Colorectal Cancer Outcomes Research Articles

Clinicopathologic Profile and Treatment Outcomes of Colorectal Cancer in Young Adults: A Multicenter Study From India.

Colorectal cancer (CRC) in young adults is a rising concern in developing countries such as India. This study investigates clinicopathologic profiles, treatment patterns, and outcomes of CRC in young adults, focusing on adolescent and young adult (AYA) CRC in a low- and middle-income country (LMIC). A retrospective registry study from January 2018 to December 2020 involved 126 young adults (age 40 years and younger) with CRC. Patient demographics, clinical features, tumor characteristics, treatment modalities, and survival outcomes were analyzed after obtaining institutional ethics committees' approval. Among 126 AYA patients, 62.70% had colon cancer and 37.30% had rectal cancer. Most patients (67%) were age 30-39 years, with no significant gender predisposition. Females had higher metastatic burden. Abdominal pain with obstruction features was common. Adenocarcinoma (65%) with signet ring differentiation (26%) suggested aggressive behavior. Limited access to molecular testing hindered mutation identification. Capecitabine-based chemotherapy was favored because of logistical constraints. Adjuvant therapy showed comparable recurrence-free survival in young adults and older patients. For localized colon cancer, the 2-year median progression-free survival was 74%, and for localized rectal cancer, it was 18 months. Palliative therapy resulted in a median overall survival of 33 months (95% CI, 18 to 47). Limited access to targeted agents affected treatment options, with only 27.5% of patients with metastatic disease receiving them. Chemotherapy was generally well tolerated, with hematologic side effect being most common. This collaborative study in an LMIC offers crucial insights into CRC in AYA patients in India. Differences in disease characteristics, treatment patterns, and limited access to targeted agents highlight the need for further research and resource allocation to improve outcomes in this population.

Post-diagnosis adiposity, physical activity, sedentary behaviour, dietary factors, supplement use and colorectal cancer prognosis: Global Cancer Update Programme (CUP Global) summary of evidence grading.

Based on the World Cancer Research Fund Global Cancer Update Programme, we performed systematic reviews and meta-analyses to investigate the association of post-diagnosis adiposity, physical activity, sedentary behaviour, and dietary factors with colorectal cancer prognosis. We searched PubMed and Embase until 28th February, 2022. An independent expert committee and expert panel graded the quality of evidence. A total of 167 unique publications were reviewed, and all but five were observational studies. The quality of the evidence was graded conservatively due to the high risk of several biases. There was evidence of non-linearity in the associations between body mass index and colorectal cancer prognosis. The associations appeared reverse J-shaped, and the quality of this evidence was graded as limited (likelihood of causality: limited-no conclusion). The evidence on recreational physical activity and lower risk of all-cause mortality (relative risk [RR] highest vs. lowest: 0.69, 95% confidence interval [CI]: 0.62-0.77) and recurrence/disease-free survival (RR: 0.80, 95% CI: 0.70-0.92) was graded as limited-suggestive. There was limited-suggestive evidence for the associations between healthy dietary and/or lifestyle patterns (including diets that comprised plant-based foods), intake of whole grains and coffee with lower risk of all-cause mortality, and between unhealthy dietary patterns and intake of sugary drinks with higher risk of all-cause mortality. The evidence for other exposures on colorectal cancer outcomes was sparse and graded as limited-no conclusion. Analyses were conducted excluding cancer patients with metastases without substantial changes in the findings. Well-designed intervention and cohort studies are needed to support the development of lifestyle recommendations for colorectal cancer patients.

Obesity and overweight are associated with worse survival in early-onset colorectal cancer

BackgroundObesity and its associated lifestyle are known risk factors for early-onset colorectal cancer and are associated with poor postoperative and survival outcomes in older patients. We aimed to investigate the impact of obesity on the outcomes of early-onset colorectal cancers. MethodsRetrospective review of all patients undergoing primary resection of colon or rectal adenocarcinoma at our institution between 2015–2022. Patients who had palliative resections, resections performed at another institution, appendiceal tumors, and were underweight were excluded. The primary endpoint was survival according to the patient's body mass index: normal weight (18–24.9 kg/m2), overweight (25–29.9 kg/m2), and obesity (≥30 kg/m2). Patient and tumor characteristics and survival were compared between the three groups. ResultsA total of 279 patients aged <50 years with colorectal cancer were treated at our hospital; 120 were excluded from the analysis for the following reasons: main treatment or primary resection performed at another hospital (n = 97), no resection/palliative resection (n = 23), or body mass index <18 kg/m2 (n = 2). Of these, 157 patients were included in the analysis; 61 (38.9%) were overweight and 45 (28.7%) had obesity. Except for a higher frequency of hypertension in the overweight (P = .062) and obese (P = .001) groups, no differences in patient or tumor characteristics were observed. Mean overall survival was 89 months with normal weight, 92 months with overweight, and 65 months with obesity (P = .032). Mean cancer-specific survival was 95 months with normal weight, 94 months with overweight, and 68 months with obesity (P = .018). No statistically significant difference in disease-free survival (75 vs 70 vs 59 months, P = .844) was seen. ConclusionIndividuals with early-onset colorectal cancer who are overweight or obese present with similar tumor characteristics and postoperative morbidity to patients with normal weight. However, obesity may have a detrimental impact on their survival. Addressing obesity as a modifiable risk factor might improve early-onset colorectal cancer prognosis.

