Racial Disparities in Recurrence and Overall Survival in Patients With Locoregional Colorectal Cancer

Race norming and biases in surgical oncology care

Disparities in surgical oncology care may be due to race/ethnicity. Race norming, defined as the adjustment of medical assessments based on an individual's race/ethnicity, and implicit bias are specifically explored in this focused systematic review. We aim to examine how race norming and bias impact oncologic care and postsurgical outcomes, particularly in Black patient populations, while providing potential strategies to improve equitable and inclusive care.

Colon Cancer Survival Among South Asian Americans: A Cross-Sectional Analysis of a National Dataset

INTRODUCTION

Colon cancer (CC) is one of the most common cancers among South Asian Americans (SAAs). The objective of this study was to measure differences in risk-adjusted survival among SAAs with CC compared to non-Hispanic Whites (NHWs) using a representative national dataset from the United States.

METHODS

A retrospective analysis of patients with CC in the National Cancer Database (2004-2020) was performed. Differences in presentation, management, median overall survival (OS), three-year survival, and five-year survival between SAAs and NHWs were compared. Kaplan-Meier analysis and multivariable Cox regression were used to assess differences in survival outcomes, adjusting for demographics, presentation, and treatments received.

RESULTS

Data from 2873 SAA and 639,488 NHW patients with CC were analyzed. SAAs were younger at diagnosis (62.2 versus 69.5 y, P < 0.001), higher stage (stage III [29.0% versus 26.2%, P = 0.001] or Stage IV [21.4% versus 20.0%, P = 0.001]), and experienced delays to first treatment (SAA 5.9% versus 4.9%, P = 0.003). SAAs with CC had higher OS (median not achieved versus 68.1 mo for NHWs), three-year survival (76.3% versus 63.4%), and five-year survival (69.1% versus 52.9%). On multivariable Cox regression, SAAs with CC had a lower risk of death across all stages (hazard ratio: 0.64, P < 0.001).

CONCLUSIONS

In this national study, SAA patients with CC presented earlier in life with more advanced disease, and a higher proportion experienced treatment delay compared to NHW patients. Despite these differences, SAAs had better adjusted OS than NHW, warranting further exploration of tumor biology and socioeconomic determinants of cancer outcomes in SAAs.

Disparities in Outcomes following Resection of Locally Advanced Rectal Cancer

Surgical margins following rectal cancer resection impact oncologic outcomes. We examined the relationship between margin status and race, ethnicity, region of care, and facility type. Patients undergoing resection of a stage II-III locally advanced rectal cancer (LARC) between 2004 and 2018 were identified through the National Cancer Database. Inverse probability of treatment weighting (IPTW) was performed, with margin positivity rate as the outcome of interest, and race/ethnicity and region of care as the predictors of interest. In total, 58,389 patients were included. After IPTW adjustment, non-Hispanic Black (NHB) patients were 12% (p = 0.029) more likely to have margin positivity than non-Hispanic White (NHW) patients. Patients in the northeast were 9% less likely to have margin positivity compared to those in the south. In the west, NHB patients were more likely to have positive margins than NHW patients. Care in academic/research centers was associated with lower likelihood of positive margins compared to community centers. Within academic/research centers, NHB patients were more likely to have positive margins than non-Hispanic Other patients. Our results suggest that disparity in surgical management of LARC in NHB patients exists across regions of the country and facility types. Further research aimed at identifying drivers of this disparity is warranted.

Phase II Trial of Cisplatin, Gemcitabine, and Intensity-Modulated Radiation Therapy for Locally Advanced Vulvar Squamous Cell Carcinoma: NRG Oncology/GOG Study 279

PURPOSE

To assess efficacy and toxicity of cisplatin (C) and gemcitabine (G) with intensity-modulated radiation therapy (IMRT) in patients with locally advanced vulvar cancer not amenable to surgery.

METHODS

Patients enrolled in a single-arm phase II study. Pretreatment inguinal-femoral nodal assessment was performed. Sixty-four Gy IMRT was prescribed to the vulva, with 50-64 Gy delivered to the groins/low pelvis. Radiation therapy (RT) plans were quality-reviewed pretreatment. C 40 mg/m2 and G 50 mg/m2 were administered once per week throughout IMRT. Complete pathologic response (CPR) was the primary end point. Progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan-Meier method, and adverse events were assessed with Common Terminology Criteria for Adverse Events v 4.0.

