Rectal and colon cancer: Not just a different anatomic site

The impact of preoperative treatments on the immune environment of rectal cancer

To improve local disease control, the use of preoperative radiotherapy either alone or combined with chemotherapy has become standard practice in rectal cancer, but it is unclear how these treatments modify the antitumoral immune response. We aimed to evaluate tumor histopathologic features and the prognostic effect of host immune response in rectal cancer with variable treatment modalities. Ninety-five rectal cancers with short-course radiotherapy (SRT), 97 with long-course chemoradiotherapy (CRT), and 154 without preoperative treatments, were evaluated for histopathologic features including Crohn's-like reaction (CLR). CD3+ and CD8+ immunohistochemistry and tumor cells were analyzed from tumor tissue microarray samples to calculate T-cell densities and G-cross function values to estimate cancer cell-T-cell co-localization (proximity score). We found that lymphocyte densities were diminished after SRT, but CLR was scarcer after CRT. Proximity score and CLR density were prognostic for survival in cancer without preoperative treatments and could be combined into an enhanced prognostic score (immune grade). In the irradiated tumors, CLR density remained prognostic while the impact of T-cell infiltration was insufficient alone. In multivariable analysis, the immune grade proved to be an independent prognostic factor for survival. In conclusion, the immune contexture of rectal cancer harbors prognostic significance even after preoperative radiotherapy.

Circulating Bacterial DNA in Colorectal Cancer Patients: The Potential Role of Fusobacterium nucleatum

Intestinal dysbiosis is a major contributor to colorectal cancer (CRC) development, leading to bacterial translocation into the bloodstream. This study aimed to evaluate the presence of circulated bacterial DNA (cbDNA) in CRC patients (n = 75) and healthy individuals (n = 25). DNA extracted from peripheral blood was analyzed using PCR, with specific primers targeting 16S rRNA, Escherichia coli (E. coli), and Fusobacterium nucleatum (F. nucleatum). High 16S rRNA and E. coli detections were observed in all patients and controls. Only the detection of F. nucleatum was significantly higher in metastatic non-excised CRC, compared to controls (p < 0.001), non-metastatic excised CRC (p = 0.023), and metastatic excised CRC (p = 0.023). This effect was mainly attributed to the presence of the primary tumor (p = 0.006) but not the presence of distant metastases (p = 0.217). The association of cbDNA with other clinical parameters or co-morbidities was also evaluated, revealing a higher detection of E. coli in CRC patients with diabetes (p = 0.004). These results highlighted the importance of bacterial translocation in CRC patients and the potential role of F. nucleatum as an intratumoral oncomicrobe in CRC.

Vasorin (VASN) overexpression promotes pulmonary metastasis and resistance to adjuvant chemotherapy in patients with locally advanced rectal cancer

BACKGROUND

LARC patients commonly receive adjuvant therapy, however, hidden micrometastases still limit the improvement of OS. This study aims to investigate the impact of VASN in rectal cancer with pulmonary metastasis and understand the underlying molecular mechanisms to guide adjuvant chemotherapy selection.

METHODS

Sequencing data from rectal cancer patients with pulmonary metastasis from Sun Yat-sen University Cancer Center (SYSUCC) and publicly available data were meticulously analyzed. The functional role of VASN in pulmonary metastasis was validated in vivo and in vitro. Coimmunoprecipitation (co-IP), immunofluorescence, and rescue experiments were conducted to unravel potential molecular mechanisms of VASN. Moreover, VASN expression levels in tumor samples were examined and analyzed for their correlations with pulmonary metastasis status, tumor stage, adjuvant chemotherapy benefit, and survival outcome.

RESULTS

Our study revealed a significant association between high VASN expression and pulmonary metastasis in LARC patients. Experiments in vitro and in vivo demonstrated that VASN could promote the cell proliferation, metastasis, and drug resistance of colorectal cancer. Mechanistically, VASN interacts with the NOTCH1 protein, leading to concurrent activation of the NOTCH and MAPK pathways. Clinically, pulmonary metastasis and advanced tumor stage were observed in 90% of VASN-positive patients and 53.5% of VASN-high patients, respectively, and VASN-high patients had a lower five-year survival rate than VASN-low patients (26.7% vs. 83.7%). Moreover, the Cox analysis and OS analysis indicated that VASN was an independent prognostic factor for OS (HR = 7.4, P value < 0.001) and a predictor of adjuvant therapy efficacy in rectal cancer.

CONCLUSIONS

Our study highlights the role of VASN in decreasing drug sensitivity and activating the NOTCH and MAPK pathways, which leads to tumorigenesis and pulmonary metastasis. Both experimental and clinical data support that rectal cancer patients with VASN overexpression detected in biopsies have a higher risk of pulmonary metastasis and adjuvant chemotherapy resistance.

The survival outcome differs between left-sided colon cancer and middle/low rectal cancer after colorectal hepatic metastasectomy

BACKGROUND

The clinical outcomes between left-sided colon cancer and middle/low rectal cancer seem to be different. This study aimed to examine the effect of primary tumor location regarding the left-sided colon and middle/low rectum on the overall survival (OS) of patients who underwent colorectal hepatic metastasectomy.

METHODS

Patients who underwent colorectal hepatic metastasectomy were retrospectively enrolled. Patients were classified into 2 groups according to the primary tumor location (left-sided colon and middle/low rectum). Categorical variables were compared using the chi-square test or Fisher exact test, and continuous variables were analyzed using the Student t test. Survival was analyzed using the Kaplan-Meier method and log-rank test. The prognostic factors were analyzed by univariate and multivariate analyses using Cox proportional hazards regression models.

RESULTS

Overall, 365 patients were enrolled. Patients with left-sided colon cancer had significantly better OS than those with middle/low rectal cancer (hazard ratio [HR], 0.725; P = .018), with median OS estimates of 48 and 38 months, respectively. In the subgroup analysis of RAS mutations, patients with left-sided colon cancer had significantly prolonged OS compared with those with middle/low rectum cancer (HR, 0.608; P = .034), with median OS estimates of 49 and 26 months, respectively. This observation was limited to patients with RAS mutations.

CONCLUSION

According to our findings, patients with middle/low rectal cancer had poorer survival outcome and should not be categorized together with patients with left-sided colon cancer in terms of OS after colorectal hepatic metastasectomy.

Expression and Prognosis of Differential Gene Troponin T1 Between Right and Left Colon Cancers

Colorectal cancer (CRC) is one of the most common digestive tract tumors in humans. At present, many scholars believe that the primary site of the tumor has a direct and profound impact on its curative effect. There are significant differences in the expression of many genes, tumor microenvironment, and prognosis between the left and right colon. However, there is a lack of detailed studies on whether the differentially expressed genes in the left and right colon significantly impact the prognosis of patients with CRC. Troponin T1 ( TNNT1 ) is an important gene that affects the prognosis difference between left and right colon cancer screening from "The Cancer Genome Atlas" database. By analyzing the differential gene expression data and clinical data of the left and right hemicolons in the database, the online prognostic database was used to screen the key molecules that significantly affect the tumor immune microenvironment and patient prognosis and to predict their functions and pathways. Quantitative reverse transcription-polymerase chain reaction was used to verify the expression difference of TNNT1 in CRC cell lines SW480 and HCT116, and normal human colorectal epithelial cell line FHC. The relationship between TNNT1 expression in 88 pairs of CRC samples and clinical information and pathologic parameters of patients with CRC was analyzed to judge the impact of TNNT1 expression on patient survival. Database analysis showed that TNNT1 was significantly overexpressed in CRC, and TNNT1 was one of the main differential genes between left colon cancer (LCC) and right colon cancer (RCC). The expression of TNNT1 was significantly increased in RCC, which could lead to poor prognosis of patients. Quantitative reverse transcription-polymerase chain reaction indicated that the expression of TNNT1 was significantly up-regulated in CRC cell lines SW480 and HCT116. Eighty-eight immunohistochemistry (IHC) of CRC tissues and adjacent tissues suggested that the expression of TNNT1 in CRC was significantly higher than that in normal adjacent tissues. By analyzing the clinical information and pathologic indicators matched with these clinical samples, we found that high TNNT1 expression in the primary tumor location (right colon) and high N stage (N2, N3) were unfavorable factors affecting the prognosis of patients with CRC. Multivariate Cox regression analysis suggested that high expression of TNNT1 may be an independent risk factor for the prognosis of patients with CRC. As one of the main differential genes between LCC and RCC, TNNT1 is representative to some extent. Its high expression may be one of the reasons why the prognosis of patients with RCC is worse than that of patients with LCC.

The incidence rate of allergic reactions induced by oxaliplatin is higher in patients with rectal cancer compared with colon cancer

AIM

To explore the diverse profiles of adverse reactions caused by oxaliplatin between colon and rectal cancer, we investigated the toxicity of oxaliplatin in patients with colon and rectal cancer.

METHODS

From January 2017 to December 2021, 200 cases of sporadic CRC patients with adverse reactions after oxaliplatin were collected from Harbin Medical University Cancer Hospital, Harbin, China. All patients received a chemotherapy regimen containing oxaliplatin (100 colon cancer and 100 rectal cancer). We reviewed the adverse reactions induced by oxaliplatin in patients with colon and rectal cancer.

RESULTS

We found there was no significant difference in gastrointestinal toxicity, hematotoxicity, neurotoxicity, hepatotoxicity, respiratory toxicity, and cardiotoxicity caused by oxaliplatin between patients with colon cancer and patients with rectal cancer, but patients with rectal cancer were more prone to allergic reactions than patients with colon cancer after oxaliplatin. In addition, we found neutrophil-to-lymphocyte ratios (NLR) and platelet-to-lymphocyte ratios (PLR) were higher in patients with colon cancer than in patients with rectal cancer. This may reflect differences in immune status and inflammatory responses between colon cancer and rectal cancer, which might be the reason for more allergic reactions caused by oxaliplatin in colon cancer patients compared to rectal cancer patients.

