Perineural Invasion is a Strong Prognostic Factor in Colorectal Cancer: A Systematic Review.Am J Surg Pathol. 2016;40:103-112. [PMID: 26426380 DOI: 10.1097/PAS.0000000000000518]

Rare Case of Additional Ileocecal Resection for Ascending Colon Cancer with R1 Resection due to Advanced Perineural Invasion

INTRODUCTION

Perineural invasion (PNI) has been cited as an independent prognostic factor in colorectal cancer. We report the first case of an additional resection after ileocecal resection due to advanced lateral extension of PNI, with a review of the literature.

CASE PRESENTATION

A 67-year-old woman underwent colonoscopy due to positive fecal occult blood. Biopsy revealed a 20-mm type 2 tumor in the ascending colon near the ileocecal valve, which was a poorly differentiated adenocarcinoma. She underwent laparoscopic-assisted ileocecal resection and D3 dissection, and the surgery was completed routinely in which functional end-to-end anastomosis (FEEA) was performed extracorporeally. Postoperative course was good and she was discharged one week postoperatively. The pathology showed AI, type 3, 30 × 23 mm, 40%, por2>sig>tub2, pT3a (SS), int, INFb, v2, ly3, Pn1b, PM1, DM0, pN1. There was widespread cancerous extension along the intermuscular plexus within the intrinsic muscular layer of the ileum, and although grossly separated from the tumor by about 80 mm, the tumor was R1 resected with positive oral margins. Additional anastomotic resection was performed by laparotomy. Intraoperatively, the resected section was submitted to a rapid examination, which was confirmed to be negative, and the surgery was completed. The pathological examination revealed that the resected specimen showed an adenocarcinoma on the ileum side of the anastomosis, which infiltrated and proliferated within the intermuscular plexus by about 15 mm, although the tumor was not visually recognized on the resection specimen. Both bilateral margins were negative, resulting in R0 resection. Postoperative adjuvant chemotherapy was not requested by the patient. Thereafter, periodic imaging follow-up was performed and, nine months after the initial diagnosis, there was no increase in tumor markers and no evidence of recurrence on imaging.

CONCLUSIONS

Preventing R1 resection due to lateral extension of advanced PNI, which is very rare as in this case, is practically difficult given its frequency and residual bowel function. Instead, prompt additional resection and adjuvant therapy (which was not performed in this case) are essential to minimize the risk of recurrence.

Risk score model for predicting local control and survival in patients with rectal cancer treated with neoadjuvant chemoradiotherapy

The present study aimed to investigate clinicopathological factors affecting local recurrence and survival in patients with locally advanced rectal cancer (LARC) treated with neoadjuvant chemoradiotherapy (nCRT) and to create a risk-scoring model predicting local control (LC) and survival. The clinical and pathological data of 115 patients who received nCRT for LARC between February 2010 and December 2020 were reviewed retrospectively. A risk-scoring model was developed to predict LC and survival using statistically significant prognostic factors in univariate and multivariate analyses. In the multivariate analysis, the LC rate was improved in patients with a good pathological response to nCRT. By contrast, the disease-free survival (DFS) rate was significantly worse in patients with perineural invasion (PNI). The overall survival (OS) rate was significantly worse in patients who were >60 years of age, who had tumors ≥5 cm, who were PNI-positive and who had pathological N2 stage disease. Patients were grouped to analyze the ability of the scoring system to predict LC and survival. The total score was derived by assigning points to the prognostic factors in univariate and multivariate analyses and was subsequently divided into three groups according to tertile. The median LC times in groups 1-3 were significantly different at 143.6, 97.2 and 93.6 months, respectively. The median DFS times in groups 1-3 were significantly different at 136.1, 108.5 and 67.2 months, respectively, while the median OS times in groups 1-3 were significantly different at 138.3, 87.2 and 64.6 months, respectively. In conclusion, risk score modeling with prognostic factors effectively determined the difference in LC and survival between the groups. Adding effective systemic therapy to nCRT may improve results, especially in patients with multiple poor prognostic factors, including larger tumors, PNI and multiple nodal involvement.

Predictive Study of Machine Learning-Based Multiparametric MRI Radiomics Nomogram for Perineural Invasion in Rectal Cancer: A Pilot Study

This study aimed to establish and validate the efficacy of a nomogram model, synthesized through the integration of multi-parametric magnetic resonance radiomics and clinical risk factors, for forecasting perineural invasion in rectal cancer. We retrospectively collected data from 108 patients with pathologically confirmed rectal adenocarcinoma who underwent preoperative multiparametric MRI at the First Affiliated Hospital of Bengbu Medical College between April 2019 and August 2023. This dataset was subsequently divided into training and validation sets following a ratio of 7:3. Both univariate and multivariate logistic regression analyses were implemented to identify independent clinical risk factors associated with perineural invasion (PNI) in rectal cancer. We manually delineated the region of interest (ROI) layer-by-layer on T2-weighted imaging (T2WI) and diffusion-weighted imaging (DWI) sequences and extracted the image features. Five machine learning algorithms were used to construct radiomics model with the features selected by least absolute shrinkage and selection operator (LASSO) method. The optimal radiomics model was then selected and combined with clinical features to formulate a nomogram model. The model performance was evaluated using receiver operating characteristic (ROC) curve analysis, and its clinical value was assessed via decision curve analysis (DCA). Our final selection comprised 10 optimal radiological features and the SVM model showcased superior predictive efficiency and robustness among the five classifiers. The area under the curve (AUC) values of the nomogram model were 0.945 (0.899, 0.991) and 0.846 (0.703, 0.99) for the training and validation sets, respectively. The nomogram model developed in this study exhibited excellent predictive performance in foretelling PNI of rectal cancer, thereby offering valuable guidance for clinical decision-making. The nomogram could predict the perineural invasion status of rectal cancer in early stage.

Dose Escalation in Neoadjuvant Chemoradiotherapy for Rectal Cancer: Short-Term Efficacy and Toxicity of VMAT-SIB vs. 3D-CRT

Background and Objectives: The standard treatment for locally advanced rectal cancer (LARC) includes neoadjuvant chemoradiotherapy (nCRT), followed by surgery with or without adjuvant chemotherapy (CT). This study evaluated the efficacy and safety of dose-escalated radiotherapy (RT) using the volumetric modulated arc therapy-simultaneous integrated boost (VMAT-SIB) technique in patients with LARC compared to 3D conformal radiotherapy (3D-CRT). Materials and Methods: This study prospectively enrolled 75 patients with LARC. All patients received nCRT using VMAT-SIB, delivering a tumor dose (TD) of 54 Gy in 25 fractions, with concomitant CT following the 5-fluorouracil and leucovorin (5-FU-LV) protocol. To compare the treatment outcomes and toxicity associated with the increased RT dose, a retrospective cohort of 62 patients treated with the 3D-CRT technique was analyzed. The 3D-CRT group received a TD of 50.4 Gy in 28 fractions with the same CT. Outcomes, including pathological complete response (pCR), tumor regression grade (TRG), and sphincter preservation rates, were compared. Results: Among operated patients, the group treated with VMAT-SIB demonstrated improved rates of pCR (20.6% vs. 8.9%), with a statistically significant trend (p = 0.06). Sphincter-preserving surgeries were performed in 49 out of 63 operated patients (77.8%) in the VMAT-SIB group, compared to 35 out of 56 (62.5%) in the 3D-CRT group. Analysis of the definitive postoperative stage revealed a significantly higher prevalence of lower T categories (T0-2) (p < 0.01), negative N status (p < 0.05), and lower stages (I + II) (p < 0.05) in patients treated with the intensified RT approach. However, no significant differences in acute toxicity were observed. Conclusions: The implementation of intensified treatment with a higher dose using the VMAT-SIB technique demonstrated significant benefits in downsizing and downstaging compared to the standard treatment approach. These findings support its integration into clinical practice. However, further prospective, multi-center studies are needed to validate these results and assess long-term outcomes.

Important role of lymphovascular and perineural invasion in prognosis of colorectal cancer patients with N1c disease

BACKGROUND

Lymphovascular invasion (LVI) and perineural invasion (PNI) are associated with decreased survival in colorectal cancer (CRC), but its significance in N1c stage remains to be clearly defined.

AIM

To evaluate LVI and PNI as potential prognostic indicators in N1c CRC.

METHODS

We retrospectively identified 107 consecutive patients who had CRC with N1c disease radically resected at our hospital. Tumors were reviewed for LVI and PNI by one pathologist blinded to the patients' outcomes. Disease-free survival (DFS), overall survival (OS) and cancer-specific survival (CSS) were determined using the Kaplan-Meier method, with LVI and PNI prognosis differences determined by multivariate analysis using the Cox multiple hazards model. Results were compared using log-rank test. The receiver operating characteristic (ROC) curve was used to evaluate the prognostic predictive ability.

RESULTS

The median follow-up time was 63.17 (45.33-81.37) months for DFS, with 33.64% (36/107) of patients experiencing recurrence; 21.5% of tumors were found to be LVI positive and 44.9% PNI positive. The 5-year DFS rate was greater for patients with LVI-negative tumors compared with LVI-positive tumors (74.0% vs 35.6%), and PNI was similar (82.5% vs 45.1%). On multivariate analysis, LVI [hazard ratio (HR) = 3.368, 95% confidence interval (CI): 1.628-6.966, P = 0.001] and PNI (HR = 3.055, 95%CI: 1.478-6.313, P = 0.002) were independent prognostic factors for DFS. All patients could be divided into three groups of patients with different prognosis according to LVI and PNI. The 5-year ROC curve for LVI, PNI and their combination prediction of DFS was 0.646, 0.709 and 0.759, respectively. Similar results were seen for OS and CSS.

CONCLUSION

LVI and PNI could serve as independent prognostic factors of outcomes in N1c CRC patients. Patients with LVI or PNI should be given more attention during treatment.

Association between lymphovascular invasion and lymph node metastases in colon cancer: A National Cancer Database analysis

AIM

Lymphovascular invasion (LVI) is a well-known risk factor in colorectal cancer that is associated with a worse prognosis. The present study aimed to assess the characteristics of patients with LVI-positive colon cancer according to the status of nodal metastases and to study the association between LVI-nodal status and survival.

METHOD

This retrospective study assessed the association between LVI and lymph node metastases in colon cancer, using data from the National Cancer Database. Patients were classified according to the pathological N stage into pN0 and pN1-2. The risk factors for LVI were determined in each group using multivariable regression analyses. The primary outcome was LVI and the secondary outcome was 5-year overall survival (OS). A modification of the tumour, node, metastasis (TNM) staging system that incorporates LVI in each stage was proposed.

RESULTS

The study included 357 724 patients (51.1% female, median age 70 years). LVI was detected in 11.6% and 52.5% of patients with node-negative and node-positive disease, respectively. The independent predictors of LVI in pN0 stage were poorly differentiated carcinomas (OR: 3.6, p < 0.001), undifferentiated carcinomas (OR: 3.3, p < 0.001), mucinous carcinomas (OR: 0.61, p < 0.001), and perineural invasion (OR: 4.2, p < 0.001). The independent predictors of LVI in pN1-2 disease were poorly differentiated carcinomas (OR: 2.36, p < 0.001), undifferentiated carcinomas (OR: 3.23, p < 0.001), and perineural invasion (OR: 3.33, p < 0.001). LVI was significantly associated with worse 5-year OS and the adverse survival impact of LVI was higher in pN1-2 disease (HR: 1.47, p < 0.001) than in pN0 disease (HR: 1.28, p < 0.001). When LVI was present, the 5-year OS was reduced by 1.5% in stage I, 5.6% in stage II, and 11.5% in stage III.