RESULTS

Fifty-seven patients enrolled, of which 52 were evaluable. The median age was 58 years (range, 25-58), and 94% were White. Forty (77%) had stage II or III disease, and all had squamous histology. A median of six chemotherapy cycles (range, 1-8) were received. Eighty-five percent of RT plans were quality-reviewed with 100% compliance to protocol. Seven patients came off trial because of toxicity or patient withdrawal. Of 52 patients available for pathologic assessment, 38 (73% [90% CI, 61 to 83]) achieved CPR. No pelvic exenterations were performed. With a median follow-up of 51 months, the 12-month PFS was 74% (90% CI, 62.2 to 82.7) and the 24-month OS was 70% (90% CI, 57 to 79). The most common grade 3 or 4 adverse events were hematologic toxicity and radiation dermatitis. There was one grade 5 event unlikely related to treatment.

CONCLUSION

Weekly C and G concurrent with IMRT sufficiently improved CPR in women with locally advanced vulvar squamous cell carcinoma not amenable to surgical resection.

Sleep health and quality of life in the Detroit Research on Cancer Survivors cohort

PURPOSE

Sleep disturbances represent a modifiable target to improve quality of life and longer-term outcomes in cancer survivors. However, the association between sleep health and overall quality of life in African American cancer survivors has been poorly assessed, a population at increased risk for morbidity and mortality.

METHODS

Seven hundred and eighteen Detroit Research on Cancer Survivors (ROCS) cohort participants completed a supplemental sleep survey at the time of enrollment, which included the Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), and Insomnia Severity Index (ISI). Linear and logistic regression was used to evaluate the association between sleep and mental health, while block regression models were used to estimate the contribution of clustered factors to Health-Related Quality of Life (HRQOL).

RESULTS

Nearly 60% of the cohort reported symptoms indicative of poor sleep quality on the PSQI, 15% reported excessive daytime sleepiness on the ESS, and 12% reported moderate to severe insomnia on the ISI. Survivors with elevated ISI scores reported FACT-G scores that were 17 points lower than those without symptoms of insomnia (95% CI: - 13.1, - 21.2). Poor sleep health accounted for the largest proportion of variability in FACT-G scores (R2 = 0.27) and change in R2 value (0.18) when compared to comorbidities, health behaviors, cancer-related factors, and demographics.

CONCLUSIONS

Overall sleep health was significantly associated with poorer HRQOL and variability in FACT-G scores. Additional studies investigating a causal relationship between sleep and HRQOL are needed to determine whether sleep quality could affect disparities in cancer outcomes.

IMPLICATIONS FOR CANCER SURVIVORS

Addressing sleep quality in cancer survivors may improve long-term health and HRQOL.

Association Between Racial and Socioeconomic Disparities and Hospital Performance in Treatment and Outcomes for Patients with Colon Cancer

BACKGROUND

Disparities in colon cancer care and outcomes by race/ethnicity, socioeconomic status (SES), and insurance are well recognized; however, the extent to which inequalities are driven by patient factors versus variation in hospital performance remains unclear. We sought to compare disparities in care delivery and outcomes at low- and high-performing hospitals.

METHODS

We identified patients with stage I-III colon adenocarcinoma from the 2012-2017 National Cancer Database. Adequate lymphadenectomy and timely adjuvant chemotherapy administration defined hospital performance. Multilevel regression models evaluated disparities by race/ethnicity, SES, and insurance at the lowest- and highest-performance quartile hospitals.

RESULTS

Of 92,573 patients from 704 hospitals, 45,982 (49.7%) were treated at 404 low-performing hospitals and 46,591 (50.3%) were treated at 300 high-performing hospitals. Low-performing hospitals treated more non-Hispanic (NH) Black, Hispanic, low SES, and Medicaid patients (all p < 0.01). Among low-performing hospitals, patients with low versus high SES (odds ratio [OR] 0.87, 95% confidence interval [CI] 0.82-0.92), and Medicare (OR 0.90, 95% CI 0.85-0.96) and Medicaid (OR 0.88, 95% CI 0.80-0.96) versus private insurance, had decreased odds of receiving high-quality care. At high-performing hospitals, NH Black versus NH White patients (OR 0.83, 95% CI 0.72-0.95) had decreased odds of receiving high-quality care. Low SES, Medicare, Medicaid, and uninsured patients had worse overall survival at low- and high-performing hospitals (all p < 0.01).

CONCLUSION

Disparities in receipt of high-quality colon cancer care occurred by SES and insurance at low-performing hospitals, and by race at high-performing hospitals. However, survival disparities by SES and insurance exist irrespective of hospital performance. Future steps include improving low-performing hospitals and identifying mechanisms affecting survival disparities.