CONCLUSION

Except for a higher incidence of allergic reactions in patients with rectal cancer, no significant difference in the incidence of adverse drug reactions associated with oxaliplatin was noted between patients with colon cancer and rectal cancer. Our results suggested more attention should be paid to the allergic reaction caused by oxaliplatin in patients with colon cancer.

Point/Counterpoint #2: Current Clinical Considerations With Nonoperative Management of Rectal Cancer

ABSTRACT

Locally advanced rectal cancer has historically been treated with multimodal therapy consisting of radiation therapy, chemotherapy, and total mesorectal excision. However, recent prospective trials and registry studies have demonstrated similar disease outcomes with nonoperative management for patients who experience an excellent clinical response to radiation and chemotherapy. This article reviews data regarding nonoperative management for rectal cancer, and highlights current challenges and limitations in a point-counterpoint format, in the context of two clinical cases.

NFκB signalling in colorectal cancer: Examining the central dogma of IKKα and IKKβ signalling

The NFκB pathway, known as the central regulator of inflammation, has a well-established role in colorectal cancer (CRC) initiation, progression, and therapy resistance. Due to the pathway's overarching roles in CRC, there have been efforts to characterise NFκB family members and target the pathway for therapeutic intervention. Initial research illustrated that the canonical NFκB pathway, driven by central kinase IKKβ, was a promising target for drug intervention. However, dose limiting toxicities and specificity concerns have resulted in failure of IKKβ inhibitors in clinical trials. The field has turned to look at targeting the less dominant kinase, IKKα, which along with NFκB inducing kinase (NIK), drives the lesser researched non-canonical NFκB pathway. However prognostic studies of the non-canonical pathway have produced conflicting results. There is emerging evidence that IKKα is involved in other signalling pathways, which lie outside of canonical and non-canonical NFκB signalling. Evidence suggests that some of these alternative pathways involve a truncated form of IKKα, and this may drive poor cancer-specific survival in CRC. This review aims to explore the multiple components of NFκB signalling, highlighting that NIK may be the central kinase for non-canonical NFκB signalling, and that IKKα is involved in novel pathways which promote CRC.

Incidence, Characteristics and Survival Rates of Bladder Cancer after Rectosigmoid Cancer Radiation

BACKGROUND

Historical external beam radiation therapy (EBRT) for rectosigmoid cancer (RCa) predisposed patients to an increased risk of secondary bladder cancer (BCa). However, no contemporary radiotherapy studies are available. We addressed this knowledge gap.

MATERIALS AND METHODS

Within the Surveillance, Epidemiology, and End Results database (2000-2020), we identified non-metastatic RCa patients who either underwent radiotherapy (EBRT+) or did not (EBRT-). Cumulative incidence plots and multivariable competing risk regression models (CRR) were fitted to address rates of BCa after RCa. In the subgroup of BCa patients, the same methodology addressed BCa-specific mortality (BCSM) according to EBRT exposure status.

RESULTS

Of the 188,658 non-metastatic RCa patients, 54,562 (29%) were EBRT+ vs. 134,096 (73%) who were EBRT-. In the cumulative incidence plots, the ten-year BCa rates were 0.7% in EBRT+ vs. 0.7% in EBRT- patients (p = 0.8). In the CRR, EBRT+ status was unrelated to BCa rates (multivariable HR: 1.1, p = 0.8). In the subgroup of 1416 patients with BCa after RCa, 443 (31%) were EBRT+ vs. 973 (69%) who were EBRT-. In the cumulative incidence plots, the ten-year BCSM rates were 10.6% in EBRT+ vs. 12.1% in EBRT- patients (p = 0.7). In the CRR, EBRT+ status was unrelated to subsequent BCSM rates (multivariable HR: 0.9, p = 0.9).

CONCLUSION

Although historical EBRT for RCa predisposed patients to higher BCa rates, contemporary EBRT for RCa is not associated with increased subsequent BCa risk. Moreover, in patients with BCa after RCa, exposure to EBRT does not affect BCSM.

Procyanidin C1 inhibits tumor growth and metastasis in colon cancer via modulating miR-501-3p/HIGD1A axis

INTRODUCTION

Although colon (COAD) and rectal adenocarcinoma (READ) combined to refer to colorectal cancer (CRC), substantial clinical evidence urged that CRC should be treated as two different cancers due to compared with READ, COAD showed higher morbidity and worse 5-year survival.

OBJECTIVES

This study has tried to screen for the crucial gene that caused the worse prognosis and investigate its mechanism for mediating tumor growth and metastases in COAD. Meanwhile, the potential anti-COAD compound implicated in this mechanism was identified and testified from 1,855 food-borne chemical kits. This study aims to bring a new perspective to the development of new anti-COAD drugs and personalized medicine for patients with COAD.

METHODS AND RESULTS

The survival-related hub genes in COAD and READ were screened out from The Cancer Genome Atlas (TCGA) database and the results showed that HIGD1A, lower expressed in COAD than in READ, was associated with poor prognosis in COAD patients, but not in READ. Over-expressed HIGD1A suppressed CRC cell proliferation, invasion, and migration in vitro and in vivo. Meanwhile, the different expressed microRNA profiles between COAD and READ showed that miR-501-3p was highly expressed in COAD and inhibited HIGD1A expression by targeting 3'UTR of HIGD1A. MiR-501-3p mimics promoted cell proliferation and metastasis in CRC cells. In addition, Procyanidin C1 (PCC1), a kind of natural polyphenol has been verified as a potential miR-501-3p inhibitor. In vitro and in vivo, PCC1 promoted HIGD1A expression by suppressing miR-501-3p and resulted in inhibited tumor growth and metastasis.

CONCLUSION

The present study verified that miR-501-3p/HIGD1A axis mediated tumor growth and metastasis in COAD. PCC1, a flavonoid that riched in food exerts anti-COAD effects by inhibiting miR-501-3p and results in the latter losing the ability to suppress HIGD1A expression. Subsequently, unfettered HIGD1A inhibited tumor growth and metastasis in COAD.

Progress of MRI in predicting the circumferential resection margin of rectal cancer: A narrative review

Rectal cancer (RC) is the third most frequently diagnosed cancer worldwide, and the status of its circumferential resection margin (CRM) is of paramount significance for treatment strategies and prognosis. CRM involvement is defined as tumor touching or within 1 mm from the outermost part of tumor or outer border of the mesorectal or lymph node deposits to the resection margin. The incidence of involved CRM varied from 5.4 % to 36 %, which may associate with an in consistent definition of CRM, the quality of surgeries, and the different examination modalities. Although T and N status are essential factors in determining whether a patient should receive neoadjuvant therapy before surgery, CRM status is a powerful predictor of local and distant recurrence as well as survival rate. This review explores the significance of CRM, the various assessment methods, and the role of magnetic resonance imaging (MRI) and artificial intelligence-based MRI in predicting CRM status. MRI showed potential advantage in predicting CRM status with a high sensitivity and specificity compared to computed tomography (CT). We also discuss MRI advancements in RC imaging, including conventional MRI with body coil, high-resolution MRI with phased-array coil, and endorectal MRI. Along with a discussion of artificial intelligence-based MRI techniques to predict the CRM status of RCs before and after treatments.

Identification of unique rectal cancer-specific subtypes

BACKGROUND

Existing colorectal cancer subtyping methods were generated without much consideration of potential differences in expression profiles between colon and rectal tissues. Moreover, locally advanced rectal cancers at resection often have received neoadjuvant chemoradiotherapy which likely has a significant impact on gene expression.

METHODS

We collected mRNA expression profiles for rectal and colon cancer samples (n = 2121). We observed that (i) Consensus Molecular Subtyping (CMS) had a different prognosis in treatment-naïve rectal vs. colon cancers, and (ii) that neoadjuvant chemoradiotherapy exposure produced a strong shift in CMS subtypes in rectal cancers. We therefore clustered 182 untreated rectal cancers to find rectal cancer-specific subtypes (RSSs).

RESULTS

We identified three robust subtypes. We observed that RSS1 had better, and RSS2 had worse disease-free survival. RSS1 showed high expression of MYC target genes and low activity of angiogenesis genes. RSS2 exhibited low regulatory T cell abundance, strong EMT and angiogenesis signalling, and high activation of TGF-β, NF-κB, and TNF-α signalling. RSS3 was characterised by the deactivation of EGFR, MAPK and WNT pathways.

CONCLUSIONS

We conclude that RSS subtyping allows for more accurate prognosis predictions in rectal cancers than CMS subtyping and provides new insight into targetable disease pathways within these subtypes.

Valuing the health benefits of nature-based recreational physical activity in England

Physical activity (PA) reduces the risk of several non-communicable diseases (NCDs). Natural environments support recreational PA. Using data including a representative cross-sectional survey of the English population, we estimated the annual value of nature-based PA conducted in England in 2019 in terms of avoided healthcare and societal costs of disease. Population-representative data from the Monitor of Engagement with the Natural Environment (MENE) survey (n = 47,580; representing 44,386,756) were used to estimate the weekly volume of nature-based recreational PA by adults in England in 2019. We used epidemiological dose-response data to calculate incident cases of six NCDs (ischaemic heart disease (IHD), ischaemic stroke (IS), type 2 diabetes (T2D), colon cancer (CC), breast cancer (BC) and major depressive disorder (MDD)) prevented through nature-based PA, and estimated associated savings using published costs of healthcare, informal care and productivity losses. We investigated additional savings resulting from hypothetical increases in: (a) visitor PA and (b) visitor numbers. In 2019, 22million adults > 16 years of age in England visited natural environments at least weekly. At reported volumes of nature-based PA, we estimated that 550 cases of IHD, 168 cases of IS, 1,410 cases of T2D, 41 cases of CC, 37 cases of BC and 10,552 cases of MDD were prevented, creating annual savings of £108.7million (95 % uncertainty interval: £70.3million; £150.3million). Nature-based recreational PA in England results in reduced burden of disease and considerable annual savings through prevention of priority NCDs. Strategies that increase nature-based PA could lead to further reductions in the societal burden of NCDs.

