Association between chemotherapy for surgically treated rectal cancer and second primary endometrial cancer.

To examine the potential correlation between chemotherapy and the risk of individual of second primary endometrial cancer (SEC) in patients with rectal cancer (RC) and assess survival outcomes. The study employed the Surveillance, Epidemiology, and End Results database (SEER) as the primary data source, it encompasses a substantial cohort of patients diagnosed with RC between 1975 and 2018. This study involved a total of 30,847 individuals diagnosed with RC, of whom 168 individuals (5.45‰) experienced SEC. Among them, 107 patients (3.47‰) received chemotherapy treatment, while 61 patients (1.98‰) did not receive chemotherapy. The analysis of the overall occurrence of SEC revealed a significant association between SEC and chemotherapy treatment. Univariate and multivariate analyses confirmed a significant association between chemotherapy treatment and an increased risk of developing SEC in RC patients. Upon implementation of a dynamic analysis on the variables of relative risk and standardized incidence ratios, the results revealed that the likelihood of SEC escalated in tandem with advancing age. The examination of patients who developed SEC after receiving and not receiving chemotherapy revealed no substantial disparities in the 10-year overall survival (OS) and (cancer-specific survival) CSS rates. The results were the same after propensity score matching. Nevertheless, a notable discrepancy emerged when comparing the OS and CSS rates at 10 years between patients afflicted with SEC subsequent to chemotherapy and those afflicted with primary endometrial cancer, and the result was the same situation in the no-chemotherapy group. The use of chemotherapy in RC patients has been associated with an increased probability of developing specific SEC. Therefore, it is imperative to prioritize efforts aimed at reducing chemotherapy-related SEC occurrences and improving the prognosis of affected individuals.

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

BACKGROUND: Neoadjuvant chemoradiotherapy (NCRT) followed by total mesorectal excision (TME) is the standard treatment for locally advanced rectal cancer (LARC). Mucinous adenocarcinoma (MAC) is a potential poor prognosis subgroup of rectal cancer. However, the predictive value of MAC in NCRT treatment of LARC is controversial. METHODS: A comprehensive literature search of PubMed, Embase, and the Cochrane Library was performed. All studies examining the effect of MAC on CRT response in LARC were included. Outcomes of MAC were compared with non-specific adenocarcinoma (AC) by using random-effects methods. Data were presented as odds ratios (ORs) with 95% confidence intervals (CIs). The main outcomes were the rates of pathological complete response (pCR), tumor and nodal down-staging, positive resection margin rate, local recurrence, and overall mortality. RESULTS: Fifteen studies containing comparative data on outcomes in a total of 9,238 patients receiving NCRT for LARC were eligible for inclusion. MAC had a reduced rate of pCR (OR, 0.38; 95% CI, 0.18-0.78) and tumor down-staging (OR, 0.31; 95% CI, 0.22-0.44) following NCRT compared with AC. MAC did not significantly affect nodal down-staging (OR, 0.42; 95% CI, 0.16-1.12) after NCRT. CONCLUSION: MAC of LARC was found to be a negative predictor of response to NCRT with lower rates of pCR and tumor down-staging for LARC. The nodal down-staging of MAC was relatively lower than that of AC, although the differences were not statistically significant.

Histogram analysis based on intravoxel incoherent motion diffusion-weighted imaging for determining the perineural invasion status of rectal cancer.

Background: Unfortunately, the morphologic magnetic resonance imaging (MRI) is unable to determine perineural invasion (PNI) status. This study applied histogram analysis of intravoxel incoherent motion diffusion-weighted imaging (IVIM-DWI) in the assessment of PNI status of rectal cancer (RC). Methods: The retrospective analysis enrolled 175 patients with RC confirmed by postoperative pathology in The First Affiliated Hospital of Shandong First Medical University from January 2019 to December 2021. All patients underwent preoperative rectal MRI. Whole-tumor volume histogram features from IVIM-DWI were extracted using open-source software. Univariate analysis and multivariate logistic regression analysis were used to compare the differences in histogram parameters and clinical features between the PNI-positive group and PNI-negative group. Receiver operating characteristic curve analysis was used to evaluate the diagnostic performance, while the Delong test was used to compare the area under the curve of the models. Results: The interobserver agreement of the histogram features derived from DWI, including apparent diffusion coefficient (ADC), true diffusion coefficient (D), pseudo-diffusion coefficient (D*), perfusion fraction (f), water molecular diffusion heterogeneity index (α), and distributed diffusion coefficient (DDC) were good to excellent. A total of eight histogram features including DWI_maximum, DWI_skewness, D_kurtosis, D_minimum, D_skewness, D*_energy, D*_skewness, and f_minimum were significantly different between the PNI-positive and PNI-negative groups in the univariate analysis (P<0.05); among the clinicoradiologic factors, percentage of rectal wall circumference invasion (PCI) was significantly different between the two groups (P<0.05). Multivariate analysis demonstrated that the values of D*_energy, D*_skewness, and f_minimum differed significantly between the PNI-positive patients and PNI-negative patients (P<0.05), with the independent risk factors being D*_skewness [odds ratio (OR) =1.157; 95% confidence interval (CI): 1.050-1.276; P=0.003] and PCI (OR =11.108, 95% CI: 1.767-69.838; P=0.0002). The area under the curve of the model combining the three histogram features and PCI to assess PNI status in RC was 0.807 (95% CI: 0.741-0.863). The results of the Delong test showed that the combined model was significantly different from each single-parameter model (P<0.05). Conclusions: The combined model constructed on the basis of IVIM-DWI histogram features may help to assess the status of RC PNI.