Race and Ethnicity Disparities in Cardiovascular and Cancer Mortality: the Role of Socioeconomic Status-a Systematic Review and Meta-analysis

To clarify the role of socioeconomic status (SES) in cardiovascular and cancer mortality disparities observed between Black, Hispanic, and Asian compared to White adults, we conducted a meta-analysis of the longitudinal research in the USA. A PubMed, Ovid Medline, Web of Science, and EBSCO search was performed from January 1995 to May 2023. Two authors independently screened the studies and conducted risk assessments, with conflicts resolved via consensus. Studies were required to analyze mortality data using Cox proportional hazard regression. Random-effects models were used to pool hazard ratios (HR) and reporting followed PRISMA guidelines. Twenty-two studies with cardiovascular mortality (White and Black (n = 22), Hispanic (n = 7), and Asian (n = 3) adults) and twenty-three with cancer mortality endpoints (White and Black (n = 23), Hispanic (n = 11), and Asian (n = 10) adults) were included. The meta-analytic sample for cardiovascular mortality endpoints was 6,199,049 adults (White = 4,891,735; Black = 935,002; Hispanic = 295,623; Asian = 76,689), while for cancer-specific mortality endpoints was 7,745,180 adults (White = 5,988,392; Black= 1,070,447; Hispanic= 484,848; Asian = 201,493). Median follow-up was 10 and 11 years in cohorts with cardiovascular and cancer mortality endpoints, respectively. Adjustments for SES attenuated the higher risk for cardiovascular (HR, 1.46; 95% CI, 1.30-1.64) and cancer mortality (HR, 1.35; 95% CI, 1.32-1.38) of Black compared to White adults by 25% (HR, 1.21; 95% CI, 1.15-1.28) and 19% (HR, 1.16; 95% CI, 1.13-1.18), respectively. However, the Hispanic cardiovascular (HR, 0.79; 95% CI, 0.73-0.85) and Asian cancer mortality (HR, 0.81; 95% CI, 0.76-0.86) advantage were independent of SES. These findings emphasize the need to develop strategies focused on SES to reduce cardiovascular and cancer mortality in Black adults.

Reporting of Circumferential Resection Margin in Rectal Cancer Surgery

Importance

Circumferential resection margin (CRM) in rectal cancer surgery is a major prognostic indicator associated with local recurrence and overall survival. Facility rates of CRM positivity have recently been established as a new quality measure by the Commission on Cancer (CoC); however, the completeness of CRM status reporting is not well characterized.

Objective

To describe the changes in CRM reporting and factors associated with low rates of reporting.

Design, Setting, and Participants

A retrospective cohort study was conducted using data from the National Cancer Database between January 2010 and December 2019. Data were analyzed between October 1, 2021, and February 1, 2022. Data from the National Cancer Database included patients diagnosed with nonmetastatic rectal adenocarcinoma receiving surgical treatment at CoC-accredited facilities throughout the US.

Exposures

Patient, tumor, and facility-level factors. Facilities were divided by surgical volume, safety-net status, and CoC facility type.

Main Outcomes and Measures

Circumferential resection margin missingness rates.

Results

A total of 110 571 patients (59.3% men) with rectal adenocarcinoma who underwent curative-intent surgery at 1307 CoC-accredited hospitals were included for analysis. Reporting of CRM improved over the study period, with a mean (SE) missing 12.0% (0.32%) decreased from 16.3% (0.36%). Academic facilities had a higher missingness than other facility types (14.3% vs 10.5%-12.7%; P < .001). Mean (SE) rates of missingness were similar between hospitals of varying volume (lowest quartile: 12.2% [0.93%] vs highest quartile: 12.4% [0.53%]; P = .96). Cases in which fewer than 12 lymph nodes were removed had higher rates of missingness (18.1% vs 11.4%; P < .001). Increased odds of CRM missingness were noted with T category (odds ratio [OR], 1.50; 95% CI, 1.35-1.65) and N category (OR, 2.00; 95% CI, 1.82-2.20). Black race was associated with missingness (OR, 1.13; 95% CI, 1.06-1.14).

Conclusion and Relevance

Although CRM positivity reporting has improved over the last decade, the findings of this study suggest there is substantial room for improvement as it becomes a quality standard. Missingness appears to be associated with poor performance on other quality metrics and facility type. This measure appears to be ideal for targeted institution-level feedback to improve quality of care nationally.

Time Period of Treatment's Effect on the Association Between Race and Survival in Patients With Malignant Colorectal Adenocarcinoma

BACKGROUND

Colorectal cancer is one of the most common malignancies diagnosed in the United States, with 126,240 new cases diagnosed in 2020. Past studies have shown that disparities may exist between certain patient populations, but it is unknown how they are affected over time as treatments evolve. The purpose of this study was to determine whether the decade of treatment modifies the association between race and five-year survival in adults diagnosed and treated for malignant colorectal adenocarcinomas since the 1970s.

METHODS

This was a non-concurrent retrospective cohort study using data from the Surveillance, Epidemiology, and End Results (SEER) database of the National Cancer Institute. The inclusion criteria involved patients with primary malignant colorectal adenocarcinoma between the years 1975 and 2018. Exclusion criteria included previous malignancies or missing information on any of the variables. The exposure variable was the patient's race, and the main outcome variable was average five-year survival rates. The effect modifier was the time period in which the patient received treatment. The covariates of the study included age, sex, Hispanic status, surgical intervention recommendation, and disease stage. Unadjusted and adjusted hazard ratios (HRs) and corresponding 95% confidence intervals (CIs) were calculated using Cox regression models.