Influence of skeletal muscle and intermuscular fat on postoperative complications and long-term survival in rectal cancer patients

BACKGROUND

The body composition of patients with rectal cancer potentially affects postoperative outcomes. This study explored the correlations between skeletal muscle and adipose tissue quantified by computed tomography (CT) with postoperative complications and long-term prognosis in patients with rectal cancer after surgical resection.

METHODS

This retrospective cohort study included patients with rectal cancer who underwent surgical resection at the Wuhan Union Hospital between 2014 and 2018. CT images within 3 months prior to the surgery were used to quantify the indices of skeletal muscle and adipose tissue at the levels of the third lumbar vertebra (L3) and umbilicus. Optimal cut-off values for each index were defined separately for males and females. Associations between body composition and postoperative complications, overall survival (OS), and disease-free survival (DFS) were evaluated using logistic and Cox proportional hazards models.

RESULTS

We included 415 patients (240 males and 175 females; mean age: 57.8 ± 10.5 years). At the L3 level, a high skeletal muscle density (SMD; hazard ratio [HR]: 0.357, 95% confidence interval [CI]: 0.191-0.665, P = 0.001; HR: 0.571, 95% CI: 0.329-0.993, P = 0.047) and a high skeletal muscle index (SMI; HR: 0.435, 95% CI 0.254-0.747, P = 0.003; HR: 0.568, 95% CI: 0.359-0.897, P = 0.015) were independent prognostic factors for better OS and DFS. At the umbilical level, a large intermuscular fat area (IMFA; HR: 1.904, 95% CI: 1.068-3.395, P = 0.029; HR: 2.064, 95% CI: 1.299-3.280, P = 0.002) was an independent predictive factor for worse OS and DFS, and a high SMI (HR: 0.261, 95% CI: 0.132-0.517, P < 0.001; HR: 0.595, 95% CI: 0.387-0.913, P = 0.018) was an independent prognostic factor for better OS and DFS. The models combining body composition and clinical indicators had good predictive abilities for OS. The receiver operating characteristic areas under the curve were 0.848 and 0.860 at the L3 and umbilical levels, respectively (both P < 0.05).

CONCLUSIONS

No correlations existed between CT-quantified body composition parameters and postoperative complications. However, a high SMD and high SMI were significantly associated with longer OS and DFS at the L3 level, whereas a large IMFA and low SMI were associated with worse OS and DFS at the umbilical level. Combining CT-quantified body composition and clinical indicators could help physicians predict the prognosis of patients with rectal cancer after surgery.

Predicting the Feasibility of Curative Resection in Low Rectal Cancer: Insights from a Prospective Observational Study on Preoperative Magnetic Resonance Imaging Accuracy

Background and Objectives: A positive pathological circumferential resection margin is a key prognostic factor in rectal cancer surgery. The point of this prospective study was to see how well different MRI parameters could predict a positive pathological circumferential resection margin (pCRM) in people who had been diagnosed with rectal adenocarcinoma, either on their own or when used together. Materials and Methods: Between November 2019 and February 2023, a total of 112 patients were enrolled in this prospective study and followed up for a 36-month period. MRI predictors such as circumferential resection margin (mCRM), presence of extramural venous invasion (mrEMVI), tumor location, and the distance between the tumor and anal verge, taken individually or combined, were evaluated with univariate and sensitivity analyses. Survival estimates in relation to a pCRM status were also determined using Kaplan-Meier analysis. Results: When individually evaluated, the best MRI predictor for the detection of a pCRM in the postsurgical histopathological examination is mrEMVI, which achieved a sensitivity (Se) of 77.78%, a specificity (Sp) of 87.38%, a negative predictive value (NPV) of 97.83%, and an accuracy of 86.61%. Also, the best predictive performance was achieved by a model that comprised all MRI predictors (mCRM+ mrEMVI+ anterior location+ < 4 cm from the anal verge), with an Se of 66.67%, an Sp of 88.46%, an NPV of 96.84%, and an accuracy of 86.73%. The survival rates were significantly higher in the pCRM-negative group (p < 0.001). Conclusions: The use of selective individual imaging predictors or combined models could be useful for the prediction of positive pCRM and risk stratification for local recurrence or distant metastasis.

Sidedness is not a prognostic factor in an unselected cohort of patients with colon cancer but prognosis for caecal carcinoma is worse - A multivariate analysis of a large single institution database

PURPOSE

Sidedness has emerged as a prognostic factor for metastatic colorectal cancer treated with modern systemic therapies. This study investigates whether it is also relevant for an unselected patient cohort including all stages.

METHODS

All consecutive patients admitted with colon cancer between 1995 and 2018 were retrieved from an institution-held database. Patients were divided into two cohorts. The first cohort included patients without distant metastases who were able to undergo curative resection. The second cohort presented with distant metastases (stage IV). Potentially prognostic factors were subjected to multivariate Cox Regression analysis.

RESULTS

Overall, 1,606 patients met the inclusion and exclusion criteria. An R0-resection was achieved in 1,222 patients without distant metastases. Five-year cause-specific survival rate was 89.3% for this group. There was no difference between right- and left-sided cancers (88.2% vs. 90.1%, p = 0.220). However, prognosis of caecal carcinoma was significantly worse than that of all other sites combined (83.5% vs. 90.2%, p = 0.007). In multivariate analysis, pT-category, pN-category, grading, vascular invasion, emergency operation, adjuvant chemotherapy, and caecal carcinoma remained as independent prognostic factors. In the 384 patients with stage IV-disease, 3-year overall survival for right- vs. left-sided cancers differed only in univariate analysis (17.7% vs. 28.6%, p = 0.013).

CONCLUSION

In non-metastatic colon cancer, location in the caecum is an independent prognostic factor. In unselected patients with stage IV colon cancer, sidedness was not found to be a prognostic factor. Differentiation into right- and left-sided tumors may be simplistic, and further studies on the biological behavior of different colonic sites are warranted.

Zebrafish xenograft as a tool for the study of colorectal cancer: a review

Colorectal cancer (CRC) is the second leading cause of cancer-related death, mostly due to metastatic disease and the fact that many patients already show signs of metastasis at the time of first diagnosis. Current CRC therapies negatively impact patients' quality of life and have little to no effect on combating the tumor once the dissemination has started. Danio rerio (zebrafish) is a popular animal model utilized in cancer research. One of its main advantages is the ease of xenograft transplantation due to the fact that zebrafish larvae lack the adaptative immune system, guaranteeing the impossibility of rejection. In this review, we have presented the many works that choose zebrafish xenograft as a tool for the study of CRC, highlighting the methods used as well as the promising new therapeutic molecules that have been identified due to this animal model.

A predictive model for early death in elderly colorectal cancer patients: a population-based study

Purpose

The purpose of this study is to determine what variables contribute to the early death of elderly colorectal cancer patients (ECRC) and to generate predictive nomograms for this population.

Methods

This retrospective cohort analysis included elderly individuals (≥75 years old) diagnosed with colorectal cancer (CRC) from 2010-2015 in the Surveillance, Epidemiology, and End Result databases (SEER) databases. The external validation was conducted using a sample of the Chinese population obtained from the China-Japan Union Hospital of Jilin University. Logistic regression analyses were used to ascertain variables associated with early death and to develop nomograms. The nomograms were internally and externally validated with the help of the receiver operating characteristic curve (ROC), calibration curve, and decision curve analysis (DCA).

Results

The SEER cohort consisted of 28,111 individuals, while the Chinese cohort contained 315 cases. Logistic regression analyses shown that race, marital status, tumor size, Grade, T stage, N stage, M stage, brain metastasis, liver metastasis, bone metastasis, surgery, chemotherapy, and radiotherapy were independent prognostic factors for all-cause and cancer-specific early death in ECRC patients; The variable of sex was only related to an increased risk of all-cause early death, whereas the factor of insurance status was solely associated with an increased risk of cancer-specific early death. Subsequently, two nomograms were devised to estimate the likelihood of all-cause and cancer-specific early death among individuals with ECRC. The nomograms exhibited robust predictive accuracy for predicting early death of ECRC patients, as evidenced by both internal and external validation.

Conclusion

We developed two easy-to-use nomograms to predicting the likelihood of early death in ECRC patients, which would contribute significantly to the improvement of clinical decision-making and the formulation of personalized treatment approaches for this particular population.

Recurrence Patterns and Risk Factors after Curative Resection for Colorectal Cancer: Insights for Postoperative Surveillance Strategies

This study aimed to assess recurrence patterns and related risk factors following curative resection of colorectal cancer (CRC). This retrospective observational study was conducted at a tertiary care center, including 2622 patients with stage I-III CRC who underwent curative resection between 2008 and 2018. Hazard rates of recurrence were calculated using a hazard function. The primary outcome was the peak recurrence time after curative resection and secondary outcomes were prognostic factors associated with recurrence. Over a median follow-up period of 53 months, the overall, locoregional and systemic recurrence rates were 8.9%, 0.7%, and 8.5%, respectively. Recurrence rates were significantly higher for rectal cancer (14.9% overall, 4.4% locoregionally, and 12.3% systemically) than for colon cancer (all p < 0.001). The peak recurrence time was 11 months, with variations in hazard rates and curves depending on the tumor location, stage, and risk factors. Patients with AL or CRM involvement exhibited a distinct pattern, with a high hazard rate in the early postoperative period. Understanding these recurrence patterns and risk factors is crucial for establishing effective postoperative surveillance strategies. Our findings suggested that short-interval surveillance should be considered during the first 2 years post-surgery, particularly for high-risk patients who should receive early attention.