CONCLUSION

LVI was more prevalent in patients with colon cancer with lymph node metastases than in patients with node-negative disease. However, LVI was not detected in approximately half of patients with nodal disease. The adverse survival effect of LVI was proportional to the stage of colon cancer.

Comparative analysis of the oncologic outcomes and risk factors for open conversion in laparoscopic surgery for non-metastatic colorectal cancer: A retrospective multicenter study

PURPOSE

Laparoscopic colon surgery is now commonly used for colorectal cancer (CRC) resection. The objective of this study was to compare the oncologic outcomes between open conversion and laparoscopic surgery, and to identify risk factors for open conversion.

METHODS

We retrospectively reviewed the medical records of patients who underwent curative resection for stage 0-III CRC at five Hallym University-affiliated hospitals between January 2011 and June 2021. The patients were divided into the conversion and laparoscopic groups according to whether laparoscopic surgery was completed.

RESULTS

Out of 2231 patients, laparoscopic surgery was completed in 2131 patients and 100 (4.5 %) converted to open surgery. The operation time (P = 0.028) and postoperative hospital stay (P = 0.036) were longer in the conversion group than in the laparoscopic group. Overall (P = 0.022) and severe (Clavien-Dindo classification grade ≥3) (P = 0.048) complications were more frequent in the conversion group than in the laparoscopic group. The 5-year recurrence-free survival (RFS) rate was worse in the conversion group than in the laparoscopic group (P = 0.002). In the multivariable analysis, open conversion was not a prognostic factor for RFS (P = 0.082). Abdominal surgery history (P = 0.021), obstruction (P < 0.001), and T4 stage (P < 0.001) were independently associated with open conversion.

CONCLUSION

The conversion group had worse perioperative and oncologic outcomes. History of abdominal surgery, obstruction, and T4 stage were associated with open conversion. However, conversion itself was not associated with RFS.

Risk factors for recurrence in stage I colorectal cancer after curative resection: a systematic review and meta-analysis

Purpose

Patients with stage I colorectal cancer (CRC) rarely experience recurrence after curative resection. Therefore, the risk factors for stage I CRC recurrence are yet to be established. We aimed to identify risk factors for stage I CRC recurrence.

Methods

MEDLINE, Embase, and Cochrane Library were searched for articles published between 1990 and 2022. The pooled proportions and hazard ratios (HRs) were calculated. Fixed- or random-effect models were considered based on heterogeneity, using Cochran's Q-statistic and the I2-test.

Results

Nine studies involving 19,440 patients were included. Nine analyzed risk factors were identified. T2 stage (pooled HR, 2.070; 95% confidence interval [CI], 1.758-2.438; P < 0.001; I2=0.0%), lymphovascular invasion (HR, 1.685; 95% CI, 1.420-1.999; P < 0.001; I2 = 0.0%), venous invasion (HR, 1.794; 95% CI, 1.515-2.125; P < 0.001; I2 = 0.0%), CEA level (HR, 1.472; 95% CI, 1.093-1.983; P = 0.011; I2 = 1.8%) and rectal cancer (HR, 2.981; 95% CI, 2.378-3.735; P < 0.001; I2 = 0.0%) were risk factors for the recurrence. However, the risk of recurrence in right-sided colon cancer was lower than in left-sided colon cancer. (HR, 0.712; 95% CI, 0.537-0.944; P = 0.018; I2 = 0.0%). No statistically significant differences were observed in the number of harvested lymph nodes, age, and sex.

Conclusion

T2 stage, lymphovascular invasion, venous invasion, CEA level, rectal cancer, and left-sided colon cancer were risk factors for recurrence in stage I CRC. Intensive monitoring and surveillance are warranted for patients with high-risk features of recurrence.

Prognostic prediction models for postoperative patients with stage I to III colorectal cancer based on machine learning

BACKGROUND

Colorectal cancer (CRC) is characterized by high heterogeneity, aggressiveness, and high morbidity and mortality rates. With machine learning (ML) algorithms, patient, tumor, and treatment features can be used to develop and validate models for predicting survival. In addition, important variables can be screened and different applications can be provided that could serve as vital references when making clinical decisions and potentially improving patient outcomes in clinical settings.

AIM

To construct prognostic prediction models and screen important variables for patients with stage I to III CRC.

METHODS

More than 1000 postoperative CRC patients were grouped according to survival time (with cutoff values of 3 years and 5 years) and assigned to training and testing cohorts (7:3). For each 3-category survival time, predictions were made by 4 ML algorithms (all-variable and important variable-only datasets), each of which was validated via 5-fold cross-validation and bootstrap validation. Important variables were screened with multivariable regression methods. Model performance was evaluated and compared before and after variable screening with the area under the curve (AUC). SHapley Additive exPlanations (SHAP) further demonstrated the impact of important variables on model decision-making. Nomograms were constructed for practical model application.

RESULTS

Our ML models performed well; the model performance before and after important parameter identification was consistent, and variable screening was effective. The highest pre- and postscreening model AUCs 95% confidence intervals in the testing set were 0.87 (0.81-0.92) and 0.89 (0.84-0.93) for overall survival, 0.75 (0.69-0.82) and 0.73 (0.64-0.81) for disease-free survival, 0.95 (0.88-1.00) and 0.88 (0.75-0.97) for recurrence-free survival, and 0.76 (0.47-0.95) and 0.80 (0.53-0.94) for distant metastasis-free survival. Repeated cross-validation and bootstrap validation were performed in both the training and testing datasets. The SHAP values of the important variables were consistent with the clinicopathological characteristics of patients with tumors. The nomograms were created.

CONCLUSION

We constructed a comprehensive, high-accuracy, important variable-based ML architecture for predicting the 3-category survival times. This architecture could serve as a vital reference for managing CRC patients.

Impact of self-expanding metal stents on long-term survival outcomes as a bridge to surgery in patients with colon cancer obstruction: Current state and future prospects

Since self-expanding metal stents (SEMS) were first introduced in acute colon cancer obstruction, the increased rate of primary anastomosis and improved quality of life following SEMS placement have been clearly shown. However, it was demonstrated that SEMS are associated with higher recurrence rates. Although several trials have shown that overall and disease-free survival in patients following SEMS placement is similar with patients undergoing emergency surgery, obstruction and a high incidence of recurrence imposed many concerns. The optimal time interval from SEMS to surgery is still a matter of debate. Some studies have recommended a time interval of ~2 weeks between SEMS insertion and elective surgery. A prolonged interval of time from SEMS insertion to elective surgery and the administration of neoadjuvant chemotherapy (NAC) has been proposed. SEMS-NAC might have advantages for improving the surgical and long-term survival outcomes of patients with acute colon cancer obstruction, which is an optional approach in the management of acute colon cancer obstruction.

Constructing a prognostic model for colorectal cancer with synchronous liver metastases after preoperative chemotherapy: a study based on SEER and an external validation cohort

BACKGROUND

The combination of preoperative chemotherapy and surgical treatment has been shown to significantly enhance the prognosis of colorectal cancer with liver metastases (CRLM) patients. Nevertheless, as a result of variations in clinicopathological parameters, the prognosis of this particular group of patients differs considerably. This study aimed to develop and evaluate Cox proportional risk regression model and competing risk regression model using two patient cohorts. The goal was to provide a more precise and personalized prognostic evaluation system.

METHODS

We collected information on individuals who had a pathological diagnosis of colorectal cancer between 2000 and 2019 from the Surveillance, Epidemiology, and End Results (SEER) Database. We obtained data from patients who underwent pathological diagnosis of colorectal cancer and got comprehensive therapy at the hospital between January 1, 2010, and June 1, 2022. The SEER data collected after screening according to the inclusion and exclusion criteria were separated into two cohorts: a training cohort (training cohort) and an internal validation cohort (internal validation cohort), using a random 1:1 split. Subgroup Kaplan-Meier (K-M) survival analyses were conducted on each of the three groups. The data that received following screening from the hospital were designated as the external validation cohort. The subsequent variables were chosen for additional examination: age, gender, marital status, race, tumor site, pretreatment carcinoembryonic antigen level, tumor size, T stage, N stage, pathological grade, number of tumor deposits, perineural invasion, number of regional lymph nodes examined, and number of positive regional lymph nodes. The primary endpoint was median overall survival (mOS). In the training cohort, we conducted univariate Cox regression analysis and utilized a stepwise regression approach, employing the Akaike information criterion (AIC) to select variables and create Cox proportional risk regression models. We evaluated the accuracy of the model using calibration curve, receiver operating characteristic curve (ROC), and area under curve (AUC). The effectiveness of the models was assessed using decision curve analysis (DCA). To evaluate the non-cancer-related outcomes, we analyzed variables that had significant impacts using subgroup cumulative incidence function (CIF) and Gray's test. These analyses were used to create competing risk regression models. Nomograms of the two models were constructed separately and prognostic predictions were made for the same patients in SEER database.

RESULTS

This study comprised a total of 735 individuals. The mOS of the training cohort, internal validation cohort, and QDU cohort was 55.00 months (95%CI 46.97-63.03), 48.00 months (95%CI 40.65-55.35), and 68.00 months (95%CI 54.91-81.08), respectively. The multivariate Cox regression analysis revealed that age, N stage, presence of perineural infiltration, number of tumor deposits and number of positive regional lymph nodes were identified as independent prognostic risk variables (p < 0.05). In comparison to the conventional TNM staging model, the Cox proportional risk regression model exhibited a higher C-index. After controlling for competing risk events, age, N stage, presence of perineural infiltration, number of tumor deposits, number of regional lymph nodes examined, and number of positive regional lymph nodes were independent predictors of the risk of cancer-specific mortality (p < 0.05).

CONCLUSION

We have developed a prognostic model to predict the survival of patients with synchronous CRLM who undergo preoperative chemotherapy and surgery. This model has been tested internally and externally, confirming its accuracy and reliability.

Localized Rectal Cancer: Indian Consensus and Guidelines

The rising incidence of colorectal cancer (CRC) in India, particularly the prevalence of rectal cancer over colon cancer (0.7:1), has been a growing concern in recent decades; especially notable is the trend of increasing cases among young CRC patients. Given the diverse treatment approaches for rectal cancer globally and the varying economic capacities of patients in low to middle-income countries (LMICs) like India, it is essential to establish consensus guidelines that are specifically tailored to meet the needs of these patients. To achieve this, a panel comprising 30 eminent rectal cancer experts convened to conduct a comprehensive and impartial evaluation of existing practices and recent advancements in the field. Through meticulous scrutiny of published literature and a consensus-building process that involved voting on pertinent questions, the panel formulated management strategies. These recommendations are the result of a rigorous, evidence-based process and encapsulate the collective wisdom and judgment of leading authorities in the field.

Development and validation of a risk predictive nomogram for colon cancer-specific mortality: a competing risk model based on the SEER database

BACKGROUND

Utilizing the SEER database, we developed a competing risk model along with a nomogram designed for the early identification of colon cancer-specific mortality (CSM) risk.

METHODS

Clinical and pathological information, along with other significant data, were obtained from the SEER database. Patients were randomly divided into a training set and a validation set. We investigated the independent factors affecting CSM among colon cancer patients using univariate and multivariate analyses within a competing risk framework, ultimately developing a predictive tool for CSM in colon cancer.

