Colorectal cancer statistics, 2023

Colorectal Cancer: Epidemiology, Risk Factors, and Prevention

Colorectal cancer (CRC) is the third most common cancer and the second most common cause of cancer mortality worldwide. There are disparities in the epidemiology of CRC across different populations, most probably due to differences in exposure to lifestyle and environmental factors related to CRC. Prevention is the most effective method for controlling CRC. Primary prevention includes determining and avoiding modifiable risk factors (e.g., alcohol consumption, smoking, and dietary factors) as well as increasing protective factors (e.g., physical activity, aspirin). Further studies, especially randomized, controlled trials, are needed to clarify the association between CRC incidence and exposure to different risk factors or protective factors. Detection and removal of precancerous colorectal lesions is also an effective strategy for controlling CRC. Multiple factors, both at the individual and community levels (e.g., patient preferences, availability of screening modalities, costs, benefits, and adverse events), should be taken into account in designing and implementing CRC screening programs. Health policymakers should consider the best decision in identifying the starting age and selection of the most effective screening strategies for the target population. This review aims to present updated evidence on the epidemiology, risk factors, and prevention of CRC.

Recent progress in nanomaterials for bacteria-related tumor therapy

Many studies suggest that tumor microbiome closely relates to the oncogenesis and anti-tumor responses in multiple cancer types (e.g., colorectal cancer (CRC), breast cancer, lung cancer and pancreatic cancer), thereby raising an emerging research area of bacteria-related tumor therapy. Nanomaterials have long been used for both cancer and bacterial infection treatment, holding great potential for bacteria-related tumor therapy. In this review, we summarized recent progress in nanomaterials for bacteria-related tumor therapy. We focus on the types and mechanisms of pathogenic bacteria in the development and promotion of cancers and emphasize how nanomaterials work. We also briefly discuss the design principles and challenges of nanomaterials for bacteria-related tumor therapy. We hope this review can provide some insights into this emerging and rapidly growing research area.

Early Rectal Cancer and Local Excision: A Narrative Review

A rise in the incidence of early rectal cancer consequent to bowel-screening programs around the world and an increase in the incidence in young adults has led to a growing interest in organ-sparing treatment options. The rectum, being the most distal portion of the large intestine, is a fertile ground for local excision techniques performed with endoscopic or surgical techniques. Moreover, the advancement in endoscopic optical evaluation and the better definition of imaging techniques allow for a more precise local staging of early rectal cancer. Although the local treatment of early rectal cancer seems promising, in clinical practice, a significant number of patients who could benefit from local excision techniques undergo total mesorectal excision (TME) as the first approach. All relevant prospective clinical trials were identified through a computer-assisted search of the PubMed, EMBASE, and Medline databases until January 2024. This review is dedicated to endoscopic and surgical local excision in the treatment of early rectal cancer and highlights its possible role in current and future clinical practice, taking into account surgical completion techniques and chemoradiotherapy.

Downregulation of NAT1 Expression is Associated with Poor Prognosis and Immune Infiltration in COAD

BACKGROUND

An increasing corpus of evidence has identified the involvement of N-acetyltransferase 1 (NAT1), a member of the NAT family, in the progression of various cancers. However, the specific function of NAT1 in colon cancer (COAD) remains elusive. This study aims to decip her the role of NAT1 in COAD and its associated mechanisms.

METHODS

The Tumor Immunity Evaluation Resource (TIMER), The Cancer Genome Atlas (TCGA), and the Gene Expression Omnibus (GEO) databases were employed to assess the NAT1 expression level in COAD. The differential expression between COAD and normal colon tissue was further validated using quantitative real-time reverse-transcription PCR (RT-qPCR) and Western blot (WB) analyses. Additionally, survival analysis of NAT1 in COAD was carried out using the PrognoScan database and TCGA dataset. The functions of NAT1 were explored through gene set enrichment analysis (GSEA) and immuno-infiltration analysis.

RESULTS

There was a significant reduction in NAT1 expression in COAD samples compared to normal tissue. Notably, low NAT1 expression in COAD correlated significantly with various clinical parameters such as tumor stage (T stage, N stage, M stage, pathologic stage), primary therapy outcome, carcinoembryonic antigen (CEA) level, and lymphatic invasion. The downregulation of NAT1 was also strongly linked with poor outcomes in overall survival (OS), progression-free interval (PFI), and disease-specific survival (DSS). Cox regression analysis highlighted NAT1 as an independent prognostic indicator for overall survival in COAD patients. GSEA results revealed NAT1's involvement in multiple pathways, including the neuroactive ligand-receptor interaction, olfactory transduction, olfactory signaling, extracellular matrix receptor interaction, calcium signaling, and focal adhesion pathways. Furthermore, NAT1 expression was found to significantly correlate with infiltration levels of various immune cells.

CONCLUSION

The findings reveal NAT1's potential as a valuable prognostic biomarker for COAD. Moreover, its associated mechanisms offer insights that might pave the way for therapeutic interventions for COAD patients.

Should we perform sigmoidoscopy for colorectal cancer screening in people under 45 years?

BACKGROUND

The strategy for preventing colorectal cancer is screening by colonoscopy, which offers a direct way for detection and removal of adenomatous polyps (APs). American College of Gastroenterology guidelines recommend that people aged ≥ 45 years should undergo colonoscopy; however, how to deal with people aged ≤ 45 years is still unknown.

AIM

To compare the prevalence of APs and high-grade neoplasia between the left and right colon in patients ≤ 45 years.

METHODS

A retrospective observational study was conducted at a single tertiary III hospital in China. This study included patients aged 18-45 years with undergoing initial colonoscopy dissection and pathological diagnosis AP or high-grade neoplasia between February 2014 and January 2021. The number of APs in the entire colon while screening and post-polypectomy surveillance in following 1-3 years were evaluated.

RESULTS

A total of 3053 cases were included. The prevalence of APs in the left and right colon was 55.0% and 41.6%, respectively (OR 1.7, 95%CI 1.6-2.4; P < 0.05). For APs with high-grade neoplasia, the prevalence was 2.7% and 0.9%, respectively (OR 3.0, 95%CI 2.0-4.6; P < 0.05). Therefore, the prevalence of APs and high-grade neoplasia in the left colon was significantly higher than in the right colon in patients aged ≤ 45 years. There were 327 patients who voluntarily participated in post-polypectomy surveillance in following 1-3 years, and APs were found in 216 cases (66.1%); 170 cases had 1-3 polyps (52.0%) and 46 cases had > 3 polyps (14.1%; OR 0.3, 95%CI 0.1-0.6; P < 0.05).

CONCLUSION

This study suggests that flexible sigmoidoscopy would be an optimal approach for initial screening in people aged ≤ 45 years and would be a more cost-effective and safe strategy.

Noninvasive Stratification of Colon Cancer by Multiplex PET Imaging

PURPOSE

The current approach for molecular subtyping of colon cancer relies on gene expression profiling, which is invasive and has limited ability to reveal dynamics and spatial heterogeneity. Molecular imaging techniques, such as PET, present a noninvasive alternative for visualizing biological information from tumors. However, the factors influencing PET imaging phenotype, the suitable PET radiotracers for differentiating tumor subtypes, and the relationship between PET phenotypes and tumor genotype or gene expression-based subtyping remain unknown.

EXPERIMENTAL DESIGN

In this study, we conducted 126 PET scans using four different metabolic PET tracers, [18F]fluorodeoxy-D-glucose ([18F]FDG), O-(2-[18F]fluoroethyl)-l-tyrosine ([18F]FET), 3'-deoxy-3'-[18F]fluorothymidine ([18F]FLT), and [11C]acetate ([11C]ACE), using a spectrum of five preclinical colon cancer models with varying genetics (BMT, AKPN, AK, AKPT, KPN), at three sites (subcutaneous, orthograft, autochthonous) and at two tumor stages (primary vs. metastatic).

RESULTS

The results demonstrate that imaging signatures are influenced by genotype, tumor environment, and stage. PET imaging signatures exhibited significant heterogeneity, with each cancer model displaying distinct radiotracer profiles. Oncogenic Kras and Apc loss showed the most distinctive imaging features, with [18F]FLT and [18F]FET being particularly effective, respectively. The tissue environment notably impacted [18F]FDG uptake, and in a metastatic model, [18F]FET demonstrated higher uptake.

CONCLUSIONS

By examining factors contributing to PET-imaging phenotype, this study establishes the feasibility of noninvasive molecular stratification using multiplex radiotracer PET. It lays the foundation for further exploration of PET-based subtyping in human cancer, thereby facilitating noninvasive molecular diagnosis.