NXNL2 Promotes Colon Cancer Proliferation and Metastasis by Regulating AKT Pathway

This study aimed to explore the role of nucleoredoxin-like 2 (NXNL2) in colon cancer (CC). The GEPIA and UALCAN databases were analyzed to explore genes involved in the prognosis of CC patients. DLD1 cells were treated with the DNA methylation inhibitor 5-azacitidine to validate the above findings. The methyltransferase DNMT (DNA methylation) was further knocked down by shRNA, then the expression of NXNL2 was assessed by qPCR. The role of NXNL2 on cell proliferation and metastasis was examined using corresponding assays. NXNL2 was found to exhibit the greatest impact on the prognosis of CC patients. High NXNL2 correlated with poor survival outcomes of CC. The expression of NXNL2 was regulated by DNA methylation. NXNL2 promoted CC cell proliferation and metastasis. Also, NXNL2 promoted the AKT pathway activity. In conclusion, NXNL2 could affect the cancer cell proliferation and metastasis, and has a poor survival prognosis in CC.

Bibliometric analysis and visualization of research trends in total mesorectal excision in the past twenty years

BACKGROUND

Rectal cancer leads a major disease burden worldwide. Total mesorectal excision (TME) is the standard treatment for locally advanced or node-positive rectal cancer, while attempts to improve the surgery such as laparoscopic and transanal TME are widely used but have their inherent limitations. This bibliometric study analyzed research trends, cooperation, and knowledge dissemination on TME over the past 20 years to inform future directions.

METHODS

Relevant literature from 2003 to 2023 was extracted from the Web of Science Core Collection and analyzed with VOSviewer, CiteSpace, and R for publication patterns, countries, institutions, authors, and research hotspots.

RESULTS

Five thousand three hundred forty-five related publications were included, with rising annual output and citations. The US and China contributed the most studies, while the Netherlands had greater influence. Leiden University ranked first in publications. The top authors were Heald, Kapiteijn, Sauer, Nagtegaal, and Peeters. Research shifted from cancer-focused to patient-centered care and from radiotherapy/chemotherapy to advanced surgery. Multicenter trials became more common.

CONCLUSION

Although the United States and China have the largest number of publications, it should be noted that the influence of these two countries in the field of TME research is not the highest, which does not match the number of publications. In addition, telemedicine, interdisciplinary, medical-industrial integration, etc. may be potential directions for future research in the field of TME.

Prognostic impact of colorectal cancer patients with bone metastases: a single-center experience

The incidence of bone metastasis (BM) in colorectal cancer (CRC) patients is low and the prognosis is poor. There is no clear conclusion on the risk factors affecting the survival of CRC patients with BM. The aim of this study was to investigate the factors that may affect the prognosis of CRC patients with BM. The clinical and pathological data of CRC patients with BM were retrospectively analyzed. The overall survival after BM diagnosis was estimated using the Kaplan-Meier method and Log-rank test, and a multivariable cox regression model was used to identify the prognostic factors of overall survival. This study included 178 CRC patients with BM, of whom 151 had left-sided CRC and 27 had right-sided colon cancer. 1124 CRC patients with BM from the SEER database were included to perform a sensitivity analysis of the primary outcome. Multivariate analysis showed that the N staging, site of BM, and primary tumor sidedness (PTS) were independent prognostic factors for CRC with BM. Among them, right-sided colon cancer patients with BM had a poorer prognosis. Sensitivity analyses showed that PTS was an independent prognostic factor in CRC patients with BM. Primary tumor sidedness and N stage may be potential prognostic markers for BM of CRC. The prognosis of N0 stage CRC with BM is better, while the prognosis of right-sided colon cancer is poor.

Perioperative and Oncological Outcomes of Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy for Peritoneal Metastasis of Rectal Origin

BACKGROUND

The peritoneum is a common metastatic site of colorectal cancer (CRC) and associated with worse oncological outcomes. Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) has been shown to improve outcomes in selected patients. Studies have demonstrated significant difference in survival of patients with primary colon and rectal tumors both in local and in metastatic setting; but only few assessed outcomes of CRS/HIPEC for rectal and colon tumors. We studied the perioperative and oncological outcomes of patients undergoing CRS/HIPEC for rectal cancer.

METHODS

A retrospective analysis of a prospectively maintained database between 2009 and 2021 was performed.

RESULTS

199 patients underwent CRS/HIPEC for CRC. 172 patients had primary colon tumors and 27 had primary rectal tumors. Primary rectal location was associated with longer surgery (mean 4.32, hours vs 5.26 h, p = 0.0013), increased blood loss (mean 441cc vs 602cc, p = 0.021), more blood transfusions (mean 0.77 vs 1.37units, p = 0.026) and longer hospitalizations (mean 10 days vs 13 days, p = 0.02). Median disease-free survival (DFS) was shorter in rectal primary group; 7.03 months vs 10.9 months for colon primaries (p = 0.036). Overall survival was not statistically significant; 53.2 months for rectal and 60.8 months for colon primary tumors. Multivariate analysis indicated origin (colon vs rectum) and Peritoneal Cancer Index to be independently associated with DFS.

CONCLUSIONS

Patients with rectal carcinoma undergoing CRS/HIPEC for peritoneal metastasis had worse peri-operative and oncological outcomes. Overall survival was excellent in both groups. This data may be used for risk stratification when considering CRS/HIPEC for patients with rectal primary.

A Retrospective Comparison of Toxicity, Response and Survival of Intensity-Modulated Radiotherapy Versus Three-Dimensional Conformal Radiation Therapy in the Treatment of Rectal Carcinoma

INTRODUCTION

The main target of neoadjuvant treatment in rectal cancer is to downstage and downsize large tumours to increase the chance of complete surgical resection, and therefore decrease the chances of local recurrence. With or without the addition of chemotherapy, until recently, three-dimensional conformal radiotherapy (3D-CRT) used to be the radiotherapy treatment modality of choice. However, intensity-modulated radiotherapy (IMRT) is being increasingly adopted by many radiotherapy centres as a more modern, conformal technique due to its ability to minimize radiation dose to nearby organs. The aim of our analysis was to assess the difference in toxicity, response to treatment, and survival between the patients treated with these two different treatment modalities in our institution.

METHODS

We performed a retrospective analysis of data and compared two groups of patients with locally advanced rectal cancer who were treated with either 3D-CRT or IMRT. The main outcomes were radiation toxicity and response to treatment. Overall survival was a secondary outcome.

RESULTS

One hundred and thirty-six patients were included in the study: 71 patients treated with 3D-CRT and 65 patients treated with IMRT. With regard to toxicity, there was no significant difference between the groups for bladder and skin toxicity, but there was a significant reduction in acute grade 2 bowel toxicity in patients treated with a long course of IMRT [3D-CRT 77% (48/62) vs IMRT 64% (30/47) p=0.042]. There was no statistically significant difference in the treatment response rates of these two radiotherapy treatment modalities, as well as in overall survival between the groups (p=0.604).  Conclusion: Our study showed that IMRT can significantly reduce acute bowel side effects for patients undergoing neoadjuvant radiotherapy for locally advanced rectal cancers. Further studies are needed to confirm the clinical advantage of IMRT in rectal carcinoma.

Implications of Rectal Cancer Radiotherapy on the Immune Microenvironment: Allies and Foes to Therapy Resistance and Patients' Outcome

Aside from surgical resection, locally advanced rectal cancer is regularly treated with neoadjuvant chemoradiotherapy. Since the concept of cancer treatment has shifted from only focusing on tumor cells as drivers of disease progression towards a broader understanding including the dynamic tumor microenvironment (TME), the impact of radiotherapy on the TME and specifically the tumor immune microenvironment (TIME) is increasingly recognized. Both promoting as well as suppressing effects on anti-tumor immunity have been reported in response to rectal cancer (chemo-)radiotherapy and various targets for combination therapies are under investigation. A literature review was conducted searching the PubMed database for evidence regarding the pleiotropic effects of (chemo-)radiotherapy on the rectal cancer TIME, including alterations in cytokine levels, immune cell populations and activity as well as changes in immune checkpoint proteins. Radiotherapy can induce immune-stimulating and -suppressive alterations, potentially mediating radioresistance. The response is influenced by treatment modalities, including the dosage administered and the highly individual intrinsic pre-treatment immune status. Directly addressing the main immune cells of the TME, this review aims to highlight therapeutical implications since efficient rectal cancer treatment relies on personalized strategies combining conventional therapies with immune-modulating approaches, such as immune checkpoint inhibitors.

Impact of the SARS-CoV-2 on the journey of high-risk colon cancer patients within the scope of the Unified Health System in Brazil

BACKGROUND

Colon cancer is an important cause of mortality related to cancer. During the COVID-19 pandemic, an important reallotment of assistance resources was necessary to tackle the crisis, directly impacting medical practice all over the globe.

OBJECTIVE

To assess the impact of the Sars-Cov-2 pandemic on the time between diagnosis and the beginning of systemic treatment in patients diagnosed with high-risk colon neoplasia.

METHODS

This is a retrospective study based on the analysis of medical records of patients diagnosed with colon neoplasia who required systemic treatment and were treated between March 2019 and March 2022, in a reference Oncology unit of the Brazilian Unified Health System. The study's population was divided into two groups: (I) Pre-COVID-19: diagnoses made between March 2019 and February 2020, (II) COVID-19: diagnoses made between March 2020 and March 2022.

RESULTS

The sample consisted of 228 patients, 108 (47.97%) of whom were diagnosed during pre-COVID-19 and 118 (52.21%) diagnosed during the two years-period of COVID-19. Regarding the time between colonoscopy and surgery, the time between surgery and first consultation in clinical oncology, and the time between requesting and beginning of systemic treatment, a statistically significant reduction was observed during the COVID-19 period.