RESULTS

As the interaction term between race/ethnicity and year of diagnosis was statistically significant, the data were stratified according to year of diagnosis. Black patients in both time periods had a higher mortality rate from malignant colorectal carcinoma after adjustment for the covariates (1975-1990: HR 1.10, 95% CI 1.06-1.15; 1991-2018: HR 1.19, 95% CI 1.16-1.23) when compared with White patients. American Indian, Alaskan Native, and Asian patients were found to have lower mortality in both time periods when compared with White patients (1975-1990: HR 0.90, 95% CI 0.85-0.95; 1991-2018: HR 0.93, 95% CI 0.89-0.96).

CONCLUSION

Our data found that despite the evolution in the standard of care treatment for malignant colorectal adenocarcinoma since the year 1975, Black patients had lower five-year survival rates when compared with their White counterparts as well as increased rates of being diagnosed with this disease. Overall, addressing these disparities in colorectal cancer outcomes is critical for improving public health and reducing healthcare costs.

Colon Cancer Disparities in Stage at Presentation and Time to Surgery for Asian Americans, Native Hawaiians, and Pacific Islanders: A Study with Disaggregated Ethnic Groups

BACKGROUND

Vast differences in barriers to care exist among Asian American, Native Hawaiian, and Pacific Islander (AANHPI) groups and may manifest as disparities in stage at presentation and access to treatment. Thus, we characterized AANHPI patients with stage 0-IV colon cancer and examined differences in (1) stage at presentation and (2) time to surgery relative to white patients.

PATIENTS AND METHODS

We assessed all patients in the National Cancer Database (NCDB) with stage 0-IV colon cancer from 2004 to 2016 who identified as white, Chinese, Japanese, Filipino, Native Hawaiian, Korean, Vietnamese, Laotian, Hmong, Kampuchean, Thai, Asian Indian or Pakistani, and Pacific Islander. Multivariable ordinal logistic regression defined adjusted odds ratios (AORs), with 95% confidence intervals (CI), of (1) patients presenting with advanced stage colon cancer and (2) patients with stage 0-III colon cancer receiving surgery at ≥ 60 days versus 30-59 days versus < 30 days postdiagnosis, adjusting for sociodemographic/clinical factors.

RESULTS

Among 694,876 patients, Japanese [AOR 1.08 (95% CI 1.01-1.15), p < 0.05], Filipino [AOR 1.17 (95% CI 1.09-1.25), p < 0.001], Korean [AOR 1.09 (95% CI 1.01-1.18), p < 0.05], Laotian [AOR 1.51 (95% CI 1.17-1.95), p < 0.01], Kampuchean [AOR 1.33 (95% CI 1.04-1.70), p < 0.01], Thai [AOR 1.60 (95% CI 1.22-2.10), p = 0.001], and Pacific Islander [AOR 1.41 (95% CI 1.20-1.67), p < 0.001] patients were more likely to present with more advanced colon cancer compared with white patients. Chinese [AOR 1.27 (95% CI 1.17-1.38), p < 0.001], Japanese [AOR 1.23 (95% CI 1.10-1.37], p < 0.001], Filipino [AOR 1.36 (95% CI 1.22-1.52), p < 0.001], Korean [AOR 1.16 (95% CI 1.02-1.32), p < 0.05], and Vietnamese [AOR 1.55 (95% CI 1.36-1.77), p < 0.001] patients were more likely to experience greater time to surgery than white patients. Disparities persisted when comparing among AANHPI subgroups.

CONCLUSIONS

Our findings reveal key disparities in stage at presentation and time to surgery by race/ethnicity among AANHPI subgroups. Heterogeneity upon disaggregation underscores the importance of examining and addressing access barriers and clinical disparities.

A Multi-Omics Overview of Colorectal Cancer to Address Mechanisms of Disease, Metastasis, Patient Disparities and Outcomes

Human colorectal cancer (CRC) is one of the most common malignancies in men and women across the globe, albeit CRC incidence and mortality shows a substantial racial and ethnic disparity, with the highest burden in African American patients. Even with effective screening tools such as colonoscopy and diagnostic detection assays, CRC remains a substantial health burden. In addition, primary tumors located in the proximal (right) or distal (left) sides of the colorectum have been shown to be unique tumor types that require unique treatment schema. Distal metastases in the liver and other organ systems are the major causes of mortality in CRC patients. Characterizing genomic, epigenomic, transcriptomic and proteomic (multi-omics) alterations has led to a better understanding of primary tumor biology, resulting in targeted therapeutic advancements. In this regard, molecular-based CRC subgroups have been developed that show correlations with patient outcomes. Molecular characterization of CRC metastases has highlighted similarities and differences between metastases and primary tumors; however, our understanding as to how to improve patient outcomes based on metastasis biology is lagging and remains a major obstacle to improving CRC patient outcomes. In this review, we will summarize the multi-omics features of primary CRC tumors and their metastases across racial and ethnic groups, the differences in proximal and distal tumor biology, molecular-based CRC subgroups, treatment strategies and challenges for improving patient outcomes.

