative outcome occurred in 11.6% of patients. Model building utilized 30 variables. The primary metric for model comparison was area under the curve (AUC). In comparison to logistic regression (AUC 0.730, 95% CI: 0.725-0.735), AUC's for ML algorithms ranged between 0.748 and 0.757, with the Random Forest model (AUC 0.757, 95% CI: 0.752-0.762) outperforming XGBoost (AUC 0.756, 95% CI: 0.751-0.761) and XGBoost using SMOTE data (AUC 0.748, 95% CI: 0.743-0.753). CONCLUSIONS: We show that a large registry of surgical colon cancer patients can be utilized to build ML models to improve outcome prediction with differential discriminative ability. These results reveal the potential of these methods to enhance risk prediction, leading to improved strategies to mitigate those risks.

Uncovering Biological Factors That Regulate Hepatocellular Carcinoma Growth Using Patient-Derived Xenograft Assays.

BACKGROUND AND AIMS: Several major factors limit our understanding of hepatocellular carcinoma (HCC). First, human HCCs are infrequently biopsied for diagnosis and thus are not often biologically interrogated. Second, HCC initiation and progression are strongly influenced by the cirrhotic microenvironment, and the exact contributions of intrinsic and extrinsic tumor factors are unclear. A powerful approach to examine the personalized biology of liver cancers and the influence of host tissues is with patient-derived xenograft (PDX) models. In Asia, HCCs from patients with hepatitis B virus have been efficiently converted into PDXs, but few parallel efforts from the west have been reported. APPROACH AND RESULTS: In a large-scale analysis, we implanted 93 HCCs and 8 cholangiocarcinomas (CCAs) to systematically analyze host factors and to define an optimized platform for PDX development from both surgical and biopsy samples. NOD Scid IL-2Rγ-/- (NSG) mice that had undergone partial hepatectomy (PHx) represented the best combination of engraftability, growth, and passageability, but overall rates were low and indicative of a unique intrinsic biology for HCCs in the United States. PDX models preserved the histology and genetic features of parental tumors, and ultimately, eight models were usable for preclinical studies. Intriguingly, HCC PDXs were differentially sensitive to regorafenib and sorafenib, and CCA PDXs were also highly sensitive to regorafenib. CONCLUSIONS: PDX models functionalize early and advanced stage HCCs and revealed unique biological features of liver cancers from the United States.

Redefining High-Volume Gastric Cancer Centers: The Impact of Operative Volume on Surgical Outcomes.

BACKGROUND: Performance of technically complex surgery at high-volume (HV) centers is associated with improved outcomes. OBJECTIVE: The aim of this study was to assess whether hospital gastrectomy volume is associated with surgical outcomes, and what threshold of case volume meaningfully impacts surgical outcomes. METHODS: We conducted a retrospective review of adult NCDB patients with gastric adenocarcinoma undergoing gastrectomy between 2004 and 2015. A multivariable Cox proportional hazards model with restricted cubic splines was used to examine the association of annual hospital gastrectomy volume and overall survival. Bootstrap simulation was used to estimate the cut-point corresponding to maximum change in log hazard ratio. Hospitals were divided into HV (≥ 17 cases/year) and low-volume (LV; < 17 cases/year) groups. We examined the relationship between volume groups and adequate nodal examination, R0 resection, unplanned readmission, and 30- and 90-day mortality. RESULTS: Our cohort consisted of 29,559 patients (7.8% treated at an HV center). Treatment at an HV center was associated with an increased likelihood of adequate nodal examination [odds ratio (OR) 2.12, 95% confidence interval (CI) 1.94-2.32] and R0 resection among patients with cardia tumors (OR 1.42, 95% CI 1.07-1.88). Patients treated at HV centers had decreased 30- and 90-day postoperative mortality, which was more pronounced in those undergoing total gastrectomy. CONCLUSIONS: Treatment at an HV gastrectomy center is associated with improved surgical outcomes. Our study identified 17 cases/year as a clinically meaningful distinction between HV and LV centers. This definition of an HV center should be considered when evaluating regionalization of gastric cancer care to improve patient outcomes.

Inaccurate Clinical Stage Is Common for Gastric Adenocarcinoma and Is Associated with Undertreatment and Worse Outcomes.

BACKGROUND: Accurate clinical staging (CS) of gastric cancer is critical for appropriate treatment selection and prognostication, but CS remains highly imprecise. Our study evaluates factors associated with inaccurate CS, the impact of inaccurate CS on outcomes, and utilization of adjuvant therapy in patients who are understaged. METHODS: We conducted a retrospective review of NCDB patients diagnosed with clinical early stage gastric adenocarcinoma (cT1-2N0M0) between 2004 and 2016. Patients not undergoing upfront gastrectomy or with missing pathologic staging were excluded. Patients were classified as accurately staged, inaccurately staged with receipt of adjuvant therapy (IS+), and inaccurately staged with no receipt of adjuvant therapy (IS-). Logistic regression was utilized to assess the impact of factors on CS accuracy and receipt of adjuvant therapies. Kaplan-Meier and Cox proportional hazard methods were used for survival analysis. RESULTS: Approximately 40% of patients were inaccurately staged (IS). cT2, moderately/poorly differentiated, and site-overlapping tumors were associated with increased likelihood of being IS. Treatment at an academic facility was associated with decreased likelihood of understaging. Only 54% of patients who were IS received adjuvant therapy. CONCLUSION: Accurate CS of gastric cancer remains inadequate. Understaging is associated with detrimental effects on receiving guideline-concordant care and, possibly, patient outcomes. Targeted interventions reducing the proportion of understaged patients and ensuring receipt of appropriate therapy is needed to optimize outcomes. Patients with high-risk disease that are frequently understaged may benefit from selective neoadjuvant therapy. Centralization of gastric cancer care may also be a key strategy in improving receipt of guideline-concordant therapies.

Treatment and Survival Disparities of Colon Cancer in the Texas-Mexico Border Population: Cancer Disparities in Border Population.

BACKGROUND: Previous studies have reported healthcare disparities in the Texas-Mexico border population. Our aim was to evaluate treatment utilization and oncologic outcomes of colon cancer patients in this vulnerable population. METHODS: Patients with localized and regional colon cancer (CC) were identified in the Texas Cancer Registry (1995-2016). Clinicopathological data, hospital factors, receipt of optimal treatment, and overall survival (OS) were compared between Texas-Mexico Border (TMB) and the Non-Texas-Mexico Border (NTMB) cohorts. Multivariable analysis was performed to identify risk factors associated with decreased survival. RESULTS: We identified 43,557 patients with localized/regional CC (9% TMB and 91% NTMB). TMB patients were more likely to be Hispanic (73% versus 13%), less likely to have private insurance (13% versus 21%), were more often treated at safety net hospitals (82% versus 22%) and less likely at ACS-CoC accredited hospitals (32% versus 57%). TMB patients were more likely to receive suboptimal treatment (21% versus 16%) and had a lower median OS for localized (8.58 versus 9.58 y) and regional colon cancer (5.75 versus 6.18 y, all P < 0.001). In multivariable analysis, TMB status was not associated with worse OS. Factors associated with worse survival included receipt of suboptimal treatment, Medicare/insured status, and treatment in safety net and non-accredited ACS-CoC hospitals (all P < 0.001) CONCLUSIONS: While TMB CC patients had worse OS, TMB status itself was not found to be a risk factor for decreased survival. This survival disparity is likely associated with higher rate of suboptimal treatment, Medicare/Uninsured status, and decreased access to ACS-CoC accredited hospitals.