"Too young to have this kind of diagnosis": A qualitative exploration of younger adults' experiences of colorectal cancer diagnosis.

Colorectal cancer (CRC) incidence is rising among adults under the age of 50 (early- or young-onset CRC). This population is more likely to have advanced-stage disease at diagnosis, suggesting their diagnostic pathway may be prolonged. To better understand factors influencing this pathway, this study explored patients' experiences of decision-making during a diagnosis of young-onset CRC. Semi-structured interviews were conducted with 17 participants with young-onset CRC diagnosed in 2021-2022 in Victoria, Australia. Interviews were conducted online or by phone an average 7months (range 1-13) after diagnosis. Analysis was approached from a critical realist perspective, with themes developed inductively using reflexive thematic analysis. Five themes were identified: Shifting Perception of Urgency, Multidimensional Perception of Role, Making the Most of Resources, Stage of Life, and COVID Adds Complexity. Participants' decision-making evolved over the diagnostic period. As participants perceived urgency to act, they took on a more active role in decision-making, utilising personal resources to access timely care. Their decisions were shaped by stage-of-life considerations, including employment and caring for a young family, with the COVID-19 pandemic adding "…a whole other layer of complexity" to the process. Younger adults with CRC make decisions in the context of unique considerations, adapting to reduce time to diagnosis, with decisions complicated by the COVID-19 pandemic. Greater support from health care providers/systems in the diagnostic period may improve timeliness of CRC diagnosis and outcomes in younger adults.

Colorectal Cancer Screening in Free Clinics: A Systematic Review

Abstract: Objective. There are significant inequities in colorectal cancer (CRC) screening and outcomes. Via literature review, we assessed CRC screening rates for the vulnerable populations served by free clinics. Methods. A systematic review was conducted for publications on CRC screening in free clinics. Outcomes included CRC screening characteristics, population demographics, and limitations. A methodological quality assessment was completed. Results. Out of 63 references, six studies were included, representing 8,844 participants. Black or Hispanic participants were the plurality in all but one study. All participants were uninsured. Median CRC screening rate was 48.4% (range 6.6–78.9%). Screening methods included colonoscopy, fecal occult blood test, flexible sigmoidoscopy, and fecal immunochemical test. Clinics offering only one screening method had a mean screening rate of 7.2% while those with multiple methods had a screening rate of 65.4%. Conclusion. Access to multiple CRC screening modalities correlates with higher screening rates in free clinics. More work is needed to increase CRC screening in free clinics.

Colorectal Cancer Stem Cell Biomarkers: Biological Traits and Prognostic Insights.

Due to self-renewal, differentiation, and limitless proliferation properties, Cancer Stem Cells (CSCs) increase the probability of tumor development. These cells are identified by using CSC markers, which are highly expressed proteins on the cell surface of CSCs. Recently, the therapeutic application of CSCs as novel biomarkers improved both the prognosis and diagnosis outcome of colorectal Cancer. In the present review, we focused on a specific panel of colorectal CSC markers, including LGR5, ALDH, CD166, CD133, and CD44, which offers a targeted and comprehensive analysis of their functions. The selection criteria for these markers cancer were based on their established significance in Colorectal Cancer (CRC) pathogenesis and clinical outcomes, providing novel insights into the CSC biology of CRC. Through this approach, we aim to elevate understanding and stimulate further research for developing effective diagnostic and therapeutic strategies in CRC.

Canadian colorectal cancer screening programs: How do they measure up using the International Agency for Research on Cancer criteria for organized screening?

Canada has one of the highest incidences of colorectal cancer (CRC) worldwide. CRC screening improves CRC outcomes and is cost-effective. This study compares Canadian CRC screening programs using essential elements of an organized screening program outlined by the International Agency for Research on Cancer (IARC). We collaborated with the Cancer Screening in 5 continents (CanScreen5) program, an initiative of IARC. Standardized data collection forms were sent to representatives of provincial and territorial CRC screening programs. Twenty-five questions were selected to reflect IARC's essential elements of an organized screening program. We performed a qualitative analysis of Canada's CRC screening programs and compared programs within Canada and internationally. CRC screening programs exist in 10 provinces and 2 territories. None of the programs in Canada met all the essential criteria of an organized screening program outlined by IARC. Three programs do not send invitations to participate in screening. Among those that do, 4 programs do not include a stool test kit in the invitations. While all provinces met the essential elements for leadership, governance, finance, and access to essential services, there was more heterogeneity in the domains of service delivery as well as information systems and quality assurance. There is considerable heterogeneity in the design of CRC screening programs in Canada and worldwide. Programs should strive to meet all the essential IARC criteria for organized screening if local resources allow, such as issuing invitations and implementing systems to track and compare outcomes to maximize screening program quality, effectiveness, and impact.