RESULTS

Involving 40,261 individuals diagnosed with colon cancer, our study included 10,397 deaths directly due to the disease and an additional 5,828 from other causes. We used a competing risk model to predict cancer-specific mortality (CSM) in these patients. For the training dataset, the model's area under the curve (AUC) for predicting 1-, 3-, and 5-year cancer-specific survival (CSS) was 0.835 (95% confidence interval [CI] 0.826 to 0.844), 0.849 (95% CI 0.843 to 0.855), and 0.843 (95% CI 0.836 to 0.850), respectively. In the validation group, the AUC values for the same time periods were 0.846 (95% CI 0.833 to 0.860), 0.853 (95% CI 0.843 to 0.862), and 0.846 (95% CI 0.835 to 0.856), respectively. In comparison, traditional survival analysis yielded higher cumulative CSM rates over time than those provided by our competing risk approach.

CONCLUSION

We created a competitive risk assessment model along with a predictive tool designed to estimate CSM in patients with colon cancer. This nomogram demonstrates high accuracy and reliability, aiding medical professionals in making clinical decisions and developing patient follow-up plans.

Risk factors and treatment strategies for local recurrence of locally advanced rectal cancer treated with neoadjuvant chemoradiotherapy followed by total mesorectal excision

BACKGROUND

Despite advancements in total mesorectal excision (TME) and neoadjuvant radiotherapy, locally advanced rectal cancer remains challenging, impacting patient quality of life and mortality. This study aimed to identify the risk factors for local recurrence in locally advanced rectal cancer treated with neoadjuvant chemoradiotherapy (CRT) and assess treatment strategies for recurrence.

METHODS

This retrospective analysis included 682 patients diagnosed with locally advanced rectal cancer who were treated with neoadjuvant CRT and TME at Samsung Medical Center from 2008 to 2017. The exclusion criteria ensured a homogenous cohort. Clinical staging involved colonoscopies, computed tomography, magnetic resonance imaging, and digital rectal exam. Risk factors, treatment modalities, and oncological outcomes for local recurrence were evaluated.

RESULT

During a median 62-month follow-up, 47 patients (6.9 %) experienced local recurrence. The risk factors for local recurrence included a positive circumferential resection margin (CRM), venous invasion, and perineural invasion. Of the 47 patients with local recurrence, 25 (53.2 %) were considered resectable. Out of these, 23 patients underwent curative resections, and 15 (65.2 %) achieved R0 resection. Patients with R0 resections exhibited superior 5-year survival rates compared to R1-2 resection or non-surgical treatment, and there was no survival difference between R1-2 resection and non-surgical treatment.

CONCLUSION

In locally advanced rectal cancer, positive CRM, venous invasion, and perineural invasion were associated with local recurrence. R0 resection showed favorable outcomes, emphasizing the importance of surveillance in high-risk patients. Treatment decisions should consider these factors for improved oncologic outcomes and quality of life.

A radiomics model for predicting perineural invasion in stage II-III colon cancer based on computer tomography

BACKGROUND

Colon cancer, a frequently encountered malignancy, exhibits a comparatively poor survival prognosis. Perineural invasion (PNI), highly correlated with tumor progression and metastasis, is a substantial effective predictor of stage II-III colon cancer. Nonetheless, the lack of effective and facile predictive methodologies for detecting PNI prior operation in colon cancer remains a persistent challenge.

METHOD

Pre-operative computer tomography (CT) images and clinical data of patients diagnosed with stage II-III colon cancer between January 2015 and December 2023 were obtained from two sub-districts of Sun Yat-sen Memorial Hospital (SYSUMH). The LASSO/RF/PCA filters were used to screen radiomics features and LR/SVM models were utilized to construct radiomics model. A comprehensive model, shown as nomogram finally, combining with radiomics score and significant clinical features were developed and validated by area under the curve (AUC) and decision curve analysis (DCA).

RESULT

The total cohort, comprising 426 individuals, was randomly divided into a development cohort and a validation cohort as a 7:3 ratio. Radiomics scores were extracted from LASSO-SVM models with AUC of 0.898/0.726 in the development and validation cohorts, respectively. Significant clinical features (CA199, CA125, T-stage, and N-stage) were used to establish combining model with radiomics scores. The combined model exhibited superior reliability compared to single radiomics model in AUC value (0.792 vs. 0.726, p = 0.003) in validation cohorts. The radiomics-clinical model demonstrated an AUC of 0.918/0.792, a sensitivity of 0.907/0.813 and a specificity of 0.804/0.716 in the development and validation cohorts, respectively.

CONCLUSION

The study developed and validated a predictive nomogram model combining radiomics scores and clinical features, and showed good performance in predicting PNI pre-operation in stage II-III colon cancer patients.

The mode of circumferential margin involvement in rectal cancer determines its impact on outcomes: A population-based study

BACKGROUND

The clinical value of different modes of CRM involvement in rectal cancer patients is unclear. This study aims to determine the clinical impact of different modes of circumferential resection margin (CRM) involvement in patients with a locally advanced rectal carcinoma.

PATIENTS AND METHODS

A cohort of patients who were diagnosed with stage III rectal cancer between June 2014 and June 2020 was selected from the prospective Dutch nationwide pathology databank (PALGA). Histopathological and clinical data were analyzed according to the nature of CRM involvement (via primary tumor invasion, lymph node metastasis, tumor deposit, multiple factors) and analyses on recurrence and overall survival (OS) were performed.

RESULTS

3020 patients were included, of whom 12.4 % had a positive CRM. The majority of these patients (63.2 %) had CRM involvement by primary tumor invasion and in 9 % of patients multiple factors caused the positive CRM. The rates of local recurrence and distant metastasis were related to the nature of the CRM involvement, with lowest rate for lymph node metastasis and highest rate for multiple factors. On multivariate analysis, CRM involvement by primary tumor invasion, tumor deposits and multiple factors, but not by lymph node metastasis, were associated with poor OS.

CONCLUSION

This nationwide population based study highlights the clinical importance of reporting the nature of CRM involvement in rectal cancer patients. Lymph node metastasis involving the CRM does not bear the same risks for local recurrence, distant metastases and OS as CRM involvement by primary tumor invasion or CRM involvement by multiple factors.

Developing Individualized Follow-Up Strategies Based on High-Risk Recurrence Factors and Dynamic Risk Assessment for Locally Advanced Rectal Cancer

BACKGROUND

Locally advanced rectal cancer (LARC) is one of the most common malignant tumors worldwide, and its incidence is increasing year by year. Despite multimodal treatment, the recurrence rate of LARC patients remains high, about 20%-50%. However, the follow-up strategy according to tumor stage has certain limitations. There is no consensus on the optimal frequency and duration of follow-up. This study aims to comprehensively analyze the high-risk factors for recurrence in LARC from clinical characteristics, nutritional indicators, and imaging indexes. It intends to utilize conditional survival (CS) evaluation to assess dynamic survival and recurrence risks after comprehensive treatment of LARC and to develop individualized follow-up strategies.

METHODS

Logistic regression was utilized to analyze the independent recurrence factors in LARC patients. Calibration curve, decision curve, and ROC curve were employed to evaluate the model's efficacy. Kaplan-Meier curve was used to calculate CS rate and compare survival differences among different risk groups.

RESULTS

A total of 561 patients were analyzed in our study. Our multivariable logistic regression analysis revealed that the prognostic nutritional index (PNI), extramural vascular invasion (EMVI), vascular tumor thrombus, perineural invasion, and tumor size were independent factors for recurrence. Subsequently, a nomogram model was constructed and risk stratification was performed. Calibration curves and decision curves demonstrated that the model exhibited good clinical efficacy. The area under the ROC curve for the model was 0.763, indicating good sensitivity and specificity. Kaplan-Meier curves showed significant differences in survival among different risk groups. Furthermore, we observed that the CS without local recurrence and distant metastasis increased each year, while the cumulative recurrence risk decreased annually with prolonged survival time. Tailored follow-up intensities were developed for different risk groups and clinical stages based on the cumulative recurrence risk.

CONCLUSION

The personalized follow-up strategy based on risk stratification can optimize resource allocation, early detection of recurrence or metastasis, and ultimately enhance the overall care and prognosis of LARC patients.

Schwann cells and enteric glial cells: Emerging stars in colorectal cancer

Cancer neuroscience, a promising field dedicated to exploring interactions between cancer and the nervous system, has attracted growing attention. The gastrointestinal tracts exhibit extensive innervation, notably characterized by intrinsic innervation. The gut harbors a substantial population of glial cells, including Schwann cells wrapping axons of neurons in the peripheral nervous system and enteric glial cells intricately associated with intrinsic innervation. Glial cells play a crucial role in maintaining the physiological functions of the intestine, encompassing nutrient absorption, barrier integrity, and immune modulation. Nevertheless, it has only been in recent times that the significance of glial cells within colorectal cancer (CRC) has begun to receive considerable attention. Emerging data suggests that glial cells in the gut contribute to the progression and metastasis of CRC, by interacting with cancer cells, influencing inflammation, and modulating the tumor microenvironment. Here, we summarize the significant roles of glial cells in the development and progression of CRC and discuss the latest technologies that can be integrated into this field for in-depth exploration, as well as potential specific targeted strategies for future exploration to benefit patients.

Spectral CT in the evaluation of perineural invasion status in rectal cancer

PURPOSE

To investigate whether preoperative spectral CT quantitative parameters can assess perineural invasion (PNI) status in rectal cancer.

METHODS

Sixty-two patients diagnosed with rectal cancer who underwent preoperative spectral CT were retrospectively enrolled and divided into positive and negative PNI groups according to histopathologic results. The CT attenuation value (HU) of virtual monochromatic images (40-70 keV), spectral curve slope (K(HU)), effective atomic number (Zeff), and iodine concentration (IC) from spectral CT were compared between these two groups using t test or rank sum test. A nomogram was established by incorporating the independent predictors to assess the overall diagnostic efficacy. The area under the ROC curves (AUCs) were compared using the DeLong test.

RESULTS

The preoperative spectral CT parameters (40-70 keV attenuation, K(HU), Zeff, and IC) were significantly higher in the PNI-positive group compared to the PNI-negative group (all p < 0.05). The highest predictive efficiency of PNI was observed at 40 keV attenuation, with an area under the curve (AUC), sensitivity, specificity, and accuracy of 0.847, 81.8%, 72.5%, and 75.8%, respectively. Binary logistic regression demonstrated that the clinical feature (cN stage) and 40 keV attenuation were independent predictors of PNI status. The nomogram incorporating these two predictors (cN stage and 40 keV attenuation) exhibited the best evaluation efficacy, with an AUC, sensitivity, specificity, and accuracy of 0.885, 86.4%, 77.5%, and 80.6%.

CONCLUSION

Spectral CT quantitative parameters proved valuable in the preoperative assessment of PNI status in rectal cancer patients. The combination of spectral CT parameters and clinical features could further enhance the diagnostic efficiency.

