Colorectal carcinoma: diagnostic, prognostic, and molecular features

Protein structure prediction via deep learning: an in-depth review

The application of deep learning algorithms in protein structure prediction has greatly influenced drug discovery and development. Accurate protein structures are crucial for understanding biological processes and designing effective therapeutics. Traditionally, experimental methods like X-ray crystallography, nuclear magnetic resonance, and cryo-electron microscopy have been the gold standard for determining protein structures. However, these approaches are often costly, inefficient, and time-consuming. At the same time, the number of known protein sequences far exceeds the number of experimentally determined structures, creating a gap that necessitates the use of computational approaches. Deep learning has emerged as a promising solution to address this challenge over the past decade. This review provides a comprehensive guide to applying deep learning methodologies and tools in protein structure prediction. We initially outline the databases related to the protein structure prediction, then delve into the recently developed large language models as well as state-of-the-art deep learning-based methods. The review concludes with a perspective on the future of predicting protein structure, highlighting potential challenges and opportunities.

Prognostic and predictive value of tumor infiltration proportion within lymph nodes in N1 colorectal cancer

Introduction

Lymph node metastasis is a crucial determinant of prognosis in colorectal cancer (CRC), significantly impacting survival outcomes and treatment decision-making. This study aims to evaluate the prognostic value of tumor infiltration proportion within lymph nodes (TIPLN) in N1 CRC patients and to develop a TIPLN-based nomogram to predict prognosis.

Methods

A total of 416 N1 CRC patients who underwent radical resection were enrolled and divided into training and validation cohorts. Whole-slide images of lymph nodes were annotated to assess the TIPLN. Univariable and multivariable Cox regression analyses were conducted to identify independent prognostic factors and to develop a nomogram for predicting patient outcomes. The precision and discrimination of the nomogram were evaluated using the area under the receiver operating characteristic curve (AUC), concordance index (C-index), and calibration curve. Decision curve analysis (DCA) was performed to compare the net benefit of the nomogram at different threshold probabilities. Additionally, net reclassification index (NRI) and integrated discrimination improvement (IDI) were used to evaluate the nomogram's clinical utility.

Results

High TIPLN levels were significantly associated with poorer overall survival (OS). Five variables, including TIPLN, were selected to construct the nomogram. The C-index in OS prediction was 0.739 and 0.753 for the training and validation cohorts, respectively. Additionally, strong precision and discrimination were demonstrated through AUC and calibration curves. The NRI (training cohort: 0.191 for 3-year and 0.436 for 5-year OS prediction; validation cohort: 0.180 for 3-year and 0.439 for 5-year OS prediction) and IDI (training cohort: 0.079 for 3-year and 0.094 for 5-year OS prediction; validation cohort: 0.078 for 3-year and 0.098 for 5-year OS prediction) suggest that the TIPLN-based nomogram significantly outperformed the clinicopathological nomogram. Furthermore, DCA demonstrated the high clinical applicability of the TIPLN-based nomogram for predicting OS.

Conclusions

TIPLN could serve as a prognostic predictor for N1 CRC patients. The TIPLN-based nomogram enhances survival prediction accuracy and facilitates more informed, individualized clinical decision-making.

A fusion model to predict the survival of colorectal cancer based on histopathological image and gene mutation

Colorectal cancer (CRC) is a prevalent gastrointestinal tumor worldwide with high morbidity and mortality. Predicting the survival of CRC patients not only enhances understanding of their life expectancies but also aids clinicians in making informed decisions regarding suitable adjuvant treatments. Although there are many clinical, genomic, and transcriptomic studies on this hot topic, only a few studies have explored the direction of integrating advanced deep learning algorithms and histopathological images. In addition, it is still unclear if combining histopathological images and molecular data can better predict patients' survival. To fill in this gap, we proposed in this study a novel multimodal deep learning computational framework using Multimodal Compact Bilinear Pooling (MCBP) to predict the 5-year survival of CRC patients from histopathological images, clinical information, and molecular data. We applied our framework to the cancer genome atlas (TCGA) CRC data, consisting of 84 samples with histopathological images, clinical information, mRNA sequencing data, and gene mutation data all available. Under the 5-fold cross-validation, the model using only histopathological images achieved an area under the curve (AUC) of 0.743. Whereas, the model combining image and clinical information and the model combining image and gene mutation information achieved AUCs of 0.771 and 0.773 respectively, better than that of the image solely. Our study demonstrates that histopathological images can reasonably predict the 5-year survival of CRC patients, and that the appropriate integration of these images with clinical or molecular data can further enhance predictive performance.

Early Rectal Cancer: Advances in Diagnosis and Management Strategies

Colorectal cancer (CRC) is the second most prevalent cause of cancer-related death and the third most common cancer globally. Early-stage rectal cancer is defined by lesions confined to the bowel wall, without extension beyond the submucosa in T1 or the muscularis propria in T2, with no indication of lymph node involvement or distant metastasis. The gold standard for managing rectal cancer is total mesorectal excision (TME); however, it is linked to considerable morbidities and impaired quality of life. There is a growing interest in local resection and non-operative treatment of early RC for organ preservation. Local resection options include three types of transanal endoscopic surgery (TES): transanal endoscopic microsurgery (TEM), transanal endoscopic operations (TEO), and transanal minimally invasive surgery (TAMIS), while endoscopic resection includes endoscopic mucosal resection (EMR), underwater endoscopic mucosal resection (UEMR), and endoscopic submucosal dissection (ESD). Although the oncological outcome of local resection of early rectal cancer is debated in the current literature, some studies have shown comparable outcomes with radical surgery in selected patients. The use of adjuvant and neoadjuvant chemoradiotherapy in early rectal cancer management is also controversial in the literature, but a number of studies have reported promising outcomes. This review focuses on the available literature regarding diagnosis, staging, and management strategies of early rectal cancer and provides possible recommendations.

Analysis of exportins expression unveils their prognostic significance in colon adenocarcinoma: insights from public databases

Colon cancer remains a significant health burden globally, necessitating deeper investigation. Identification and targeting of prognostic markers can significantly improve the current therapeutic approaches for colon cancer. The differential nuclear transport (import and export) of cellular proteins, plays an important role in tumor progression. Exportins, critical mediators of nuclear export, have emerged as potential players in cancer pathogenesis. However, their precise roles and prognostic significance in colon adenocarcinoma remain elusive. This study was designed to comprehensively analyse the expression and prognostic significance of all seven exportins in Colon Adenocarcinoma (COAD) using the online public database. We used public databases UALCAN, C-Bio portal, Human Protein Atlas (HPA), and DAVID, to investigate exportins in COAD patients. Kaplan-Meier plotter, Gene ontology (GO), TIMER, STRING, and KEGG were used to analyse data and draw conclusions. Our observations showed a significant correlation of exportins expression with clinical parameters, used to predict a patient's prognosis in general, such as advancing tumor stage, overall/relapse-free survival, and immune cell infiltrations. Mutation analysis showed the presence of amplifications, missense mutations in XPO2 and XPO4, and deep deletions in XPO7 genes contributing to disease progression and patients survival. This study highlights the potential use of exportins as novel prognostic biomarkers and therapeutic targets for colon adenocarcinoma progression and management.

Evaluation of colon cancer prognostic factors by CT and MRI: an up-to-date review

Colorectal cancer (CRC) is a significant global health concern. Prognostication of CRC traditionally relies on the Union for International Cancer Control (UICC) and American Joint Committee on Cancer (AJCC) TNM staging classifications, yet clinical outcomes often vary independently of stage. Despite similarities, rectal and colon cancers are distinct in their diagnostic methodologies and treatments, with MRI and CT scans primarily used for staging rectal and colon cancers, respectively. This paper examines the challenges in accurately assessing prognostic factors of colon cancer such as primary tumor extramural extension, retroperitoneal surgical margin (RSM) involvement, extramural vessel invasion (EMVI), and lymph node metastases through preoperative CT and MRI. It highlights the importance of these factors in risk stratification, treatment decisions, and surgical planning for colon cancer patients. Advancements in imaging techniques are crucial for improving clinical management and optimizing patient outcomes, underscoring the necessity for ongoing research to refine diagnostic methods and incorporate novel findings into practice.

Exploring prognostic biomarkers in pathological images of colorectal cancer patients via deep learning

Hematoxylin and eosin (H&E) whole slide images provide valuable information for predicting prognostic outcomes in colorectal cancer (CRC) patients. However, extracting prognostic indicators from pathological images is challenging due to the subtle complexities of phenotypic information. We trained a weakly supervised deep learning model on data from 640 CRC patients in the prostate, lung, colorectal, and ovarian (PLCO) cancer screening trial dataset and validated it using data from 522 CRC patients in the cancer genome atlas (TCGA) dataset. We created the colorectal cancer risk score (CRCRS) to assess patient prognosis, visualized the pathological phenotype of the risk score using Grad-CAM, and employed multiomics data from the TCGA CRC cohort to investigate the potential biological mechanisms underlying the risk score. The overall survival analysis revealed that the CRCRS served as an independent prognostic indicator for both the PLCO cohort (p < 0.001) and the TCGA cohort (p < 0.001), with its predictive efficacy remaining unaffected by the clinical staging system. Additionally, satisfactory chemotherapeutic benefits were observed in stage II/III CRC patients with high CRCRS but not in those with low CRCRS. A pathomics nomogram constructed by integrating the CRCRS with the tumor-node-metastasis (TNM) staging system enhanced prognostic prediction accuracy compared with using the TNM staging system alone. Noteworthy features of the risk score were identified, such as immature tumor mesenchyme, disorganized gland structures, small clusters of cancer cells associated with unfavorable prognosis, and infiltrating inflammatory cells associated with favorable prognosis. The TCGA multiomics data revealed potential correlations between the CRCRS and the activation of energy production and metabolic pathways, the tumor immune microenvironment, and genetic mutations in APC, SMAD2, EEF1AKMT4, EPG5, and TANC1. In summary, our deep learning algorithm identified the CRCRS as a prognostic indicator in CRC, providing a significant approach for prognostic risk stratification and tailoring precise treatment strategies for individual patients.