Estimated impact and value of blood-based colorectal cancer screening at varied adherence compared with stool-based screening

Objective This analysis estimated the outcomes of triennial blood-based colorectal cancer (CRC) screening at various adherence, including perfect adherence, compared with triennial multi-target stool DNA (mt-sDNA) screening at the reported real-world adherence rate. Methods The validated CRC-AIM model simulated a US cohort of average-risk individuals receiving triennial screening with mt-sDNA or blood-based test from ages 45 to 75 years. Modeled specificity and sensitivity were based on reported data. Adherence was set at a real-world rate of 65.6% for mt-sDNA and at 65.6%, relative 10% incremental increases from 65.6%, or 100% for the blood-based test. Costs of mt-sDNA and the blood-based test were based on prices for clinically available tests ($508.87 and $895, respectively). Value-based pricing was estimated at a willingness-to-pay threshold of $100,000. Results Both tests resulted in life-years gained (LYG), reduced CRC cases, and reduced deaths versus no screening. With adherence for mt-sDNA set at 65.6% and for blood-based test set at 100%, mt-sDNA resulted in 30% more LYG, 52% more averted CRC cases, and 32% more averted CRC deaths. At reported sensitivity and specificity rates, mt-sDNA at 65.6% adherence dominates (is more effective and less costly) the blood-based test at any adherence. There was no price at which triennial screening with the blood-based test at any adherence was cost-effective compared with mt-sDNA at 65.6% adherence. Conclusions Triennial screening with mt-sDNA resulted in better clinical outcomes at a lower cost compared with the modeled blood-based test even at perfect adherence, supporting application of blood-based tests only as a secondary screening option.

Exploring the prognostic significance of iron death‑related lncRNAs in colorectal cancer: A systematic review and meta‑analysis.

Colorectal cancer is a significant health challenge globally, with its prognosis associated with the profile of molecular biomarkers. Recently, the role of iron death-associated long non-coding (lnc)RNAs in cancer development has garnered attention; however, their expression patterns and prognostic value in colorectal cancer remain poorly elucidated. The present study aimed to assess the expression levels of iron death-related lncRNAs in colorectal cancer tissues and evaluate their relationship with patient outcomes through a comprehensive meta-analysis. Systematic searches were performed across multiple databases, including PubMed, Embase, Web of Science, Cochrane Library, CNKI, Wanfang and VIP databases, to identify studies relevant to the objective of the present study. Selected studies met predetermined inclusion criteria, from which data were extracted. R software version 4.3.1 was used for the meta-analysis, evaluating the association between iron death-related lncRNAs expression and colorectal cancer prognosis. Publication bias was assessed using funnel plot analysis, and Begg's and Egger's test. A total of 11 studies, including 3,984 patients with colorectal cancer, were included in the present meta-analysis. The results demonstrated a significant association between iron death-related lncRNAs and tumor stage classification [odds ratio (OR)=2.00; 95% confidence interval (CI), 1.77-2.24]. Notably, a significant association was also revealed between iron death-related lncRNAs and T stage classification in colorectal cancer (OR=1.82; 95% CI, 1.50-2.20). Furthermore, a statistically significant association was demonstrated between iron death-related lncRNAs and lymph node metastasis in colorectal cancer (OR=1.31; 95% CI, 1.03-1.66). The findings also highlighted a significant association between iron death-associated lncRNA and distant metastasis in colon cancer (OR=2.04; 95% CI, 1.62-2.56). Moreover, a significant association between iron death-related lncRNAs and risk score in colorectal cancer was revealed (OR=1.75; 95% CI, 1.25-2.46). In conclusion, the findings of the present meta-analysis underscore the potential of high ferroptosis-associated lncRNA expression as an indicator of adverse outcomes in colorectal cancer, suggesting their viability as biomarkers for cancer progression and prognosis. This insight opens potential new avenues for clinical application and further research into colorectal cancer management.

Histopathological tumour microenvironment score independently predicts outcome in primary operable colorectal cancer.