Colorectal cancer screening: A review of current knowledge and progress in research

Colorectal cancer (CRC) is one of the most prevalent malignancies worldwide, being the third most commonly diagnosed malignancy and the second leading cause of cancer-related deaths globally. Despite the progress in screening, early diagnosis, and treatment, approximately 20%-25% of CRC patients still present with metastatic disease at the time of their initial diagnosis. Furthermore, the burden of disease is still expected to increase, especially in individuals younger than 50 years old, among whom early-onset CRC incidence has been increasing. Screening and early detection are pivotal to improve CRC-related outcomes. It is well established that CRC screening not only reduces incidence, but also decreases deaths from CRC. Diverse screening strategies have proven effective in decreasing both CRC incidence and mortality, though variations in efficacy have been reported across the literature. However, uncertainties persist regarding the optimal screening method, age intervals and periodicity. Moreover, adherence to CRC screening remains globally low. In recent years, emerging technologies, notably artificial intelligence, and non-invasive biomarkers, have been developed to overcome these barriers. However, controversy exists over the actual impact of some of the new discoveries on CRC-related outcomes and how to effectively integrate them into daily practice. In this review, we aim to cover the current evidence surrounding CRC screening. We will further critically assess novel approaches under investigation, in an effort to differentiate promising innovations from mere novelties.

Somatic Mutations in Surgically Treated Colorectal Liver Metastases: An Overview

Colorectal cancer is the second most common cause of cancer death in the United States, and up to half of patients develop colorectal liver metastases (CRLMs). Notably, somatic genetic mutations, such as mutations in RAS, BRAF, mismatch repair (MMR) genes, TP53, and SMAD4, have been shown to play a prognostic role in patients with CRLM. This review summarizes and appraises the current literature regarding the most relevant somatic mutations in surgically treated CRLM by not only reviewing representative studies, but also providing recommendations for areas of future research. In addition, advancements in genetic testing and an increasing emphasis on precision medicine have led to a more nuanced understanding of these mutations; thus, more granular data for each mutation are reviewed when available. Importantly, such knowledge can pave the way for precision medicine with the ultimate goal of improving patient outcomes.

The incidence of early onset colorectal cancer in Aotearoa New Zealand: 2000-2020

BACKGROUND

The incidence of early-onset colorectal cancer (EOCRC), diagnosed before age 50, has been rising in many countries in the past few decades. This study aims to evaluate this trend in Aotearoa New Zealand and assess its impact on Māori.

METHODS

Crude incidence and age-standardized incidence of colorectal cancer (CRC) was analyzed from all new cases from the Aotearoa New Zealand national cancer registry for the period 2000-2020. Trends were estimated by sex, ethnicity, age group and location of cancer and projections made to 2040.

RESULTS

Between 2000 and 2020, there were a total of 56,761 cases of CRC diagnosed in Aotearoa New Zealand, 3,702 of these being EOCRC, with age-standardized incidence decreasing significantly (P = 8.2 × 10- 80) from 61.0 to 47.3 cases per 100,000. EOCRC incidence increased on average by 26% per decade (incidence rate ratio (IRR) 1.26, p = < 0.0001) at all sites (proximal colon, distal colon and rectum), while the incidence in those aged 50-79 years decreased on average by 18% per decade (IRR 0.82, p = < 0.0005), again across all sites. There was no significant average change in CRC incidence in those over 80 years. In Māori, there was no significant change in age-standardized incidence. There was however a significant increase in crude incidence rates (IRR 1.28, p = < 0.0005) driven by significant increases in EOCRC (IRR1.36, p = < 0.0005). By 2040, we predict the incidence of EOCRC will have risen from 8.00 to 14.9 per 100,000 (6.33 to 10.00 per 100,000 in Māori). However, due to the aging population an estimated 43.0% of all CRC cases will be diagnosed in those over 80 years of age (45.9% over 70 years of age in Māori).

CONCLUSION

The age-standardized incidence of CRC from 2000 to 2020 decreased in Aotearoa New Zealand, but not for Māori. The incidence of EOCRC over the same period continues to rise, and at a faster rate in Māori. However, with the ageing of the population in Aotearoa New Zealand, and for Māori, CRC in the elderly will continue to dominate case numbers.

Application research of radiomics in colorectal cancer: A bibliometric study

BACKGROUND

Radiomics has shown great potential in the clinical field of colorectal cancer (CRC). However, few bibliometric studies have systematically analyzed existing research in this field. The purpose of this study is to understand the current research status and future development directions of CRC.

METHODS

Search the English documents on the application of radiomics in the field of CRC research included in the Web of Science Core Collection from its establishment to October 2023. VOSviewer and CiteSpace software were used to conduct bibliometric and visual analysis of online publications related to countries/regions, authors, journals, references, and keywords in this field.

RESULTS

A total of 735 relevant documents published from Web of Science Core Collection to October 2023 were retrieved, and a total of 419 documents were obtained based on the screening criteria, including 376 articles and 43 reviews. The number of publications is increasing year by year. Among them, China publishes the most relevant documents (n = 238), which is much higher than Italy (n = 69) and the United States (n = 63). Tian Jie is the author with the most publications and citations (n = 17, citations = 2128), GE Healthcare is the most productive institution (n = 26), Frontiers in Oncology is the journal with the most publications (n = 60), and European Radiology is the most cited journal (n = 776). Hot spots for the application of radiomics in CRC include magnetic resonance, neoadjuvant chemoradiotherapy, survival, texture analysis, and machine learning. These directions are the current hot spots for the application of radiomics research in CRC and may be the direction of continued development in the future.

CONCLUSION

Through bibliometric analysis, the application of radiomics in CRC has been increasing year by year. The application of radiomics improves the accuracy of preoperative diagnosis, prediction, and prognosis of CRC. The results of bibliometrics analysis provide a valuable reference for the research direction of radiomics. However, radiomics still faces many challenges in the future, such as the single nature of the data source which may affect the comprehensiveness of the results. Future studies can further expand the data sources and build a multicenter public database to more comprehensively reflect the research status and development trend of CRC radiomics.

Exploring tumor heterogeneity in colorectal liver metastases by imaging: Unsupervised machine learning of preoperative CT radiomics features for prognostic stratification

OBJECTIVES

This study aimed to investigate tumor heterogeneity of colorectal liver metastases (CRLM) and stratify the patients into different risk groups of prognoses following liver resection by applying an unsupervised radiomics machine-learning approach to preoperative CT images.

METHODS

This retrospective study retrieved clinical information and CT images of 197 patients with CRLM from The Cancer Imaging Archive (TCIA) database. Radiomics features were extracted from a segmented liver lesion identified at the portal venous phase. Those features which showed high stability, non-redundancy, and indicative information were selected. An unsupervised consensus clustering analysis on these features was adopted to identify subgroups of CRLM patients. Overall survival (OS), disease-free survival (DFS), and liver-specific DFS were compared between the identified subgroups. Cox regression analysis was applied to evaluate prognostic risk factors.

RESULTS

A total of 851 radiomics features were extracted, and 56 robust features were finally selected for unsupervised clustering analysis which identified two distinct subgroups (96 and 101 patients respectively). There were significant differences in the OS, DFS, and liver-specific DFS between the subgroups (all log-rank p < 0.05). The subgroup with worse outcome using the proposed radiomics model was consistently associated with shorter OS, DFS, and liver-specific DFS, with hazard ratios of 1.78 (95 %CI: 1.12-2.83), 1.72 (95 %CI: 1.16-2.54), and 1.59 (95 %CI: 1.10-2.31), respectively. The general performance of this radiomics model outperformed the traditional Clinical Risk Score and Tumor Burden Score in the prognosis prediction after surgery for CRLM.

CONCLUSION

Radiomics features derived from preoperative CT images can reveal the heterogeneity of CRLM and stratify the patients with CRLM into subgroups with significantly different clinical outcomes.

Fluorouracil, Leucovorin, and Irinotecan Plus Cetuximab Versus Cetuximab as Maintenance Therapy in First-Line Therapy for RAS and BRAF Wild-Type Metastatic Colorectal Cancer: Phase III ERMES Study

PURPOSE

The intensity of anti-EGFR-based first-line therapy for RAS/BRAF wild-type (wt) metastatic colorectal cancer (mCRC), once disease control is achieved, is controversial. A de-escalation strategy with anti-EGFR monotherapy represents a potential option to maintain efficacy while reducing cytotoxicity.

METHODS

In this multicenter, open-label, phase III trial, patients with untreated RAS/BRAF wt mCRC were randomly assigned to receive either fluorouracil, leucovorin, and irinotecan/cetuximab (FOLFIRI/Cet) until disease progression (arm A) or FOLFIRI/Cet for eight cycles followed by Cet alone (arm B). The coprimary end points were a noninferior progression-free survival (PFS) in the modified per-protocol (mPP) population (>eight cycles) and a lower incidence of grade (G) 3-4 adverse events (AEs) for arm B compared with arm A.

RESULTS

Overall, 606 patients were randomly assigned, with 300 assigned to arm A and 306 to arm B. The median follow-up was 22.3 months. In the mPP population, 291 events occurred with a PFS of 10 versus 12.2 months for arms B and A, respectively (P of noninferiority = .43). In the intention-to-treatment (ITT, ≥one cycle) population, 503 events occurred with a PFS of 9 versus 10.7 months (P = .39). The overall survival was 35.7 versus 30.7 months (P = .119) and 31.0 versus 25.2 months (P = .32) in the mPP and ITT population, respectively. Arm B had lower G3-4 AEs during the maintenance period than arm A (20.2% v 35.1%).