The Glasgow Microenvironment Score: an exemplar of contemporary biomarker evolution in colorectal cancer

Colorectal cancer remains a leading cause of mortality worldwide. Significant variation in response to treatment and survival is evident among patients with similar stage disease. Molecular profiling has highlighted the heterogeneity of colorectal cancer but has had limited impact in daily clinical practice. Biomarkers with robust prognostic and therapeutic relevance are urgently required. Ideally, biomarkers would be derived from H&E sections used for routine pathological staging, have reliable sensitivity and specificity, and require minimal additional training. The biomarker targets would capture key pathological features with proven additive prognostic and clinical utility, such as the local inflammatory response and tumour microenvironment. The Glasgow Microenvironment Score (GMS), first described in 2014, combines assessment of peritumoural inflammation at the invasive margin with quantification of tumour stromal content. Using H&E sections, the Klintrup-Mäkinen (KM) grade is determined by qualitative morphological assessment of the peritumoural lymphocytic infiltrate at the invasive margin and tumour stroma percentage (TSP) calculated in a semi-quantitative manner as a percentage of stroma within the visible field. The resulting three prognostic categories have direct clinical relevance: GMS 0 denotes a tumour with a dense inflammatory infiltrate/high KM grade at the invasive margin and improved survival; GMS 1 represents weak inflammatory response and low TSP associated with intermediate survival; and GMS 2 tumours are typified by a weak inflammatory response, high TSP, and inferior survival. The prognostic capacity of the GMS has been widely validated while its potential to guide chemotherapy has been demonstrated in a large phase 3 trial cohort. Here, we detail its journey from conception through validation to clinical translation and outline the future for this promising and practical biomarker.

From diversity to disease: unravelling the role of enteric glial cells

Enteric glial cells (EGCs) are an essential component of the enteric nervous system (ENS) and play key roles in gastrointestinal development, homeostasis, and disease. Derived from neural crest cells, EGCs undergo complex differentiation processes regulated by various signalling pathways. Being among the most dynamic cells of the digestive system, EGCs react to cues in their surrounding microenvironment and communicate with various cell types and systems within the gut. Morphological studies and recent single cell RNA sequencing studies have unveiled heterogeneity among EGC populations with implications for regional functions and roles in diseases. In gastrointestinal disorders, including inflammatory bowel disease (IBD), infections and cancer, EGCs modulate neuroplasticity, immune responses and tumorigenesis. Recent evidence suggests that EGCs respond plastically to the microenvironmental cues, adapting their phenotype and functions in disease states and taking on a crucial role. They exhibit molecular abnormalities and alter communication with other intestinal cell types, underscoring their therapeutic potential as targets. This review delves into the multifaceted roles of EGCs, particularly emphasizing their interactions with various cell types in the gut and their significant contributions to gastrointestinal disorders. Understanding the complex roles of EGCs in gastrointestinal physiology and pathology will be crucial for the development of novel therapeutic strategies for gastrointestinal disorders.

The prognostic and predictive significance of perineural invasion in stage I to III colon cancer: a propensity score matching-based analysis

BACKGROUND

Colorectal cancer (CRC) presents with varying prognoses, and identifying factors for predicting metastasis and outcomes is crucial. Perineural invasion (PNI) is a debated prognostic factor for CRC, particularly in stage I-III patients, but its role in guiding adjuvant chemotherapy for node-positive colon cancer remains uncertain.

METHODS

We conducted a single-center study using data from the Colorectal Section Tumor Registry Database at Chang Gung Memorial Hospital, Taiwan. This prospective study involved 3,327 CRC patients, 1,536 of whom were eligible after application of the exclusion criteria, to investigate the prognostic value of PNI in stage I-III patients and its predictive value for node-positive/negative cancer patients receiving adjuvant chemotherapy. Propensity score matching (PSM) was used to minimize selection bias, and follow-up was performed with standardized procedures.

RESULTS

PNI-positive (PNI+) tumors were associated with higher preoperative CEA levels and more frequent adjuvant chemotherapy. After PSM, PNI + tumors were associated with marginally significantly lower 5-year disease-free survival (DFS) and significantly lower overall survival (OS) rates in stages III CRC. However, no significant differences were observed in stages I and II. Subgroup analysis showed that among PNI + tumors, only poorly differentiated tumors had higher odds of recurrence. PNI did not predict outcomes in node-negative colon cancer. Adjuvant chemotherapy benefited PNI + patients with node-positive but not those with node-negative disease.

CONCLUSIONS

Our study indicates that PNI is an independent poor prognostic factor in stage III colon cancer but does not predict outcomes in node-negative disease. Given the potential adverse effects of adjuvant chemotherapy, our findings discourage its use in node-negative colon cancer when PNI is present.

Pathological-Features-Modified TNM Staging System Improves Prognostic Accuracy for Rectal Cancer

BACKGROUND

Variations in survival outcomes are observed in the eighth edition of the American Joint Committee on Cancer TNM staging system.

OBJECTIVE

Machine learning ensemble methods were used to develop and evaluate the effectiveness of a pathological-features-modified TNM staging system in predicting survival for patients with rectal cancer by use of commonly reported pathological features, such as histological grade, tumor deposits, and perineural invasion, to improve the prognostic accuracy.

DESIGN

This was a retrospective population-based study.

SETTINGS

Data were assessed from the database of the Surveillance, Epidemiology, and End Results Program.

PATIENTS

The study cohort comprised 14,468 patients with rectal cancer diagnosed between 2010 and 2015. The development cohort included those who underwent surgery as the primary treatment, whereas patients who received neoadjuvant therapy were assigned to the validation cohort.

MAIN OUTCOME MEASURES

The primary outcome measures included cumulative rectal cancer survival, adjusted HRs, and both calibration and discrimination statistics to evaluate model performance and internal validation.

RESULTS

Multivariable Cox regression analysis identified all 3 pathological features as prognostic factors, after which patients were categorized into 4 pathological groups based on the number of pathological features (ie, 0, 1, 2, and 3). Distinct survival differences were observed among the groups, especially with patients with stage III rectal cancer. The proposed pathological-features-modified TNM staging outperformed the TNM staging in both the development and validation cohorts.

LIMITATIONS

Retrospective in design and lack of external validation.

CONCLUSIONS

The proposed pathological-features-modified TNM staging could complement the current TNM staging by improving the accuracy of survival estimation of patients with rectal cancer. See Video Abstract .

EL SISTEMA DE ESTADIFICACIN TNM CON CARACTERSTICAS PATOLGICAS MODIFICADO MEJORA LA PRECISIN DEL PRONSTICO DEL CNCER DE RECTO

ANTECEDENTES:Se observan variaciones en los resultados de supervivencia en el sistema de estadificación TNM del Comité Conjunto Americano del Cáncer 8º ediciónOBJETIVO:Se utilizaron métodos conjuntos de aprendizaje automático para desarrollar y evaluar la eficacia de un sistema de estadificación con características patológicas modificadas de tumores, ganglios y metástasis para predecir la supervivencia de pacientes con cáncer de recto, utilizando algunas características patológicas comúnmente informadas, como el grado histológico, depósitos tumorales e invasión perineural, para mejorar la precisión del pronóstico.DISEÑO:Este fue un estudio retrospectivo de base poblacional.ENTERNO CLINICO:Se recuperaron y evaluaron datos de la base de datos de Vigilancia, Epidemiología y Resultados Finales.PACIENTES:La cohorte del estudio estuvo compuesta por 14,468 pacientes con cáncer de recto diagnosticados entre 2010 y 2015. La cohorte de desarrollo incluyó a aquellos que se sometieron a cirugía como tratamiento primario, mientras que los pacientes que recibieron terapia neoadyuvante fueron asignados a la cohorte de validación.PRINCIPALES MEDIDAS DE RESULTADO:Las medidas de resultado primarias incluyeron supervivencia acumulada del cáncer de recto, índices de riesgo ajustados y estadísticas de calibración y discriminación para evaluar el rendimiento del modelo y la validación interna.RESULTADOS:El análisis de regresión multivariable de Cox identificó las tres características patológicas como factores pronósticos, después de lo cual los pacientes se clasificaron en cuatro grupos patológicos según el número de características patológicas (es decir, 0, 1, 2 y 3). Se observaron distintas diferencias en la supervivencia entre los grupos, especialmente en los pacientes en estadio III. La estadificación propuesta con características patológicas modificadas de tumores-ganglios-metástasis superó a la estadificación TNM tanto en las cohortes de desarrollo como en las de validación.LIMITACIONES:Diseño retrospectivo y falta de validación externa.CONCLUSIONES:La estadificación propuesta con características patológicas modificadas de tumores-ganglios-metástasis podría complementar la estadificación TNM actual al mejorar la precisión de la estimación de supervivencia de los pacientes con cáncer de recto. (Traducción- Dr. Francisco M. Abarca-Rendon ).

Preoperative prediction of perineural invasion of rectal cancer based on a magnetic resonance imaging radiomics model: A dual-center study

BACKGROUND

Perineural invasion (PNI) has been used as an important pathological indicator and independent prognostic factor for patients with rectal cancer (RC). Preoperative prediction of PNI status is helpful for individualized treatment of RC. Recently, several radiomics studies have been used to predict the PNI status in RC, demonstrating a good predictive effect, but the results lacked generalizability. The preoperative prediction of PNI status is still challenging and needs further study.

AIM

To establish and validate an optimal radiomics model for predicting PNI status preoperatively in RC patients.

METHODS

This retrospective study enrolled 244 postoperative patients with pathologically confirmed RC from two independent centers. The patients underwent pre-operative high-resolution magnetic resonance imaging (MRI) between May 2019 and August 2022. Quantitative radiomics features were extracted and selected from oblique axial T2-weighted imaging (T2WI) and contrast-enhanced T1WI (T1CE) sequences. The radiomics signatures were constructed using logistic regression analysis and the predictive potential of various sequences was compared (T2WI, T1CE and T2WI + T1CE fusion sequences). A clinical-radiomics (CR) model was established by combining the radiomics features and clinical risk factors. The internal and external validation groups were used to validate the proposed models. The area under the receiver operating characteristic curve (AUC), DeLong test, net reclassification improvement (NRI), integrated discrimination improvement (IDI), calibration curve, and decision curve analysis (DCA) were used to evaluate the model performance.

RESULTS

Among the radiomics models, the T2WI + T1CE fusion sequences model showed the best predictive performance, in the training and internal validation groups, the AUCs of the fusion sequence model were 0.839 [95% confidence interval (CI): 0.757-0.921] and 0.787 (95%CI: 0.650-0.923), which were higher than those of the T2WI and T1CE sequence models. The CR model constructed by combining clinical risk factors had the best predictive performance. In the training and internal and external validation groups, the AUCs of the CR model were 0.889 (95%CI: 0.824-0.954), 0.889 (95%CI: 0.803-0.976) and 0.894 (95%CI: 0.814-0.974). Delong test, NRI, and IDI showed that the CR model had significant differences from other models (P < 0.05). Calibration curves demonstrated good agreement, and DCA revealed significant benefits of the CR model.

CONCLUSION

The CR model based on preoperative MRI radiomics features and clinical risk factors can preoperatively predict the PNI status of RC noninvasively, which facilitates individualized treatment of RC patients.

The depth of perineural invasion is an independent prognostic factor for stage II colorectal cancer

BACKGROUND

Perineural invasion (PNI) is the invasion of nerves by cancer cells and is associated with poor survival in stage II colorectal cancer. However, PNI can be further subdivided according to the depth of invasion, and the depth of PNI has not been clearly linked to prognosis.

METHOD

This study aimed to assess the prognostic value of different depths of PNI in stage II colorectal cancer. We defined PNI in the submucosal plexus and myenteric plexus as superficial perineural invasion (sup-PNI) and PNI in the subserous plexus as deep perineural invasion (deep-PNI). Patients were divided into three groups based on the depth of PNI: sup-PNI, deep-PNI and non-PNI. Then, univariate and multivariate Cox regression analyses were conducted to evaluate the role of PNI in the prognosis of stage II colorectal cancer.