Colorectal cancer (CRC) is a heterogenous malignancy and research is focused on identifying novel ways to subtype patients. In this study, a novel classification system, tumour microenvironment score (TMS), was devised based on Klintrup-Mäkinen grade (KMG), tumour stroma percentage (TSP), and tumour budding. TMS was performed using a haematoxylin and eosin (H&E)-stained section from retrospective CRC discovery and validation cohorts (n = 1,030, n = 787). TMS0 patients had high KMG, TMS1 were low for KMG, TSP, and budding, TMS2 were high for budding, or TSP and TMS3 were high for TSP and budding. Scores were assessed for association with survival and clinicopathological characteristics. Mutational landscaping and Templated Oligo-Sequencing (TempO-Seq) profiling were performed to establish differences in the underlying biology of TMS. TMS was independently prognostic in both cohorts (p < 0.001, p < 0.001), with TMS3 predictive of the shortest survival times. TMS3 was associated with adverse clinical features including sidedness, local and distant recurrence, higher T stage, higher N stage, and presence of margin involvement. Gene set enrichment analysis of TempO-Seq data showed higher expression of genes associated with hallmarks of cancer pathways including epithelial to mesenchymal transition (p < 0.001), IL2 STAT5 signalling (p = 0.007), and angiogenesis (p = 0.017) in TMS3. Additionally, enrichment of immunosuppressive immune signatures was associated with TMS3 classification. In conclusion, TMS represents a novel and clinically relevant method for subtyping CRC patients from a single H&E-stained tumour section.

Trends and disparities in colorectal cancer hospitalizations and outcomes: a 10-year joinpoint trend study

Background Colorectal cancer (CRC) poses a significant burden on healthcare systems globally. Sociodemographic factors intricately influence CRC epidemiology, yet their impact on inpatient care remains underexplored. This study aimed to assess trends in CRC hospitalization and the effect of sociodemographic factors on outcomes of CRC patients. Methods A retrospective longitudinal analysis was conducted using data from the Healthcare Cost and Utilization Project National Inpatient Sample. Trends in CRC admissions were assessed, stratified by sociodemographic variables. Disparities in hospital-associated outcomes were examined. Statistical methods included multivariable regression and joinpoint regression analysis. Results The prevalence of CRC hospitalizations uptrended from 760 per 100,000 hospitalizations in 2010 to 841 per 100,000 hospitalizations in 2019 (P trend < 0.001). The mean age decreased from 67 to 66 years (P < 0.001). Male gender and White race were predominant across the study period. Inpatient mortality decreased from 4.5% in 2010 to 4.16% in 2019 (P trend = 0.033). On sex subgroup analysis, men had a significantly higher mortality rate (P = 0.034). Racially, Blacks had the highest mortality rate (P = 0.550) and only Whites showed a significant decline in mortality over the study period (P = 0.003). Hospitalization length decreased while total hospital charges increased. Conclusion Our study highlights sociodemographic disparities in CRC outcomes, emphasizing the need for targeted interventions to address inequity in screening, diagnosis, and treatment. Continued research is needed to inform effective healthcare practices in mitigating these disparities and improving survival outcomes.

Evaluation of Stages, Treatment Protocols, and Outcomes of Colorectal Cancer among West Bank Patients.

Background: Colorectal cancer (CRC) is the second most widespread cancer among Palestinian patients. As cancer care improves in hospitals across the West Bank, services like palliative care, targeted therapy, bone marrow transplantation, and individualized therapy are still limited. This study aimed to assess the CRC stages, treatment protocols, and survival rates of patients in the West Bank. Methodology: This retrospective study collected data from the medical records of Al-Najah University Hospital (NUH), which specializes in the care of cancer patients. Patients with confirmed CRC (stages I-IV) undergoing surgical or medical treatment were included in the study. Data collection was standardized by using a data collection form to gather information from the medical records included in the study. All statistical analyses were performed using SPSS (version v27), and survival was assessed using a regression analysis of the number of days from the time of diagnosis to the most recent visit against the type of treatment (e.g., surgery, chemotherapy, radiotherapy). Results: A sample of 252 patients with CRC from NUH was collected, including 143 males and 109 females aged between 27 and 86 years, with the average age being 60.6 ± 11.4 years. The sample included 183 patients (72.6%) diagnosed with colon cancer only, 29 patients (11.5%) diagnosed with rectal cancer only, and 40 patients (15.9%) diagnosed with both. Diagnosis took place at CRC stage I for 3 patients (1.2%), stage II for 33 patients (13.1%), stage III for 57 patients (22.6%), and stage IV for 159 patients (63.1%). Surgery was the most prevailing mode of treatment for 230 patients (91.3%), while 227 patients (90.1%) received chemotherapy treatment, and 38 patients (15.1%) received radiotherapy. Of the 252 patients, 40 patients (15.8%) received FOLFOX (i.e., folinic acid, fluorouracil, oxaliplatin), and 25 patients (9.9%) received FOLFIRI (i.e., folinic acid, fluorouracil, irinotecan), while the 187 remaining patients (74.2%) were treated with capecitabine, oxaliplatin, bevacizumab, cetuximab, regorafenib, cisplatin, etoposide, gemcitabine, or a combination thereof. The sample was categorized into six outcomes: (1) death, (2) cure, (3) disease progression, (4) disease recurrence, (5) under-treatment, and (6) unknown. Mortality was high, with 104 patients (41.3%) dying within a short time after diagnosis, and may have been attributable to delayed diagnosis. Surgical treatment had a positive impact on increasing the survival years, and it was significant (p = 0.033). Conclusions: A high percentage of patients were diagnosed in advanced CRC stages. The treatment modes were adopted from general international guidelines; however, the cure rates were low, and mortality was high. More studies need to be undertaken to investigate the actual application of chemotherapy protocols, and survival would benefit from the involvement of clinical pharmacists in the chemotherapy protocol selection, dosing, frequency, and follow-up. The present study advocates for greater public awareness of CRC and attests to the merits of screening by primary care professionals, which can help to avoid this serious illness and to promote a better prognosis.