Understanding health disparities affecting people of West Central African descent in the United States: An evolutionary perspective

Human populations adapting to diverse aspects of their environment such as climate and pathogens leave signatures of genetic variation. This principle may apply to people of West Central African descent in the United States, who are at increased risk of certain chronic conditions and diseases compared to their European counterparts. Less well known is that they are also at reduced risk of other diseases. While discriminatory practices in the United States continue to affect access to and the quality of healthcare, the health disparities affecting African Americans may also be due in part to evolutionary adaptations to the original environment of sub-Saharan Africa, which involved continuous exposure to the vectors of potentially lethal endemic tropical diseases. Evidence is presented that these organisms selectively absorb vitamin A from the host, and its use in parasite reproduction contributes to the signs and symptoms of the respective diseases. These evolutionary adaptations included (1) sequestering vitamin A away from the liver to other organs, to reduce accessibility to the invaders; and (2) reducing the metabolism and catabolism of vitamin A (vA), causing it to accumulate to subtoxic concentrations and weaken the organisms, thereby reducing the risk of severe disease. However, in the environment of North America, lacking vA-absorbing parasites and with a mainly dairy-based diet that is high in vA, this combination of factors is hypothesized to lead to the accumulation of vA and to increased sensitivity to vA as a toxin, which contribute to the health disparities affecting African Americans. vA toxicity is linked to numerous acute and chronic conditions via mitochondrial dysfunction and apoptosis. Subject to testing, the hypothesis suggests that the adoption of traditional or modified West Central African-style diets that are low in vA and high in vA-absorbing fiber hold promise for disease prevention and treatment, and as a population-based strategy for health maintenance and longevity.

Impact of the COVID-19 pandemic on breast, colorectal, lung, and prostate cancer stage at diagnosis according to race

PURPOSE

To determine if the COVID-19 pandemic has further exacerbated racial disparities in late-stage presentation of breast, colorectal, lung, and prostate cancers.

METHODS

We conducted a registry-based retrospective study of patients with newly reported diagnoses of breast, colorectal, lung, and prostate cancers between March 2019-June 2019 (pre-COVID-19) and March 2020-June 2020 (early-COVID-19). We compared the volume of new diagnoses and stage at presentation according to race between both periods.

RESULTS

During the study period, a total of 3528 patients had newly diagnosed cancer; 3304 of which had known disease stages and were included in the formal analyses. 467 (14.1%) were Blacks, and 2743 were (83%) Whites. 1216 (36.8%) had breast, 415 (12.6%) had colorectal, 827 (25%) had lung, and 846 (25.6%) had prostate cancers, respectively. The pre-COVID-19 period included 2120 (64.2%), and the early-COVID-19 period included 1184 (35.8%), representing a proportional 44.2% decline in the volume of new cases of breast, colorectal, lung, and prostate cancers, p < 0.0001. Pre-COVID-19, 16.8% were diagnosed with metastatic disease, versus 20.4% early-COVID-19, representing a proportional increase of 21.4% in the numbers of new cases with metastatic disease, p = 0.01. There was a non-significant proportional decline of 1.9% in Black patients diagnosed with non-metastatic breast, colorectal, lung, and prostate cancers early-COVID-19 (p = 0.71) and a non-significant proportional increase of 7% in Black patients diagnosed with metastatic disease (p = 0.71). Difference-in-difference analyses showed no statistically significant differences in metastatic presentation comparing Black to White patients.

CONCLUSION

While we identified substantial reductions in the volume of new cancer diagnoses and increases in metastatic presentations due to the COVID-19 pandemic, the impact was similar for White and Black patients.

Underutilization of Guideline-Recommended Mismatch Repair/Microsatellite Instability Biomarker Testing in Advanced Colorectal Cancer

BACKGROUND

In 2017, DNA mismatch repair/microsatellite instability (MMR/MSI) testing was nationally recommended for advanced colorectal cancers based on favorable immune checkpoint inhibitor responses among patients with MMR-deficient/MSI-high tumors.

METHODS

Patients ages ≥20-years-old presenting with stage IV colorectal adenocarcinoma from 2010 to 2017 were identified from the National Cancer Database. 2017 was the latest year with available testing utilization data. Patient, tumor, socioeconomic, and care setting characteristics were evaluated for association with upfront MMR/MSI testing in 2017 using multivariable logistic regression and average adjusted predicted probabilities (%AAP).