Clinical evaluation of sintilimab in conjunction with bevacizumab for advanced colorectal cancer with microsatellite stable-type after failure of first-line therapy

BACKGROUND

At present, immune checkpoint inhibitors (ICIs) remain the 1st-line therapy method for patients suffering from high microsatellite instability /deficient mismatch repair metastatic colorectal cancer (mCRC). However, ICI treatments demonstrate minimal therapeutic efficacy against microsatellite stable (MSS)/proficient mismatch repair (pMMR) CRC. This is mainly because this type of tumor is a "cold tumor" with almost no lymphocyte infiltration. Anti-angiogenic drugs have been found to improve the immune microenvironment by promoting many immune cells to enter the immune microenvironment, thereby exerting anti-tumor effects.

AIM

To investigate the effects of ICIs combined with bevacizumab monoclonal antibody on tumor immune cells in MSS/pMMR advanced CRC patients with first-line treatment failure.

METHODS

A total of 110 MSS/pMMR patients with advanced CRC after first-line treatment failure in the Affiliated Hospital of Qinghai University were enrolled for a randomized controlled trial. In short, patients in the experimental group (n = 60) were given sintilimab plus bevacizumab for 4 cycles, and those in the control group (n = 50) patients were treated with FOLFIRI combined with bevacizumab for 4 cycles. The expression levels of cluster of differentiation (CD) 8 (+) T cells, tumor-associated macrophages (TAMs), and cancer-associated fibroblasts (CAFs) were comprehensively evaluated to assess the effects of sintilimab combined with bevacizumab on MSS/pMMR advanced CRC sufferers following failure of 1st-line therapy.

RESULTS

The positive expression rates of CD8 (+) T lymphocytes (30% vs 50%), TAMs (23.30% vs 60%), and CAFs (23.30% vs 50%) before and after treatment in both groups exhibited statistical significance (P < 0.05). Additionally, the therapeutic effects of both groups (partial remission: 26.67% vs 10%; objective response rate: 26.70% vs 10%) were significantly different (P < 0.05). Although the experimental group showed a higher progression-free survival, median progression-free survival, and disease control rate than the control group, the difference was not statistically significant. Moreover, no significant difference in the occurrence rate of drug-related adverse reactions after treatment between the two groups was found (P > 0.05).

CONCLUSION

ICIs in combination with bevacizumab can not only improve the patient's prognosis but also yield safe and controllable adverse drug reactions in patients suffering from MSS/pMMR advanced CRC after failure to a 1st-line therapy.

The clinical significance of elastic lamina invasion in patients with pStage II colorectal cancer: a notable prognostic indicator

BACKGROUND

Some colorectal cancers (CRCs) are clinically diagnosed as cT4a with　serosal invasion (SI). However, the cT4a is most often underdiagnosed pathologically as pT3 without SI by hematoxylin-eosin (H&E) staining alone. Using Elastica van Gieson (EVG) staining, some pT3 tumors invade the elastic lamina (EL), which extends just below the serosal layer. Recently, EL invasion (ELI) has been described as a poor prognostic factor for disease-free survival (DFS) and overall survival (OS) in patients with pStage II CRC. However, its clinicopathological significance remains unclear due to the limited number of studies and poor understanding of ELI.

OBJECTIVE

This study investigated the association between the ELI and patient prognosis.

METHODS

After 1982, pathological diagnosis was routinely performed using H&E and EVG staining methods, and long-term follow up was performed until 2016. All clinicopathological features including ELI were prospectively registered into our computer and 569 patients with pStage II CRC were collected from the database. Based on the ELI status, pT3 was divided into three pathological categories: pT3ELI - was defined as pT3a, pT3ELI + as pT3b and unidentified EL (pT3EL -) as pT3u.

RESULTS

Using H&E staining alone, gross cT4a was most often pathologically underdiagnosed as pT3 (93.8%) and very rarely as pT4a, resulting in a large diagnostic discrepancy. Using EVG staining, 60.7% of the cT4a tumors were diagnosed as pT3b. The 10-year DFS and OS rates were similar for pT3a and pT3u patients. However, the 10-year DFS and OS rates of pT3b patients were significantly lower than those of pT3a patients (75.6% vs. 95.6%, p < 0.0001 and 58.4% vs. 70.6%, p = 0.0024, respectively) but did not differ from those of pT4a patients (70.6%, p = 0.5799 and 52.0%, p = 0.1116, respectively). Multivariate analysis revealed that the ELI was the strongest independent risk factor for recurrence and CRC-specific death (p < 0.0001).

CONCLUSIONS

A better understanding of the ELI allows us to reconsider the diagnostic discrepancy of serosal invasion, i.e., pT3b should be considered pT4a. The ELI-based subclassification of pT3 is expected to be incorporated into the TNM staging system in the future. The ELI is a notable prognostic indicator in patients with pStage II CRC.

Mucinous histology is a negative predictor of neoadjuvant chemoradiotherapy for locally advanced rectal adenocarcinoma

BACKGROUND

Neoadjuvant chemoradiotherapy (NCRT) followed by total mesorectal excision (TME) is the standard treatment for locally advanced rectal cancer (LARC). Mucinous adenocarcinoma (MAC) is a potential poor prognosis subgroup of rectal cancer. However, the predictive value of MAC in NCRT treatment of LARC is controversial.

METHODS

A comprehensive literature search of PubMed, Embase, and the Cochrane Library was performed. All studies examining the effect of MAC on CRT response in LARC were included. Outcomes of MAC were compared with non-specific adenocarcinoma (AC) by using random-effects methods. Data were presented as odds ratios (ORs) with 95% confidence intervals (CIs). The main outcomes were the rates of pathological complete response (pCR), tumor and nodal down-staging, positive resection margin rate, local recurrence, and overall mortality.

RESULTS

Fifteen studies containing comparative data on outcomes in a total of 9,238 patients receiving NCRT for LARC were eligible for inclusion. MAC had a reduced rate of pCR (OR, 0.38; 95% CI, 0.18-0.78) and tumor down-staging (OR, 0.31; 95% CI, 0.22-0.44) following NCRT compared with AC. MAC did not significantly affect nodal down-staging (OR, 0.42; 95% CI, 0.16-1.12) after NCRT.

CONCLUSION

MAC of LARC was found to be a negative predictor of response to NCRT with lower rates of pCR and tumor down-staging for LARC. The nodal down-staging of MAC was relatively lower than that of AC, although the differences were not statistically significant.

Transcription factor ZEB1 coordinating with NuRD complex to promote oncogenesis through glycolysis in colorectal cancer

Background

Colorectal cancer (CRC) is an aggressive primary intestinal malignancy with the third-highest incidence and second-highest mortality among all cancer types worldwide. Transcription factors (TFs) regulate cell development and differentiation owing to their ability to recognize specific DNA sequences upstream of genes. Numerous studies have demonstrated a strong correlation between TFs, the etiology of tumors, and therapeutic approaches. Here, we aimed to explore prognosis-related TFs and comprehend their carcinogenic mechanisms, thereby offering novel insights into the diagnosis and management of CRC.

Materials and Methods

Differentially expressed TFs between CRC and normal tissues were identified leveraging The Cancer Genome Atlas database, Weighted correlation network analysis and Cox regression analysis were performed to identify prognosis-related TFs. The cellular functions of hub TF zinc finger E-box binding homeobox 1 (ZEB1) were determined using by 5-ethynyl-2'-deoxyuridine and cell invasion assays in CRC cells. RNA-sequencing, Kyoto Encyclopedia of Genes and Genomes enrichment, and gene set enrichment analyses were used to identify the cellular processes in which ZEB1 participates. Immunoaffinity purification, silver staining mass spectrometry, and a chromatin immunoprecipitation assay were conducted to search for proteins that might interact with ZEB1 and the target genes they jointly regulate.

Results

Thirteen central TFs related to prognosis were identified through bioinformatics analysis techniques. Among these TFs, ZEB1 emerged as the TF most closely associated with CRC, as determined through a combination of regulatory network diagrams, survival curves, and phenotype analyses. ZEB1 promotes CRC cell growth by recruiting the NuRD(MTA1) complex, and the ZEB1/NuRD(MTA1) complex transcriptionally represses glycolysis-associated tumor suppressor genes.

Conclusion

Our study not only identified a hub biomarker related to CRC prognosis but also revealed the specific molecular mechanisms through which ZEB1 affects cancer progression. These insights provide crucial evidence for the diagnosis of CRC and potential treatment opportunities.