Race/Ethnicity and Social Determinants of Health and Their Impact on Receiving Appropriate Chemotherapy for Colon Cancer.

Despite the heightened understanding and improved treatment for colorectal cancer in the United States, social determinants of health (SDH) play a significant role in the colorectal cancer outcomes. We sought to investigate the relationship between SDH and appropriate utilization of adjuvant chemotherapy in stage III colon cancer. For this retrospective study, we utilized data from the National Cancer Data Base (NCDB). Descriptive statistics are reported, including means and 95% confidence intervals for continuous variables and frequency and proportions for categorical variables. Univariate hypothesis testing to identify categorical level factors associated with treatment used Wilcoxon rank sum or Kruskal-Wallis tests, with multivariate analyses performed using regression analysis. Significant differences were as follows: Metro-non-Hispanic White patients received treatment less frequently (69.7%) when compared to Metro-non-Hispanic Black patients (73.4%) (P < .001). Increasing age was a negative predictor of likelihood to receive with those over 65years old having an 83% decrease in likelihood to receive chemotherapy when compared to those under 65 (P < .001). Medicaid patients were 47% less likely and Medicare patients were 40% less likely to receive chemotherapy when compared to those with private insurance (P < .001). Rural patients were statistically more likely to receive chemotherapy (OR 1.42, 1.32-2.52, P < .001) as were urban patients, (OR 1.26, 1.20-1.31, P < .001) when compared to patients residing in metro areas. Age, living in a Metro area, and government insurance status at diagnosis are negatively correlated with the likelihood of receiving chemotherapy. Race was not associated with differences in receiving chemotherapy.

Abstract LB386: Weakly-supervised prediction of tumor infiltrating lymphocytes per high power field from colorectal cancer histopathology slides using regression transformers

Abstract Tumor infiltrating lymphocytes (TILs)-based biomarkers have emerged as a robust method for predicting treatment efficacy and outcome in colorectal cancer (CRC). However, the quantification of TILs remains a strenuous task for pathologists and is susceptible to inter-pathologist variations. Deep learning (DL) can predict cancer biomarkers directly from routine hematoxylin and eosin (H&amp;E) pathology slides, enabling the automated and consistent quantification of TILs for clinical decision-making. Our study focuses on the prediction of TILs per high-power field (HPF) on two large cohorts of CRC patients. We developed a weakly-supervised, transformer-based deep regression model to predict TILs per HPF from routine H&amp;E-stained histology slides. We trained the model using 5-fold cross-validation on a large cohort of CRC patients (n=1,738), and validated its performance on an external cohort of CRC patients (n=223). The model was evaluated using the Pearson’s correlation coefficient r. Moreover, pathologist-determined TILs per HPF was categorized into low (&amp;lt;2) and high (≥2), enabling evaluation via the area under the receiver operating characteristic curve (AUROC). Our model achieved a significant correlation coefficient of 0.60 (p&amp;lt;0.0001) for the predicted TILs per HPF in the holdout test sets of the internal cohort, and a significant correlation coefficient of 0.57 (p&amp;lt;0.0001) on the external validation cohort. Using the thresholds for low and high TILs per HPF, we found that the model accurately predicted the presence of high TILs per HPF in both the internal and external test cohorts, yielding AUROCs of 0.76 and 0.81, respectively. These findings underscore the efficacy of our deep learning model in predicting TILs per HPF from routine pathology slides. This approach holds promise for cost-effective, efficient and uniform quantification of TILs per HPF in CRC, potentially across various cancer types. Citation Format: Omar S. El Nahhas, Joseph D. Bonner, Joel K. Greenson, Daniel B. Schmolze, Lawrence Shaktah, Jonathan Salazar, Lorena Reynaga, Sidney Lindsey, Jenny Lu, Victor Moreno, Stephanie L. Schmit, Ya-Yu Tsai, Stanley R. Hamilton, Gad Rennert, Jakob N. Kather, Stephen B. Gruber. Weakly-supervised prediction of tumor infiltrating lymphocytes per high power field from colorectal cancer histopathology slides using regression transformers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB386.