CONCLUSION

The ERMES study did not demonstrate noninferiority of maintenance with Cet alone. Despite a more favorable safety profile, maintenance with single-agent Cet after induction with FOLFIRI/Cet cannot be recommended for all patients but could represent an option in selected cases.

Molecular insights into clinical trials for immune checkpoint inhibitors in colorectal cancer: Unravelling challenges and future directions

Colorectal cancer (CRC) is a complex disease with diverse etiologies and clinical outcomes. Despite considerable progress in development of CRC therapeutics, challenges remain regarding the diagnosis and management of advanced stage metastatic CRC (mCRC). In particular, the five-year survival rate is very low since mCRC is currently rarely curable. Over the past decade, cancer treatment has significantly improved with the introduction of cancer immunotherapies, specifically immune checkpoint inhibitors. Therapies aimed at blocking immune checkpoints such as PD-1, PD-L1, and CTLA-4 target inhibitory pathways of the immune system, and thereby enhance anti-tumor immunity. These therapies thus have shown promising results in many clinical trials alone or in combination. The efficacy and safety of immunotherapy, either alone or in combination with CRC, have been investigated in several clinical trials. Clinical trials, including KEYNOTE-164 and CheckMate 142, have led to Food and Drug Administration approval of the PD-1 inhibitors pembrolizumab and nivolumab, respectively, for the treatment of patients with unresectable or metastatic microsatellite instability-high or deficient mismatch repair CRC. Unfortunately, these drugs benefit only a small percentage of patients, with the benefits of immunotherapy remaining elusive for the vast majority of CRC patients. To this end, primary and secondary resistance to immunotherapy remains a significant issue, and further research is necessary to optimize the use of immunotherapy in CRC and identify biomarkers to predict the response. This review provides a comprehensive overview of the clinical trials involving immune checkpoint inhibitors in CRC. The underlying rationale, challenges faced, and potential future steps to improve the prognosis and enhance the likelihood of successful trials in this field are discussed.

Recent clinical trials and optical control as a potential strategy to develop microtubule-targeting drugs in colorectal cancer management

Colorectal cancer (CRC) has remained the second and the third leading cause of cancer-related death worldwide and in the United States, respectively. Although significant improvement in overall survival has been achieved, death in adult populations under the age of 55 appears to have increased in the past decades. Although new classes of therapeutic strategies such as immunotherapy have emerged, their application is very limited in CRC so far. Microtubule (MT) inhibitors such as taxanes, are not generally successful in CRC. There may be some way to make MT inhibitors work effectively in CRC. One potential advantage that we can take to treat CRC may be the combination of optical techniques coupled to an endoscope or other fiber optics-based devices. A combination of optical devices and photo-activatable drugs may allow us to locally target advanced CRC cells with highly potent MT-targeting drugs. In this Editorial review, we would like to discuss the potential of optogenetic approaches in CRC management.

Imaging Considerations before and after Liver-Directed Locoregional Treatments for Metastatic Colorectal Cancer

Colorectal cancer is a leading cause of cancer-related death. Liver metastases will develop in over one-third of patients with colorectal cancer and are a major cause of morbidity and mortality. Even though surgical resection has been considered the mainstay of treatment, only approximately 20% of the patients are surgical candidates. Liver-directed locoregional therapies such as thermal ablation, Yttrium-90 transarterial radioembolization, and stereotactic body radiation therapy are pivotal in managing colorectal liver metastatic disease. Comprehensive pre- and post-intervention imaging, encompassing both anatomic and metabolic assessments, is invaluable for precise treatment planning, staging, treatment response assessment, and the prompt identification of local or distant tumor progression. This review outlines the value of imaging for colorectal liver metastatic disease and offers insights into imaging follow-up after locoregional liver-directed therapy.

Unraveling the complexities of early-onset colorectal cancer: a perspective on dietary and microbial influences

While advances in screening have resulted in declining rates of colorectal cancer (CRC) among adults ≥50 years of age since the mid-2000s, the incidence of early-onset CRC (EOCRC) has steadily increased over the last decade. This increase is not fully accounted for by hereditary factors, and the hypothesis that a sedentary lifestyle and obesity are the primary culprits is not fully supported by recent reports indicating that many affected individuals lead active lifestyles, maintain normal weight, and are otherwise healthy. Attention has shifted toward dietary patterns, notably the consumption of processed and ultra-processed foods found in Western diets, which are suspected of disrupting the gut microbiome balance that potentially leads to EOCRC. The impact of antibiotic use on the gut microbiome is also posited as a contributing factor, given its rising prevalence in medical and agricultural practices. We propose that a paradigm shift is necessary for EOCRC research, moving beyond metabolic factors to a broader exploration of dietary and microbial influences. Future research must prioritize understanding the relationship between dietary habits, particularly processed food intake, antibiotic exposure, and gut microbiome dynamics, to unravel the complex etiology of EOCRC. This will be crucial in developing comprehensive preventive strategies to address the increasing incidence of this malignancy in younger populations.

Molecular subtyping and the construction of a predictive model of colorectal cancer based on ion channel genes

PURPOSE

Colorectal cancer (CRC) is a highly heterogeneous malignancy with an unfavorable prognosis. The purpose of this study was to address the heterogeneity of CRC by categorizing it into ion channel subtypes, and to develop a predictive modeling based on ion channel genes to predict the survival and immunological states of patients with CRC. The model will provide guidance for personalized immunotherapy and drug treatment.

METHODS

A consistent clustering method was used to classify 619 CRC samples based on the expression of 279 ion channel genes. Such a method was allowed to investigate the relationship between molecular subtypes, prognosis, and immune infiltration. Furthermore, a predictive modeling was constructed for ion channels to evaluate the ion channel properties of individual tumors using the least absolute shrinkage and selection operator. The expression patterns of the characteristic genes were validated through molecular biology experiments. The effect of potassium channel tetramerization domain containing 9 (KCTD9) on CRC was verified by cellular functional experiments.

RESULTS

Four distinct ion channel subtypes were identified in CRC, each characterized by unique prognosis and immune infiltration patterns. Notably, Ion Cluster3 exhibited high levels of immune infiltration and a favorable prognosis, while Ion Cluster4 showed relatively lower levels of immune infiltration and a poorer prognosis. The ion channel score could predict overall survival, with lower scores correlated with longer survival. This score served as an independent prognostic factor and presented an excellent predictive efficacy in the nomogram. In addition, the score was closely related to immune infiltration, immunotherapy response, and chemotherapy sensitivity. Experimental evidence further confirmed that low expression of KCTD9 in tumor tissues was associated with an unfavorable prognosis in patients with CRC. The cellular functional experiments demonstrated that KCTD9 inhibited the proliferation, migration and invasion capabilities of LOVO cells.

CONCLUSIONS

Ion channel subtyping and scoring can effectively predict the prognosis and evaluate the immune microenvironment, immunotherapy response, and drug sensitivity in patients with CRC.

Tumor regression and safe distance of distal margin after neoadjuvant therapy for rectal cancer

Neoadjuvant therapy has been widely employed in the treatment of rectal cancer, demonstrating its utility in reducing tumor volume, downstaging tumors, and improving patient prognosis. It has become the standard preoperative treatment modality for locally advanced rectal cancer. However, the efficacy of neoadjuvant therapy varies significantly among patients, with notable differences in tumor regression outcomes. In some cases, patients exhibit substantial tumor regression, even achieving pathological complete response. The assessment of tumor regression outcomes holds crucial significance for determining surgical approaches and establishing safe margins. Nonetheless, current research on tumor regression patterns remains limited, and there is considerable controversy surrounding the determination of a safe margin after neoadjuvant therapy. In light of these factors, this study aims to summarize the primary patterns of tumor regression observed following neoadjuvant therapy for rectal cancer, categorizing them into three types: tumor shrinkage, tumor fragmentation, and mucinous lake formation. Furthermore, a comparison will be made between gross and microscopic tumor regression, highlighting the asynchronous nature of regression in the two contexts. Additionally, this study will analyze the safety of non-surgical treatment in patients who achieve complete clinical response, elucidating the necessity of surgical intervention. Lastly, the study will investigate the optimal range for safe surgical resection margins and explore the concept of a safe margin distance post-neoadjuvant therapy.