The histological and molecular characteristics of early-onset colorectal cancer: a systematic review and meta-analysis

Background

Early-onset colorectal cancer (CRC), defined as diagnosis before age 50, has increased in recent decades. Although more often diagnosed at advanced stage, associations with other histological and molecular markers that impact prognosis and treatment remain to be clarified. We conducted a systematic review and meta-analysis concerning the prevalence of prognostic and predictive tumor markers for early- vs. late-onset CRC, including oncogene mutations, microsatellite instability (MSI), and emerging markers including immune cells and the consensus molecular subtypes.

Methods

We systematically searched PubMed for original research articles published between April 2013-January 2024. Included studies compared the prevalence of tumor markers in early- vs. late-onset CRC. A meta-analysis was completed and summary odds ratios (ORs) with 95% confidence intervals (CIs) were obtained from a random effects model via inverse variance weighting. A sensitivity analysis was completed to restrict the meta-analysis to studies that excluded individuals with Lynch syndrome, a hereditary condition that influences the distribution of tumor markers for early-onset CRC.

Results

In total, 149 articles were identified. Tumors from early-onset CRC are less likely to include mutations in KRAS (OR, 95% CI: 0.91, 0.85-0.98), BRAF (0.63, 0.51-0.78), APC (0.70, 0.58-0.84), and NRAS (0.88, 0.78-1.00) but more likely to include mutations in PTEN (1.68, 1.04-2.73) and TP53 (1.34, 1.24-1.45). After limiting to studies that excluded Lynch syndrome, the associations between early-onset CRC and BRAF (0.77, 0.64-0.92) and APC mutation (0.81, 0.67-0.97) were attenuated, while an inverse association with PIK3CA mutation was also observed (0.88, 0.78-0.99). Early-onset tumors are less likely to develop along the CpG Island Methylator Phenotype pathway (0.24, 0.10-0.57), but more likely to possess adverse histological features including high tumor grade (1.20, 1.15-1.25), and mucinous (1.22, 1.16-1.27) or signet ring histology (2.32, 2.08-2.57). A positive association with MSI status (1.31, 1.11-1.56) was also identified. Associations with immune markers and the consensus molecular subtypes are inconsistent.

Discussion

A lower prevalence of mutations in KRAS and BRAF is consistent with extended survival and superior response to targeted therapies for metastatic disease. Conversely, early-onset CRC is associated with aggressive histological subtypes and TP53 and PTEN mutations, which may serve as therapeutic targets.

Racial disparities in colorectal cancer clinicopathological and molecular tumor characteristics: a systematic review

PURPOSE

African Americans have the highest colorectal cancer (CRC) mortality of all racial groups in the USA, which may relate to differences in healthcare access or advanced stage at diagnosis. Recent evidence indicates that differences in tumor characteristics may also underlie disparities in mortality. To highlight recent findings and areas for investigation, we completed the first systematic review of racial disparities in CRC tumor prognostic markers, including clinicopathological markers, microsatellite instability (MSI), oncogene mutations, and novel markers, including cancer stem cells and immune markers.

METHODS

Relevant studies were identified via PubMed, limited to original research published within the last 10 years. Ninety-six articles were identified that compared the prevalence of mortality-related CRC tumor characteristics in African Americans (or other African ancestry populations) to White cases.

RESULTS

Tumors from African ancestry cases are approximately 10% more likely to contain mutations in KRAS, which confer elevated mortality and resistance to epidermal growth factor receptor inhibition. Conversely, African Americans have approximately 50% lower odds for BRAF-mutant tumors, which occur less frequently but have similar effects on mortality and therapeutic resistance. There is less consistent evidence supporting disparities in mutations for other oncogenes, including PIK3CA, TP53, APC, NRAS, HER2, and PTEN, although higher rates of PIK3CA mutations and lower prevalence of MSI status for African ancestry cases are supported by recent evidence. Although emerging evidence suggests that immune markers reflecting anti-tumor immunity in the tumor microenvironment may be lower for African American cases, there is insufficient evidence to evaluate disparities in other novel markers, cancer stem cells, microRNAs, and the consensus molecular subtypes.

CONCLUSION

Higher rates of KRAS-mutant tumors in in African Americans may contribute to disparities in CRC mortality. Additional work is required to understand whether emerging markers, including immune cells, underlie the elevated CRC mortality observed for African Americans.

Colorectal Carcinoma and Gluteal Abscesses in the Background of a Gait Disturbance Presentation

Introduction

Profuse diarrhea and abdominal discomfort are well-documented symptoms of patients with known colorectal cancer. It is much less common for these patients to present with a chief complaint of gait disturbance and rhabdomyolysis. We present a case of incidentally discovered colorectal carcinoma in a patient who was initially evaluated for progressive weakness and recurrent falls.

Case Presentation

A 51-year-old man was admitted to our department for management of rhabdomyolysis in the setting of progressive lower extremity weakness and mechanical falls. He developed abdominal discomfort and bowel changes during his admission, and after further investigation, he was found to have a rectal polyp positive for invasive adenocarcinoma, as well as multiple gluteal abscesses. Workup for metastasis, mutations, and oncogenic biomarkers was unremarkable.

Conclusion

This case is a demonstration of a medically complex patient presentation compounded by multifactorial processes. Future providers may take note that an initial absence of classic gastrointestinal (GI) symptoms does not necessarily rule out underlying GI cancer. Instead, the initial presentation of colorectal adenocarcinoma may manifest with paraneoplastic versus incidental progressive proximal limb weakness prior to GI symptoms such as diarrhea. Additionally, our report demonstrates a case of possible paraneoplastic gluteal abscesses, which may have further contributed to the patient's gait disturbance. However, it is unclear as to whether our patient's various symptoms were directly linked to one another, or if they were incidental co-presentations.

Applications of new radiological scores: the Node-rads in colon cancer staging

PURPOSE

The study focuses on the evaluation of the new Node Reporting and Data System 1.0 (Node-rads) scoring accuracy in the assessment of metastatic lymph nodes (LN) in patients with colon carcinoma.

MATERIAL AND METHODS

From April 2021 to May 2022, retrospective chart reviews were performed on 67 preoperative CT (Computed Tomography) of patients undergoing excisional surgery for colon cancer at the Polyclinic of Bari, Italy. Primary endpoints were to assess lymph node size and configuration to express the likelihood of a metastatic site adopting the Node-rads score system, whose categories of risk are defined from 1 (very low) to 5 (very high). The nodal postsurgical histological evaluation was the gold standard. The relationship between Node-rads score, LN size, configuration criteria (texture, border and shape) and the presence of histological metastases was statistically evaluated.

RESULTS

All surgical specimens examined had correlation with Node-rads score. They were significantly more likely to present nodes micrometastasis those patients with (a) spherical LN shape (82.8%), (b) with lymph node necrosis (100%), (c) irregular borders (87%) and (d) the LN short axis more than 10 mm (61.9%).

CONCLUSIONS

Our experience highlights how the Node-rads system proposes an intuitive and effective definition of criteria to standardize the lymph node radiological reports in colon cancer disease. Further studies are needed to streamline the classification of the nodal and peripheral LN in all the oncological imaging.

Evaluation of the Knowledge of the Most Common Cancers Among Health Students at Jazan University, Saudi Arabia: A Cross-Sectional Study

BACKGROUND

Cancer is a major public health problem worldwide, and medical students are expected to have adequate knowledge and awareness of the most common types of cancer. This study aimed to assess the cancer knowledge of medical students at Jazan University, Saudi Arabia, focusing on breast cancer (BC), prostate cancer (PC), cervical cancer (CC), and colorectal cancer (CRC).

METHODS

This study employed a self-administered survey to evaluate both general and specialized knowledge of cancer types. A total of 321 medical students from different academic years participated in the study. The questionnaire used a scoring system where each correct answer was given one point, and each incorrect answer or "I don't know" response was given zero points.

RESULTS

The overall knowledge scores were 18.75 ± 4.43 out of 28 (67%). The students had a good level of general knowledge about cancer (5.26 ± 1.44 out of 7, 75%) and breast cancer (5.47 ± 1.44 out of 7, 78%) and a moderate knowledge level of prostate cancer (2.83 ± 1.07 out of 4, 71%), cervical cancer (2.74 ± 1.53 out of 5, 55%), and colorectal cancer (2.55 ± 1.61 out of 5, 50%). There were significant differences in cancer knowledge by gender, academic year, and having a relative or friend with cancer. All types of cancer knowledge were positively and significantly correlated with each other.

CONCLUSION

This study revealed the strengths and weaknesses of cancer knowledge among medical students at Jazan University, Saudi Arabia. The overall score for knowledge indicated a moderate level. The students had some knowledge about cancer prevention, detection, and treatment, but some gaps and misconceptions need to be addressed. More education and awareness programs are necessary to improve cancer literacy among students and promote healthy behaviors that can reduce cancer risk.

Long-term effect of neoadjuvant radiotherapy in patients with locally advanced rectal mucinous adenocarcinoma: a population-based study of 1514 patients

Rectal mucinous adenocarcinoma (RMAC) is a rare and aggressive form of rectal cancer. The effectiveness of neoadjuvant radiotherapy (NRT) for RMAC has not been well studied, and the survival benefit remains controversial. The purpose of this work was to determine the prognostic role of NRT in patients with RMAC by propensity-score matching (PSM). A retrospective cohort study using the Surveillance, Epidemiology, and End Results from 2004 to 2015 was performed. In the multivariate analysis before PSM, NRT provided better OS (HR 0.61, 95% CI 0.52-0.71, p < 0.001) and CSS (HR 0.68, 95% CI 0.56-0.82, p < 0.001). Multivariate analysis after PSM (n = 844) confirmed that patients receiving NRT survived longer than those without NRT (OS: HR 0.60, 95% CI 0.50-0.78, p < 0.001 and CSS: HR 0.68, 95% CI 0.54-0.84, p < 0.001). Subgroup analysis indicated that NRT had significantly improved OS and CSS in stage II RMAC and OS in stage III RMAC after adjusting for various confounding factors.