Current landscape of gastrointestinal radiation oncology in Spain: a multicenter real-life survey and comparison with key clinical guidelines.

Background: The GI Tumors Workgroup, a division of the Spanish Society of Radiation Therapy, conducted a survey in December 2020 to assess the adherence of radiation oncologists in Spain to international guidelines for gastrointestinal tumors. Materials and methods: Using Google Forms, we designed a survey covering treatments for esophageal, gastric, pancreatic, and rectal cancers. Results: In esophageal cancer treatment, neoadjuvant chemoradiation was the standard in 76.7% of institutions. Radiation doses range from 41.1 to 50.4 Gy in conventional fractionation. Planning positron emission tomography-computed tomography (PET-CT) was performed in 83.3% of centers, and intensity-modulated radiation therapy/volumetric-arc radiation therapy (IMRT/VMAT) was the preferred technique in 86.7% of institutions. For gastric cancer, 71.4% followed perioperative chemotherapy guidelines. In the case of adjuvant radiotherapy, the majority prescribed 45-50.4 Gy, and 82.1% used IMRT/VMAT for treatment. For pancreas cancer, neoadjuvant chemotherapy followed by surgery in borderline resectable tumors and induction chemotherapy followed by radical radiotherapy for non-resectable tumors were the most frequent approaches. IMRT/VMAT was the primary technique. Locally advanced rectal cancer treatment is mainly based on neoadjuvant radiotherapy in all institutions. The preferred radiation doses typically range from 45 to 50 Gy in conventional fractionation. IMRT/VMAT was standard in most Institutions. Conclusions: Spain's radiotherapy practices among respondents generally align with international guidelines for GI tumors highlighting Spain's commitment to evidence-based medical practice.

Genetic parameters for pelvic organ prolapse in purebred and crossbred sows.

This study aimed to investigate genetic parameters for sow pelvic organ prolapse in purebred and crossbred herds. Pelvic organ prolapse was recorded as normal or prolapsed on the individual sow level across 32 purebred and 8 crossbred farms. In total, 75,162 purebred Landrace sows from a single maternal line were recorded between 2018 and 2023, while 18,988 commercial two-way crossbred (Landrace x Large White) sows were available between 2020 and 2023. There were 5,122,005 animals included in the pedigree. The prolapse in purebreds and crossbreds was considered two different traits in the model. Pedigrees of the crossbred sows were determined based on genotypes through parentage assignment. The average incidence rates were 1.81% and 3.93% for purebreds and crossbreds, respectively. The bivariate model incorporated fixed effects of parity group and region with random effects of contemporary group (farm and mating year and month at the first parity), additive genetic, and residual. Genetic parameter estimates were obtained using BLUPF90+ with the AIREML option. The estimated additive variance was larger in crossbreds than in purebreds. Estimates of heritability in the observed scale were 0.09 (0.006) for purebreds and 0.11 (0.014) for crossbreds, with a genetic correlation of 0.83 using a linear model. Results suggested that including data from crossbreds with higher incidence rate is beneficial and selection to reduce the prolapse incidence in purebred sow herds would also benefit commercial crossbred sow herds.

Epidemiology of Colorectal Cancer in Saudi Arabia: A Review.

Colorectal cancer (CRC) is the second leading cause of cancer death in the world, originating from the glandular epithelial cells of the large intestine and the rectum. This article aims to review the epidemiology of CRC in Saudi Arabia, focusing on prevalence, incidence, risk factors, preventive measures, and outcomes. This narrative review utilized the PubMed database for data extraction, including freely accessible studies published in the last 15 years. Sixteen articles from different study designs were included, while awareness and non-English language studies were excluded. In 2020, the incidence and mortality rate of CRC in Saudi Arabia were 14.6% and 1.48% among all cancers, respectively. From 2006 to 2016, the number of colon cancer and rectal cancer cases increased by 8% and 7%, respectively. Risk factors for CRC in Saudi Arabia include low education level, unemployment, physical inactivity, excess weight, poor knowledge of foods rich in fiber, cigarette smoking, reduced serum vitamin D and calcium levels, and certain gene mutations. National guidelines in Saudi Arabia recommend CRC screening for all individuals above 45 years using colonoscopy, flexible sigmoidoscopy, or fecal occult blood test. The 10-year survival rate for CRC in Saudi Arabia is 44.6%. The overall 5-year survival rate for the Ministry of National Guard-Health Affairs is 52.0%. To lower the incidence and mortality of CRC, primary, secondary, and tertiary prevention are all very important. The most crucial aspect is to concentrate on primary prevention, which may involve raising public awareness of CRC risk factors and strategies for reducing or eliminating them.