Lectin-Based Immunophenotyping and Whole Proteomic Profiling of CT-26 Colon Carcinoma Murine Model

A murine colorectal carcinoma (CRC) model was established. CT26 colon carcinoma cells were injected into BALB/c mice's spleen to study the primary tumor and the mechanisms of cell spread of colon cancer to the liver. The CRC was verified by the immunohistochemistry of Pan Cytokeratin and Vimentin expression. Immunophenotyping of leukocytes isolated from CRC-bearing BALB/c mice or healthy controls, such as CD19+ B cells, CD11+ myeloid cells, and CD3+ T cells, was carried out using fluorochrome-labeled lectins. The binding of six lectins to white blood cells, such as galectin-1 (Gal1), siglec-1 (Sig1), Sambucus nigra lectin (SNA), Aleuria aurantia lectin (AAL), Phytolacca americana lectin (PWM), and galectin-3 (Gal3), was assayed. Flow cytometric analysis of the splenocytes revealed the increased binding of SNA, and AAL to CD3 + T cells and CD11b myeloid cells; and increased siglec-1 and AAL binding to CD19 B cells of the tumor-bearing mice. The whole proteomic analysis of the established CRC-bearing liver and spleen versus healthy tissues identified differentially expressed proteins, characteristic of the primary or secondary CRC tissues. KEGG Gene Ontology bioinformatic analysis delineated the established murine CRC characteristic protein interaction networks, biological pathways, and cellular processes involved in CRC. Galectin-1 and S100A4 were identified as upregulated proteins in the primary and secondary CT26 tumor tissues, and these were previously reported to contribute to the poor prognosis of CRC patients. Modelling the development of liver colonization of CRC by the injection of CT26 cells into the spleen may facilitate the understanding of carcinogenesis in human CRC and contribute to the development of novel therapeutic strategies.

Investigation of long non-coding RNAs in extracellular vesicles from low-volume blood serum specimens of colorectal cancer patients

Colorectal cancer (CRC) is the second most prevalent cancer type worldwide, which highlights the urgent need for non-invasive biomarkers for its early detection and improved prognosis. We aimed to investigate the patterns of long non-coding RNAs (lncRNAs) in small extracellular vesicles (sEVs) collected from low-volume blood serum specimens of CRC patients, focusing on their potential as diagnostic biomarkers. Our research comprised two phases: an initial exploratory phase involving RNA sequencing of sEVs from 76 CRC patients and 29 healthy controls, and a subsequent validation phase with a larger cohort of 159 CRC patients and 138 healthy controls. Techniques such as dynamic light scattering, transmission electron microscopy, and Western blotting were utilized for sEV characterization. Optimized protocol for sEV purification, RNA isolation and preamplification was applied to successfully sequence the RNA content of sEVs and validate the results by RT-qPCR. We successfully isolated sEVs from blood serum and prepared sequencing libraries from a low amount of RNA. High-throughput sequencing identified differential levels of 460 transcripts between CRC patients and healthy controls, including mRNAs, lncRNAs, and pseudogenes, with approximately 20% being lncRNAs, highlighting several tumor-specific lncRNAs that have not been associated with CRC development and progression. The validation phase confirmed the upregulation of three lncRNAs (NALT1, AL096828, and LINC01637) in blood serum of CRC patients. This study not only identified lncRNA profiles in a population of sEVs from low-volume blood serum specimens of CRC patients but also highlights the value of innovative techniques in biomolecular research, particularly for the detection and analysis of low-abundance biomolecules in clinical samples. The identification of specific lncRNAs associated with CRC provides a foundation for future research into their functional roles in cancer development and potential clinical applications.

Early screening of colorectal cancer using feature engineering with artificial intelligence-enhanced analysis of nanoscale chromatin modifications

Colonoscopy is accurate but inefficient for colorectal cancer (CRC) prevention due to the low (~ 7 to 8%) prevalence of target lesions, advanced adenomas. We leveraged rectal mucosa to identify patients who harbor CRC field carcinogenesis by evaluating chromatin 3D architecture. Supranucleosomal disordered chromatin chains (~ 5 to 20 nm, ~1 kbp) fold into chromatin packing domains (~ 100 to 200 nm, ~ 100 to 1000 kbp). In turn, the fractal-like conformation of DNA within chromatin domains and the folding of the genome into packing domains has been shown to influence multiple facets of gene transcription, including the transcriptional plasticity of cancer cells. We deployed an optical spectroscopic nanosensing technique, chromatin-sensitive partial wave spectroscopic microscopy (csPWS), to evaluate the packing density scaling D of the chromatin chain conformation within packing domains from rectal mucosa in 256 patients with varying degrees of progression to colorectal cancer. We found average packing scaling D of chromatin domains was elevated in tumor cells, histologically normal-appearing cells 4 cm proximal to the tumor, and histologically normal-appearing rectal mucosa compared to cells from control patients (p < 0.001). Nuclear D had a robust correlation with the model of 5-year risk of CRC with r2 = 0.94. Furthermore, rectal D was evaluated as a screening biomarker for patients with advanced adenomas presenting an AUC of 0.85 and 85% sensitivity and specificity. artificial intelligence-enhanced csPWS improved diagnostic performance with AUC = 0.90. Considering the low sensitivity of existing CRC tests, including liquid biopsies, to early-stage cancers our work highlights the potential of chromatin biomarkers of field carcinogenesis in detecting early, significant precancerous colon lesions.

Bifidobacterium modulation of tumor immunotherapy and its mechanism

The advent of tumor immunotherapy in patients has revolutionized the treatment of tumors and significantly improved survival rates for a wide range of tumors. However, the full therapeutic potential of immune checkpoint inhibitors (ICIs) has yet to be realized, as not all patients have a lasting survival benefit from them, and a significant proportion of patients show primary or acquired resistance to immunotherapy. Bifidobacterium is one of the most common probiotics, and its antitumor and immunomodulatory effects have been demonstrated in recent years, but its immunomodulatory effects in tumors, especially on ICIs and in combination, have not been extensively studied in clinical practice, and its effects on the immune system and the mechanisms that modulate immunotherapy are largely unknown. Therefore, this review will focus on the immunomodulatory effects of Bifidobacteria in malignancies and the possible mechanisms of action of Bifidobacteria on immunotherapy in the hope of providing a basis for further research and better application of Bifidobacteria in clinical practice.

Polyp Segmentation Using a Hybrid Vision Transformer and a Hybrid Loss Function

Accurate and early detection of precursor adenomatous polyps and their removal at the early stage can significantly decrease the mortality rate and the occurrence of the disease since most colorectal cancer evolve from adenomatous polyps. However, accurate detection and segmentation of the polyps by doctors are difficult mainly these factors: (i) quality of the screening of the polyps with colonoscopy depends on the imaging quality and the experience of the doctors; (ii) visual inspection by doctors is time-consuming, burdensome, and tiring; (iii) prolonged visual inspections can lead to polyps being missed even when the physician is experienced. To overcome these problems, computer-aided methods have been proposed. However, they have some disadvantages or limitations. Therefore, in this work, a new architecture based on residual transformer layers has been designed and used for polyp segmentation. In the proposed segmentation, both high-level semantic features and low-level spatial features have been utilized. Also, a novel hybrid loss function has been proposed. The loss function designed with focal Tversky loss, binary cross-entropy, and Jaccard index reduces image-wise and pixel-wise differences as well as improves regional consistencies. Experimental works have indicated the effectiveness of the proposed approach in terms of dice similarity (0.9048), recall (0.9041), precision (0.9057), and F2 score (0.8993). Comparisons with the state-of-the-art methods have shown its better performance.

Comparing ancestry calibration approaches for a trans-ancestry colorectal cancer polygenic risk score

Background

Colorectal cancer (CRC) is a complex disease with monogenic, polygenic and environmental risk factors. Polygenic risk scores (PRS) are being developed to identify high polygenic risk individuals. Due to differences in genetic background, PRS distributions vary by ancestry, necessitating calibration.

Methods

We compared four calibration methods using the All of Us Research Program Whole Genome Sequence data for a CRC PRS previously developed in participants of European and East Asian ancestry. The methods contrasted results from linear models with A) the entire data set or an ancestrally diverse training set AND B) covariates including principal components of ancestry or admixture. Calibration with the training set adjusted the variance in addition to the mean.

Results

All methods performed similarly within ancestry with OR (95% C.I.) per s.d. change in PRS: African 1.5 (1.02, 2.08), Admixed American 2.2 (1.27, 3.85), European 1.6 (1.43, 1.89), and Middle Eastern 1.1 (0.71, 1.63). Using admixture and an ancestrally diverse training set provided distributions closest to standard Normal with accurate upper tail frequencies.

Conclusion

Although the PRS is predictive of CRC risk for most ancestries, its performance varies by ancestry. Post-hoc calibration preserves the risk prediction within ancestries. Training a calibration model on ancestrally diverse participants to adjust both the mean and variance of the PRS, using admixture as covariates, created standard Normal z-scores. These z-scores can be used to identify patients at high polygenic risk, and can be incorporated into comprehensive risk scores including other known risk factors, allowing for more precise risk estimates.

Image-based artificial intelligence for the prediction of pathological complete response to neoadjuvant chemoradiotherapy in patients with rectal cancer: a systematic review and meta-analysis

OBJECTIVE

Artificial intelligence (AI) holds enormous potential for noninvasively identifying patients with rectal cancer who could achieve pathological complete response (pCR) following neoadjuvant chemoradiotherapy (nCRT). We aimed to conduct a meta-analysis to summarize the diagnostic performance of image-based AI models for predicting pCR to nCRT in patients with rectal cancer.

METHODS

This study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A literature search of PubMed, Embase, Cochrane Library, and Web of Science was performed from inception to July 29, 2023. Studies that developed or utilized AI models for predicting pCR to nCRT in rectal cancer from medical images were included. The Quality Assessment of Diagnostic Accuracy Studies-AI was used to appraise the methodological quality of the studies. The bivariate random-effects model was used to summarize the individual sensitivities, specificities, and areas-under-the-curve (AUCs). Subgroup and meta-regression analyses were conducted to identify potential sources of heterogeneity. Protocol for this study was registered with PROSPERO (CRD42022382374).