RESULTS

This study enrolled 3508 patients with stage II colorectal cancer who underwent resection for primary colorectal lesions between January 2013 and September 2019. Clinicopathological features, including elevated carcinoembryonic antigen (CEA) levels, T4 stage, poor differentiation, deficient DNA mismatch repair (dMMR), and vascular invasion, were correlated with deep-PNI. Multivariate analyses revealed that deep-PNI was associated with worse overall survival (OS; hazard ratio [HR], 3.546; 95% confidence interval [CI], 2.307-5.449; P < 0.001) and disease-free survival (DFS; HR, 2.921; 95% CI, 2.032-4.198; P < 0.001), compared with non-PNI. Conversely, no significant difference in OS or DFS was observed between the sup-PNI and non-PNI groups in multivariate analyses.

CONCLUSIONS

The study demonstrated that the depth of PNI was an independent prognostic factor for patients with stage II colorectal cancer, and patients with deep PNI had a worse prognosis. Thus, patients with PNI require further subdivision according to the depth of invasion.

The value of machine learning based on CT radiomics in the preoperative identification of peripheral nerve invasion in colorectal cancer: a two-center study

BACKGROUND

We aimed to explore the application value of various machine learning (ML) algorithms based on multicenter CT radiomics in identifying peripheral nerve invasion (PNI) of colorectal cancer (CRC).

METHODS

A total of 268 patients with colorectal cancer who underwent CT examination in two hospitals from January 2016 to December 2022 were considered. Imaging and clinicopathological data were collected through the Picture Archiving and Communication System (PACS). The Feature Explorer software (FAE) was used to identify the peripheral nerve invasion of colorectal patients in center 1, and the best feature selection and classification channels were selected. Finally, the best feature selection and classifier pipeline were verified in center 2.

RESULTS

The six-feature models using RFE feature selection and GP classifier had the highest AUC values, which were 0.610, 0.699, and 0.640, respectively. FAE generated a more concise model based on one feature (wavelet-HLL-glszm-LargeAreaHighGrayLevelEmphasis) and achieved AUC values of 0.614 and 0.663 on the validation and test sets, respectively, using the "one standard error" rule. Using ANOVA feature selection, the GP classifier had the best AUC value in a one-feature model, with AUC values of 0.611, 0.663, and 0.643 on the validation, internal test, and external test sets, respectively. Similarly, when using the "one standard error" rule, the model based on one feature (wave-let-HLL-glszm-LargeAreaHighGrayLevelEmphasis) achieved AUC values of 0.614 and 0.663 on the validation and test sets, respectively.

CONCLUSIONS

Combining artificial intelligence and radiomics features is a promising approach for identifying peripheral nerve invasion in colorectal cancer. This innovative technique holds significant potential for clinical medicine, offering broader application prospects in the field.

CRITICAL RELEVANCE STATEMENT

The multi-channel ML method based on CT radiomics has a simple operation process and can be used to assist in the clinical screening of patients with CRC accompanied by PNI.

KEY POINTS

• Multi-channel ML in the identification of peripheral nerve invasion in CRC. • Multi-channel ML method based on CT-radiomics can detect the PNI of CRC. • Early preoperative identification of PNI in CRC is helpful to improve the formulation of treatment strategies and the prognosis of patients.

A prediction nomogram for perineural invasion in colorectal cancer patients: a retrospective study

BACKGROUND

Perineural invasion (PNI), as the fifth recognized pathway for the spread and metastasis of colorectal cancer (CRC), has increasingly garnered widespread attention. The preoperative identification of whether colorectal cancer (CRC) patients exhibit PNI can assist clinical practitioners in enhancing preoperative decision-making, including determining the necessity of neoadjuvant therapy and the appropriateness of surgical resection. The primary objective of this study is to construct and validate a preoperative predictive model for assessing the risk of perineural invasion (PNI) in patients diagnosed with colorectal cancer (CRC).

MATERIALS AND METHODS

A total of 335 patients diagnosed with colorectal cancer (CRC) at a single medical center were subject to random allocation, with 221 individuals assigned to a training dataset and 114 to a validation dataset, maintaining a ratio of 2:1. Comprehensive preoperative clinical and pathological data were meticulously gathered for analysis. Initial exploration involved conducting univariate logistic regression analysis, with subsequent inclusion of variables demonstrating a significance level of p < 0.05 into the multivariate logistic regression analysis, aiming to ascertain independent predictive factors, all while maintaining a p-value threshold of less than 0.05. From the culmination of these factors, a nomogram was meticulously devised. Rigorous evaluation of this nomogram's precision and reliability encompassed Receiver Operating Characteristic (ROC) curve analysis, calibration curve assessment, and Decision Curve Analysis (DCA). The robustness and accuracy were further fortified through application of the bootstrap method, which entailed 1000 independent dataset samplings to perform discrimination and calibration procedures.

RESULTS

The results of multivariate logistic regression analysis unveiled independent risk factors for perineural invasion (PNI) in patients diagnosed with colorectal cancer (CRC). These factors included tumor histological differentiation (grade) (OR = 0.15, 95% CI = 0.03-0.74, p = 0.02), primary tumor location (OR = 2.49, 95% CI = 1.21-5.12, p = 0.013), gross tumor type (OR = 0.42, 95% CI = 0.22-0.81, p = 0.01), N staging in CT (OR = 3.44, 95% CI = 1.74-6.80, p < 0.001), carcinoembryonic antigen (CEA) level (OR = 3.13, 95% CI = 1.60-6.13, p = 0.001), and platelet-to-lymphocyte ratio (PLR) (OR = 2.07, 95% CI = 1.08-3.96, p = 0.028).These findings formed the basis for constructing a predictive nomogram, which exhibited an impressive area under the receiver operating characteristic (ROC) curve (AUC) of 0.772 (95% CI, 0.712-0.833). The Hosmer-Lemeshow test confirmed the model's excellent fit (p = 0.47), and the calibration curve demonstrated consistent performance. Furthermore, decision curve analysis (DCA) underscored a substantial net benefit across the risk range of 13% to 85%, reaffirming the nomogram's reliability through rigorous internal validation.

CONCLUSION

We have formulated a highly reliable nomogram that provides valuable assistance to clinical practitioners in preoperatively assessing the likelihood of perineural invasion (PNI) among colorectal cancer (CRC) patients. This tool holds significant potential in offering guidance for treatment strategy formulation.

Evaluating the Role of Methylated Circulating Tumor DNA in Combination With Pathological Prognostic Factors for Predicting Recurrence of Colorectal Cancer

Background

Colorectal cancer (CRC) has a high rate of recurrence, in particular for advanced disease, but prognosis based on staging and pathology at surgery can have limited efficacy. The presence of circulating tumor DNA (ctDNA) at diagnosis could be used to improve the prediction for disease recurrence.

Objectives

To assess the impact of detecting methylated BCAT1/IKZF1 ctDNA at diagnosis in combination with demographic, lifestyle, clinical factors and tumor pathology, to assess predictive value for recurrence.

Design

A retrospective cohort study.

Methods

The cohort included 180 patients (36 with recurrent CRC), who had undergone complete treatment and surveillance for a minimum of 3 years. Participant clinical details and ctDNA methylated BCAT1/IKZF1 results were compared between those with and without recurrence, and cox regression analysis assessed each factor on disease-free survival.

Results

Clinical factors independently associated with reduced disease-free survival included nodal involvement (HR = 3.83, 95% CI 1.56-9.43, P = .003), M1 stage (HR = 4.41, 95% CI 1.18-16.45, P = .027), a resection margin less than 2 mm (HR = 4.60, 95% CI 1.19-17.76, P = .027), perineural involvement (HR = 2.50, 95% CI 1.01-6.17, P = .047) and distal tumors (HR = 3.13, 95% CI 1.07-9.18, P = .037). Methylated BCAT1/IKZF1 was detected in 51.7% (93/180) of pre-treatment plasma samples. When a positive ctDNA finding was considered in combination with these clinical prognostic factors, there was improved predictive power of recurrence for patients with perineural involvement (HR = 4.44, 95% CI 1.92-10.26, P < .001), and it marginally improved the predictive factor for M1 stage (HR = 7.59, 95% CI 2.30-25.07, P = .001) and distal tumors (HR = 5.04, 95% CI 1.88-13.49, P = .001).

Conclusions

Nodal invasion, metastatic disease, distal tumor site, low resection margins and perineural invasion were associated with disease recurrence. Pre-treatment methylated ctDNA measurement can improve the predictive value for recurrence in a subset of patients, particularly those with perineural involvement.

Registration

Australian and New Zealand Clinical Trials Registry #12611000318987.

Investigation of the potential of miRNA candidates as non-invasive biomarkers for the diagnosis and follow-up of colorectal cancer

BACKGROUND

Colorectal cancer (CRC) is the third most common cancer worldwide, and despite advances in treatment, molecular biomarkers are needed for both early diagnosis and prognosis monitoring. It is known that microRNAs (miRNA), one of the epigenetic mechanisms, are effective in the initiation and development of cancer by regulating the activity of tumor suppressors and/or oncogenes. In this study, the potential of the molecules let-7, miRNA125b, and miRNA30a, which are known to play a role in cellular processes, as biomarkers for colorectal cancer and their molecular mechanisms were investigated in this model. The aim was to evaluate the diagnostic, prognostic, and predictive utility of the target miRNAs in colorectal cancer patients.

MATERIAL AND METHODS

The expression changes of miRNAs let-7, miRNA125b, and miRNA30a were investigated by miRNAs isolation and cDNA synthesis from the serum samples of 60 patients diagnosed with CRC or from the serum samples of 20 healthy individuals. The calculation was performed using the quantitative real-time polymerase chain reaction method to determine the expression level. The results were compared with clinical parameters.

RESULT

An 8-fold decrease in the expression of let-7 and miRNA125b and a 60-fold decrease in the expression of miRNA30a were found in the serum samples of patients diagnosed with colorectal cancer (CRC) compared to the healthy group. A decrease in let-7 was observed in 53.3%, miRNA125b in 58.3%, and miRNA30a in 55% of patients. A significant correlation was found between the reduced expression status and the stage, lymph nodes, local recurrence, and metastasis (p < 0.05). The ROC analysis showed that the miRNA30a level could be a diagnostic biomarker for CRC (p < 0.001). No significant impact of target miRNA expression changes on overall disease survival was observed.

CONCLUSION

It is thought that the target miRNA30a can be used for early diagnosis and screening and that the target miRNA let-7, miRNA125b, and miRNA30a can be used as non-invasive biomarkers for disease follow-up, with larger patient studies being conducted on CRC patients.

Perineural invasion in colorectal cancer: mechanisms of action and clinical relevance

BACKGROUND

In recent years, the significance of the nervous system in the tumor microenvironment has gained increasing attention. The bidirectional communication between nerves and cancer cells plays a critical role in tumor initiation and progression. Perineural invasion (PNI) occurs when tumor cells invade the nerve sheath and/or encircle more than 33% of the nerve circumference. PNI is a common feature in various malignancies and is associated with tumor invasion, metastasis, cancer-related pain, and unfavorable clinical outcomes. The colon and rectum are highly innervated organs, and accumulating studies support PNI as a histopathologic feature of colorectal cancer (CRC). Therefore, it is essential to investigate the role of nerves in CRC and comprehend the mechanisms of PNI to impede tumor progression and improve patient survival.

CONCLUSION

This review elucidates the clinical significance of PNI, summarizes the underlying cellular and molecular mechanisms, introduces various experimental models suitable for studying PNI, and discusses the therapeutic potential of targeting this phenomenon. By delving into the intricate interactions between nerves and tumor cells, we hope this review can provide valuable insights for the future development of CRC treatments.

Combining pathological risk factors and T, N staging to optimize the assessment for risk stratification and prognostication in low-risk stage III colon cancer

BACKGROUND

This study aimed to investigate the combined pathological risk factors (PRFs) to stratify low-risk (pT1-3N1) stage III colon cancer (CC), providing a basis for individualized treatment in the future.