CONCLUSION

A decrease in time between diagnosis and systemic treatment of patients with colorectal cancer during the COVID-19 pandemic was observed. Yet, even with this improvement, the time to begin treatment remains greater than the recommended by the current guidelines, regardless of the time of diagnosis (before or after the pandemic), which negatively impacts the disease outcome.

Predicting survival and prognosis in early-onset locally advanced colon cancer: a retrospective observational study

OBJECTIVE

To predict cancer-specific survival, a refined nomogram model and brand-new risk-stratifying system were established to classify the risk levels of patients with early-onset locally advanced colon cancer (LACC).

METHODS

The clinical factors and survival outcomes of LACC cases from the SEER database from 2010 to 2019 were retrieved retrospectively. Early-onset and late-onset colon cancer were grouped according to the age (50 years old) at diagnosis. Differences between groups were compared to identify mutual significant variables. A multivariate Cox regression analysis was further performed and then constructed a nomogram. We compared it with the AJCC-TNM system. The external validation was performed for evaluation. Finally, a risk-stratifying system of patients with early-onset LACC was established.

RESULTS

A total of 32,855 LACC patients were enrolled in, 4548 (13.84%) patients were included in the early-onset LACC group, and 28,307 (86.16%) patients were included in the late-onset LACC group. The external validation set included 228 early-onset LACC patients. Early-onset colon cancers had poorer prognosis (T4, N2, TNM stage III, CEA, tumor deposit, and nerve invasion), and a higher proportion received radiotherapy and systemic therapy (P<0.001). In the survival analysis, cancer-specific survival (CSS) was better in patients with early-onset LACC than in those with late-onset LACC (P <0.001). This nomogram constructed based on the results of COX analysis showed better accuracy in CSS prediction of early-onset LACC patients than AJCC-TNM system in the training set and external validation set (0.783 vs 0.728; 0.852 vs 0.773).

CONCLUSION

We developed a novel nomogram model to predict CSS in patients with early-onset LACC it provided a reference in prognosis prediction and selection of individualized treatment, helping clinicians in decision-making.

Clinical Significance of Combining Preoperative and Postoperative Albumin-Bilirubin Score in Colorectal Cancer

PURPOSE

Albumin-bilirubin (ALBI) score is a well-known prognostic factor for various diseases, including colorectal cancer (CRC). However, little is known about the significance of postoperative ALBI score changes in patients with CRC.

MATERIALS AND METHODS

A total of 723 patients who underwent surgery were enrolled. Preoperative ALBI (ALBI-pre) and postoperative ALBI (ALBI-post) scores were divided into low and high score groups. ALBI-trend was defined as a combination of four groups comprising the low and high ALBI-pre and ALBI-post score groups. Kaplan-Meier survival curves were used to compare the overall survival (OS) between the different ALBI groups. The Cox proportional hazards model was used to examine the independent relevant factors of OS. Stratification performance was compared between the different ALBI groupings using Harrell's concordance index (C-index).

RESULTS

ALBI-pre, ALBI-post, and ALBI-trend score groups were significant prognostic factors of OS in the univariable analysis. However, multivariable analysis showed that ALBI-trend was an independent prognostic factor while ALBI-pre and ALBI-post were not. The C-index of ALBI-trend (0.622; 95% confidence interval [CI], 0.587 to 0.655) was higher than that of ALBI-pre (0.589; 95% CI, 0.557 to 0.621; bootstrap mean difference, 0.033; 95% CI, 0.013 to 0.057) and ALBI-post (0.575; 95% CI, 0.545 to 0.605; bootstrap mean difference, 0.047; 95% CI, 0.024 to 0.074).

CONCLUSION

Combining ALBI-pre and ALBI-post scores is an independent prognostic factor of OS and shows superior predictive power compared to ALBI-pre or ALBI-post alone in patients with CRC.

The psoas muscle density as a predictor of postoperative complications in elderly patients undergoing rectal cancer resection

Background

Muscle depletion that impairs normal physiological function in elderly patients leads to poor prognosis. This study aimed to evaluate the association between total abdominal muscle area (TAMA), total psoas area (TPA), psoas muscle density (PMD), and short-term postoperative complications in elderly patients with rectal cancer.

Methods

All elderly patients underwent rectal cancer resection with perioperative abdominal computed tomography (CT). Complications were assessed according to the Clavien-Dindo classification. Severe complications were defined as grade III-V following the Clavien-Dindo classification. Univariate and multivariate analyses were performed to evaluate risk factors of short-term severe postoperative complications.

Results

The cohort consisted of 191 patients with a mean age of 73.60 ± 8.81 years. Among them, 138 (72.25%) patients had Clavien-Dindo 0- II, 53 (27.75%) patients had severe postoperative complications (Clavien-Dindo III-V), and 1(0.52%) patient died within 30 days of surgery. PMD was significantly higher in the Clavien-Dindo 0-II cohort compared to the Clavien-Dindo III-V cohort (p=0.004). Nevertheless, TAMA and TPA failed to exhibit significant differences. Moreover, the multivariate regression analysis implied that advanced age [OR 1.07 95%CI (1.02-1.13) p=0.013], male [OR 5.03 95%CI (1.76-14.41) p=0.003], high charlson comorbidity index (CCI) score [OR 3.60 95%CI (1.44-9.00) p=0.006], and low PMD [OR 0.94 95%CI (0.88-0.99) p=0.04] were independent risk factors of Clavien-Dindo III-V.

Conclusion

Preoperative assessment of the PMD on CT can be a simple and practical method for identifying elderly patients with rectal cancer at risk for severe postoperative complications.

Comorbidity Patterns in Patients Newly Diagnosed With Colorectal Cancer: Network-Based Study

BACKGROUND

Patients with colorectal cancer (CRC) often present with multiple comorbidities, and many of these can affect treatment and survival. However, previous comorbidity studies primarily focused on diseases in commonly used comorbidity indices. The comorbid status of CRC patients with respect to the entire spectrum of chronic diseases has not yet been investigated.

OBJECTIVE

This study aimed to systematically analyze all chronic diagnoses and diseases co-occurring, using a network-based approach and large-scale administrative health data, and provide a complete picture of the comorbidity pattern in patients newly diagnosed with CRC from southwest China.

METHODS

In this retrospective observational study, the hospital discharge records of 678 hospitals from 2015 to 2020 in Sichuan Province, China were used to identify new CRC cases in 2020 and their history of diseases. We examined all chronic diagnoses using ICD-10 (International Classification of Diseases, 10th Revision) codes at 3 digits and focused on chronic diseases with >1% prevalence in at least one subgroup (1-sided test, P<.025), which resulted in a total of 66 chronic diseases. Phenotypic comorbidity networks were constructed across all CRC patients and different subgroups by sex, age (18-59, 60-69, 70-79, and ≥80 years), area (urban and rural), and cancer site (colon and rectum), with comorbidity as a node and linkages representing significant correlations between multiple comorbidities.

RESULTS

A total of 29,610 new CRC cases occurred in Sichuan, China in 2020. The mean patient age at diagnosis was 65.6 (SD 12.9) years, and 75.5% (22,369/29,610) had at least one comorbidity. The most prevalent comorbidities were hypertension (8581/29,610, 29.0%; 95% CI 28.5%-29.5%), hyperplasia of the prostate (3816/17,426, 21.9%; 95% CI 21.3%-22.5%), and chronic obstructive pulmonary disease (COPD; 4199/29,610, 14.2%; 95% CI 13.8%-14.6%). The prevalence of single comorbidities was different in each subgroup in most cases. Comorbidities were closely associated, with disorders of lipoprotein metabolism and hyperplasia of the prostate mediating correlations between other comorbidities. Males and females shared 58.3% (141/242) of disease pairs, whereas male-female disparities occurred primarily in diseases coexisting with COPD, cerebrovascular diseases, atherosclerosis, heart failure, or renal failure among males and with osteoporosis or gonarthrosis among females. Urban patients generally had more comorbidities with higher prevalence and more complex disease coexistence relationships, whereas rural patients were more likely to have co-existing severe diseases, such as heart failure comorbid with the sequelae of cerebrovascular disease or COPD.

CONCLUSIONS

Male-female and urban-rural disparities in the prevalence of single comorbidities and their complex coexistence relationships in new CRC cases were not due to simple coincidence. The results reflect clinical practice in CRC patients and emphasize the importance of measuring comorbidity patterns in terms of individual and coexisting diseases in order to better understand comorbidity patterns.

Differential Efficacy of Targeted Monoclonal Antibodies in Left-Sided Colon and Rectal Metastatic Cancers

BACKGROUND

The recommended first-line chemotherapy for RAS/BRAF wild-type metastatic colorectal cancer (mCRC) is bevacizumab (BEV)-containing therapy for right-sided colon cancer (R) and antiepidermal growth factor receptor antibody (anti-EGFR)-containing therapy for left-sided colon cancer (L) or rectal cancer (RE). However, anatomical or biological heterogeneity reportedly exists between L and RE. Therefore, we aimed to compare the efficacies of anti-EGFR and BEV therapies for L and RE, respectively.

METHODS

We retrospectively reviewed 265 patients with KRAS (RAS)/BRAF wild-type mCRC treated with fluoropyrimidine-based doublet chemotherapy plus anti-EGFR or BEV as the first-line treatment at a single institution. They were divided into 3 groups: R, L, and RE. Overall survival (OS), progression-free survival (PFS), objective response rate, and conversion surgery rate were analyzed.