A Retrospective Study of the Prognostic Patterns in Colorectal Cancer Patients

Introduction  Colorectal cancer (CRC) management has advanced globally, leading to a steady decline in mortality rates. However, recent studies have shown that the prognosis of CRC varies based on the anatomical site of the primary tumor, histopathological grading, and type of mutation. With an increase in the incidence of CRC globally and in Bahrain, there is a need for a recent descriptive study to improve overall management. This study aims to investigate the anatomical, histopathological, and molecular prognostic factors in CRC patients presenting to the Salmaniya Medical Complex (SMC). Methods  The study was conducted retrospectively using ISEHA electronic database over two years (January 2019 to December 2020). A total of 101 patients with primary CRC registered in the General Surgery Department were included in this study. The sample size was further stratified and analyzed using descriptive statistics based on the available data of measured outcomes. Results  Anatomical data showed that 65% of CRC patients had a tumor on the left side of the colon, 27.7% on the right side, and 7% in the transverse colon. Overall, 16.8% of all patients had rectal involvement. Histopathological data showed that 86% of the patients had a low-grade CRC adenocarcinoma. The most diagnosed tumor stage was pT3N0M0 (22.8%). In addition, there were ten metastatic cases (10 to the liver, of which three had concomitant lung involvement and two had concurrent brain metastases). The average tumor diameter was 46.2 mm, where 63% ranged between 30 mm to 69 mm. Most mutations involved the TP53 (27.7%) and the KRAS (29%) genes.  Conclusion  The study found that majority of CRC patients at SMC in Bahrain had relatively good overall anatomical, tumor staging and grading prognostic factors but somewhat poorer molecular prognostics.

Diatom-Based Nanomedicine for Colorectal Cancer Treatment: New Approaches for Old Challenges

Colorectal cancer is among the most prevalent and lethal cancers globally. To address this emergency, countries have developed diffuse screening programs and innovative surgical techniques with a consequent decrease in mortality rates in non-metastatic patients. However, five years after diagnosis, metastatic CRC is still characterized by less than 20% survival. Most patients with metastatic CRC cannot be surgically treated. For them, the only option is treatment with conventional chemotherapies, which cause harmful side effects in normal tissues. In this context, nanomedicine can help traditional medicine overcome its limits. Diatomite nanoparticles (DNPs) are innovative nano-based drug delivery systems derived from the powder of diatom shells. Diatomite is a porous biosilica largely found in many areas of the world and approved by the Food and Drug Administration (FDA) for pharmaceutical and animal feed formulations. Diatomite nanoparticles with a size between 300 and 400 nm were shown to be biocompatible nanocarriers capable of delivering chemotherapeutic agents against specific targets while reducing off-target effects. This review discusses the treatment of colorectal cancer with conventional methods, highlighting the drawbacks of standard medicine and exploring innovative options based on the use of diatomite-based drug delivery systems. Three targeted treatments are considered: anti-angiogenetic drugs, antimetastatic drugs, and immune checkpoint inhibitors.

Towards targeted colorectal cancer biopsy based on tissue morphology assessment by compression optical coherence elastography

Identifying the precise topography of cancer for targeted biopsy in colonoscopic examination is a challenge in current diagnostic practice. For the first time we demonstrate the use of compression optical coherence elastography (C-OCE) technology as a new functional OCT modality for differentiating between cancerous and non-cancerous tissues in colon and detecting their morphological features on the basis of measurement of tissue elastic properties. The method uses pre-determined stiffness values (Young’s modulus) to distinguish between different morphological structures of normal (mucosa and submucosa), benign tumor (adenoma) and malignant tumor tissue (including cancer cells, gland-like structures, cribriform gland-like structures, stromal fibers, extracellular mucin). After analyzing in excess of fifty tissue samples, a threshold stiffness value of 520 kPa was suggested above which areas of colorectal cancer were detected invariably. A high Pearson correlation (r =0.98; p &lt;0.05), and a negligible bias (0.22) by good agreement of the segmentation results of C-OCE and histological (reference standard) images was demonstrated, indicating the efficiency of C-OCE to identify the precise localization of colorectal cancer and the possibility to perform targeted biopsy. Furthermore, we demonstrated the ability of C-OCE to differentiate morphological subtypes of colorectal cancer – low-grade and high-grade colorectal adenocarcinomas, mucinous adenocarcinoma, and cribriform patterns. The obtained ex vivo results highlight prospects of C-OCE for high-level colon malignancy detection. The future endoscopic use of C-OCE will allow targeted biopsy sampling and simultaneous rapid analysis of the heterogeneous morphology of colon tumors.

Multifactor dimensionality reduction method identifies novel SNP interactions in the WNT protein interaction networks that are associated with recurrence risk in colorectal cancer

Background

Interactions among genetic variants are rarely studied but may explain a part of the variability in patient outcomes.

Objectives

In this study, we aimed to identify 1 to 3 way interactions among SNPs from five Wnt protein interaction networks that predict the 5-year recurrence risk in a cohort of stage I-III colorectal cancer patients.

Methods

423 patients recruited to the Newfoundland Familial Colorectal Cancer Registry were included. Five Wnt family member proteins (Wnt1, Wnt2, Wnt5a, Wnt5b, and Wnt11) were selected. The BioGRID database was used to identify the proteins interacting with each of these proteins. Genotypes of the SNPs located in the interaction network genes were retrieved from a genome-wide SNP genotype data previously obtained in the patient cohort. The GMDR 0.9 program was utilized to examine 1-, 2-, and 3-SNP interactions using a 5-fold cross validation step. Top GMDR 0.9 models were assessed by permutation testing and, if significant, prognostic associations were verified by multivariable logistic regression models.

Results

GMDR 0.9 has identified novel 1, 2, and 3-way SNP interactions associated with 5-year recurrence risk in colorectal cancer. Nine of these interactions were multi loci interactions (2-way or 3-way). Identified interaction models were able to distinguish patients based on their 5-year recurrence-free status in multivariable regression models. The significance of interactions was the highest in the 3-SNP models. Several of the identified SNPs were eQTLs, indicating potential biological roles of the genes they were associated with in colorectal cancer recurrence.

Conclusions

We identified novel interacting genetic variants that associate with 5-year recurrence risk in colorectal cancer. A significant portion of the genes identified were previously linked to colorectal cancer pathogenesis or progression. These variants and genes are of interest for future functional and prognostic studies. Our results provide further evidence for the utility of GMDR models in identifying novel prognostic biomarkers and the biological importance of the Wnt pathways in colorectal cancer.

Molecular, Morphological and Clinical Characteristics of Spontaneous Canine Colorectal Cancer – A Review

Cross-species comparison analysis studies are of immense importance in veterinary and human oncological research. Of the various non-rodent species available, dogs have gained most attention as potential animal models for the study of colorectal cancer. Domestic dogs developed evolutionally through a mutually beneficial relationship with humans. Because dogs share the same environment as humans, they are exposed to the same potentially harmful substances which may act as carcinogens in both species. Intestinal adenocarcinomas in dogs are naturally occurring heterogeneous tumours, which have the characteristics of sporadic human malignancies and therefore are more suitable for detailed oncological study than most xenograft or genetically modified rodent models. Furthermore, the canine genome has been comprehensively analysed and sequenced to a 7.6-fold coverage, and a very accurate version of this sequencing is available for study. The purpose of this manuscript is to present a comprehensive review of published data related to colorectal cancer in dogs. In addition, data regarding interspecies comparison of molecular events driving canine and human intestinal carcinogenesis is presented.

Tensor Decomposition of Largest Convolutional Eigenvalues Reveals Pathologic Predictive Power of RhoB in Rectal Cancer Biopsy

RhoB protein belongs to the Rho GTPase family, which plays an important role in governing cell signaling and tissue morphology. RhoB expression is known to have implications in pathologic processes of diseases. Investigation in the regulation and communication of this protein, detected by immunohistochemical staining on the microscope, is worth exploring to gain insightful information that may lead to identifying optimal disease treatment options. In particular, the role of RhoB in rectal cancer is not well discovered. Here, we report that methods of deep learning-based image analysis and the decomposition of multiway arrays discover the predictive factor of RhoB in two cohorts of patients with rectal cancer having survival rates of <5 and >5 years. The analysis results show distinctions between the tensor decomposition factors of the two cohorts.

Clinical significance of the histopathological metastatic largest lymph node size in colorectal cancer patients

Background

The metastatic lymph nodes (MLN) are interpreted to be correlated with prognosis of the colorectal cancers (CRC). The present retrospective study aimed to investigate the clinical significance of the largest MLN size in terms of postoperative outcomes and its predictive value in the prognosis of the patients with stage III CRC.

Methods

Between May 2013 and December 2018, a total of 101 patients who underwent curative resection for stage III CRC retrospectively reviewed. All patients were divided into two groups regarding cut-off value (<1.05 cm and ≥1.05 cm) of maximum MLN diameter measured histopathologically. A comparative analysis of demographic and clinicopathological characteristics of the patients and their postoperative outcomes were performed.