PATIENTS AND METHODS

PRFs for low-risk stage III CC were identified using COX model. Low-risk stage III CC was risk-grouped combining with PRFs, and survival analysis were performed using Kaplan-Meier. The Surveillance, Epidemiology, and End Results (SEER) databases was used for external validation.

RESULTS

Nine hundred sixty-two stage III CC patients were included with 634 (65.9%) as low risk and 328 (34.1%) as high risk. Poor differentiation (OS: P = 0.048; DFS: P = 0.011), perineural invasion (OS: P = 0.003; DFS: P < 0.001) and tumor deposits (OS: P = 0.012; DFS: P = 0.003) were identified as PRFs. The prognosis of low-risk CC combined with 2 PRFs (OS: HR = 3.871, 95%CI, 2.004-7.479, P < 0.001; DFS: HR = 3.479, 95%CI, 2.158-5.610, P < 0.001) or 3 PRFs (OS: HR = 5.915, 95%CI, 1.953-17.420, P = 0.002; DFS: HR = 5.915, 95%CI, 2.623-13.335, P < 0.001) was similar to that of high-risk CC (OS: HR = 3.927, 95%CI, 2.317-6.656, P < 0.001; DFS: HR = 4.132, 95%CI, 2.858-5.974, P < 0.001). In the SEER database, 18,547 CC patients were enrolled with 10,023 (54.0%) as low risk and 8524 (46.0%) as high risk. Low-risk CC combined with 2 PRFs (OS: HR = 1.857, 95%CI, 1.613-2.139, P < 0.001) was similar to that of high-risk CC without PRFs (HR = 1.876, 95%CI, 1.731-2.033, P < 0.001).

CONCLUSION

Combined PRFs improved the risk stratification of low-risk stage III CC, which could reduce the incidence of undertreatment and guide adjuvant chemotherapy.

Prognostic value of normal levels of preoperative tumor markers in colorectal cancer

Carcinoembryonic antigen (CEA), carbohydrate antigen 19-9 (CA19-9), carbohydrate antigen 125 (CA125), and alpha-fetoprotein (AFP) are widely used tumor markers for colorectal cancer (CRC), but their clinical significance is unknown when the levels of these tumor markers were within the normal range. This retrospective study included 2145 CRC patients. The entire cohort was randomly divided into training and validation datasets. The optimal cut-off values of tumor markers were calculated using X-tile software, and univariate and multivariate analyses were performed to assess its association with overall survival (OS). The nomogram model was constructed and validated. The entire cohort was randomly divided into a training dataset (1502 cases, 70%) and a validation dataset (643 cases,30%). Calculated from the training dataset, the optimal cut-off value was 2.9 ng/mL for CEA, 10.1 ng/mL for CA19-9, 13.4 U/mL for CA125, and 1.8 ng/mL for AFP, respectively. Multivariate analysis revealed that age, tumor location, T stage, N stage, preoperative CA19-9, and CA125 levels were independent prognostic predictors. Even within the normal range, CRC patients with relatively high levels of CA19-9 or CA125 worse OS compared to those with relatively low levels. Then, based on the independent prognostic predictors from multivariate analysis, two models with/without (model I/II) CA19-9 and CA125 were built, model I showed better prediction and reliability than model II. Within the normal range, relatively high levels of preoperative CA19-9 and CA125 were significantly associated with poor OS in CRC patients. The nomogram based on CA19-9 and CA125 levels showed improved predictive accuracy ability for CRC.

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.

Development and validation of a combined nomogram for predicting perineural invasion status in rectal cancer via computed tomography-based radiomics

AIM

This study aimed to create and validate a clinic-radiomics nomogram based on computed tomography (CT) imaging for predicting preoperative perineural invasion (PNI) of rectal cancer (RC).

MATERIAL AND METHODS

This study enrolled 303 patients with RC who were divided into training (n = 242) and test datasets (n = 61) in an 8:2 ratio with all their clinical outcomes. A total of 3,296 radiomic features were extracted from CT images. Five machine learning (ML) models (logistic regression (LR)/K-nearest neighbor (KNN)/multilayer perceptron (MLP)/support vector machine (SVM)/light gradient boosting machine (LightGBM)) were developed using radiomic features derived from the arterial and venous phase images, and the model with the best diagnostic performance was selected. By combining the radiomics and clinical signatures, a fused nomogram model was constructed.

RESULTS

After using the Mann-Whitney U-test and least absolute shrinkage and selection operator (LASSO) to remove redundant features, the MLP model proved to be the most efficient among the five ML models. The fusion nomogram based on MLP prediction probability further improves the ability to predict the PNI status. The area under the curve (AUC) of the training and test sets was 0.883 and 0.889, respectively, which were higher than those of the clinical (training set, AUC = 0.710; test set, AUC = 0.762) and radiomic models (training set, AUC = 0.840; test set, AUC = 0.834).

CONCLUSIONS

The clinical-radiomics combined nomogram model based on enhanced CT images efficiently predicted the PNI status of patients with RC.

The effect of adjuvant chemotherapy on survival in node negative colorectal cancer with or without perineural invasion: a systematic review and meta-analysis

Purpose

It was aimed at assessing the benefits of adjuvant chemotherapy (ACT) for patients with node-negative colorectal cancer (CRC) either with or without perineural invasion (PNI).

Methods

We systematically searched PubMed, Cochrane Library, Embase, and Web of Science from database inception through October 1, 2023. Survival outcomes were analyzed using hazard ratios (HRs) and corresponding 95% confidence intervals (CIs). The methodological quality of included studies was assessed using the Newcastle-Ottawa Scale (NOS). Heterogeneity for the descriptive meta-analyses was quantified using the I2 statistic.

Results

Ten studies included in this review. ACT improved overall survival (OS) (HR 0.52, 95% CI 0.40-0.69) and disease-free survival (DFS) (HR 0.53, 95% CI 0.35-0.82) in PNI + patients but did not affect DFS (HR 1.13, 95% CI 0.72-1.77) in PNI- patients. A disease-specific survival (DSS) benefit with chemotherapy was observed in PNI + (HR 0.76, 95% CI 0.58-0.99) and PNI- patients (HR 0.76, 95% CI 0.57-1.00). And PNI decreased DFS (HR 1.94, 95% CI 1.52-2.47) and OS (HR 1.75, 95% CI 0.96-3.17) in node-negative CRC.

Conclusions

In conclusion, chemotherapy appears most beneficial for survival outcomes in node-negative patients with PNI, but may also confer some advantage in those without PNI.

Systematic Review Registration

Identifier INPLASY2021120103.

Enteric neuro-immune interactions in intestinal health and disease

The enteric nervous system is an autonomous neuronal circuit that regulates many processes far beyond the peristalsis in the gastro-intestinal tract. This circuit, consisting of enteric neurons and enteric glial cells, can engage in many intercellular interactions shaping the homeostatic microenvironment in the gut. Perhaps the most well documented interactions taking place, are the intestinal neuro-immune interactions which are essential for the fine-tuning of oral tolerance. In the context of intestinal disease, compelling evidence demonstrates both protective and detrimental roles for this bidirectional neuro-immune signaling. This review discusses the different immune cell types that are recognized to engage in neuronal crosstalk during intestinal health and disease. Highlighting the molecular pathways involved in the neuro-immune interactions might inspire novel strategies to target intestinal disease.

Colorectal Carcinomas: Searching for New Histological Parameters Associated with Lymph Node Metastases

Background and Objectives: Colorectal cancer (CRC) continues to be an essential public health problem. Our study aimed to evaluate the prognostic significance of classic prognostic factors and some less-studied histopathological parameters in CRC. Materials and Methods: We performed a retrospective study on 71 colorectal carcinoma patients who underwent surgery at the "Pius Brînzeu" County Clinical Emergency Hospital in Timișoara, Romania. We analyzed the classic parameters but also tumor budding (TB), poorly differentiated clusters (PDCs) of cells, tumor-infiltrating lymphocytes (TILs), and the configuration of the tumor border on hematoxylin-eosin slides. Results: A high degree of malignancy (p = 0.006), deep invasion of the intestinal wall (p = 0.003), an advanced stage of the disease (p < 0.0001), lymphovascular invasion (p < 0.0001), perineural invasion (p < 0.0001), high-grade TB (p < 0.0001), high-grade PDCs (p < 0.0001), infiltrative tumor border configuration (p < 0.0001) showed a positive correlation with lymph node metastases. Conclusions: The analyzed parameters positively correlate with unfavorable prognostic factors in CRC. We highlight the value of classic prognostic factors along with a series of less-known parameters that are more accessible and easier to evaluate using standard staining techniques and that could predict the risk of relapse or aggressive evolution in patients with CRC.

The Incidence and Prognosis Value of Perineural Invasion in Rectal Carcinoma: From Meta-Analyses and Real-World Clinical Pathological Features

AIMS

Perineural invasion (PNI) is a special type of metastasis of several cancers and has been reported as being a factor for poor prognosis in colorectal carcinoma. However, investigations of PNI in only rectal cancer and a comprehensive analysis combining meta-analyses with real-world case studies remain lacking.

MATERIALS AND METHODS

First, articles from 2000 to 2020 concerning the relationship between PNI and rectal cancer prognoses and clinical features were meta-analysed. Subsequently, we carried out a retrospective analysis of 312 rectal cancer cases that underwent radical surgery in the real world. The incidence of PNI and the relationship between PNI and prognosis, as well as clinicopathological factors, were investigated.

RESULTS

The incidence of PNI was 23.09% and 33.01% in the meta-analysis and clinical cases, respectively. PNI occurred as early as stage I (2.94%). Moreover, neoadjuvant therapy significantly reduced the PNI-positive rate (20.34% versus 26.54%). Both meta-analysis and real-world clinical case studies suggested that PNI-positive patients had poorer prognoses than PNI-negative patients. We established an effective risk model consisting of T stage, differentiation and lymphovascular invasion to predict PNI in rectal cancer.

CONCLUSION

PNI is a poor prognostic factor for rectal cancer and could occur even in stage I. Additionally, neoadjuvant therapy could sufficiently reduce the PNI-positive rate. T stage, lymphovascular invasion and differentiation grade were independent risk factors for PNI and the risk model that included these factors could predict the probability of PNI.

Unraveling the Mysteries of Perineural Invasion in Benign and Malignant Conditions

Perineural invasion (PNI) is defined as the dissemination of neoplastic cells within the perineural space. PNI can be a strong indicator of malignancy and is linked to poor prognosis and adverse outcomes in various malignant neoplasms; nevertheless, it can also be seen in benign pathologic conditions. In this review article, we discuss various signaling pathways and neurotrophic factors implicated in the development and progression of PNI. We also describe the methodology, benefits, and limitations of different in vitro, ex vivo, and in vivo models of PNI. The spectrum of presentation for PNI can range from diffuse spread within large nerves ("named" nerves) all the way through localized spread into unnamed microscopic nerves. Therefore, the clinical significance of PNI is related to its extent rather than its mere presence or absence. In this article, we discuss the guidelines for the identification and quantification of PNI in different malignant neoplasms based on the College of American Pathologists (CAP) and World Health Organization (WHO) recommendations. We also describe benign pathologic conditions and neoplasms demonstrating PNI and potential mimics of PNI. Finally, we explore avenues for the future development of targeted therapy options via modulation of signaling pathways involved in PNI.