RESULTS

Forty-five patients had R (anti-EGFR/BEV: 6/39), 137 patients had L (45/92), and 83 patients had RE (25/58). In patients with R, both median (m) PFS and OS were superior with BEV therapy (mPFS, anti-EGFR vs. BEV: 8.7 vs. 13.0 months, hazard ratio [HR]: 3.90, P = .01; mOS, 17.1 vs. 33.9 months, HR: 1.54, P = .38). In patients with L, better mPFS and comparable mOS with anti-EGFR therapy were observed (mPFS, 20.0 vs. 13.4 months, HR: 0.68, P = .08; mOS, 44.8 vs. 36.0 months, HR: 0.87, P = .53), whereas, in patients with RE, comparable mPFS and worse mOS with anti-EGFR therapy were observed (mPFS, 17.2 vs. 17.8 months, HR: 1.08, P = .81; mOS, 29.1 vs. 42.2 months, HR: 1.53, P = .17).

CONCLUSIONS

Efficacies of anti-EGFR and BEV therapies may differ between patients with L and RE.

A predictive role of C-reactive protein in colorectal cancer risk: an updated meta-analysis from 780,985 participants and 11,289 cancer cases

PURPOSE

This meta-analysis is aimed at understanding the potential role of circulating C-reactive protein (CRP) in the prediction of colorectal cancer (CRC) risk and the potential effect of relevant variables, with specific concern to determine the incorporation of CRP into a CRC risk prediction model.

METHODS

Relevant articles on the association between circulating CRP and CRC risk were searched from PubMed, Embase, Web of Science, and Cochrane Database of Systematic Reviews through August 2022. Random-effects models were used to estimate the pooled relative risk (RR) for the highest versus lowest CRP categories. Linear and non-linear trend analyses were conducted to explore the dose-response associations between CRP and CRC risk.

RESULTS

Twenty-three articles including 780,985 participants and 11,289 cancer cases met the selection criteria. The overall result demonstrated a remarkable association between elevated CRP levels and CRC risk (RR, 1.259; 95% CI, 1.060-1.457), but not in dose-response analysis (RR, 1.002 (95% CI, 0.964-1.041) per natural log unit change in CRP). Subgroup analyses indicated a significant difference when grouped by study location, the length of follow-up, and gender composition. No evidence of publication bias was observed.

CONCLUSION

The predictive role of CRP in CRC incidence is limited to colon cancer and a period of 10 years after the initial discovery of CRP elevation. The result did not support the etiological role of CRP in CRC and the inclusion of CRP into the CRC risk prediction model.

The current understanding of the immune landscape relative to radiotherapy across tumor types

Radiotherapy is part of the standard of care treatment for a great majority of cancer patients. As a result of radiation, both tumor cells and the environment around them are affected directly by radiation, which mainly primes but also might limit the immune response. Multiple immune factors play a role in cancer progression and response to radiotherapy, including the immune tumor microenvironment and systemic immunity referred to as the immune landscape. A heterogeneous tumor microenvironment and the varying patient characteristics complicate the dynamic relationship between radiotherapy and this immune landscape. In this review, we will present the current overview of the immunological landscape in relation to radiotherapy in order to provide insight and encourage research to further improve cancer treatment. An investigation into the impact of radiation therapy on the immune landscape showed in several cancers a common pattern of immunological responses after radiation. Radiation leads to an upsurge in infiltrating T lymphocytes and the expression of programmed death ligand 1 (PD-L1) which can hint at a benefit for the patient when combined with immunotherapy. In spite of this, lymphopenia in the tumor microenvironment of 'cold' tumors or caused by radiation is considered to be an important obstacle to the patient's survival. In several cancers, a rise in the immunosuppressive populations is seen after radiation, mainly pro-tumoral M2 macrophages and myeloid-derived suppressor cells (MDSCs). As a final point, we will highlight how the radiation parameters themselves can influence the immune system and, therefore, be exploited to the advantage of the patient.

Risk and location of distant metastases in patients with locally advanced rectal cancer after total neoadjuvant treatment or chemoradiotherapy in the RAPIDO trial

INTRODUCTION

Although optimising rectal cancer treatment has reduced local recurrence rates, many patients develop distant metastases (DM). The current study investigated whether a total neoadjuvant treatment strategy influences the development, location, and timing of metastases in patients diagnosed with high-risk locally advanced rectal cancer included in the Rectal cancer And Pre-operative Induction therapy followed by Dedicated Operation (RAPIDO) trial.

MATERIAL AND METHODS

Patients were randomly assigned to short-course radiotherapy followed by 18 weeks of CAPOX or FOLFOX4 before surgery (EXP), or long-course chemoradiotherapy with optional postoperative chemotherapy (SC-G). Assessments for metastatic disease were performed pre- and post-treatment, during surgery, and 6, 12, 24, 36, and 60 months postoperatively. From randomisation, differences in the occurrence of DM and first site of metastasis were evaluated.

RESULTS

In total, 462 patients were evaluated in the EXP and 450 patients in the SC-G groups. The cumulative probability of DM at 5 years after randomisation was 23% [95% CI 19-27] and 30% [95% CI 26-35] (HR 0.72 [95% CI 0.56-0.93]; P = 0.011) in the EXP and SC-G, respectively. The median time to DM was 1.4 (EXP) and 1.3 years (SC-G). After diagnosis of DM, median survival was 2.6 years [95% CI 2.0-3.1] in the EXP and 3.2 years [95% CI 2.3-4.1] in the SC-G groups (HR 1.39 [95% CI 1.01-1.92]; P = 0.04). First occurrence of DM was most often in the lungs (60/462 [13%] EXP and 55/450 [12%] SC-G) or the liver (40/462 [9%] EXP and 69/450 [15%] SC-G). A hospital policy of postoperative chemotherapy did not influence the development of DM.

CONCLUSIONS

Compared to long-course chemoradiotherapy, total neoadjuvant treatment with short-course radiotherapy and chemotherapy significantly decreased the occurrence of metastases, particularly liver metastases.

Survival outcomes after synchronous para-aortic lymph node metastasis in colorectal cancer: A systematic review

BACKGROUND

Synchronous para-aortic lymph node metastasis (PALNM) in colorectal cancer (CRC) is a relatively rare clinical entity. There is a lack of consensus on management of these patients, and the role of para-aortic lymph node dissection (PALND) remains controversial. This systematic review aims to describe the survival outcomes in colorectal cancer with synchronous PALNM when lymph node dissection is performed.

METHODS

A systematic review of Pubmed, Embase and Web of Science databases for PALND in CRC was performed. Studies including patients with synchronous PALNM undergoing resection with curative intent, published from the year 2000 onwards, were included.

RESULTS

Twelve retrospective studies were included. Four studies reported survival outcomes for rectal cancer, two for colon cancer and six as colorectal. Survival outcomes for 356 patients were included. Average 5-year overall survival (OS) was 22.4%, 33.9% and 37.7% in the rectal, colon and colorectal groups respectively. Three year OS in the groups was 53.6%, 46.2% and 65.7%.

CONCLUSION

There remains a lack of quality data to confidently make recommendations regarding the management of synchronous PALNM in colon and rectal cancer cohorts. Retrospective data suggests a benefit in highly selective cohorts and therefore a case-by-case evaluation remains the standard of care.

Effects of Polyunsaturated Fatty Acids on Colorectal Cancer Patients: A Meta-Analysis of Randomized Controlled Trials

This study aimed to investigate the effects of polyunsaturated fatty acids (PUFAs) on patients with colorectal cancer (CRC). Electronic databases such as PubMed and Web of Science were searched. Studies on the application of PUFAs in patients with CRC, published up to January 2022, were conducted. Twelve studies involving 702 CRC patients were included. For patients undergoing surgery, subgroup analyses indicated that preoperative supplementation with PUFAs improved total postoperative infectious complications (RR: 0.37, p = 0.02). Furthermore, the supplementation of PUFAs in preoperative (WMD: -2.27, p < 0.001) and postoperative (WMD: -2.66, p = 0.01) groups was effective in shortening the postoperative hospital stay for patients with CRC. Tumor necrosis factor-α (TNF-α) (SMD: -0.56, p = 0.007) and interleukin-6 (IL-6) (SMD: -0.54, p = 0.004) levels were lower in all CRC patients receiving PUFAs intervention than in the control group. Moreover, supplementation with PUFAs in chemotherapy patients significantly increased albumin (WMD: 0.48, p = 0.03) and decreased C-reactive protein (CRP) (WMD: -6.12, p = 0.02) compared to the control group. This study demonstrated that PUFAs intervention could diminish the total postoperative infection complications of CRC patients, shorten the postoperative hospital stay, and reduce inflammation.

New Horizons in Metastatic Colorectal Cancer: Prognostic Role of CD44 Expression

BACKGROUND

The transmembrane glycoprotein CD44, the major hyaluronan (HA) receptor, has been proven to regulate cell growth, survival, differentiation, and migration. It is therefore widely considered to be involved in carcinogenesis. Its role as a new therapeutic target in solid tumors is under evaluation in clinical trials. The prognostic value remains controversial. Here, we aimed to investigate the correlation between CD44 expression and the clinicopathological features and survival in metastatic colorectal cancer (mCRC) patients.

METHODS

Data from 65 mCRC patients of the Medical Oncology Unit, University Hospital and University of Cagliari were retrospectively collected from 2008 to 2021. Immunohistochemical analysis was performed at the Pathology Division, University Hospital of Cagliari on 3 μm thick sections obtained from paraffin blocks. The intensity of immunohistochemical staining was subclassified into four groups: score 0 if negative or weak membrane staining in less than 10% of tumor cells; score 1+ if weak membrane staining in at least 10% of tumor cells or moderate membrane staining in less than 10% of tumor cells; score 2+ if moderate membrane staining in at least 10% of tumor cells or intensive membrane staining in less than 10% of tumor cells; score 3+ if intense membrane staining in at least 10% of tumor cells. Based on this score, we distinguished patients into low CD44 expression (score 0, 1+, 2+) and high CD44 expression (score 3+). Statistical analysis was performed with MedCalc (survival distribution: Kaplan-Meier; survival comparison: log-rank test; association between categorical variables: Fisher's exact test).