RESULTS

Among 72,830 stage IV colorectal cancers, upfront MMR/MSI testing levels increased from 16.4% in 2010 to 56.4% in 2017. For patients diagnosed in 2017 (i.e., following national recommendations, n = 10,022), testing levels were lower for older patients (Padj &lt; 0.001), and were independent of patients' race/ethnicity and insurance status. Patients from the poorest quartile of households received less testing [49.6%AAP, 99.9% confidence interval (CI) 45.5-53.7] than patients from the 3rd (56.9%AAP, 99.9% CI, 53.3-60.6; Padj &lt; 0.001) or 4th quartiles (57.6%AAP, 99.9% CI, 54.3-60.9; Padj &lt; 0.001). Although testing levels improved most at community programs, they remained lower in 2017 (46.6%AAP, 99.9% CI, 41.0-52.1) compared with academic/NCI-designated comprehensive cancer centers (62.8%AAP, 99.9% CI, 59.7-65.8; Padj &lt; 0.001).

CONCLUSIONS

Upfront MMR/MSI testing utilization for patients with advanced colorectal cancer has increased but there is still substantial need for optimization. Testing utilization disproportionately lagged for patients who were older, from the poorest quartile of households, or managed at community cancer programs.

IMPACT

Our findings indicate opportunities for improving rates of MMR/MSI testing and reporting, possibly through incorporation into quality control and accreditation metrics.

Identification of a glycolysis- and lactate-related gene signature for predicting prognosis, immune microenvironment, and drug candidates in colon adenocarcinoma

Background: Colon adenocarcinoma (COAD), a malignant gastrointestinal tumor, has the characteristics of high mortality and poor prognosis. Even in the presence of oxygen, the Warburg effect, a major metabolic hallmark of almost all cancer cells, is characterized by increased glycolysis and lactate fermentation, which supports biosynthesis and provides energy to sustain tumor cell growth and proliferation. However, a thorough investigation into glycolysis- and lactate-related genes and their association with COAD prognosis, immune cell infiltration, and drug candidates is currently lacking.

Methods: COAD patient data and glycolysis- and lactate-related genes were retrieved from The Cancer Genome Atlas (TCGA) and Gene Set Enrichment Analysis (GSEA) databases, respectively. After univariate Cox regression analysis, a nonnegative matrix factorization (NMF) algorithm was used to identify glycolysis- and lactate-related molecular subtypes. Least absolute shrinkage and selection operator (LASSO) Cox regression identified twelve glycolysis- and lactate-related genes (ADTRP, ALDOB, APOBEC1, ASCL2, CEACAM7, CLCA1, CTXN1, FLNA, NAT2, OLFM4, PTPRU, and SNCG) related to prognosis. The median risk score was employed to separate patients into high- and low-risk groups. The prognostic efficacy of the glycolysis- and lactate-related gene signature was assessed using Kaplan–Meier (KM) survival and receiver operating characteristic (ROC) curve analyses. The nomogram, calibration curves, decision curve analysis (DCA), and clinical impact curve (CIC) were employed to improve the clinical applicability of the prognostic signature. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed on differentially expressed genes (DEGs) from the high- and low-risk groups. Using CIBERSORT, ESTIMATE, and single-sample GSEA (ssGSEA) algorithms, the quantities and types of tumor-infiltrating immune cells were assessed. The tumor mutational burden (TMB) and cytolytic (CYT) activity scores were calculated between the high- and low-risk groups. Potential small-molecule agents were identified using the Connectivity Map (cMap) database and validated by molecular docking. To verify key core gene expression levels, quantitative real-time polymerase chain reaction (qRT–PCR) assays were conducted.

Results: We identified four distinct molecular subtypes of COAD. Cluster 2 had the best prognosis, and clusters 1 and 3 had poor prognoses. High-risk COAD patients exhibited considerably poorer overall survival (OS) than low-risk COAD patients. The nomogram precisely predicted patient OS, with acceptable discrimination and excellent calibration. GO and KEGG pathway enrichment analyses of DEGs revealed enrichment mainly in the “glycosaminoglycan binding,” “extracellular matrix,” “pancreatic secretion,” and “focal adhesion” pathways. Patients in the low-risk group exhibited a larger infiltration of memory CD4+ T cells and dendritic cells and a better prognosis than those in the high-risk group. The chemotherapeutic agent sensitivity of patients categorized by risk score varied significantly. We predicted six potential small-molecule agents binding to the core target of the glycolysis- and lactate-related gene signature. ALDOB and APOBEC1 mRNA expression was increased in COAD tissues, whereas CLCA1 and OLFM4 mRNA expression was increased in normal tissues.