Results

Two groups carried similar demographic data and preoperative laboratory variables except the lymphocyte count, hematocrit (HCT) ratio, hemoglobin level and mean corpuscular volume (MCV) value (p<0.05). The patients with MLN diameter ≥1.05 cm (n=46) needed more erythrocyte suspension and were hospitalized longer than the patients with a diameter <1.05 cm (n=55) (p=0.006 and 0.0294, respectively). Patients with MLN diameter < 1.05 cm had a significantly longer overall survival than patients with MLN diameter ≥ 1.05 cm (75,29 vs. 52,57 months, respectively). Regarding the histopathologic features, the patients with MLN diameter ≥1.05 cm had larger tumor size and higher number of MLN than those with diameter <1.05 cm (p=0.049 and 0.001).

Conclusion

The size of MLN larger than 1.05 cm may be predictive for a poor prognosis and lower survival of stage III CRC patients. The largest MLN size may be a proper alternative factor to the number of MLNs in predicting prognosis or in staging CRC patients.

Prognostic value of elastic lamina staining in patients with stage III colon cancer

OBJECTIVE

The objectives of this study were to analyze the difference between the preoperative radiological and postoperative pathological stages of colorectal cancer (CRC) and explore the feasibility of elastic lamina invasion (ELI) as a prognostic marker for patients with stage III colon cancer.

METHODS

A total of 105 consecutive patients underwent radical surgery (R0 resection) for stage III colon cancer at the Cancer Hospital of China Medical University between January 2015 and December 2017. Clinicopathological features, including radiological stage and elastic lamina staining, were analyzed for prognostic significance in stage III colon cancer.

RESULTS

A total of 105 patients with stage III colon cancer who met the criteria and had complete data available were included. The median follow-up period of survivors was 41 months. During the follow-up period, 33 (31.4%) patients experienced recurrence after radical resection, and the 3-year disease-free survival (DFS) rate was 64.8%. The consistency between preoperative radiological and postoperative pathological staging was poor (κ = 0.232, P < 0.001). The accuracy of ≤ T2 stage diagnoses was 97.1% (102/105), that of T3 stage was 60.9% (64/105), that of T4a stage was 68.6% (72/105) and that of T4b stage was 91.4% (96/105). The DFS rate of T3 ELI (+) patients was significantly lower than that of both T3 ELI (-) patients (P = 0.000) and pT4a patients (P = 0.013). The DFS rate of T3 ELI (-) patients was significantly higher than that of pT4b patients (P=0.018). T3 ELI (+) (HR (Hazard ratio), 8.444 [95% CI, 1.736-41.067]; P = 0.008), T4b (HR, 57.727[95% CI, 5.547-600.754]; P = 0.001), N2 stage (HR, 10.629 [95% CI, 3.858-29.286]; P < 0.001), stage III (HR, 0.136 [95% CI, 0.31-0.589]; P = 0.008) and perineural invasion (PNI) (HR, 8.393 [95% CI, 2.094-33.637]; P = 0.003) were independent risk factors for postoperative recurrence of stage III colon cancer.

CONCLUSIONS

The consistency between preoperative radiological and postoperative pathological staging was poor, especially for tumors located in the ascending colon and descending colon. Elastic lamina staining is expected to become a stratified indicator of recurrence risk for patients with stage III colon cancer and a guide for individualized adjuvant chemotherapy, thus improving patient prognosis.

Building a knowledge base for colorectal cancer patient care using formal concept analysis

Background

Colorectal cancer (CRC) is a heterogeneous disease with different responses to targeted therapies due to various factors, and the treatment effect differs significantly between individuals. Personalize medical treatment (PMT) is a method that takes individual patient characteristics into consideration, making it the most effective way to deal with this issue. Patient similarity and clustering analysis is an important aspect of PMT. This paper describes how to build a knowledge base using formal concept analysis (FCA), which clusters patients based on their similarity and preserves the relations between clusters in hierarchical structural form.

Methods

Prognostic factors (attributes) of 2442 CRC patients, including patient age, cancer cell differentiation, lymphatic invasion and metastasis stages were used to build a formal context in FCA. A concept was defined as a set of patients with their shared attributes. The formal context was formed based on the similarity scores between each concept identified from the dataset, which can be used as a knowledge base.

Results

A hierarchical knowledge base was constructed along with the clinical records of the diagnosed CRC patients. For each new patient, a similarity score to each existing concept in the knowledge base can be retrieved with different similarity calculations. The ranked similarity scores that are associated with the concepts can offer references for treatment plans.

Conclusions

Patients that share the same concept indicates the potential similar effect from same clinical procedures or treatments. In conjunction with a clinician’s ability to undergo flexible analyses and apply appropriate judgement, the knowledge base allows faster and more effective decisions to be made for patient treatment and care.

Efficacy of a Traction Device for Endoscopic Submucosal Dissection Using a Scissor-Type Knife: A Randomized Controlled Trial

INTRODUCTION

Although safe, colorectal endoscopic submucosal dissection (ESD) using a scissor-type knife has a slow resection speed. We aimed to evaluate the efficacy of a traction device to hasten the resection speed.

METHODS

This multicenter randomized controlled trial was conducted at 3 Japanese institutions. Patients with a 20-50-mm superficial colorectal tumor were enrolled and randomly assigned to a conventional-ESD (C-ESD) group or a traction-assisted ESD (T-ESD) group. The primary outcome was the resection speed.

RESULTS

The C-ESD and T-ESD groups comprised 49 and 48 patients, respectively. Although the mean resection speed was not significantly different in the entire cohort between the groups (23.7 vs 25.6 mm 2 /min, respectively; P = 0.43), it was significantly faster with T-ESD than with C-ESD at the cecum (32.4 vs 16.7 mm 2 /min, respectively; P = 0.02). The mean resection speed of tumors ≥30 mm tended to be faster by T-ESD than by C-ESD (34.6 vs 27.8 mm 2 /min, respectively; P = 0.054). The mean procedure time of T-ESD was significantly shorter than that of C-ESD (47.3 vs 62.3 minutes, respectively; P = 0.03). The en bloc (100% vs 100%), complete (98.0% vs 97.9%), and curative resection (93.9% vs 91.7%) rates were similar between the 2 groups. Perforation and delayed hemorrhage occurred in only 1 patient each in the T-ESD group.

DISCUSSION

Although the resection rates were sufficiently high and adverse event rates were extremely low in both the groups, the use of a traction device for ESD in the proximal colon and for large lesions may increase the resection speed.

Utility of dual-layer spectral-detector CT imaging for predicting pathological tumor stages and histologic grades of colorectal adenocarcinoma

Objectives

To assess the utility of Dual-layer spectral-detector CT (DLCT) in predicting the pT stage and histologic grade for colorectal adenocarcinoma (CRAC).

Methods

A total of 131 patients (mean 62.7 ± 12.9 years; 72 female, 59 male) with pathologically confirmed CRAC (35 pT1-2, 61 pT3, and 35 pT4; 32 high grade and 99 low grade), who received dual-phase DLCT were enrolled in this retrospective study. Normalized iodine concentration (NIC), slope of the spectral HU curve (λHU), and effective atomic number (Eff-Z) were measured for each lesion by two radiologists independently. Intraobserver reliability and interobserver agreement were assessed. The above values were compared between three pT-stage and two histologic-grade groups. The correlation between the pT stages and above values were assessed. Receiver operating characteristic (ROC) curves were calculated to evaluate the diagnostic efficacy.

Results

Intra-class correlation coefficients were ranged from 0.856 to 0.983 for all measurements. Eff-Z [7.21(0.09) vs 7.31 (0.10) vs 7.35 (0.19)], NIC_AP [0.11 (0.05) vs 0.15 (0.08) vs 0.15 (0.08)], NIC_VP [0.27 (0.06) vs 0.34 (0.11) vs 0.35 (0.12)], λHU_AP [1.20 (0.45) vs 1.93 (1.18) vs 2.37 (0.91)], and λHU_VP [2.07 (0.68) vs 2.35 (0.62) vs 3.09 (1.07)] were significantly different among pT stage groups (all P<0.001) and exhibited a positive correlation with pT stages (r= 0.503, 0.455, 0.394, 0.512, 0.376, respectively, all P<0.001). Eff-Z [7.37 (0.10) vs 7.28 (0.08)], NIC_AP[0.20 (0.10) vs 0.13 (0.08)], NIC_VP[0.35 (0.07) vs 0.31 (0.11)], and λHU_AP [2.59 (1.11) vs 1.63 (0.75)] in the high-grade group were markedly higher than those in the low-grade group (all P<0.05). For discriminating the advanced- from early-stage CARC, the AUCs of Eff-Z, NIC_AP, NIC_VP, λHU_AP, and λHU_VP were 0.83, 0.80, 0.79, 0.86, and 0.68, respectively (all P<0.001). For discriminating the high- from low-grade CARC, the AUCs of Eff-Z, NIC_AP, NIC_VP, and λHU_AP were 0.81, 0.81, 0.64, and 0.81, respectively (all P<0.05).

Conclusions

The quantitative parameters derived from DLCT may provide new markers for assessing pT stages and histologic differentiation in patients with CRAC.