Integrating transcriptomics and machine learning for immunotherapy assessment in colorectal cancer

Colorectal cancer (CRC) is a highly prevalent and lethal malignancy worldwide. Although immunotherapy has substantially improved CRC outcomes, intolerance remains a major concern among most patients. Considering the pivotal role of the tumor microenvironment (TME) in tumor progression and treatment outcomes, profiling the TME at the transcriptomic level can provide novel insights for developing CRC treatment strategies. Seventy-seven TME-associated signatures were acquired from previous studies. To elucidate variations in prognosis, clinical features, genomic alterations, and responses to immunotherapy in CRC, we employed a non-negative matrix factorization algorithm to categorize 2595 CRC samples of 27 microarrays from the Gene Expression Omnibus database. Three machine learning techniques were employed to identify a signature specific to immunotherapy. Subsequently, the mechanisms by which this signature interacts with TME subtypes and immunotherapy were investigated. Our findings revealed five distinct TME subtypes (TMESs; TMES1–TMES5) in CRC, each exhibiting a unique pattern of immunotherapy response. TMES1, TMES4, and TMES5 had relatively inferior outcomes, TMES2 was associated with the poorest prognosis, and TMES3 had a superior outcome. Subsequent investigations revealed that activated dendritic cells could enhance the immunotherapy response rate, with their augmentation effect closely associated with the activation of CD8+T cells. We successfully classified CRC into five TMESs, each demonstrating varying response rates to immunotherapy. Notably, the application of machine learning to identify activated dendritic cells helped elucidate the underlying mechanisms contributing to these differences. We posit that these TMESs hold promising clinical implications for prognostic evaluation and guidance of immunotherapy strategies, thereby providing valuable insights to inform clinical decision-making.

Association of Preoperative and Postoperative Plasma Syndecan-1 and Colorectal Cancer Outcome.

A three-dimensional network constructed using glycocalyx (GCX) extends throughout the cancer cell nest in human colorectal cancer (CRC). GCX was found to be closely related to cancer. We examined the prognostic correlation and potential of syndecan-1 (SDC1), a representative proteoglycan of GCX, as a biomarker. We analyzed SDC1 in the transcriptomic profiles of a major publicly available CRC cohort from The Cancer Genome Atlas (TCGA) using a computational algorithm. We investigated serum SDC1 levels preoperatively and on postoperative day seven in 48 patients with stage I-III CRC who underwent surgery during July-December 2019 at Gifu University Hospital. For TCGA, no significant differences existed between the high and low SDC1 expression groups regarding disease-free, disease-specific, and overall survival for stage I-III, and only overall survival for stage IV was significantly different. In our study, among the 48 patients, 17 (no recurrence), 13 (1 recurrence), and 18 (10 recurrences) had stage I-III, respectively. Preoperative and postoperative day 7 SDC1 levels for patients with stage I-III were 10.7±2.3 and 9.9±3.1 ng/ml (p=0.40), 11.1±1.7 and 10.1±0.8 ng/ml (p=0.07), and 10.3±2.0 and 9.5±1.4 ng/ml (p=0.15), respectively. In stage II and III, patients were divided into two groups according to differences between preoperative and postoperative SDC1 levels (SDC1pre-pro). SDC1pre-pro ≤0 group significantly prolonged disease-free survival compared with SDC1pre-pro >0 group (p=0.048). Dynamic change in serum SDC1 levels serves as a prognostic biomarker for stage II and III colorectal cancer.

Abstract 578: Prediction of PD-1 treatment outcome in mismatch repair deficient metastatic colorectal cancer using a multi-omic approach

Abstract Background: Immune checkpoint inhibitors (ICIs) have revolutionized the treatment of patients with deficient DNA mismatch repair (d-MMR) cancers, yet less than half of patients with metastatic colorectal cancer (mCRC) receive clinical benefit. We analyzed heterogeneity within d-MMR tumors using a multi-omics approach inclusive of percent unstable microsatellite loci (MS). Methods: We studied consecutive patients with d-MMR mCRC with available primary tumors (N=32) that were treated with an anti-PD-1 antibody at Mayo Clinic (2015-2022). Tumors were profiled using a whole exome and transcriptome platform (ImmunoID NeXT®). MSIsensor was used to calculate percent unstable microsatellite loci from whole exome sequencing data. CIBERSORT and ssGSEA were used to analyze immune gene expression in relationship to percent unstable microsatellite loci. An immune checkpoint gene expression signature was calculated as the mean expression of CD274, CTLA-4, HAVCR2, LAG-3, PDCD1, PDCD1LG2, TIGIT. Aforementioned variables were analyzed in relationship to objective tumor response (RECIST version 1.1). A Cox proportional hazards model was fit to predict progression-free survival (PFS). Results: Among 32 patients with d-MMR mCRC treated with PD-1 blockade, 16 (50%) received first-line anti-PD-1 therapy; others had &amp;gt; 1 prior chemotherapy regimen. Eighteen (56.3%) tumors harbored BRAFV600E, 4 (12.5%) had mutant KRAS, and median PFS was 24.6 months (95% CI: 8.4, NR) with 18 events. Neither tumor mutation burden (TMB) nor PD-L1 mRNA expression predicted PFS. Median percent unstable MS loci was 14.38 (IQR: 2.6-23.2). Patients whose tumors had higher percent unstable MS loci had significantly better PFS (Q2-4 vs Q1; HR: 0.22, 95%CI: 0.06, 0.62; P=0.003), and were associated with increased objective response (P=0.049). Tumors with higher unstable loci also had higher neoantigen clonality (R= 0.64; P= 0.0003) and increased M0 (resting) macrophages (P=0.02). Nonresponders (vs responders) to PD-1 blockade had an increased immune checkpoint expression signature (P= 0.005). Conclusion: A higher percentage of unstable microsatellite loci, associated with higher neoantigen clonality and resting macrophages, was predictive of anti-PD-1 efficacy. Furthermore, an immune checkpoint gene expression signature was associated with objective response. Citation Format: Bahar Saberzadeh-Ardestani, Oluwadunni E. Emiloju, Rondell P. Graham, Jason T. Lewis, Charles W. Abbott, Sean M. Boyle, Frank A. Sinicrope. Prediction of PD-1 treatment outcome in mismatch repair deficient metastatic colorectal cancer using a multi-omic approach [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 578.