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.

Meta-analysis of the correlation between high expression of lncRNA NEAT1 in rectal cancer and pathological features and prognosis.

Background: To systematically evaluate the relationship between the expression level of long noncoding RNA NEAT1 and the clinical characteristics and prognostic value of rectal cancer patients. Methods: PubMed, EMBASE, Cochrane library database and case-control studies on the correlation between abnormal expression of lncRNA NEAT1 and prognosis of rectal cancer patients published by the American clinical trials registry before May 1, 2023 were searched. The search time was from the establishment of the database to May 30, 2023. Results: A total of 7 case-control studies were included, including 1063 cancer patients. The results of meta-analysis showed that the high expression of lncRNA NEAT1 was significantly correlated with the degree of differentiation [or=0.45, 95%CI=0.32-0.63, P<0.01], tumor size [or=0.59, 95%CI=0.42-0.82, P<0.01], and overall survival [HR=1.34, 95%CI=1.21-1.48, P<0.001]; However, it was not associated with gender [or=1.23, 95%CI= 0.88-1.72, P=0.23] and lymph node metastasis [or=0.87, 95%CI=0.45-1.66, P=0.67]. Conclusions: The high expression of lncRNA NEAT1 may be a risk factor for poor prognosis in patients with malignant tumors, and lncRNA NEAT1 can be used as a potential biomarker to evaluate its prognosis.

Pathological prognostic factors of rectal cancer based on diffusion-weighted imaging, intravoxel incoherent motion, and diffusion kurtosis imaging.

OBJECTIVES: To explore diffusion-weighted imaging (DWI), intravoxel incoherent motion (IVIM), and diffusion kurtosis imaging (DKI) for assessing pathological prognostic factors in patients with rectal cancer. MATERIALS AND METHODS: A total of 162 patients (105 males; mean age of 61.8 ± 13.1 years old) scheduled to undergo radical surgery were enrolled in this prospective study. The pathological prognostic factors included histological differentiation, lymph node metastasis (LNM), and extramural vascular invasion (EMVI). The DWI, IVIM, and DKI parameters were obtained and correlated with prognostic factors using univariable and multivariable logistic regression. Their assessment value was evaluated using receiver operating characteristic (ROC) curve analysis. RESULTS: Multivariable logistic regression analyses showed that higher mean kurtosis (MK) (odds ratio (OR) = 194.931, p < 0.001) and lower apparent diffusion coefficient (ADC) (OR = 0.077, p = 0.025) were independently associated with poorer differentiation tumors. Higher perfusion fraction (f) (OR = 575.707, p = 0.023) and higher MK (OR = 173.559, p < 0.001) were independently associated with LNMs. Higher f (OR = 1036.116, p = 0.024), higher MK (OR = 253.629, p < 0.001), lower mean diffusivity (MD) (OR = 0.125, p = 0.038), and lower ADC (OR = 0.094, p = 0.022) were independently associated with EMVI. The area under the ROC curve (AUC) of MK for histological differentiation was significantly higher than ADC (0.771 vs. 0.638, p = 0.035). The AUC of MK for LNM positivity was higher than f (0.770 vs. 0.656, p = 0.048). The AUC of MK combined with MD (0.790) was the highest among f (0.663), MK (0.779), MD (0.617), and ADC (0.610) in assessing EMVI. CONCLUSION: The DKI parameters may be used as imaging biomarkers to assess pathological prognostic factors of rectal cancer before surgery. CLINICAL RELEVANCE STATEMENT: Diffusion kurtosis imaging (DKI) parameters, particularly mean kurtosis (MK), are promising biomarkers for assessing histological differentiation, lymph node metastasis, and extramural vascular invasion of rectal cancer. These findings suggest DKI's potential in the preoperative assessment of rectal cancer. KEY POINTS: Mean kurtosis outperformed the apparent diffusion coefficient in assessing histological differentiation in resectable rectal cancer. Perfusion fraction and mean kurtosis are independent indicators for assessing lymph node metastasis in rectal cancer. Mean kurtosis and mean diffusivity demonstrated superior accuracy in assessing extramural vascular invasion.