Establishment and validation of a postoperative predictive model for patients with colorectal mucinous adenocarcinoma

BACKGROUND

The aim of this study was to develop comprehensive and effective nomograms for predicting overall survival (OS) and cancer-specific survival (CSS) rates in patients with colorectal mucinous adenocarcinoma (CRMA).

METHODS

A total of 4711 CRMA patients who underwent radical surgery between 2010 and 2018 from the Surveillance, Epidemiology, and End Results (SEER) database were collected and randomized into development (n=3299) and validation (n=1412) cohorts at a ratio of 7:3 for model development and validation. OS and CSS nomograms were developed using the prognostic factors from the development cohort after multivariable Cox regression analysis. The performance of the nomograms was evaluated using Harrell's concordance index (C-index), calibration diagrams, receiver operating characteristic (ROC) curves, and decision curve analysis (DCA).

RESULTS

The study included 4711 patients. Multivariate Cox regression analysis demonstrated that age, tumor size, grade, pT stage, pN stage, M stage, carcinoembryonic antigen, perineural invasion, tumor deposits, regional nodes examined, and chemotherapy were correlated with OS and CSS. Marital status was independently related to OS. In the development and validation cohorts, the C-index of OS was 0.766 and 0.744, respectively, and the C-index of CSS was 0.826 and 0.809, respectively. Calibration curves and ROC curves showed predictive accuracy. DCA showed that the nomograms had excellent potency over the 8th edition of the TNM staging system with higher clinical net benefits. Significant differences in OS and CSS were observed among low-, medium-, and high-risk groups.

CONCLUSIONS

Nomograms were developed for the first time to predict personalized 1-, 3-, and 5-year OS and CSS in CRMA postoperative patients. External and internal validation confirmed the excellent discrimination and calibration ability of the nomograms. The nomograms can help clinicians design personalized treatment strategies and assist with clinical decisions.

Construction and Validation of Pyroptosis-Related lncRNA Prediction Model for Colon Adenocarcinoma and Immune Infiltration Analysis

Objective

Colon adenocarcinoma (COAD) is one of the most prevalent cancers worldwide. However, the pyroptosis-related lncRNAs of COAD have not been deeply examined and validated. Here, we constructed and validated a risk model on pyroptosis-related lncRNAs in COAD.

Methods

The RNA sequencing transcriptome and clinical data of COAD patients were downloaded from The Cancer Genome Atlas (TCGA) database. Differentially expressed pyroptosis-related mRNAs and mRNA-lncRNA coexpression network were identified. After univariate and multifactorial cox analyses of prognosis-related lncRNAs, a risk model was constructed. Next, we analyzed the differences in immune infiltration, immune checkpoint blockade-, immune checkpoint-, and N6-methyladenosine-related gene expressions between the high- and low-risk groups. RT-qPCR was used to validate the expression of lncRNAs.

Result

A risk model was constructed based on 9 pyroptosis-related lncRNAs and separated COAD patients into the high- and low-risk groups. Immune infiltration analysis and immune checkpoint blockade-, immune checkpoint-, and N6-methyladenosine-related genes showed significant differences between the two subgroups. RT-qPCR showed that the 9 pyroptosis-related lncRNAs could be used as prognostic indicators.

Conclusion

A novel risk model based on pyroptosis-related lncRNAs was constructed and demonstrated that these lncRNAs might be used as independent prognostic biomarkers. This will also assist shed light on the COAD prognosis and therapy.

Abnormality of Apico-Basal Polarity in Adenocarcinoma

Apico–basal polarity is a fundamental property of the epithelium that functions as a barrier, holds cells together, and determines the directions of absorption and secretion. Apico–basal polarity is regulated by extracellular matrix‐integrin binding and downstream signaling pathways, including focal adhesion kinase, rouse‐sarcoma oncogene (SRC), and RHO/RHO‐associated kinase (ROCK). Loss of epithelial cell polarity plays a critical role in the progression of cancer cells. However, in differentiated carcinomas, polarity is not completely lost but dysregulated. Recent progress with a three‐dimensional culture of primary cancer cells allowed for studies of the mechanism underlying the abnormality of polarity in differentiated cancers, including flexible switching of polarity status in response to the microenvironment. Invasive micropapillary carcinoma (MPC) is one of the histopathological phenotypes of adenocarcinoma, which is characterized by inverted polarity. Aberrant activation of RHO–ROCK signaling plays a critical role in the MPC phenotype. Establishing in vitro models will contribute to future drug targeting of the abnormal polarity status in cancer.

Roles of Keratins in Intestine

Keratins make up a major portion of epithelial intermediate filament proteins. The widely diverse keratins are found in both the small and large intestines. The human intestine mainly expresses keratins 8, 18, 19, and 20. Many of the common roles of keratins are for the integrity and stability of the epithelial cells. The keratins also protect the cells and tissue from stress and are biomarkers for some diseases in the organs. Although an increasing number of studies have been performed regarding keratins, the roles of keratin in the intestine have not yet been fully understood. This review focuses on discussing the roles of keratins in the intestine. Diverse studies utilizing mouse models and samples from patients with intestinal diseases in the search for the association of keratin in intestinal diseases have been summarized.

Decorating Bacteria with Triple Immune Nanoactivators Generates Tumor-Resident Living Immunotherapeutics

An approach of decorating bacteria with triple immune nanoactivators is reported to develop tumor-resident living immunotherapeutics. Under cytocompatible conditions, tumor-specific antigens and checkpoint blocking antibodies are simultaneously conjugated onto bacterial surface and then polydopamine nanoparticles are formed via in situ dopamine polymerization. In addition to serving as a linker, polydopamine with its photothermal effect can repolarize tumor-associated macrophages to a pro-inflammatory phenotype. The linked antigens promote the maturation of dendritic cells and generate tumor-specific immune responses, while the anchored antibodies block immune checkpoints and activate cytotoxic T lymphocytes. Decorated bacteria show spatiotemporal tumor retention and proliferation-dependent drug release, achieving potent antitumor effects in two antigen-overexpressing tumor models. This work provides a versatile platform to prepare multimodal and long-acting therapeutics for cancer immunotherapy.

Efficacy and safety comparison of scissor-type knives with needle-type knives for colorectal endoscopic submucosal dissection: a post-hoc propensity score-matched analysis (with videos)

BACKGROUND AND AIMS

Many knives have been developed to improve the efficacy and safety of endoscopic submucosal dissection (ESD). We aimed to evaluate the efficacy and safety of scissor-type knives for colorectal ESD compared with needle-type knives.

METHODS

We performed a post-hoc propensity score-matched analysis in an 11-facility study between August 2013 and December 2018. A total of 2330 patients (2498 lesions) who underwent colorectal ESD were divided into needle-type (1923 patients, 2067 lesions) and scissor-type (407 patients, 431 lesions) knife groups. Short-term outcomes were compared between the 2 groups.

RESULTS

Two-to-one propensity score-matched analysis identified 814 (709 patients) and 407 (386 patients) lesions in the needle- and scissor-type knife groups, respectively. The median resection speed was significantly faster in the needle-type group (18.3 mm²/min) than in the scissor-type group (13.2 mm²/min, P < .0001), whereas en-bloc and histologic complete resection rates were not significantly different between the needle- and scissor-type groups (96.8% [788/814] vs 98.3% [400/407], P = .1888 and 95.1% [774/814] vs 95.6% [389/407], P = .7763, respectively). The rate of lesions resected using a single knife was significantly higher in the scissor-type group (98.5% [401/407]) than in the needle-type group (43.9% [357/814], P < .0001). Rates of intraoperative perforation and delayed bleeding were significantly lower in the scissor-type group than in the needle-type group (.7% [3/407] vs 2.5% [20/814], P = .0431 for each).

CONCLUSIONS

Scissor-type knives are safer for colorectal ESD. However, they are associated with slower resection speeds compared with needle-type knives. (Clinical trial registration number: UMIN000016197.).

Three-dimensional imaging of intramural perineural invasion in colorectal cancer: Three-dimensional reconstruction approach with multiple immunohistochemically stained sections

Perineural invasion (PNI) at Auerbach's plexus in colorectal cancer (CRC), known as intramural PNI, is associated with adverse prognostic outcomes. This study aimed to characterize the three-dimensional (3D) architecture of CRC with intramural PNI and to evaluate the morphological features of tumor invasion around nerve tissue. Serial tissue sections from two cases of CRC were stained with cytokeratin AE1/AE3 and an anti-S-100 protein antibody. 3D models were reconstructed by scanning the virtual slides. In one case, intramural PNI was observed at the horizontal invasive front. The 3D reconstruction model showed tumor cells that appeared to infiltrate along the nervous meshwork, the structure of which was preserved. In the other case, intramural PNI was observed both at and behind the horizontal invasive front, and the 3D reconstruction model showed that the tumor cells appeared to be involved with nerve cells at the focal part of the horizontal invasive front. However, the nervous meshwork structure was not well identified in cancer-involved areas. This is the first study to characterize the 3D structure of tumor invasion around nerve tissue in CRC, demonstrating the morphological features of intramural PNI in CRC.

Application of Prognostic Models Based on Psoas Muscle Index, Stage, Pathological Grade, and Preoperative Carcinoembryonic Antigen Level in Stage II-III Colorectal Cancer Patients Undergoing Adjuvant Chemotherapy

OBJECTIVE

To investigate the effect of sarcopenia on the prognosis of stage II-III colorectal cancer patients undergoing adjuvant chemotherapy.