Mini-Review: Enteric glia of the tumor microenvironment: An affair of corruption

The tumor microenvironment corresponds to a complex mixture of bioactive products released by local and recruited cells whose normal functions have been "corrupted" by cues originating from the tumor, mostly to favor cancer growth, dissemination and resistance to therapies. While the immune and the mesenchymal cellular components of the tumor microenvironment in colon cancer have been under intense scrutiny over the last two decades, the influence of the resident neural cells of the gut on colon carcinogenesis has only very recently begun to draw attention. The vast majority of the resident neural cells of the gastrointestinal tract belong to the enteric nervous system and correspond to enteric neurons and enteric glial cells, both of which have been understudied in the context of colon cancer development and progression. In this review, we especially discuss available evidence on enteric glia impact on colon carcinogenesis. To highlight "corrupted" functioning in enteric glial cells of the tumor microenvironment and its repercussion on tumorigenesis, we first review the main regulatory effects of enteric glial cells on the intestinal epithelium in homeostatic conditions and we next present current knowledge on enteric glia influence on colon tumorigenesis. We particularly examine how enteric glial cell heterogeneity and plasticity require further appreciation to better understand the distinct regulatory interactions enteric glial cell subtypes engage with the various cell types of the tumor, and to identify novel biological targets to block enteric glia pro-carcinogenic signaling.

Interaction analysis of high-risk pathological features on adjuvant chemotherapy survival benefit in stage II colon cancer patients: a multi-center, retrospective study

BACKGROUND

We aimed to analyze the benefit of adjuvant chemotherapy in high-risk stage II colon cancer patients and the impact of high-risk factors on the prognostic effect of adjuvant chemotherapy.

METHODS

This study is a multi-center, retrospective study, A total of 931 patients with stage II colon cancer who underwent curative surgery in 8 tertiary hospitals in China between 2016 and 2017 were enrolled in the study. Cox proportional hazard model was used to assess the risk factors of disease-free survival (DFS) and overall survival (OS) and to test the multiplicative interaction of pathological factors and adjuvant chemotherapy (ACT). The additive interaction was presented using the relative excess risk due to interaction (RERI). The Subpopulation Treatment Effect Pattern Plot (STEPP) was utilized to assess the interaction of continuous variables on the ACT effect.

RESULTS

A total of 931 stage II colon cancer patients were enrolled in this study, the median age was 63 years old (interquartile range: 54-72 years) and 565 (60.7%) patients were male. Younger patients (median age, 58 years vs 65 years; P < 0.001) and patients with the following high-risk features, such as T4 tumors (30.8% vs 7.8%; P < 0.001), grade 3 lesions (36.0% vs 22.7%; P < 0.001), lymphovascular invasion (22.1% vs 6.8%; P < 0.001) and perineural invasion (19.4% vs 13.6%; P = 0.031) were more likely to receive ACT. Patients with perineural invasion showed a worse OS and marginally worse DFS (hazardous ratio [HR] 2.166, 95% confidence interval [CI] 1.282-3.660, P = 0.004; HR 1.583, 95% CI 0.985-2.545, P = 0.058, respectively). Computing the interaction on a multiplicative and additive scale revealed that there was a significant interaction between PNI and ACT in terms of DFS (HR for multiplicative interaction 0.196, p = 0.038; RERI, -1.996; 95%CI, -3.600 to -0.392) and OS (HR for multiplicative interaction 0.112, p = 0.042; RERI, -2.842; 95%CI, -4.959 to -0.725).

CONCLUSIONS

Perineural invasion had prognostic value, and it could also influence the effect of ACT after curative surgery. However, other high-risk features showed no implication of efficacy for ACT in our study.

TRIAL REGISTRATION

This study is registered on ClinicalTrials.gov, NCT03794193 (04/01/2019).

Negative Prognostic Impact of Tumor Deposits in Rectal Cancer: A National Study Cohort

OBJECTIVE

To investigate whether tumor deposits (TDs) in rectal cancer are associated with increased recurrence risk and decreased survival.

BACKGROUND

Tumor deposits (TDs) are considered a risk factor for recurrence after colon cancer resection, and the presence of TDs prompts adjuvant chemotherapy. The prognostic relevance of TDs in rectal cancer requires further exploration.

METHODS

All patients treated with abdominal resection surgery for rectal cancer in Sweden between 2011 and 2014 were eligible for inclusion in this retrospective cohort study based on prospectively collected data from the Swedish Colorectal Cancer Registry. The primary endpoint was local recurrence or distant metastasis. Secondary outcomes were overall and relative survival.

RESULTS

Five thousand four hundred fifty-five patients were identified of which 3769 patients were analyzed after exclusion. TDs were found in 404 (10.7%) patients, including 140 (3.7%) patients with N1c-status. In TD-positive patients, local recurrence and distant metastasis rates at 5 years were 6.3% [95% CI 3.8-8.8%] and 38.9% [95% CI, 33.6-43.5%] compared with 2.7% [95% CI, 2.1-3.3%] and 14.3% [95% CI, 13.1-15.5%] in TD-negative patients. In multivariable regression analysis, the risk of local recurrence and distant metastasis were increased; HR 1.86 [95% CI, 1.09-3.19; P =0.024] and 1.87 [95% CI, 1.52-2.31; P =<0.001], respectively. Overall survival at 5 years was 68.8% [95% CI, 64.4-73.4%] in TD-positive patients and 80.7% [95% CI, 79.4-82.1%] in TD-negative patients. pN1c-patients had similar outcomes regarding local recurrence, distant metastasis, and survival as pN1a-b stage patients. TD-positive pN1a-b patients had significantly worse outcomes whereas TDs did not affect outcomes in pN2a-b patients.

CONCLUSION

This study suggests that TDs have a negative impact on the prognosis in rectal cancer. Thus, efforts should be made to diagnose TD-positive rectal cancer patients preoperatively.

Dichotomous colorectal cancer behaviour

Colorectal cancer (CRC) is the third most common malignant tumor and one of the deadliest cancers. At molecular level, CRC is a heterogeneous disease that could be divided in four Consensus Molecular Subtypes. Given the differences in the disease due to its anatomical location (proximal and distal colon), another classification should be considered. Here, we review the current knowledge on CRC dichotomic´s behaviour based on two different entities; right and left-sided tumors, their impact on clinical trial data, microbiota spatial composition and the interaction with the nervous system. We discuss recent advances in understanding how the spatial tumor heterogeneity influences the tumor growth, progression, and responses to current therapies.

Multiple High-Risk Features for Stage II Colon Carcinoma Portends Worse Survival Than Stage III Disease

BACKGROUND

High-risk features in stage II colon cancer worsen survival and serve as an impetus for adjuvant chemotherapy. Limited data exist on the effect of multiple high-risk features on survival.

OBJECTIVE

The study aimed to compare the survival of 0, 1, or multiple high-risk features in stage II to stage III colon cancer.

DESIGN

Patients with stage II and III colon cancer diagnosed between 2010 and 2016 were identified using the Survival, Epidemiology, and End Results database. Patients with stage II colon cancer were then classified according to the presence of 0, 1, or 2 or more of the following high-risk features: pathologic T4, perineural invasion, fewer than 12 lymph nodes assessed, or poor histologic differentiation. Overall survival and cause-specific survival were calculated. Each group was then stratified on the basis of whether chemotherapy was given.

SETTINGS

This study used the Survival, Epidemiology, and End Results database (2010-2016).

PATIENTS

Patients who had stage II or III colon cancer were included.

MAIN OUTCOME MEASURES

The primary outcome measures were 5-year overall survival and cause-specific survival.

RESULTS

A total of 65,831 patients were studied. Of these, 18,056 patients with stage II cancer had 0 high-risk features, 9426 had 1 high-risk feature, and 3503 had 2 or more high-risk features. There were 34,842 patients diagnosed with stage III disease. The 5-year overall survival and cause-specific survival for patients with stage II cancer with 2 or more high-risk features (49.2%, 59.5%) were lower than those without high-risk features (74.9%, 90.7%), with 1 high-risk feature (67.1%, 82.4%), or stage III disease (59.1%, 68.1%; p < 0.05). Although chemotherapy is associated with improved cause-specific survival in stage III disease, it is associated with worse cause-specific survival in patients with stage II disease.

LIMITATIONS

This study being a retrospective database analysis is the main limitation. Also, lymphovascular invasion, margin status, and clinical obstruction or perforation were absent from the dataset.

CONCLUSIONS

Multiple high-risk features in stage II colon cancer predict worse survival than lymph node metastasis. Chemotherapy is associated with adverse cause-specific survival in patients with stage II disease. Further study into this group should focus on the type and duration of adjuvant therapy and biological features of these tumors. See Video Abstract at http://links.lww.com/DCR/B929 .

MLTIPLES CARACTERSTICAS DE ALTO RIESGO PARA EL CARCINOMA DE COLON EN ESTADIO II PRESAGIAN PEOR SUPERVIVENCIA QUE LA ENFERMEDAD EN ESTADIO III

ANTECEDENTES:Las características de alto riesgo en el cáncer de colon en estadio II empeoran la supervivencia y sirven como impulso para la quimioterapia adyuvante. Existen datos limitados sobre el efecto de múltiples características de alto riesgo en la supervivencia.OBJETIVO:Comparar la supervivencia de cero, una o múltiples características de alto riesgo en el cáncer de colon en estadio II con la enfermedad en estadio III.DISEÑO:Los pacientes con cáncer de colon en estadio II y III diagnosticados entre 2010 y 2016 se identificaron mediante la base de datos de supervivencia, epidemiología y resultados finales. Luego, los pacientes en etapa II se clasificaron según la presencia de cero, 1 o 2+ de las siguientes características de alto riesgo: T4 patológico, invasión perineural, menos de 12 ganglios linfáticos evaluados (< 12 ganglios linfáticos) o mala diferenciación histológica. Se calculó la supervivencia observada y específica de la causa. Luego, cada grupo se estratificó en función de si se administró quimioterapia.ESCENARIO:Este estudio utilizó la base de datos de supervivencia, epidemiología y resultados finales, 2010-2016.PACIENTES:Los pacientes tenían cáncer de colon en estadio II o III.PRINCIPALES MEDIDAS DE RESULTADO:La medida principal fue la supervivencia observada a 5 años y la supervivencia por causa específica.RESULTADOS:Se estudiaron un total de 65,831 pacientes. 18,056 pacientes estaban en estadio II sin características de alto riesgo, 9.426 con 1 característica de alto riesgo y 3.503 con 2+ características de alto riesgo. Hubo 34.842 pacientes a los que se les diagnosticó enfermedad en estadio III. La supervivencia observada a los 5 años y la supervivencia específica de la causa para los pacientes con cáncer en estadio II con 2+ características de alto riesgo (49.2 %, 59.5 %) fueron más bajas, en comparación con aquellos sin características de alto riesgo (74.9 %, 90.7 %), con 1 característica de alto riesgo (67.1 %, 82.4 %) o enfermedad en estadio III (59.1 %, 68.1 %) (p < 0.05). Si bien la quimioterapia se asocia con una mejor supervivencia por causa específica en la enfermedad en estadio III, se asocia con una peor supervivencia por causa específica en pacientes con enfermedad en estadio II.LIMITACIONES:Este es un análisis de base de datos retrospectivo. La invasión linfovascular, el estado de los márgenes y la obstrucción o perforación clínicas estaban ausentes en la base de datos.CONCLUSIONES:Múltiples características de alto riesgo en el cáncer de colon en estadio II predicen una peor supervivencia que la metástasis en los ganglios linfáticos. La quimioterapia se asocia con una supervivencia específica de causa adversa en pacientes con enfermedad en estadio II. El estudio adicional de este grupo deberá centrarse en el tipo y la duración de la terapia adyuvante y las características biológicas de estos tumores. Consulte Video Resumen en http://links.lww.com/DCR/B929 . (Traducción-Dr. Jorge Silva Velazco ).