RESULTS

Thirty-four studies (9933 patients) were identified. Pooled estimates of sensitivity, specificity, and AUC of AI models for pCR prediction were 82% (95% CI: 76-87%), 84% (95% CI: 79-88%), and 90% (95% CI: 87-92%), respectively. Higher specificity was seen for the Asian population, low risk of bias, and deep-learning, compared with the non-Asian population, high risk of bias, and radiomics (all P < 0.05). Single-center had a higher sensitivity than multi-center (P = 0.001). The retrospective design had lower sensitivity (P = 0.012) but higher specificity (P < 0.001) than the prospective design. MRI showed higher sensitivity (P = 0.001) but lower specificity (P = 0.044) than non-MRI. The sensitivity and specificity of internal validation were higher than those of external validation (both P = 0.005).

CONCLUSIONS

Image-based AI models exhibited favorable performance for predicting pCR to nCRT in rectal cancer. However, further clinical trials are warranted to verify the findings.

PHGDH knockdown increases sensitivity to SR1, an aryl hydrocarbon receptor antagonist, in colorectal cancer by activating the autophagy pathway

Colorectal cancer (CRC) has emerged as the third most prevalent and second deadliest cancer worldwide. Metabolic reprogramming is a key hallmark of cancer cells. Phosphoglycerate dehydrogenase (PHGDH) is over-expressed in multiple cancers, including CRC. Although the role of PHGDH in metabolism has been extensively investigated, its effects on CRC development remains to be elucidated. In the present study, it was demonstrated that PHGDH expression was significantly up-regulated in colorectal cancer. PHGDH expression was positively correlated with that of the aryl hydrocarbon receptor (AhR) and its target genes, CYP1A1 and CYP1B1, in CRC cells. Knockdown of PHGDH reduced AhR levels and activity, as well as the ratio of reduced to oxidized glutathione. The selective AhR antagonist stemregenin 1 induced cell death through reactive oxygen species-dependent autophagy in CRC cells. PHGDH knockdown induced CRC cell sensitivity to stemregenin 1 via the autophagy pathway. Our findings suggest that PHGDH modulates AhR signaling and the redox-dependent autophagy pathway in CRC, and that the combination of inhibition of both PHGDH and AhR may be a novel therapeutic strategy for CRC.

Synergic actions of botulinum neurotoxin A and oxaliplatin on colorectal tumour cell death through the upregulation of TRPM2 channel-mediated oxidative stress

Botulinum neurotoxin A (BoNT) is being shown to have anticancer action as a potential adjuvant treatment. The transient receptor potential (TRP) melastatin 2 (TRPM2) stimulator action of BoNT was reported in glioblastoma cells, but not in colorectal cancer (HT29) cells. By activating TRPM2, we evaluated the impacts of BoNT and oxaliplatin (OXA) incubations on oxidant and apoptotic values within the HT29 cells. Control, BoNT (5 IU for 24 h), OXA (50 μM for 24 h) and their combinations were induced. We found that TRPM2 protein is upregulated and mediates enhanced BoNT and OXA-induced Ca2+ entry in cells as compared to control cells. The increase of free reactive oxygen species (ROS), but the decrease of glutathione is the main ROS responsible for TRPM2 activation on H29 exposure to oxidative stress. BoNT and OXA-mediated Ca2+ entry through TRPM2 stimulation in response to H2 O2 results in mitochondrial Ca2+ overload, followed by mitochondrial membrane depolarization, apoptosis and caspase-3/-8/-9, although they were diminished in the TRPM2 antagonist groups (N-(p-amylcinnamoyl)anthranilic acid and carvacrol). In conclusion, by increasing the susceptibility of HT29 tumour cells to oxidative stress and apoptosis, the combined administration of BoNT and OXA via the targeting of TRPM2 may offer a different approach to kill the tumour cells.

Correlates of U.S. Adults Aged 50-75 Years Having Had a Colorectal Cancer Screening Test

Introduction

Colorectal cancer is a leading cause of cancer death in the U.S. Until 2021, the U.S. Preventive Services Task Force recommended colorectal cancer screening for all adults aged 50-75 years. Using a nationally representative sample, we explored the associations between having colorectal cancer screening and key sociodemographic and health-related factors among U.S. adults aged 50-75 years.

Methods

We analyzed self-reported data from the National Cancer Institute's Health Information National Trends Survey 5 (Cycle 4) collected from February to June 2020. A multivariable weighted logistic regression model was conducted using all of the factors that were univariably significant with p<0.10. Using backward elimination, factors that were not significant with p>0.05 were removed one at a time until the remaining factors were all significant collectively with p<0.05.

Results

Complete data were available for 1,649 respondents: 1,384 (81.2% weighted) had a colorectal cancer screening test, and 265 (18.8% weighted) did not. Multivariably, the odds of having had a colorectal cancer screening test increased with age (OR=1.07) and were higher for participants who identified as Black/African American than for White participants (OR=2.4), participants who had a family member who ever had cancer (OR=1.7), participants who believed that being overweight and obese influences development of cancer a lot than those who believed not at all (OR=2.0), and participants who had friends or family to talk with about health (OR=2.3).

Conclusions

Age, race, family history, weight-related beliefs about the causes of cancer, and having someone to talk with about health were associated with having colorectal cancer screening test.

Evolving survival gains in patients with young-onset colorectal cancer and synchronous resectable liver metastases

We aimed to evaluate the practice and the associated outcomes of surgical treatment for young-onset colorectal cancer (YOCRC) patients presenting with synchronous liver metastases. The study cohort was divided into two groups according to surgery date: 131 patients in the early era (EE, 1998-2011) and 179 in the contemporary era (CE, 2012-2020). The CE had a higher rate of node-positive primary tumors, higher carcinoembryonic antigen level, and lower rate of RAS/BRAF mutations. The CE had higher rates of reverse or combined resection, multi-drug prehepatectomy chemotherapy, and two-stage hepatectomy. The median survival was 8.4 years in the CE and 4.3 years in the EE (p = 0.011). On multivariate analysis, hepatectomy in the CE was independently associated with improved overall survival (HR 0.48, p = 0.001). With a combination of perioperative systemic therapy, careful selection of treatment approach, and coordinated resections, durable cure can be achieved in YOCRC patients.

"Nutrient-fungi-host" tripartite interaction in cancer progression

The human microbiome exhibits a profound connection with the cancer development, progression, and therapeutic response, with particular emphasis on its components of the mycobiome, which are still in the early stages of research. In this review, we comprehensively summarize cancer-related symbiotic and pathogenic fungal genera. The intricate mechanisms through which fungi impact cancer as an integral member of both gut and tissue-resident microbiomes are further discussed. In addition, we shed light on the pivotal physiological roles of various nutrients, including cholesterol, carbohydrates, proteins and minerals, in facilitating the growth, reproduction, and invasive pathogenesis of the fungi. While our exploration of the interplay between nutrients and cancer, mediated by the mycobiome, is ongoing, the current findings have yet to yield conclusive results. Thus, delving into the relationship between nutrients and fungal pathogenesis in cancer development and progression would provide valuable insights into anticancer therapy and foster precision nutrition and individualized treatments that target fungi from bench to bedside.

Peptide mimetic NC114 induces growth arrest by preventing PKCδ activation and FOXM1 nuclear translocation in colorectal cancer cells

The peptide mimetic, NC114, is a promising anticancer compound that specifically kills colorectal cancer cells without affecting normal colon epithelial cells. In our previous study, we observed that NC114 inhibited the Wnt/β-catenin pathway, with significant downregulation of both Ser 675-phosphorylated β-catenin and its target genes, cyclin D1 and survivin. However, the molecular mechanism responsible for its cytotoxic effect has not yet been fully characterized. In the present study, we demonstrated that NC114 prevented cell cycle progression from S to G2/M phase by downregulating cell cycle-related gene expression, and also induced growth arrest in SW480 and HCT-116 colorectal cancer cells. A novel covariation network analysis combined with transcriptome analysis revealed a series of signaling cascades affected by NC114 treatment, and identified protein kinase C-δ (PKCδ) and forkhead box protein M1 (FOXM1) as important regulatory factors for NC114-induced growth arrest. NC114 treatment inhibits the activation of PKCδ and its kinase activity, which suppresses MEK/ERK signaling. Attenuated MEK/ERK signaling then results in a reduction in FOXM1 phosphorylation and subsequent nuclear translocation of FOXM1 and β-catenin. Consequently, formation of a T-cell factor-4 (TCF4)/β-catenin transcription complex in the nucleus is inhibited and transcription of its target genes, such as cell cycle-related genes, is downregulated. The efficacy of NC114 on tumor growth was confirmed in a xenograft model. Collectively, elucidation of the mechanism by which NC114 induces growth arrest in colorectal cancer cells should provide a novel therapeutic strategy for colorectal cancer treatment.