Conclusion: In summary, we identified molecular subtypes of COAD and developed a glycolysis- and lactate-related gene signature with significant prognostic value, which benefits COAD patients by informing more precise and effective treatment decisions.

Temporal trends in Black-White disparities in cancer surgery and cancer-specific survival in the United States between 2007 and 2015

BACKGROUND

The American Society of Clinical Oncology (ASCO) has strived to address racial/ethnic disparities in cancer care since 2009. Surgery plays a pivotal role in cancer care; however, it is unclear whether and how racial/ethnic disparities in cancer surgery have changed over time.

METHODS

This cohort study included 1,113,256 White and Black cancer patients across 9 years (2007-2015) using patient data extracted from the Surveillance, Epidemiology, and End Results (SEER)-18 registries. Patient data were included from 2007 to adjust insurance status and by 2015 to obtain at least a 3-year survival follow-up (until 2018). The primary outcome was a surgical intervention. The secondary outcomes were the use of (neo)adjuvant chemotherapy and cancer-specific survival (CSS). Adjusted associations of the race (Black/White) with the outcomes were measured in each cancer type and year.

RESULTS

The gap between surgery rates for Black and White patients narrowed overall, from an adjusted odds ratio (aOR) of 0.621 (0.592-0.652) in 2007 to 0.734 (0.702-0.768) in 2015. However, the racial gap persisted in the surgery rates for lung, breast, prostate, esophageal, and ovarian cancers. In surgically treated patients with lymph node metastasis, Black patients with colorectal cancer (CRC) were less likely to receive (neo)adjuvant chemotherapy than White patients. Black patients undergoing surgery were more likely to have a worse CSS rate than White patients undergoing surgery. In breast cancer patients, the overall trend was narrow, but continuously present, with an adjusted hazard ratio (aHR) of 1.224 (1.278-1.173) in 2007 and 1.042 (1.132-0.96) in 2015.

CONCLUSIONS

Overall, progress has been made toward narrowing the Black-White gap in cancer surgical opportunity and survival. Future efforts should be directed toward those specific cancers for which the Black-White gap continues. Additionally, it is worth addressing the Black-White gap regarding the use of (neo)adjuvant chemotherapy for CRC treatment.

Racial Disparities in Colorectal Cancer Care for Black Patients: Barriers and Solutions

Racial disparities in colorectal cancer for Black patients have led to a significant mortality difference when compared to White patients, a gap which has remained to this day. These differences have been linked to poorer quality insurance and socioeconomic status in addition to lower access to high-quality health care resources, which are emblematic of systemic racial inequities. Disparities impact nearly every point along the colorectal cancer care continuum and include barriers to screening, surgical care, oncologic care, and surveillance. These critical faults are the driving forces behind the mortality difference Black patients face. Health care systems should strive to correct these disparities through both cultural competency at the provider level and public policy change at the national level.

Luteolin impacts deoxyribonucleic acid repair by modulating the mitogen-activated protein kinase pathway in colorectal cancer

This study aimed to investigate the effects of luteolin on colorectal cancer (CRC) and explore its underlying mechanism. HCT-116 and HT-29 cells were treated with luteolin, cisplatin, or selumetinib. The cell survival, cell proliferation, apoptosis and cell cycle distribution, and DNA damage were detected using Cell Counting Kit-8, colony formation, flow cytometry, and immunofluorescence staining analysis, respectively. Western blotting was used to detect the expression of apoptosis-related, cycle-related, DNA-damage-related, and mitogen-activated protein kinase (MAPK) pathway-related proteins. Luteolin showed inhibitory effects on cellular growth by reducing cell survival and proliferation, inducing apoptosis and DNA damage, and arresting the cell cycle in a concentration-dependent manner in HCT-116 and HT-29 cells. Meanwhile, luteolin increased the expression of pro-apoptotic proteins, p-CHK1 (central to the induction of cell cycle arrest), and DNA excision repair protein and decreased anti-apoptotic proteins, G2-M phase-related proteins, and DNA repair proteins. The combination of cisplatin and luteolin significantly decreased cell survival and increased the apoptosis rate of HCT-116 and HT-29 cells compared with cisplatin alone. Bioinformatic analysis using the Comparative Toxicogenomics Database and STITCH and MalaCards databases showed that the MAPK pathway is involved in the pharmacology of luteolin. Furthermore, western blotting demonstrated that luteolin plays an inhibitory role by suppressing the MAPK signaling pathway in CRC, which is enhanced when combined with selumetinib. Luteolin can also prevent tumourigenesis in CRC in vivo. In conclusion, luteolin suppressed cell proliferation, blocked the cell cycle, and induced DNA damage and apoptosis progression in CRC cells by mediating the MAPK pathway

Healthcare Disparities and Colorectal Cancer

Health care disparities are defined as health differences between groups that are avoidable, unnecessary, and unjust. Racial disparities in colorectal cancer mortality, particularly for Black patients, are well-described. Disparities in preventative measures, early detection, effective treatment, and posttreatment services contribute to these differences. Underlying these issues are patient, provider, health care system, and policy-level factors that lead to these disparities. Multilevel interventions designed to address each level of care can provide an effective means to mitigate these disparities.