Abstract 6109: Determinants of generalized self-efficacy and genetic knowledge among Hispanic/Latino colorectal cancer patients participating in ENLACE: A Cancer Moonshot Study

Abstract Background: Colorectal cancer (CRC) is the third most common cancer, and second cause of cancer death in the United States (US). Among US Hispanic/Latino/a/x (H/L) individuals, CRC represents the second and the third most common cancer and the most common cause of cancer death for men and women, respectively. Despite this, the tumor landscape, and key determinants of outcomes in CRC H/L patients are understudied. Methods: To address this need, we launched the ENLACE study, to engage H/L CRC patients in germline and somatic sequencing and identify the optimal approaches for patient participation. Through the Center for Patient Engagement in Cancer Characterization Studies (COPECC) patients were recruited from two healthcare facilities: a safety-net hospital (Los Angeles General Medical Center, LA Gen) and the USC Norris Comprehensive Cancer Center (Norris) a university medical center. Surveys to assess demographics, acculturation, Latino values, health literacy, discrimination, health system distrust, numeracy, and generalized self-efficacy (GSE) were evaluated upon recruitment, and after return-of-results (ROR) for somatic and germline testing. Results: After the first year of the project, a total of 100 H/L CRC patients &amp;gt;18 years of age were included in the ENLACE study, 89 participants completed baseline surveys (49 female, median age 53 (IQR = 16) and 21 completed questionnaires after ROR. A majority self-identified as White (61%), Mexico born (51%), catholic (74%), only spoke Spanish at home (35%) and married (49%). Higher levels of GSE were reported in patients with higher scores for numeracy (p = 0.005) and in males when compared to females (p = 0.016). This association was driven by participants from Norris (n=33) as reported by stratified analyses. In contrast, among participants from LA Gen (n=66) we observed an association with higher median values for the Mexican American acculturation scale and mainstream values and a marginally significant increase in the GSE (p = 0.072 &amp; 0.083, respectively). Additionally, LA Gen participants with a greater than the median score for GSE had a marginally significant higher mean score in the KnowGene scale (p = 0.056) with a reduction in the number of times the “Don’t Know” option was selected (p = 0.045). No statistically significant difference in the generalized self-efficacy score and KnowGene scale were reported after reception of results (p = 0.2386 &amp; 0.1337, respectively) Conclusion: We report differences in GSE and cancer genetic knowledge amongst CRC H/L patients in the ENLACE study that may inform understanding of disparities and social determinants in the populations treated at two different healthcare facilities. Citation Format: Joel Sanchez Mendez, Julie O. Culver, Charité N. Ricker, Natalia Gutierrez, Sandra Algaze, John D. Carpten, Heinz-Josef Lenz, Mariana C. Stern. Determinants of generalized self-efficacy and genetic knowledge among Hispanic/Latino colorectal cancer patients participating in ENLACE: A Cancer Moonshot Study [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6109.

Abstract 2784: Fatty acid synthase enhances stem-like properties of normal intestinal and colorectal cancer cells via an increase in notum expression and secretion