Harnessing the Potential of Real-World Evidence in the Treatment of Colorectal Cancer: Where Do We Stand?

OPINION STATEMENT

Treatment guidelines for colorectal cancer (CRC) are primarily based on the results of randomized clinical trials (RCTs), the gold standard methodology to evaluate safety and efficacy of oncological treatments. However, generalizability of trial results is often limited due to stringent eligibility criteria, underrepresentation of specific populations, and more heterogeneity in clinical practice. This may result in an efficacy-effectiveness gap and uncertainty regarding meaningful benefit versus treatment harm. Meanwhile, conduct of traditional RCTs has become increasingly challenging due to identification of a growing number of (small) molecular subtypes. These challenges-combined with the digitalization of health records-have led to growing interest in use of real-world data (RWD) to complement evidence from RCTs. RWD is used to evaluate epidemiological trends, quality of care, treatment effectiveness, long-term (rare) safety, and quality of life (QoL) measures. In addition, RWD is increasingly considered in decision-making by clinicians, regulators, and payers. In this narrative review, we elaborate on these applications in CRC, and provide illustrative examples. As long as the quality of RWD is safeguarded, ongoing developments, such as common data models, federated learning, and predictive modelling, will further unfold its potential. First, whenever possible, we recommend conducting pragmatic trials, such as registry-based RCTs, to optimize generalizability and answer clinical questions that are not addressed in registrational trials. Second, we argue that marketing approval should be conditional for patients who would have been ineligible for the registrational trial, awaiting planned (non) randomized evaluation of outcomes in the real world. Third, high-quality effectiveness results should be incorporated in treatment guidelines to aid in patient counseling. We believe that a coordinated effort from all stakeholders is essential to improve the quality of RWD, create a learning healthcare system with optimal use of trials and real-world evidence (RWE), and ultimately ensure personalized care for every CRC patient.

Metastasectomy and Stereotactic Body Radiotherapy for Colorectal Cancer With Liver and Lung Oligometastases: A Case Report of Complete Remission in a 96-Year-Old Patient

We report a rare case of an extremely old colorectal cancer (CRC) patient who had complete remission after liver metastasectomy and stereotactic body radiotherapy (SBRT) to lung oligometastases (OM), with good quality of life and no evidence of recurrence 12 years after the initial diagnosis. An 83-year-old male patient had a right hemicolectomy for stage pT3 pN0 adenocarcinoma of the colon. Soon he was found to have liver metastasis treated with radiofrequency ablation and then liver metastasectomy with clear margins, followed by chemotherapy in the form of FOLFIRI for six months. Six years later, positron emission tomography (PET) showed 1.6 cm OM in the left upper lobe lung. He was not considered a good candidate for surgery. We offered him SBRT 48 Gy in four fractions every other day. The lesion disappeared with no recurrence in the same location on PET and serial computed tomography (CT) scans. Three years later, PET-CT found a new OM in the left lingular lung measuring 1.2 cm. A CT-guided lung biopsy confirmed invasive adenocarcinoma favoring OM from the CRC. SBRT planning failed due to its proximity to the heart. He accepted the longer course of conventional volumetric modulated arc therapy at 60 Gy in 15 fractions with daily cone-beam CT guidance. Again, he tolerated treatment very well with no significant side effects, despite his age. He did not require any chemotherapy or other systemic treatment in the last 11 years, so he did not experience any toxicities related to such treatment. This case is important to show that old age alone should not be considered a contraindication for metastasectomy and SBRT for CRC with liver and lung OM.

Cannabidiol activates MAPK pathway to induce apoptosis, paraptosis, and autophagy in colorectal cancer cells

Mitogen-activated protein kinase (MAPK) activation by natural compounds is known to be involved in the induction of apoptosis, paraptosis, and autophagy. Cannabidiol (CBD), a bioactive compound found in Cannabis sativa, is endowed with many pharmacological activities. We investigated the cytotoxic effect of CBD in a panel of colorectal cancer (CRC) cells (HT-29, SW480, HCT-116, and HCT-15). CBD induced significant cytotoxicity as evidenced by the results of MTT  assay, live-dead assay, and flow cytometric analysis. Since CBD displayed cytotoxicity against CRC cells, we examined the effect of CBD on apoptosis, paraptosis, and autophagy. CBD decreased the expression of antiapoptotic proteins and increased the Annexin-V-positive as well as TUNEL-positive cells suggesting that CBD induces apoptosis. CBD increased the expression of ATF4 (activating transcription factor 4) and CHOP (CCAAT/enhancer-binding protein homologous protein), elevated endoplasmic reticulum stress, and enhanced reactive oxygen species levels indicating that CBD also promotes paraptosis. CBD also induced the expression of Atg7, phospho-Beclin-1, and LC3 suggesting that CBD also accelerates autophagy. Since, the MAPK pathway is a common cascade that is involved in the regulation of apoptosis, paraptosis, and autophagy, we investigated the effect of CBD on the activation of JNK, p38, and ERK pathways. CBD activated all the forms of MAPK proteins and pharmacological inhibition of these proteins reverted the observed effects. Our findings implied that CBD could induce CRC cell death by activating apoptosis, paraptosis, and autophagy through the activation of the MAPK pathway.

A novel log odds of positive lymph nodes-based nomogram for predicting overall survival in patients with colorectal signet ring cell carcinoma: a SEER population-based study

PURPOSE

Considering the poor prognosis and high lymph node (LN) involvement rate of colorectal signet ring cell carcinoma (SRCC), this study aimed to construct a prognostic nomogram to predict overall survival (OS) with satisfactory accuracy and utility, based on LN status indicators with superior predictability.

METHODS

Using the Surveillance, Epidemiology, and End Results (SEER) database, we obtained cases of colorectal SRCC patients and employed univariate and multivariate Cox analyses to determine independent prognostic factors. Kaplan-Meier curves were utilized to visualize survival differences among these factors. Receiver operating characteristic curves were generated to assess predictive performances of models incorporating various LN status indicators. A novel nomogram, containing optimal LN status indicators and other prognostic factors, was developed to predict OS, whose discriminatory ability and accuracy were evaluated using calibration curves and decision curve analysis.

RESULTS

A total of 1663 SRCC patients were screened from SEER database. Older patients and those with grades III-IV, tumor sizes > 39 mm, T3/T4 stage, N1/N2 stage, M1 stage, and higher log odds of positive lymph nodes (LODDS) values exhibited poorer prognoses. Age, grade, tumor size, TNM stage, and LODDS were independent prognostic factors. The model containing N stage and LODDS outperformed the one relying solely on N stage as LN status indicator, resulting in a validated nomogram for accurately predicting OS in SRCC patients.

CONCLUSION

The integration of LODDS, N stage, and other risk factors into a nomogram offered precise OS predictions, enhancing therapeutic decision-making and tailored follow-up management for colorectal SRCC patients.

Trends in mortality from gastrointestinal, hepatic, and pancreatic cancers in the United States: A comprehensive analysis (1999-2020)

Background and Aim

This study investigates temporal trends in gastrointestinal cancer-related mortality in the United States between 1999 and 2020, focusing on differences by sex, age, and race.

Methods

We investigated the Centers for Disease Control and Prevention Wide-Ranging Online Data for Epidemiologic Research multiple causes of death database (Years 1999-2020) for gastrointestinal cancer-related mortality with a focus on the underlying cause of death.

Results

A total of 3 115 243 gastrointestinal cancer-related deaths occurred from 1999 to 2020. The overall age-adjusted mortality rate decreased from 46.7 per 100 000 in 1999 to 38.4 per 100 000 in 2020. The average annual percent change (AAPC) for the study period was -0.9% (95% CI: -1.0%, -0.9%, P < 0.001), with no significant difference in AAPC between the sexes but some difference between races and related to individual cancers. African Americans and Asian Americans, and Pacific Islanders experienced a greater decrease in mortality compared with Whites. Mortality rates for American Indian and Alaskan Native populations also decreased significantly from 1999 to 2020 (P < 0.001). There were significant declines in esophageal, stomach, colon, rectal, and gallbladder cancer-related mortality but increases in the small bowel, anal, pancreatic, and hepatic cancer-related mortality (P < 0.001), with variation across different sexes and racial groups.

Conclusion

While overall gastrointestinal cancer-related mortality declined significantly in the United States from 1999 to 2020, mortality from some cancers increased. Furthermore, differences between sexes and racial groups underscore crucial differences in gastrointestinal cancer mortality, highlighting areas for future research.

Post-operative C-reactive protein as a strong independent predictor of long-term colorectal cancer outcomes: consistent findings from two large patient cohorts

BACKGROUND

Post-surgery blood-based biomarkers may be useful for guiding treatment and surveillance decisions among colorectal cancer (CRC) patients. However, most candidate biomarkers provide little if any predictive value beyond stage at diagnosis. We aimed to investigate the independent prognostic value of post-operative serum C-reactive protein (CRP), a highly sensitive biomarker of inflammation, for long-term CRC outcomes in two large patient cohorts.