Three Potential Tumor Markers Promote Metastasis and Recurrence of Colorectal Cancer by Regulating the Inflammatory Response: ADAM8, LYN, and S100A9

Metastasis and recurrence are major causes of colorectal cancer (CRC) death, but their molecular mechanisms are unclear. In this study, genes associated with CRC metastasis and recurrence were identified by weighted gene coexpression network analysis, selecting the top 25% most variant genes in the dataset GSE33113. By average linkage hierarchical clustering, a total of 21 modules were generated. One key module was identified as the most relevant to the prognosis of CRC. Gene Ontology analysis indicated that genes associated with tumor metastasis and recurrence in this module were significantly enriched in inflammatory biological functions. Functional analysis was performed on the key module, and candidate hub genes (ADAM8, LYN, and S100A9) were screened out by expression and survival analysis. In summary, the three core genes identified in this study could greatly improve our understanding of CRC metastasis and recurrence. The results also provide a theoretical basis for the use of three core genes (ADAM8, LYN, and S100A9) as a combined marker for early diagnosis, which could benefit CRC patients.

Impact of prognostic factor distributions on mortality disparities for socioeconomically disadvantaged cancer patients

PURPOSE

We aimed to assess whether differences in the distributions of prognostic factors explain reported mortality disparities between urban safety-net and Surveillance, Epidemiology, and End Results (SEER) cancer populations.

METHODS

We used data from SEER and a safety-net cancer center in Texas. Eligible patients were adults aged ≤64 years and diagnosed with first primary female breast, colorectal, or lung cancer between 2008 and 2016. We estimated crude and adjusted risk differences (RD) in 3- and 5-year all-cause mortality (1- and 3-year for lung cancer), where adjustment was based on entropy balancing weights that standardized the distribution of sociodemographic and tumor characteristics between the two populations.

RESULTS

Our study populations comprised 1914 safety-net patients and 389,709 SEER patients. For breast cancer, the crude 3- and 5-year mortality RDs between safety-net and SEER populations were 7.7% (95% confidence limits [CL]: 4.3%, 11%) and 11% (95% CL: 6.7%, 16%). Adjustment for measured prognostic factors reduced the mortality RDs (3-year adjusted RD = 0.049%, 95% CL: -2.6%, 2.6%; 5-year adjusted RD = 5.6%, 95% CL: -0.83%, 12%). We observed similar patterns for colorectal and lung cancer albeit less magnitude.

CONCLUSIONS

Sociodemographic and tumor characteristics may largely explain early mortality disparities between safety-net and SEER populations but not late mortality disparities.

Development and validation of prognostic model based on the analysis of autophagy-related genes in colon cancer

BACKGROUND

Autophagy, a process of self-digestion, is closely related to multiple biological processes of colon cancer. This study aimed to construct and evaluate prognostic signature of autophagy-related genes (ARGs) to predict overall survival (OS) in colon cancer patients.

MATERIALS AND METHODS

First, a total of 234 ARGs were downloaded via The Cancer Genome Atlas (TCGA) database. Based on the TCGA dataset, differentially expressed ARGs were identified in colon cancer. The univariate and multivariate Cox regression analysis was performed to screen prognostic ARGs to construct the prognostic model. The feasibility of the prognostic model was evaluated using receiver operating characteristic curves and Kaplan-Meier curves. A prognostic model integrating the gene signature with clinical parameters was established with a nomogram.

RESULTS

We developed an autophagy risk signature based on the 6 ARGs (ULK3, ATG101, MAP1LC3C, TSC1, DAPK1, and SERPINA1). The risk score was positively correlated with poor outcome and could independently predict prognosis. Furthermore, the autophagy-related signature could effectively reflect the levels of immune cell type fractions and indicate an immunosuppressive microenvironment.

CONCLUSION

We innovatively identified and validated 6 autophagy-related gene signature that can independently predict prognosis and reflect overall immune response intensity in the colon cancer microenvironment.

Disparities in Surgical Oncology: Management of Advanced Cancer

Significant variations in the patterns of care, incidence, and mortality rates of several common cancers have been noted. These disparities have been attributed to a complex interplay of factors, including genetic, environmental, and healthcare-related components. Within this review, primarily focusing on commonly occurring cancers (breast, lung, colorectal), we initially summarize the burden of these disparities with regard to incidence and screening patterns. We then explore the interaction between several proven genetic, epigenetic, and environmental influences that are known to contribute to these disparities.