RESULTS

Patients' median age was 66 years (range 49-85). Regarding CD44 expression, score was 0 in 18 patients, 1+ in 15 patients, 2+ in 18 patients, and 3+ in 14 patients. Median overall survival (mOS) was 28.1 months (95%CI: 21.3-101). CD44 overexpression (3+) was correlated with poor prognosis (p = 0.0011; HR = 0.2), with a mOS of 14.5 months (95%CI 11.7 to 35.9) versus 30.7 months (95%CI 27.8 to 101) in lower CD44 expression. Higher CD44 expression was associated with clinically poor prognostic features: age ≥ 70 years (p = 0.0166); inoperable disease (p = 0.0008); stage IV at diagnosis (p = 0.0241); BRAF mutated (p = 0.0111), high-grade tumor (p = 0.0084).

CONCLUSIONS

CD44 markedly correlated with aggressive tumor behavior and contributed to the earlier progression of disease, thus suggesting its role as a novel prognostic marker and potential therapeutic target for mCRC patients.

Influence of Sex and Age on Site of Onset, Morphology, and Site of Metastasis in Colorectal Cancer: A Population-Based Study on Data from Four Italian Cancer Registries

The prognosis of colorectal cancer is affected by factors such as site of origin, tumor morphology, and metastasis at diagnosis, but also age and sex seem to play a role. This study aimed to investigate within the Italian population how sex and age interact in influencing certain aspects of the disease and how they affect patient survival, particularly in the metastatic cohort. Data from four cancer registries were collected, and patients were classified by sex and age (<50, 50-69, and >69 years). Two separate analyses were conducted: one for patients having right or left colon cancer with adenocarcinoma or mucinous morphology, and one for patients having metastases at diagnosis. Women showed significant differences in right colon cases from the youngest to oldest age group (36% vs. 45% vs. 60%). Men <50 years had a significantly higher mucinous carcinoma percentage than their female counterparts (22% vs. 11%), while in the oldest age group women had the highest percentage (15% vs. 11%). The metastatic pattern differed between men and women and by age. The three-year relative survival in the <50 age group was better for women than men, but this survival advantage was reversed in the oldest group. In conclusion, sex and age are factors that influence the biological and clinical characteristics of colorectal cancer, affecting the metastatic pattern as well as patient survival.

Expression patterns and prognostic value of key regulators associated with m7G RNA modification based on all gene expression in colon adenocarcinoma

BACKGROUND

N7-methylguanosine (m7G) is present in a wide variety of organisms and has important roles. m7G has been reported to be involved in multiple biological processes, and recent studies have reported that changes in RNA modifications result in tumor cellular transformation and cancer, such as colon adenocarcinoma, lung cancer, and intrahepatic cholangiocarcinoma. However, little is known about the function of the m7G in colon adenocarcinoma.

METHODS

We established two clusters based on the expression of all genes associated with m7G to explore the expression pattern of 31 key regulatory factors of m7G RNA and assess the prognostic value of regulatory factors. Wilcoxon test and differential box line plots were applied for bioinformatics analysis. Receiver Operating and Kaplan‒Meier curves were utilized to evaluate the prognostic value. Finally, four genes' expression in the colon cancer cell line was confirmed by qRT-PCR.

RESULTS

From The Cancer Genome Atlas database, we found that the expression levels of 25 out of the 31 key N7-methylguanosine RNA modification regulators were significantly different in colon adenocarcinoma. According to 25 methylation regulators' expression, we identified two subgroups by consensus clustering, in which the prognosis was worse in Group 2 than in Group 1 and was significantly correlated with age. Cluster 2 was significantly enriched in tumor-associated pathways, and immune cells were highly infiltrated in Cluster 1 but weakly infiltrated in Cluster 2. Further results indicated that this risk profile may serve as a standalone predictive factor for colon adenocarcinoma, and the four genetic risk profiles' prognostic relatedness was successfully verified through Gene Expression Omnibus dataset. At last, A nomogram for prognosis was created according to age, sex, histological grading, clinicopathological staging, and hazard score to accurately predict patient prognosis in colon adenocarcinoma. We successfully validated the differential expression of four genes using qRT-PCR.

CONCLUSIONS

In the present study, we revealed the important contribution of key regulators associated with m7G RNA modifications based on all gene expression in colon adenocarcinoma and developed a signature of risk that serves as a promising prognostic marker for patients with colon adenocarcinoma.

Development of prediction model of low anterior resection syndrome for colorectal cancer patients after surgery based on machine-learning technique

BACKGROUND

Low anterior resection syndrome (LARS) is a common postoperative complication in patients with colorectal cancer, which seriously affects their postoperative quality of life. At present, the aetiology of LARS is still unclear, but some risk factors have been studied. Accurate prediction and early management of medical intervention are keys to improving the quality of life of such high-risk patients.

OBJECTIVES

Based on machine-learning methods, this study used the follow-up results of postoperative patients with colorectal cancer to develop prediction models for LARS and conducted a comparative analysis between the different models.

METHODS

A total of 382 patients diagnosed with colorectal cancer and undergoing surgery at West China Hospital from April 2017 to December 2020 were retrospectively selected as the development cohort. Logistic regression, support vector machine, decision tree, random forest and artificial neural network algorithms were used to construct the prediction models of the obtained dataset. The models were internally validated using cross-validation. The area under the curve and Brier score measures were used to evaluate and compare the differentiation and calibration degrees of the models. The sensitivity, specificity, positive predictive value and negative predictive value of the different models were described for clinical use.

RESULTS

A total of 342 patients were included, the incidence of LARS being 47.4% (162/342) during the six-month follow-up. After feature selection, the factors influencing the occurrence of LARS were found to be location, distance, diverting stoma, exsufflation and surgical type. The prediction models based on five machine-learning methods all showed acceptable performance.

CONCLUSIONS

The five models developed based on the machine-learning methods showed good prediction performance. However, considering the simplicity of clinical use of the model results, the logistic regression model is most recommended. The clinical applicability of these models will also need to be evaluated with external cohort data.

Risk factors for right colon, left colon and rectal cancers differ between men and women: the population-based HUNT study in Norway

AIM

The aim of this study was to assess established risk factors for colorectal cancer (CRC) separately for right colon, left colon and rectal cancer in men and women.

METHOD

This was a prospective cohort study comparing incidental CRC cases and the general population participating in a longitudinal health study in Norway (the HUNT study).

RESULTS

Among 78 580 participants (36 825 men and 41 754 women), 1827 incidental CRCs were registered (931 men and 896 women). Among men, the risk of cancer at all locations increased with age [HR 1.46 (1.40-1.51), HR 1.32 (1.27-1.36), HR 1.30 (1.25-1.34) per 5 years for right colon, left colon and rectal cancer, respectively] and the risk of left colon cancer increased with higher body mass index [HR 1.28 (1.12-1.46) per 5 kg/m² ]. The risk of right colon cancer (RCC) increased with smoking [HR 1.07 (1.04-1.10) per 5 pack years]. Among women, the risk of cancer at all locations increased with age [HR 1.38 (1.34-1.43), HR 1.23 (1.19-1.27), HR 1.20 (1.16-1.24) per 5 years] and smoking [HR 1.07 (1.02-1.12), HR 1.07 (1.02-1.12), HR 1.10 (1.05-1.17) per 5 pack years] for right colon, left colon and rectal cancer, respectively. The risk of RCC increased with night shift work [HR 1.93 (1.22-3.05)].

CONCLUSION

The risk factors for developing CRC differ by anatomical location and sex. The relationship between risk factors and CRC may be more nuanced than previously known.

Diagnosis by Volatile Organic Compounds in Exhaled Breath in Exhaled Breath from Patients with Gastric and Colorectal Cancers

One in three cancer deaths worldwide are caused by gastric and colorectal cancer malignancies. Although the incidence and fatality rates differ significantly from country to country, the rates of these cancers in East Asian nations such as South Korea and Japan have been increasing each year. Above all, the biggest danger of this disease is how challenging it is to recognize in its early stages. Moreover, most patients with these cancers do not present with any disease symptoms before receiving a definitive diagnosis. Currently, volatile organic compounds (VOCs) are being used for the early prediction of several other diseases, and research has been carried out on these applications. Exhaled VOCs from patients possess remarkable potential as novel biomarkers, and their analysis could be transformative in the prevention and early diagnosis of colon and stomach cancers. VOCs have been spotlighted in recent studies due to their ease of use. Diagnosis on the basis of patient VOC analysis takes less time than methods using gas chromatography, and results in the literature demonstrate that it is possible to determine whether a patient has certain diseases by using organic compounds in their breath as indicators. This study describes how VOCs can be used to precisely detect cancers; as more data are accumulated, the accuracy of this method will increase, and it can be applied in more fields.

Intracellular and extracellular factors of colorectal cancer liver metastasis: a pivotal perplex to be fully elucidated

Metastasis is the leading cause of death in colorectal cancer (CRC) patients, and the liver is the most common site of metastasis. Tumor cell metastasis can be thought of as an invasion-metastasis cascade and metastatic organotropism is thought to be a process that relies on the intrinsic properties of tumor cells and their interactions with molecules and cells in the microenvironment. Many studies have provided new insights into the molecular mechanism and contributing factors involved in CRC liver metastasis for a better understanding of the organ-specific metastasis process. The purpose of this review is to summarize the theories that explain CRC liver metastasis at multiple molecular dimensions (including genetic and non-genetic factors), as well as the main factors that cause CRC liver metastasis. Many findings suggest that metastasis may occur earlier than expected and with specific organ-anchoring property. The emergence of potential metastatic clones, the timing of dissemination, and the distinct routes of metastasis have been explained by genomic studies. The main force of CRC liver metastasis is also thought to be epigenetic alterations and dynamic phenotypic traits. Furthermore, we review key extrinsic factors that influence CRC cell metastasis and liver tropisms, such as pre-niches, tumor stromal cells, adhesion molecules, and immune/inflammatory responses in the tumor microenvironment. In addition, biomarkers associated with early diagnosis, prognosis, and recurrence of liver metastasis from CRC are summarized to enlighten potential clinical practice, including some markers that can be used as therapeutic targets to provide new perspectives for the treatment strategies of CRC liver metastasis.