METHODS

A total of 196 stage II-III colorectal cancer patients who received 8 cycles of postoperative chemotherapy were retrospectively analyzed. An abdominal CT acquired at 3-4 weeks after surgery was used to calculate the psoas muscle index. Subsequently, once gender-specific receiver operating characteristic curves were plotted and cut-off values of psoas muscle index were defined, the clinicopathological characteristics and the prognosis of patients with high and low values were compared. Lastly, prognostic models were established based on the independent prognostic factors of relapse-free survival and overall survival identified by COX analysis.

RESULTS

Based on the psoas muscle index, the prevalence of sarcopenia was 37.5% among 196 patients. This prevalence has significant correlation with patients' age and gender. However, it was not related to the AJCC stage, T stage, lymph node metastasis, pathological grade, grade III-IV myelosuppression, or preoperative carcinoembryonic antigen level. In addition, both the relapse-free and the overall survival of patients with low and high psoas muscle indexes were significantly different. COX analysis indicated that the psoas muscle index was an independent prognostic factor. Both the overall survival prognostic model based on patients' psoas muscle index, stage, pathological grade, and preoperative carcinoembryonic antigen level and the relapse-free survival prognostic model based on patients' psoas muscle index, pathological grade, and preoperative carcinoembryonic antigen level could accurately predict the prognosis of patients.

CONCLUSION

For stage II-III colorectal cancer patients, the presence of sarcopenia before adjuvant chemotherapy would adversely affect their recurrence-free and overall survival. Prognostic models based on psoas muscle index, stage, pathological grade, and preoperative carcinoembryonic antigen level could accurately predict the prognosis in these patients.

Mucinous Adenocarcinoma Predicts Poor Response and Prognosis in Patients With Locally Advanced Rectal Cancer: A Pooled Analysis of Individual Participant Data From 3 Prospective Studies

PURPOSE

To evaluate the predictive implications and prognosis of mucinous adenocarcinoma (MAC) in locally advanced rectal cancer (LARC) with intensified neoadjuvant treatment.

METHODS

Individual patient data of LARC patients from 3 prospective clinical trials was analyzed. Neoadjuvant treatment regimens comprised chemoradiotherapy (CRT) with fluorouracil (5-FU) or mFOLFOX6, neoadjuvant chemotherapy alone with mFOLFOX6 or mFOLFOXIRI. The postoperative pathological result, local recurrence and disease-free survival (DFS) were retrospectively analyzed in patients with MAC and adenocarcinoma (AC) with neoadjuvant treatment.

RESULTS

Totally, 743 patients were recruited, with 620 patients eligible for analysis. Fifty-three (8.5%) patients were MAC. The pathological complete response (pCR) rate and tumor downstaging rate (ypStage 0-I) between MAC and AC patients was 7.5% vs. 22.0% (P = .01) and 20.8% vs. 48.7% (P < .001), respectively. Among patients receiving preoperative CRT with 5FU or mFOLFOX6, the pCR rate and tumor downstaging rate between MAC and AC patients was 11.1% vs. 27.3% (P = .03) and 23.7% vs. 52.6% (P = .001), respectively. Regarding neoadjuvant chemotherapy alone with mFOLFOX6 or mFOLFOXIRI, the pCR rate and tumor downstaging rate was 0 vs.13.2% (P = .11) and 11.8% vs. 42.5% (P = .03) between MAC and AC group, respectively. With the median follow-up time of 38.9 months, the 3-year DFS and 3-year locoregional recurrence rate was 58.4% vs. 77.6% (P = .02) and 26.0% vs. 5.7% (P = .001) in the MAC and AC group, respectively. MAC (hazard ratio [HR] 1.85, 95% confidence interval [CI], 1.15-2.98), PNI (HR 3.23, 95% CI, 1.85-5.72) and LVI (HR 2.04, 95% CI, 1.02-4.08) were independent prognosis factors and were associated with worse DFS.

CONCLUSIONS

Patients with MAC of the rectum are associated with a lower pCR rate and tumor downstaging rate, higher incidence of local recurrence, and poorer DFS with neoadjuvant treatment.

Establishing and Validating an Aging-Related Prognostic Four-Gene Signature in Colon Adenocarcinoma

Background

Aging is a process that biological changes accumulate with time and lead to increasing susceptibility to diseases like cancer. This study is aimed at establishing an aging-related prognostic signature in colon adenocarcinoma (COAD).

Methods

The transcriptome data and clinical variables of COAD patients were downloaded from TCGA database. The genes in GOBP_AGING gene set was used for prognostic evaluation by the univariate and multivariate Cox regression analyses. The model was presented by a nomogram and assessed by the Kaplan-Meier curves and calibration curves. The drug response and gene mutation were also performed to implicate the clinical significance. The GO and KEGG analyses were employed to unravel the potential functional mechanism.

Results

The Gene Set Enrichment Analysis result indicates that GOBP_AGING pathway is significantly enriched in COAD samples. Four aging-related genes are finally used to construct the aging-related prognostic signature: FOXM1, PTH1R, KL, and CGAS. The COAD patients with high risk score have much shorter overall survival in both train cohort and test cohort. The nomogram is then assembled to predict 1-year, 3-year, and 5-year survival. Patients with high risk score have elevated infiltrating B cell naïve and attenuated cisplatin sensitivity. The mutation landscape shows that the TTN, FAT4, ZFHX4, APC, and OBSCN gene mutation are different between high risk score patients and low risk score patients. The differentially expressed genes between patients with high score and low score are enriched in B cell receptor signaling pathway.

Conclusion

We constructed an aging-related signature in COAD patients, which can predict oncological outcome and optimize therapeutic strategy.

Determination of Additional Surgery after Non-Curative Endoscopic Submucosal Dissection in Patients with Early Gastric Cancer: A Practically Modified Application of the eCura System

Simple Summary

Recent treatment guidelines for gastric cancer recommended additional surgery for patients with non-curative endoscopic submucosal dissection (ESD). However, this strategy may be too excessive since few patients have lymph node metastasis (LNM). In this study, we modified the eCura system, a risk-scoring system for LNM after non-curative ESD, by classifying lymphatic invasion and venous invasion as a single entity of lymphovascular invasion. By using the modified eCura system, patients after non-curative ESD were simply categorized into high- and low-risk groups as lymph node metastasis depending on whether the tumor had lymphovascular invasion and other risk factors or not. Moreover, there was no intermediate-risk group, which could not recommend the appropriate treatment modality in the eCura system.

Abstract

Background: Additional surgery after non-curative endoscopic submucosal dissection (ESD) may be excessive as few patients have lymph node metastasis (LNM). It is necessary to develop a risk stratification system for LNM after non-curative ESD, such as the eCura system, which was introduced in the Japanese gastric cancer treatment guidelines. However, the eCura system requires venous and lymphatic invasion to be separately assessed, which is difficult to distinguish without special immunostaining. In this study, we practically modified the eCura system by classifying lymphatic and venous invasion as lymphovascular invasion (LVI). Method: We retrospectively reviewed 543 gastric cancer patients who underwent radical gastrectomy after non-curative ESD between 2006 and 2019. LNM was evaluated according to LVI as well as size >30 mm, submucosal invasion ≥500 µm, and vertical margin involvement, which were used in the eCura system. Results: LNM was present in 8.1% of patients; 3.6%, 2.3%, 7.4%, 18.3%, and 61.5% of patients with no, one, two, three, and four risk factors had LNM, respectively. The LNM rate in the patients with no risk factors (3.6%) was not significantly different from that in patients with one risk factor (2.3%, p = 0.523). Among patients with two risk factors, the LNM rate without LVI was significantly lower than with LVI (2.4% vs. 10.7%, p = 0.027). Among patients with three risk factors, the LNM rate without LVI was lower than with LVI (0% vs. 20.8%, p = 0.195), although not statistically significantly. Based on LNM rates according to risk factors, patients with LVI and other factors were assigned to the high-risk group (LNM, 17.4%) while other patients as a low-risk group (LNM, 2.4%). Conclusions: Modifying the eCura system by classifying lymphatic and venous invasion as LVI successfully stratified LNM risk after non-curative ESD. Moreover, the high-risk group can be simply identified based on LVI and the presence of other risk factors.

Outcomes of Non-metastatic Colon Cancer: A Single-Center Experience

Background

Colorectal cancer (CRC) is the most common gastrointestinal cancer. In the Saudi Cancer Registry, CRC ranked as the most common cancer in men and the third most common cancer in women. Data regarding the stage of CRC at presentation and patient demographics and outcomes in Saudi Arabia are lacking. This study aimed to investigate the prevalence, survival, and mortality rates of patients with non-metastatic CRC in a tertiary care hospital in Saudi Arabia. 

Methods

We conducted a retrospective chart review of patients diagnosed with adenocarcinoma of the colon or rectum at King Abdulaziz University Hospital between 2013 and 2017. Patients aged ≥18 years who presented with non-metastatic CRC and underwent curative resection were included. Patients with rectal cancer or metastatic colon cancer were excluded. Data on demographic characteristics, histopathological findings, tumor-node-metastasis stage, biomarkers, and surgical interventions were collected. Recurrence-free survival was defined as the time from surgery to the date of recurrence or death. All statistical analyses were performed using Stata/IC 15.1 (StataCorp, College Station, TX, USA).