MATERIALS AND METHODS

CRP levels were measured from serum samples of CRC patients collected ≥1 month post-surgery in the German DACHS (n = 1416) and the UK Biobank (n = 1149) cohorts. Associations of post-operative CRP with overall survival (OS) and CRC-specific survival (CSS) were assessed using Cox regression and presented as hazard ratios (HRs) with 95% confidence intervals (CIs), adjusted for key sociodemographic and clinical covariates.

RESULTS

In both cohorts, consistent strong dose-response relationships between post-operative CRP and both OS and CSS were observed. Adjusted HRs (95% CI) for CRP >10 versus <3 mg/l were 1.93 (1.58-2.35) and 2.70 (2.03-3.59) in the DACHS cohort, and 2.70 (1.96-3.71) and 2.61 (1.83-3.72) in the UK Biobank cohort, respectively. Associations between post-operative CRP and OS were particularly strong among younger patients (<65 years at diagnosis; P value for interaction by age <0.01).

CONCLUSIONS

Serum CRP determined a month or more after surgery may be useful as a strong independent prognostic biomarker for guiding therapeutic decisions and for surveillance of the course of disease of CRC patients, particularly those <65 years of age at diagnosis.

Social Determinants of Health and the Link to Colorectal Cancer Outcomes

OPINION  STATEMENT: Colorectal cancer (CRC) remains the second most deadly cancer in the United States, behind only lung cancer. Despite improvements in incidence due to screening and mortality in part due to better treatments, there are some groups that have not seen these promising changes. American Indian/Alaska Native and non-Hispanic Black individuals, certain geographic regions, and lower socioeconomic groups have all been shown to have worse CRC outcomes. A significant body of evidence has linked these disparities in outcomes to social determinants of health (SDH). SDH are defined by the WHO as "the non-medical factors that influence health outcomes." These factors include but are not limited to income, education, social support, neighborhood of residence, and access to healthcare. Individuals who are negatively impacted by SDH have been shown to have a higher incidence of CRC. These individuals are also less likely to receive adequate CRC screening, are less likely to receive appropriate treatment, and have increased CRC mortality. Interventions that target different SDH domains have been shown to lead to increased rates of CRC screening and receipt of appropriate treatment while simultaneously improving CRC mortality. The aim of this review is to highlight the connection between SDH and CRC outcomes while also exploring interventions that target SDH and thereby improve CRC outcomes.

Screening for Colorectal Cancer

Colorectal cancer (CRC) is the second leading cause of cancer death. Screening has been proven to reduce both cancer incidence and cancer-related mortality. Various screening tests are available, each with their own advantages and disadvantages and varying levels of evidence to support their use. Clinicians should offer CRC screening to average-risk persons aged 50 to 75 years; starting screening at age 45 years remains controversial. Screening may be beneficial in select persons aged 76 to 85 years, based on their overall health and screening history. Offering a choice of screening tests or sequentially offering an alternate test for those who do not complete screening can significantly increase participation.

Effectiveness of immune checkpoint inhibitors in combination with tyrosine kinase inhibitors in patients with advanced or metastatic colorectal carcinoma with either mismatch repair proficient or metastatic microsatellite stable disease: A systematic review and meta‑analysis

Immune checkpoint inhibitors (ICIs) have limited efficacy in mismatch repair proficient (pMMR) or metastatic microsatellite stable (MSS) advanced or metastatic colorectal cancer (mCRC). ICIs, in conjunction with tyrosine kinase inhibitors (TKIs) possessing anti-angiogenic properties, serve as a potential strategy for circumventing the resistance exhibited by MSS or pMMR mCRC to immunotherapeutic interventions. The present study aimed to evaluate efficacy and safety of ICIs + TKIs and provide a reference for the treatment of CRC. The present systematic review and meta-analysis was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. PubMed, Embase, Cochrane, Web of Science and ClinicalTrials.gov databases were screened from January 1, 2003 to July 28, 2023. A total of 14 studies were included in qualitative and quantitative analyses, with a total of 819 patients enrolled. The Newcastle-Ottawa scale scores of the 14 cohort studies included were ≥7, indicating they were of a high quality. The objective response rate (ORR) of ICIs + TKIs was 14% [95% confidence interval (CI), 0.08-0.24; P=0.132] in patients with advanced or metastatic MSS/pMMR CRC. The disease control rate (DCR) was 65% (95% CI, 0.58-0.74; P<0.0001). The overall incidence of adverse events of varying severity linked to combination of ICIs and TKIs in patients with advanced or metastatic MSS/pMMR CRC was 64% (95% CI, 0.52-0.78; P<0.0001). The incidence of grade ≥3 adverse reactions was 24% (95% CI, 0.14-0.4; P<0.0001). The sensitivity analysis indicated that the exclusion of individual studies did not yield statistically significant variations in combined analysis results. Based on the examination of publication bias, ORR and DCR, Begg's and Egger's tests had P-values of 0.114 and 0.395, respectively. Overall publication bias overall was absent in the Begg's funnel plot, as there was no apparent asymmetry. Nonetheless, the P-values of the Egger's and Begg's tests for adverse reactions and adverse reactions grade ≥3 were P=0.008 and P=0.048, respectively. The asymmetry of the Begg's funnel plots was evident, suggesting the presence of potential publication bias regarding adverse event results. In conclusion, the combination of ICIs and TKIs demonstrates a favorable effectiveness and notable safety profile in the management of patients with advanced or metastatic MSS/pMMR CRC.

Age-related trends in colorectal cancer diagnosis: focus on evaluation of prehabilitation and rehabilitation programs

Abstract: The increase in the prevalence of both colon and rectal cancer in recent years poses challenges for the medical system in terms of patient management and indirectly incurs significant financial burdens. Purpose: The aim of this paper is to track the changes in the prevalance of the colon and rectal cancer at a tertiary clinic in Romania over time and to identify complementary methods to improve the prognosis and quality of life of cancer patients. Material and methods: We conducted an observational, longitudinal, population-based study, including all patients newly diagnosed with colon or rectal neoplasia within the time frame from 1 January 2013 to 1 January 2024 in a tertiary medical clinic in Romania. For each case included in the study, we gathered demographic data (age at the time of cancer diagnosis, gender, place of origin), location of the tumor, duration until surgical intervention, alternative treatment methods employed (such as ra-diation or chemotherapy, and immunotherapy), and the length of survival. We also assess the feasiblity of physical prehabilitation and rehabilitation programs for inpatients diagnosed with malignant neoplasms of the colon or rectum. Results: The study found significant differences in patient ages and the execution of prehabilitation and rehabilitation practices between those ad-mitted for colon and rectal cancer during the periods 2013-2018 and 2019-2023, with a notable shift in the prevalence of colon versus rectal cancer over these periods. Conclusions: Prehabilitation and rehabilitation practices for colorectal cancer patients are underdocumented or suboptimal, with recent improvements in documentation, especially for rectal cancer due to colostomy needs, and an observed increase in patient age due to COVID-19 pandemic protocols. Additional research and the development of standardized protocols are needed.

Ataxia telangiectasia and Rad3-related (ATR) inhibition by VE-822 potently reversed 5-flourouracil resistance in colorectal cancer cells through targeting DNA damage response

BACKGROUND

VE-822 is a novel inhibitor of ATR, a key kinase involved in the DNA damage response pathway. The role of ATR inhibition in reversing drug resistance in various cancer types has been investigated. Therefore, this study investigated the effects of ATR inhibition by VE-822 on reversing 5-fluorouracil (5-FU) resistance in colorectal cancer cell line (Caco-2).

METHODS

Caco-2 and 5-FU resistance Caco-2 (Caco-2/5-FU) cells were treated with 5-FU and VE-822, alone and in combination. Cell proliferation and viability were assessed by MTT assay and Trypan Blue staining. P-glycoprotein (P-gp) and multidrug resistance-associated protein 1 (MRP1) activities were measured by Rhodamine123 accumulation and uptake assay. The mRNA levels of P-gp, MRP-1, ataxia telangiectasia and Rad3-related (ATR) and checkpoint kinase 1 (CHK1) were measured by qRT-PCR. Western blot was used to measure the protein levels of P-gp, MRP-1, γ-H2AX, ATR and CHK1 in cells. 8-Oxo-2'-deoxyguanosine (8-oxo-dG) levels were determined via ELISA. Apoptosis was evaluated by ELISA death assay, DAPI staining and lactate dehydrogenase (LDH) assay.

RESULTS

The Caco-2/5-FU cells showed lower levels of 5-FU mediated proliferation inhibition in comparison to Caco-2 cells. VE-822 decreased the IC50 value of 5-FU on resistant cells. In addition, the expression levels and activity of P-gp and MRP-1 were significantly decreased in resistant cells treated with VE-822 (P < 0.05). The combination of 5-FU and VE-822 increased apoptosis in Caco-2/5-FU cells by downregulating CHK1 and ATR and upregulating γ-H2AX and 8-oxo-dG.

CONCLUSION

The simultaneous treatment of resistant colorectal cancer cells with 5-FU and ATR inhibitor, VE-822, was demonstrated to be effective in reversing drug resistance and potentiating 5-FU mediated anticancer effects via targeting DNA damage.