Prognostic Impact of Lymphatic Invasion, Venous Invasion, Perineural Invasion, and Tumor Budding in Rectal Cancer Treated With Neoadjuvant Chemoradiotherapy Followed by Total Mesorectal Excision

BACKGROUND

The diagnostic implications of lymphatic invasion, venous invasion, perineural invasion, and tumor budding in rectal cancer treated with neoadjuvant chemoradiotherapy are unknown.

OBJECTIVE

This study aimed to identify the prognostic impact of lymphatic invasion, venous invasion, perineural invasion, and tumor budding in locally advanced rectal cancer treated with neoadjuvant chemoradiotherapy.

DESIGN

This was a retrospective cohort study.

SETTINGS

This study was conducted at the Samsung Medical Center. Grouping was performed on the basis of lymphatic invasion, venous invasion, perineural invasion, and tumor budding status: no-risk group with 0 factor (n = 299), low-risk group with any 1 factor (n = 131), intermediate-risk group with any 2 factors (n = 75), and high-risk group with 3 or 4 risk factors (n = 32).

PATIENTS

Patients who underwent neoadjuvant chemoradiotherapy, followed by radical operation for locally advanced rectal cancer, from January 2010 to December 2015 were included.

MAIN OUTCOME MEASURES

The main outcome measures were disease-free and overall survival.

RESULTS

Disease-free and overall survival varied significantly between the groups in stage III ( p < 0.001 and p < 0.001). Disease-free survival in stage I differed between the no-risk group and the intermediate-risk group ( p = 0.026). In stage II, disease-free and overall survival differed between the no-risk group and the intermediate-risk group ( p = 0.010 and p = 0.045). In multivariable analysis, risk grouping was an independent prognostic factor for both disease-free (p <0.001) and overall survival ( p < 0.001).

LIMITATIONS

The inherent limitations are associated with the retrospective single-center study design.

CONCLUSIONS

Lymphatic invasion, venous invasion, perineural invasion, and tumor budding are strong prognostic factors for disease-free and overall survival in locally advanced rectal cancer treated with neoadjuvant chemoradiotherapy. Therefore, adjuvant chemotherapy is strongly recommended in patients with positive lymphatic invasion, venous invasion, perineural invasion, and tumor budding. See Video Abstract at http://links.lww.com/DCR/B919 .

IMPACTO PRONSTICO DE LA INVASIN LINFTICA, LA INVASIN VENOSA, LA INVASIN PERINEURAL Y LA GEMACIN TUMORAL EN EL CNCER DE RECTO TRATADO CON QUIMIORRADIOTERAPIA NEOADYUVANTE SEGUIDA DE ESCISIN TOTAL DEL MESORRECTO

ANTECEDENTES:Se desconocen las implicaciones diagnósticas de la invasión linfática, la invasión venosa, la invasión perineural y el crecimiento tumoral en el cáncer de recto tratado con quimiorradioterapia neoadyuvante.OBJETIVO:Este estudio fue diseñado para identificar el impacto pronóstico de la invasión linfática, la invasión venosa, la invasión perineural y la gemación tumoral en el cáncer de recto localmente avanzado tratado con quimiorradioterapia neoadyuvante.DISEÑO:Este estudio fue un estudio de cohorte retrospectivo.AJUSTES:Este estudio se realizó en el Centro Médico Samsung. La agrupación se realizó en función de la invasión linfática, la invasión venosa, la invasión perineural y el estado de crecimiento del tumor: grupo sin riesgo con 0 factores (n = 299), grupo de bajo riesgo con cualquier factor 1 (n = 131), grupo de riesgo intermedio con 2 factores cualquiera (n = 75), y un grupo de alto riesgo con 3 o 4 factores de riesgo (n = 32).PACIENTES:Se incluyeron un total de 537 pacientes que se sometieron a quimiorradioterapia neoadyuvante seguida de operación radical por cáncer de recto localmente avanzado desde enero de 2010 hasta diciembre de 2015.PRINCIPALES MEDIDAS DE RESULTADO:Las principales medidas de resultado fueron la supervivencia libre de enfermedad y la supervivencia general.RESULTADOS:La mediana del período de seguimiento fue de 77 meses, y la supervivencia libre de enfermedad a los 5 años y la supervivencia general a los 5 años variaron significativamente entre los grupos en el estadio III (p < 0,001, p < 0,001). La supervivencia libre de enfermedad a los 5 años en el estadio I difirió entre el grupo sin riesgo y el grupo de riesgo intermedio (p = 0,026). En el estadio II, la supervivencia libre de enfermedad a 5 años y la supervivencia global a 5 años difirieron entre el grupo sin riesgo y el grupo de riesgo intermedio p = 0,010, p = 0,045). En el análisis multivariable, la agrupación de riesgo fue un factor pronóstico independiente tanto para la supervivencia libre de enfermedad (p < 0,001) como para la supervivencia global (p < 0,001).LIMITACIÓN:Las limitaciones inherentes están asociadas con el diseño de estudio retrospectivo de un solo centro..CONCLUSIÓN:La invasión linfática, la invasión venosa, la invasión perineural y la gemación tumoral son fuertes factores pronósticos para la supervivencia libre de enfermedad y la supervivencia general en el cáncer de recto localmente avanzado tratado con quimiorradioterapia neoadyuvante. Por lo tanto, se recomienda fuertemente la quimioterapia adyuvante en pacientes con invasión linfática positiva, invasión venosa, invasión perineural y tumor en en formacion. Consulte Video Resumen en http://links.lww.com/DCR/B919 . (Traducción-Dr Yolanda Colorado ).

Clinicopathological Analysis of Complicated Colorectal Cancer: A Five-Year Retrospective Study from a Single Surgery Unit

Patients with primary colorectal cancer can present with obstructions, tumor bleeding, or perforations, which represent acute complications. This paper aimed to analyze and compare the clinical and pathological profiles of two patient groups: one with colorectal cancer and a related complication and another without any specific complication. We performed a five-year retrospective study on colorectal cancer patients admitted to a surgery unit and comparatively explored the main clinical and pathological features of the tumors belonging to the two groups. A total of 250 patients with colorectal cancer were included in the analysis. Of these, 117 (46.8%) had presented a type of complication. The comparative analysis that examined several clinical and pathological parameters showed a statistically significant difference for unfavorable prognosis factors in the group with complications. This was evident for features such as vascular and perineural invasion, lymph node involvement, pathological primary tumor stage, and TNM stage. Colorectal cancers with a related complication belonged to a group of tumors with a more aggressive histopathologic profile and more advanced stages. Furthermore, the comparable incidence of cases in the two groups of patients warrants further efforts to be made in terms of early detection and prognosis prediction of colorectal cancer.

Deep learning for multi-class semantic segmentation enables colorectal cancer detection and classification in digital pathology images

In colorectal cancer (CRC), artificial intelligence (AI) can alleviate the laborious task of characterization and reporting on resected biopsies, including polyps, the numbers of which are increasing as a result of CRC population screening programs ongoing in many countries all around the globe. Here, we present an approach to address two major challenges in the automated assessment of CRC histopathology whole-slide images. We present an AI-based method to segment multiple ([Formula: see text]) tissue compartments in the H &E-stained whole-slide image, which provides a different, more perceptible picture of tissue morphology and composition. We test and compare a panel of state-of-the-art loss functions available for segmentation models, and provide indications about their use in histopathology image segmentation, based on the analysis of (a) a multi-centric cohort of CRC cases from five medical centers in the Netherlands and Germany, and (b) two publicly available datasets on segmentation in CRC. We used the best performing AI model as the basis for a computer-aided diagnosis system that classifies colon biopsies into four main categories that are relevant pathologically. We report the performance of this system on an independent cohort of more than 1000 patients. The results show that with a good segmentation network as a base, a tool can be developed which can support pathologists in the risk stratification of colorectal cancer patients, among other possible uses. We have made the segmentation model available for research use on https://grand-challenge.org/algorithms/colon-tissue-segmentation/ .

A nomogram for individually predicting the overall survival in colonic adenocarcinoma patients presenting with perineural invasion: a population study based on SEER database

Background

Colonic adenocarcinoma, representing the predominant histological subtype of neoplasms in the colon, is commonly denoted as colon cancer. This study endeavors to develop and validate a nomogram model designed for predicting overall survival (OS) in patients with colon cancer, specifically those presenting with perineural invasion (PNI).

Methods

The Surveillance, Epidemiology, and End Results (SEER) database supplied pertinent data spanning from 2010 to 2015, which facilitated the randomization of patients into distinct training and validation cohorts at a 7:3 ratio. Both univariate and multivariate analyses were employed to construct a prognostic nomogram based on the training cohort. Subsequently, the nomogram's accuracy and efficacy were rigorously evaluated through the application of a concordance index (C-index), calibration plots, decision curve analysis (DCA), and receiver operating characteristic (ROC) curves.

Results

In the training cohorts, multivariable analysis identified age, grade, T-stage, N-stage, M-stage, chemotherapy, tumor size, carcinoembryonic antigen (CEA), marital status, and insurance as independent risk factors for OS, all with P-values less than 0.05. Subsequently, a new nomogram was constructed. The C-index of this nomogram was 0.765 (95% CI: 0.755-0.775), outperforming the American Joint Committee on Cancer (AJCC) TNM staging system's C-index of 0.686 (95% CI: 0.674-0.698). Calibration plots for 3- and 5-year OS demonstrated good consistency, while DCA for 3- and 5-year OS revealed excellent clinical utility in the training cohorts. Comparable outcomes were observed in the validation cohorts. Furthermore, we developed a risk stratification system, which facilitated better differentiation among three risk groups (low, intermediate, and high) in terms of OS for all patients.

Conclusion

In this study, we have devised a robust nomogram and risk stratification system to accurately predict OS in colon cancer patients exhibiting PNI. This innovative tool offers valuable guidance for informed clinical decision-making, thereby enhancing patient care and management in oncology practice.

Stent as bridge to surgery decreases postoperative complications without worsening oncological outcomes: retrospective unicentric cohort study and stent placement protocol

BACKGROUND

Even if the use of stent as bridge to surgery (BTS) for obstructive colon cancer was described long ago, there is still much controversy on their use. Patient recovery before surgery and colonic desobstruction are just some of the reasons to defend this management that can be found in several available articles.

METHODS

This is a single-center, retrospective cohort study, including patients with obstructive colon cancer treated between 2010 and 2020. The primary aim of this study is to compare medium-term oncological outcomes (overall survival, disease-free survival) between stent as BTS and ES groups. The secondary aims are to compare perioperative results (in terms of approach, morbidity and mortality, and rate of anastomosis/stomas) between both groups and, within the BTS group, analyze whether there are any factors that may influence oncological outcomes.

RESULTS

A total of 251 patients were included. Patients belonging to the BTS cohort presented a higher rate of laparoscopic approach, required less intensive care management, less reintervention, and less permanent stoma rate, when comparing with patients who underwent urgent surgery (US). There were not significant differences in terms of disease-free survival and overall survival between the two groups. Lymphovascular invasion negatively affected oncological results but was not related with stent placement.

CONCLUSION

The stent as a bridge to surgery is a good alternative to urgent surgery, which leads to a decrease in postoperative morbidity and mortality without significantly worsening oncological outcomes.