Clinicopathological features and prognosis of colonic and rectal gastrointestinal stromal tumors: A propensity score matching analysis

Background

Colonic gastrointestinal stromal tumor (cGIST) and rectal gastrointestinal stromal tumor (rGIST) are two rare subtypes of gastrointestinal stromal tumor (GIST). The view that colonic and rectal carcinoma are different is generally accepted; however, whether there is a difference between cGIST and rGIST is still unknown. Here, we aimed to provide evidence for future clinical management and research by comparing the differences between the two types of GIST in the above-mentioned aspects.

Methods

Patients were enrolled from three medical centers in China and published literature was collected following the inclusion and exclusion criteria. Propensity score matching was used to eliminate differences between cohorts.

Results

Between cGIST and rGIST patients, significant differences were observed in age, tumor size, mitotic index, NIH risk category, growth pattern, and symptoms. Adjuvant therapy is used in a high proportion of cGIST patients, and neoadjuvant therapy is used in a high proportion of rGIST patients. Although local resection is the main surgical method in both cohorts, the proportion is higher in cGIST patients. The overall survival of rGIST patients was better than that of the cGIST patients before propensity score matching (PSM). Interestingly, no significant differences in prognosis were observed after PSM.

Conclusions

Although there were significant differences between cGIST and rGIST patients in baseline characteristics, clinicopathological features, treatment choice, and overall survival rate before PSM, no significant differences in long-term survival were observed between the two groups after PSM. In our study, there may be no differences in the tumor entity between cGIST and rGIST.

Fucosyltransferase 4 Predicts Patient Outcome in Rectal Cancer through an Immune Microenvironment-Mediated Multi-Mechanism

Colorectal cancer is the most common type of gastrointestinal malignant tumors worldwide. Standardization of the strategy for the precise treatment of this cancer has been a major challenge. Enrichment analysis of six gene groups (colon cancer-specific genes (upregulated and downregulated); rectal cancer-specific genes (upregulated and downregulated); and common genes (upregulated and downregulated)) revealed the common and specific features of colon and rectal cancer, particularly a hyperactive immune response in rectal cancer. Key common genes exhibited a similar expression pattern, but were associated with distinct patient prognosis in colon and rectal cancer. FUT4 was a core regulatory gene in rectal cancer; it can decrease the level of infiltration by M2 macrophages in the tumor immune microenvironment and participate in the positive regulation of the immune system and glycoprotein biosynthetic process, thereby affecting the outcome of patients with rectal cancer. FUT4 co-expression genes can influence patient’s survival time by regulating the cell cycle. Among the regulators of FUT4 co-expression genes, checkpoint kinase 2 (CHEK2) was linked to patient outcome.

The Association of Metformin, Other Antidiabetic Medications and Statins on the Prognosis of Rectal Cancer in Patients with Type 2 Diabetes: A Retrospective Cohort Study

Metformin and statin use have been associated with an improved prognosis for colorectal cancer in persons with type 2 diabetes (T2D). Data regarding rectal cancer (RC) have been inconclusive; therefore, we investigated the issue with high-quality data and a robust study design. We identified 1271 eligible patients with T2D and incident RC between 1998 and 2011 from the Diabetes in Finland (FinDM) database. Cox models were fitted for cause-specific mortality rates to obtain adjusted estimates of the hazard ratios (HR) with 95% confidence intervals (CI) in relation to use of antidiabetic medication (ADM) and statins before the RC diagnosis and for post-diagnostic use in a time-dependent exposure manner. No sufficient evidence was found for either pre- or post-diagnostic metformin use and RC mortality (HR 0.96, 95% CI 0.67–1.38, and 0.70, 95% CI 0.45–1.10, respectively) when compared to other oral ADMs. Both pre- and post-diagnostic statin use appeared to be inversely associated with mortality from RC (HR 0.77 95% CI 0.63–0.94, and 0.57, 95% CI 0.42–0.78, respectively). Our study was inconclusive as to the association of metformin use with the prognosis of RC, but statin use was found to predict reduced mortality, both from RC and from other causes of death in persons with T2D.

SNAI1-expressing fibroblasts and derived-extracellular matrix as mediators of drug resistance in colorectal cancer patients

Resistance to antitumor treatments is one of the most important problems faced by clinicians in the management of colorectal cancer (CRC) patients. Cancer-Associated Fibroblasts (CAFs) are the main producers and remodelers of the extracellular matrix (ECM), which is directly involved in drug resistance mechanisms. Primary Normal Fibroblasts (NFs) and CAFs and cell lines (fibroblasts and tumor cells), were used to generate ECM and to identify its role in the oxaliplatin and cetuximab chemoresistance processes of CRC cells mediated by SNAI1-expressing fibroblasts. Matrices generated by Snai1 KO MEFs (Knockout Mouse Embryonic Fibroblasts) confer less resistance on oxaliplatin and cetuximab than wild-type MEF-derived matrices. Similarly, matrices derived from CAFs cause greater survival of colorectal cancer cells than NF-derived matrices, in a similar way to Snai1 expression levels. In addition, Snail1 expression in fibroblasts regulates drug resistance and metabolism gene expression in tumor cells mediated by ECM. Finally, a series of 531 patients (TCGA) with CRC was used to assess the role of SNAI1 expression in patients' prognosis indicating an association between tumor SNAI1 expression and overall survival in colon cancer patients but not in rectal cancer patients. SNAI1 expression in CRC cancer patients, together with in vitro experimentation, suggests the possible use of SNAI1 expression in tumor-associated fibroblasts as a predictive biomarker of response to oxaliplatin and cetuximab treatments in patients with CRC.

Prognostic Impact of TP53 Mutations and Tumor Mutational Load in Colorectal Cancer

The DNA damage response (DDR) is critical for maintaining genome stability, and abnormal DDR—resulting from mutations in DNA damage-sensing and repair proteins—is a hallmark of cancer. Here, we aimed to investigate the predictive power of DDR gene mutations and the tumor mutational load (TML) for survival outcomes in a cohort of 22 rectal cancer patients who received pre-operative neoadjuvant therapy. Univariate analysis revealed that TML-high and TP53 mutations were significantly associated with worse overall survival (OS) with TML-high retaining significance in multivariate analyses. Kaplan–Meier survival analyses further showed TML-high was associated with worse disease-free (p = 0.036) and OS (p = 0.024) results in our patient cohort. A total of 53 somatic mutations were identified in 22 samples with eight (36%) containing mutations in DDR genes, including ATM, ATR, CHEK2, MRE11A, RAD50, NBN, ERCC2 and TP53. TP53 was the most frequently mutated gene, and TP53 mutations were significantly associated with worse OS (p = 0.023) in Kaplan–Meier survival analyses. Thus, our data indicate that TML and TP53 mutations have prognostic value for rectal cancer patients and may be important independent biomarkers for patient management. This suggests that prognostic determination for rectal cancer patients receiving pre-operative neoadjuvant therapy should include consideration of the initial TML and tumor genetic status.

TRIM29 is differentially expressed in colorectal cancers of different primary locations and affects survival by regulating tumor immunity based on retrospective study and bioinformatics analysis

Background

In colorectal cancer (CRC) patients, different primary tumor locations caused distinct prognosis and clinicopathological features. It is necessary to identify specific tumor markers according tumor site. Our previous work has identified differentially expressed genes between CRC and adjacent normal tissues, in which only TRIM29 was differently expressed between right colon cancer (RCC) and left colon cancer (LCC) patients. Rectal cancer (RECC) was not included in this latter study and the effects of TRIM29 on the survival with RCC and LCC patients were not investigated. This study further verified TRIM29 expression through Gene Expression Omnibus (GEO) database and our retrospective study. The role of TRIM29 on survival according tumor sites was also explored. Furthermore, the molecular mechanisms of TRIM29 were explored.

Methods

The GEO dataset was used to confirm the differential expression of TRIM29 in proximal and distal cancers. Moreover, TRIM29 were assess using immunohistochemistry (IHC) in 227 cases to observe the correlation between TRIM29 and tumor site. The relationship between TRIM29 and the clinicopathologic features was investigated according tumor sites. Furthermore, the disease-free survival (DFS) and overall survival (OS) was analyzed using the Kaplan-Meier method to assess the prognostic value of TRIM29. Finally, bioinformatics analysis was used to explore the molecular mechanisms. The Tumor-Immune System Interactions and Drug Bank database (TISIDB) was used to analyze the correlations between TRIM29 expression and tumor immune functions. The correlation of TRIM29 with tumor infiltrating lymphocytes or mismatch-repair-proficient/mismatch-repair-deficient (pMMR/dMMR) status was also investigated.

Results

TRIM29 expression was significantly higher in patients with RCC (P<0.001). RCC patients with high TRIM29 tended to be older, male, in stage III-IV, with N+ staging, and intestinal obstruction (P<0.001, P<0.001, P<0.001, P<0.001, and P=0.010, respectively). High TRIM29 expression was associated with an increased risk of recurrence/metastasis and death, only in RCC patients (P=0.020 and P<0.001). Functional annotations and immune activity analysis showed that TRIM29 is related to tumor infiltrating lymphocytes and immune dysfunction.

Conclusions

TRIM29 plays varying roles in patients with different tumor sites. TRIM29 is correlated with the clinicopathological features and prognosis in RCC patients. Indeed, TRIM29 may serve as a new biomarker for RCC patients.