Abstract Introduction: Overexpression of lipogenic enzymes has been associated with a poor clinical outcome in colorectal cancer (CRC). Fatty acid synthase (FASN) synthesizes palmitate which can be utilized for post-translational modifications of various proteins. Notum, a palmitoleoyl-protein, prevents the downstream activation of Wnt signaling by de-palmitoylating Wnt ligands. Notum is also a CRC stem cell marker, and its expression correlates with poor prognosis in CRC. We found that upregulation of FASN is associated with an increase in Notum expression in mouse adenoma tissues. Therefore, the purpose of this study is to elucidate the mechanisms and contribution of FASN/Notum axis in CRC. Methods: Adenoma and normal intestinal organoids, established from ApcMin/VillinCre-ERT2 and Apc/VillinCre-ERT2 mouse models with hetero- and homozygous deletion of FASN. 4-hydroxytamoxifen (4-OHT) and TVB-3664 (FASN inhibitor) treatments were used to assess the effect of FASN deletion/inhibition on organoid growth and viability. LIVE/DEAD™ Viability/Cytotoxicity and Cell Titer-Glo® 3D Cell Viability Assays were used for quantitative analysis of growth. Human NOTUM/Protein notum homolog ELISA Kit was used to analyze Notum secretion. CRC cells, NTC and FASN shRNA, and control and FASN overexpression, were used for Notum analysis. Results: The TCGA data analysis shows that Notum is significantly upregulated in CRC and its expression correlates with expression of FASN in tumor tissue. Utilizing qRT-PCR and Western blot analyses, we show that downregulation of FASN leads to a decrease in expressions of active β-catenin, Notum, and other stem cell markers in transgenic mouse models. Moreover, 4-OHT-mediated inhibition of FASN results in decrease viability and size in ApcMin/FASN/VillinCre-ERT2 and Apc/FASN/VillinCre-ERT2 organoids. Consistently, shRNA-mediated deletion of FASN decreases expression of Notum in CRC cells. In contrast, overexpression of FASN increases the expression levels of active and total β-catenin, Notum, and other stem cell markers in SW480 cells. We show that normal epithelial cells exposed to CRC cell medium exhibit stem-like phenotype which is reduced when cells are exposed to medium collected from Notum shRNA knockdown cells. Moreover, the addition of recombinant Notum restores this phenotype. Conclusion: In summary, downregulation of FASN leads to a decrease in expression of Notum and is associated with morphological changes and significant decrease in viability in organoid models. Conversely, FASN overexpression upregulates Notum expression suggesting a potential cross talk between de novo lipid synthesis and Notum. Delineating the role of FASN regulation of stem-like properties via upregulation of β-catenin signaling and expression of Notum and other stem cell markers will provide the rationale for targeting the FASN/Notum axis in CRC. Citation Format: Courtney Olivia Kelson, Josiane Weber Tessmann, Daheng He, Chi Wang, Yekaterina Zaytseva. Fatty acid synthase enhances stem-like properties of normal intestinal and colorectal cancer cells via an increase in notum expression and secretion [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2784.

Abstract 1282: Gavage with Candida albicans leads to fungal colonization of colorectal tumors and decreased response to radiotherapy

Abstract The host microbiome in the gut and tumors have been shown to affect tumor growth and therapeutic response in cancer. Furthermore, the presence of specific fungal taxa are associated with tumor hypoxia, tumor progression, therapeutic response, and clinical outcomes in colorectal cancer (CRC). Preliminary data from our group found that the presence of Candida species increased tumor hypoxia and decreased overall survival in CRC. However, whether intratumoral Candida drive, support, or simply inhabit tumors with poor prognoses remains unclear. Here, we investigate a casual role for Candida albicans in tumor progression and therapy response using a syngeneic mouse model of microsatellite-instability high (MSI-H) colorectal cancer. We subcutaneously implanted MC38 colorectal cancer cells into C57BL/6 mice and then orally gavaged these mice with C. albicans, Saccharomyces cerevisiae, or PBS. The site of tumor formation was locally irradiated once (7.5 Gy), and growth of the tumor was measured over time. Differences in tumor volume were assessed by longitudinal mixed-effect models. Tumor sections were stained for fungi using calcofluor white (CFW) and underwent bulk RNA sequencing to detect differential gene expression, which were interpreted using gene set enrichment analysis (GSEA). Mice gavaged with C. albicans showed decreased response to radiation compared to mice gavaged with either S. cerevisiae (p&amp;lt;0.05) or PBS (p&amp;lt;0.001). Additionally, hyphae were observed in murine tumors gavaged with C. albicans, suggesting translocation of gavaged C. albicans from the gut to tumors. Further, tumors from mice gavaged with C. albicans displayed unique gene expression profiles, including decreased interferon alpha and IL-6 and STAT3 signaling, decreased oxidative phosphorylation, and decreased apoptosis-related gene expression. Here, we show that C. albicans may confer resistance to radiation therapy and affects immune and cancer cell activity in the MC38 (MSI-H) syngeneic in vivo model of colorectal cancer. Further, we show that hyphal fungi can be visualized in heterotopic murine tumors from our C. albicans gavage condition. These data establish that fungi can translocate from the gut to distal tumor sites, and that upon translocation, changes in gene expression and therapy response are observed. Future directions will explore the mechanism by which these effects occur and whether these findings can be leveraged to improve radiotherapy outcomes. Citation Format: Dennis J. Grencewicz, Alexander Loncar, Rebecca Hoyd, Aaditya Pallerla, Nyelia Williams, Martin Benej, McKenzie Kreamer, Yogita Mehra, Shiva Jahanbakhshi, Matthew Anderson, Nicholas Denko, Daniel Spakowicz. Gavage with Candida albicans leads to fungal colonization of colorectal tumors and decreased response to radiotherapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1282.