Results

Among 260 patients diagnosed with CRC, 82 were included based on the inclusion/exclusion criteria. Among those patients, 65.9% were men and 47.5% were Saudi citizens. The mean age at the time of diagnosis was 60.8 years. Fifty-three patients (64.6%) had left-sided colon cancer. The mean tumor diameter was 52.6 mm. Most colon tumors were T3 lesions (71.3%), and 41% of patients did not have lymph node involvement (N0). Most patients (85.1%) underwent open surgery. In the multivariate analysis, only resection margin status and N stage (hazard ratio: 17.7 and 3.7, respectively) were identified as statistically significant factors affecting the recurrence-free survival. The one-, two-, and five-year recurrence-free rates were 80.5%, 66.5%, and 57.1%, respectively, and the one-, two-, and five-year and overall survival rates were 90.3%, 82.5%, and 82.5%, respectively.

Conclusions

We showed significant reductions in recurrence-free and overall survival within the first two years after surgical resection. Further prospective studies are needed to explore predictors.

Scatter patterns in lymph node metastases as a novel prognostic indicator in patients with stage III/N2 colorectal cancer

To classify patients with stage III/N2 colorectal cancer into high- and low-risk groups for recurrence, the present study compared clinicopathological features by immunohistochemical staining. The single-center analysis included 53/668 patients (7.9%) with stage III/N2 colorectal cancer who underwent radical resection between January 2006 and December 2014. The present study examined cancer cell distribution in metastatic lymph nodes and classified patients into a group with circumferential localization patterns like a cystic mass (CLP) and a group with scatter patterns like fireworks (SPF). Subsequently, 5-year relapse-free survival (5Y-RFS) and 5-year overall survival (5Y-OS) rates were compared and the histological type (differentiation degree) of the primary adenocarcinoma was included. The CLP group included 16 patients (30.2%) and the SPF group included 37 patients (69.8%). The 5Y-RFS rates in these groups were 75.0 vs. 37.8%, respectively (P=0.021), and the 5Y-OS rates were 81.3 vs. 48.6% (P=0.033). Patient clinicopathological characteristics exhibited no significant differences between groups. The adenocarcinoma was well differentiated in 14 patients (Well; 26.4%) and moderately (Mod; n=37) or poorly (Por; n=2) differentiated in 39 patients (Mod+Por; 73.6%). Patients were further classified into four groups: Well/CLP (n=6), Well/SPF (n=8), Mod+Por/CLP (n=10) and Mod+Por/SPF (n=29). For Well/CLP vs. Well/SPF, the 5Y-RFS rates were 66.7 vs. 25.0%, respectively (P=0.293), and for Mod+Por/CLP vs. Mod+Por/SPF (80.0 vs. 41.4%; P=0.052), the respective values for 5Y-OS were 66.7 vs. 50.0% (P=0.552) and 90.0 vs. 48.3% (P=0.059). Based on the aforementioned results, the CLP group was considered a low-risk group for recurrence with a relatively good prognosis; however, the SPF group was considered a high-risk group for recurrence with a poor prognosis, suggesting a need for more potent multi-combination chemotherapy in these patients from the early postoperative period.

Improving the management of early colorectal cancers (eCRC) by using quantitative markers to predict lymph node involvement and thus the need for major resection of pT1 cancers

BACKGROUND

Since implementing the NHS bowel cancer screening programme, the rate of early colorectal cancer (eCRC; pT1) has increased threefold to 17%, but how these lesions should be managed is currently unclear.

AIM

To improve risk stratification of eCRC by developing reproducible quantitative markers to build a multivariate model to predict lymph node metastasis (LNM).

METHODS

Our retrospective cohort of 207 symptomatic pT1 eCRC was assessed for quantitative markers. Associations between categorical data and LNM were performed using χ2 test and Fisher's exact test. Multivariable modelling was performed using logistic regression. Youden's rule gave the cut-point for LNM.

RESULTS

All significant parameters in the univariate analysis were included in a multivariate model; tumour stroma (95% CI 2.3 to 41.0; p=0.002), area of submucosal invasion (95% CI 2.1 to 284.6; p=0.011), poor tumour differentiation (95% CI 2.0 to 358.3; p=0.003) and lymphatic invasion (95% CI 1.3 to 192.6; p=0.028) were predictive of LNM. Youden's rule gave a cut-off of p>5%, capturing 18/19 LNM (94.7%) cases and leading to a resection recommendation for 34% of cases. The model that only included quantitative factors were also significant, capturing 17/19 LNM cases (90%) and leading to resection rate of 35% of cases (72/206).

CONCLUSIONS

In this study, we were able to reduce the potential resection rate of pT1 with the multivariate qualitative and/or quantitative model to 34% or 35% while detecting 95% or 90% of all LNM cases, respectively. While these findings need to be validated, this model could lead to a reduction of the major resection rate in eCRC.

Adequacy of Surgical Pathology Reports of Colorectal Carcinoma and Its Significance

Introduction Colorectal cancer is the fifth most common cancer in the world. For loco-regionally confined disease surgery is the definitive treatment. An adequate surgical pathology report is mandatory for the selection of adjuvant therapy. The objective of this study is to analyze whether adequate information is provided or not in the surgical pathology reports of colorectal carcinoma as according to College of American Pathologists (CAP) guidelines. Method This is a cross-sectional study carried out in the Department of Clinical Oncology, Jinnah Postgraduate Medical Center (JPMC) Karachi, tertiary care hospital in Pakistan. The duration of the study was from February 2020 to January 2021. A total of 153 surgical pathology reports issued by 11 different hospital-based laboratories after definitive surgery was assessed to look at its concordance rate with the checklist adapted from the CAP guidelines. Results Out of 153 surgical pathology reports, clinical information was provided in 72.5% of reports. Details of tumor extension were present in 88.2%, tumor margin in 75%, surgical procedure in 79%, and tumor deposits in 39.2% of reports. Macroscopic details including tumor perforation and evaluation of mesorectum were documented in 51.6% and 53.5% of the reports respectively. Details regarding perineural invasion along with lymphovascular invasion were present in 81.6% and 93% of the reports, respectively. The treatment effect was documented in only 25% of reports and regional lymph node status has been described in 85% of reports. Parameters described in all surgical pathology reports were: tumor site, tumor type, histologic type, and histologic grade. The pathological stage of the disease was documented in 91.5% of the reports. Conclusion This study concluded that surgical pathology reports of the majority of pathology laboratories were not fully adhered to the checklist provided by the CAP guidelines. This will affect post-operative management along with the prediction of disease prognosis.

KRAS phosphorylation regulates cell polarization and tumorigenic properties in colorectal cancer

Oncogenic mutations of KRAS are found in the most aggressive human tumors, including colorectal cancer. It has been suggested that oncogenic KRAS phosphorylation at Ser181 modulates its activity and favors cell transformation. Using nonphosphorylatable (S181A), phosphomimetic (S181D), and phospho-/dephosphorylatable (S181) oncogenic KRAS mutants, we analyzed the role of this phosphorylation to the maintenance of tumorigenic properties of colorectal cancer cells. Our data show that the presence of phospho-/dephosphorylatable oncogenic KRAS is required for preserving the epithelial organization of colorectal cancer cells in 3D cultures, and for supporting subcutaneous tumor growth in mice. Interestingly, gene expression differed according to the phosphorylation status of KRAS. In DLD-1 cells, CTNNA1 was only expressed in phospho-/dephosphorylatable oncogenic KRAS-expressing cells, correlating with cell polarization. Moreover, lack of oncogenic KRAS phosphorylation leads to changes in expression of genes related to cell invasion, such as SERPINE1, PRSS1,2,3, and NEO1, and expression of phosphomimetic oncogenic KRAS resulted in diminished expression of genes involved in enterocyte differentiation, such as HNF4G. Finally, the analysis, in a public data set of human colorectal cancer, of the gene expression signatures associated with phosphomimetic and nonphosphorylatable oncogenic KRAS suggests that this post-translational modification regulates tumor progression in patients.

The effect of mutation status, pathological features and tumor location on prognosis ın patients with colorectal cancer

OBJECTIVE

Colorectal cancer is the most common malignancy of the gastrointestinal tract. It is the third most common tumor in both genders and the second reason of cancer-related deaths. In recent years, tumor location has gained importance as a prognostic indicator. In this study, we aimed to analyze if there was a prognostic effect of tumor location, the pathological features, and the mutation status of patients on survival.

METHODS

Two-hundred and ten colorectal cancer patients aged 18 years and older were included into the study. One-hundred and forty-two patients had left-sided tumor and 68 patients had right-sided tumor. Patients who had other malignancies rather than squamous cell skin cancer and in situ cervical cancer were excluded. All statistical tests were carried out using two-sided process, and a p≤0.05 was considered statistically significant.

RESULTS

There were 140 men and 70 women in the study. The median age of the patients was 62 years old. There was no statistically significant difference according to tumor location and survival of patients. The overall survival of patients with right-sided tumors was 60.5 months and 47.2 months for left-sided tumors. Disease-free survival of patients was 63.7 months for right-sided tumors and 46 months for left-sided ones. Perineural invasion, grade and stage were crucial prognostic parameters. Disease-free survival was longer for female colorectal cancer patients.

CONCLUSION

According to our study, survival of patients was similar regardless of tumor location. This can be explained by the different sequencing of treatment strategies and divergent population genetics.