High Oestrogen receptor alpha expression correlates with adverse prognosis and promotes metastasis in colorectal cancer

In normal colon tissue, oestrogen receptor alpha (ERα) is expressed at low levels, while oestrogen receptor beta (ERβ) is considered the dominant subtype. However, in colon carcinomas, the ERα/β ratio is often increased, an observation that prompted us to further investigate ERα's role in colorectal cancer (CRC). Here, we assessed ERα nuclear expression in 351 CRC patients. Among them, 119 exhibited positive ERα nuclear expression, which was significantly higher in cancer tissues than in matched normal tissues. Importantly, patients with positive nuclear ERα expression had a poor prognosis. Furthermore, positive ERα expression correlated with increased levels of the G-protein coupled cysteinyl leukotriene receptor 1 (CysLT1R) and nuclear β-catenin, both known tumour promoters. In mouse models, ERα expression was decreased in Cysltr1-/- CAC (colitis-associated colon cancer) mice but increased in ApcMin/+ mice with wild-type Cysltr1. In cell experiments, an ERα-specific agonist (PPT) increased cell survival via WNT/β-catenin signalling. ERα activation also promoted metastasis in a zebrafish xenograft model by affecting the tight junction proteins ZO-1 and Occludin. Pharmacological blockade or siRNA silencing of ERα limited cell survival and metastasis while restoring tight junction protein expression. In conclusion, these findings highlight the potential of ERα as a prognostic marker for CRC and its role in metastasis.

Feasibility and safety of minimally invasive multivisceral resection for T4b rectal cancer: A 9-year review

BACKGROUND

Colorectal cancer is the third most common cancer and the second highest cause of cancer-related mortality worldwide. About 5%-10% of patients are diagnosed with locally advanced rectal cancer (LARC) on presentation. For LARC invading into other structures (i.e. T4b), multivisceral resection (MVR) and/or pelvic exenteration (PE) remains the only potential curative surgical treatment. MVR and/or PE is a major and complex surgery with high post-operative morbidity. Minimally invasive surgery (MIS) has been shown to improve short-term post-operative outcomes in other gastrointestinal malignancies, but there is little evidence on its use in MVR, especially so for robotic MVR.

AIM

To assess the feasibility and safety of minimally invasive MVR (miMVR), and compare post-operative outcomes between robotic and laparoscopic MVR.

METHODS

This is a single-center retrospective cohort study from 1st January 2015 to 31st March 2023. Inclusion criteria were patients diagnosed with cT4b rectal cancer and underwent MVR, or stage 4 disease with resectable systemic metastases. Patients who underwent curative MVR for locally recurrent rectal cancer, or metachronous rectal cancer were also included. Exclusion criteria were patients with systemic metastases with non-resectable disease. All patients planned for elective surgery were enrolled into the standard enhanced recovery after surgery pathway with standard peri-operative management for colorectal surgery. Complex surgery was defined based on technical difficulty of surgery (i.e. total PE, bladder-sparing prostatectomy, pelvic lymph node dissection or need for flap creation). Our primary outcomes were the margin status, and complication rates. Categorical values were described as percentages and analysed by the chi-square test. Continuous variables were expressed as median (range) and analysed by Mann-Whitney U test. Cumulative overall survival (OS) and recurrence-free survival (RFS) were analysed using Kaplan-Meier estimates with life table analysis. Log-rank test was performed to determine statistical significance between cumulative estimates. Statistical significance was defined as P < 0.05.

RESULTS

A total of 46 patients were included in this study [open MVR (oMVR): 12 (26.1%), miMVR: 36 (73.9%)]. Patients' American Society of Anesthesiologists score, body mass index and co-morbidities were comparable between oMVR and miMVR. There is an increasing trend towards robotic MVR from 2015 to 2023. MiMVR was associated with lower estimated blood loss (EBL) (median 450 vs 1200 mL, P = 0.008), major morbidity (14.7% vs 50.0%, P = 0.014), post-operative intra-abdominal collections (11.8% vs 50.0%, P = 0.006), post-operative ileus (32.4% vs 66.7%, P = 0.04) and surgical site infection (11.8% vs 50.0%, P = 0.006) compared with oMVR. Length of stay was also shorter for miMVR compared with oMVR (median 10 vs 30 d, P = 0.001). Oncological outcomes-R0 resection, recurrence, OS and RFS were comparable between miMVR and oMVR. There was no 30-d mortality. More patients underwent robotic compared with laparoscopic MVR for complex cases (robotic 57.1% vs laparoscopic 7.7%, P = 0.004). The operating time was longer for robotic compared with laparoscopic MVR [robotic: 602 (400-900) min, laparoscopic: Median 455 (275-675) min, P < 0.001]. Incidence of R0 resection was similar (laparoscopic: 84.6% vs robotic: 76.2%, P = 0.555). Overall complication rates, major morbidity rates and 30-d readmission rates were similar between laparoscopic and robotic MVR. Interestingly, 3-year OS (robotic 83.1% vs 58.6%, P = 0.008) and RFS (robotic 72.9% vs 34.3%, P = 0.002) was superior for robotic compared with laparoscopic MVR.

CONCLUSION

MiMVR had lower post-operative complications compared to oMVR. Robotic MVR was also safe, with acceptable post-operative complication rates. Prospective studies should be conducted to compare short-term and long-term outcomes between robotic vs laparoscopic MVR.

Altered lipid metabolism in APC-driven colorectal cancer: the potential for therapeutic intervention

Altered lipid metabolism is a well-recognized feature of solid cancers, including colorectal cancer. In colorectal cancer, upregulation of lipid metabolism contributes to initiation, progression, and metastasis; thus, aberrant lipid metabolism contributes to a poor patient outcome. The inactivating mutation of APC, a vital tumor suppressor in the Wnt signaling pathway, is a key event that occurs early in the majority of colorectal cancer cases. The potential crosstalk between lipid metabolism and APC-driven colorectal cancer is poorly understood. This review collectively highlights and summarizes the limited understanding between mutations in APC and the upregulation of Wnt/beta-catenin signaling and lipid metabolism. The interconnection between APC inactivation and aberrant lipid metabolism activates Wnt/beta-catenin signaling which causes transcriptome, epigenetic, and microbiome changes to promote colorectal cancer initiation and progression. Furthermore, the downstream effects of this collaborative effort between aberrant Wnt/beta-catenin signaling and lipid metabolism are enhanced stemness, cellular proliferation, prooncogenic signaling, and survival. Understanding the mechanistic link between APC inactivation and alterations in lipid metabolism may foster identification of new therapeutic targets to enable development of more efficacious strategies for prevention and/or treatment of colorectal cancer.

Elevated postoperative carcinoembryonic antigen guides adjuvant chemotherapy for stage II colon cancer: a multicentre cohort retrospective study

Most clinical doctors rely on high-risk factors recommended by guidelines to decide whether to undergo adjuvant chemotherapy for stage II colon cancer. However, these high-risk factors do not include postoperative carcinoembryonic antigen (CEA). This study aims to explore the elevation of postoperative CEA as a risk factor, in addition to other high-risk factors, to guide adjuvant chemotherapy for patients with stage II colon cancer. A retrospective analysis was conducted on stage II colon cancer patients who underwent curative surgery at Yunnan Cancer Hospital and The Sixth Affiliated Hospital of Sun Yat-Sen University from April 2008 to January 2019. Patients were classified into three groups based on high-risk factors recommended by guidelines and postoperative CEA levels: low-risk with normal postoperative CEA, low-risk with elevated postoperative CEA and high-risk. COX regression analysis was used to identify independent prognostic factors affecting patients' recurrence free survival (RFS). The Kaplan-Meier method was used to create the patients' RFS curve. The restricted cubic spline (RCS) curve was used to assess the correlation between postoperative CEA and RFS on a continuous scale. Among 761 patients, there were 444 males (62.01%), with a median [IQR] age of 58.0 (18.0-88.0) years. A group of 425 high-risk patients had a 3-year RFS of 82.2% (95% CI 78.5-86.1%), while a group of 291 low-risk patients had a 3-year RFS of 89.7% (95% CI 86.1-93.5%). There was a statistically significant difference between the two groups (HR 1.83; 95% CI 1.22-2.74; P = 0.0067). Among them, the 3-year RFS of 261 low-risk patients with normal postoperative CEA was 93.6% (95% CI 90.5-96.8%), while the 3-year RFS of 30 low-risk patients with elevated postoperative CEA was 57.3% (95% CI 41.8-71.4%). There was a significant difference compared to the 3-year RFS of 425 high-risk patients (overall log-rank P < 0.0001). The multivariate analysis adjusted by the COX proportional hazards model showed that low-risk patients with elevated postoperative CEA patients (HR 14.95, 95% CI 4.51-49.63, P < 0.0001) was independently associated with a 3-year RFS. The restricted cubic spline model showed that in stage II colon cancer patients with tumor diameter > 1.955 ng/mL, the risk of postoperative recurrence increased with increasing postoperative CEA levels. Patients with elevated postoperative CEA levels have a significantly increased risk of recurrence. They should be included as high-risk factors to guide adjuvant chemotherapy for stage II colon cancer.