Effects on anorectal function of endoscopic submucosal dissection for rectal tumors involving the dentate line.

OBJECTIVE: Endoscopic submucosal dissection (ESD) is a specific procedure that uses an electrosurgical knife for en-bloc resectioning large tumors. However, no study has examined the effect of ESD on the defecation function of patients with rectal tumors. We aimed to investigate the potential effects caused by ESD by analyzing changes in the morphology and movement of the anorectum pre- and post-ESD. METHODS: This prospective observational study included 11 patients with anorectal tumors who underwent ESD between April 2020 and February 2022. Pre-ESD assessments included anorectal manometry and defecography. Post-ESD assessments were conducted 2 months later, including anorectal manometry, defecography, and proctoscopy for ulcer and stenosis evaluation. RESULTS: The median patient age was 73 years, including seven males and four females. Eight patients (73%) had a tumor in the lower rectum, and the extent of resection was less than 50% of the rectal lumen. Resection reached the dentate line in six cases (55%). In the patients with post-ESD mucosal defects involving the dentate line, the median of functional anal canal length significantly decreased from (3.4 cm pre-ESD to 2.8 cm post-ESD, p = 0.04). Defecography revealed one case with incomplete evacuation (<50%) and incontinence post-ESD. Interestingly, patients with pre-existing rectoceles noted resolution of lesions post-ESD. None of the patients reported daily constipation or fecal incontinence. CONCLUSIONS: While rectal ESD is unlikely to cause significant real-world defecation difficulties, alterations in rectal and anal canal morphology and function may occur if the dentate line is involved in the resection range.

Prediction of postoperative complications following transanal total mesorectal excision in middle and low rectal cancer: development and internal validation of a clinical prediction model.

PURPOSE: The objective of this study is to develop a nomogram for the personalized prediction of postoperative complication risks in patients with middle and low rectal cancer who are undergoing transanal total mesorectal excision (taTME). This tool aims to assist clinicians in early identification of high-risk patients and in addressing preoperative risk factors to enhance surgical safety. METHODS: In this case-control study, 207 patients diagnosed with middle and low rectal cancer and undergoing taTME between February 2018 and November 2023 at The First Affiliated Hospital of Xiamen University were included. Independent risk factors for postoperative complications were analyzed using the Least Absolute Shrinkage and Selection Operator (LASSO) regression and multifactorial logistic regression models. A predictive nomogram was constructed using R Studio. RESULTS: Among the 207 patients, 57 (27.5%) experienced postoperative complications. The LASSO and multifactorial logistic regression analyses identified operation time (OR = 1.010, P = 0.007), smoking history (OR = 9.693, P < 0.001), anastomotic technique (OR = 0.260, P = 0.004), and ASA score (OR = 9.077, P = 0.051) as significant predictors. These factors were integrated into the nomogram. The model's accuracy was validated through receiver operating characteristic curves, calibration curves, consistency indices, and decision curve analysis. CONCLUSION: The developed nomogram, incorporating operation time, smoking history, anastomotic technique, and ASA score, effectively forecasts postoperative complication risks in taTME procedures. It is a valuable tool for clinicians to identify patients at heightened risk and initiate timely interventions, ultimately improving patient outcomes.

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.

Assessment of prognostic indicators and KRAS mutations in rectal cancer using a fractional-order calculus MR diffusion model: whole tumor histogram analysis.

PURPOSE: This study aims to explore the relationship between apparent diffusion coefficient (ADC) and fractional-order calculus (FROC)-specific parameters with prognostic indicators and Kirsten rat sarcoma viral oncogene homologue (KRAS) mutation status in rectal cancer. METHODS: One hundred fifty-eight patients with rectal cancer were retrospectively enrolled. Histogram measurements of ADC, diffusion coefficient (D), intravoxel diffusion heterogeneity (ß), and a microstructural quantity (µ) were estimated for the whole-tumor volume. The relationships between histogram measurements and prognostic indicators were evaluated. The efficacy of histogram measurements, both conducted singly and in conjunction, for evaluating different KRAS mutation statuses was also assessed. The performance of mean and median histogram measurements in evaluating various KRAS mutation statuses was assessed using Receiver Operating Characteristic (ROC) curve analysis. A p-value of less than 0.05 was considered statistically significant. RESULTS: The histogram measurements of ADC, D, ß, and µ differed significantly between well-moderately differentiated groups and poorly differentiated groups, T1-2 and T3-4 subgroups, lymph node metastasis (LNM)-negative and LNM-positive subgroups, extranodal extension (ENE)-negative and ENE-positive subgroups, tumor deposit (TD)-negative and TD-positive subgroups, and lymphovascular invasion (LVI)-negative and LVI-positive subgroups. The combination of Dmean, ßmean, and µmean achieved the highest performance [The area under the ROC curve (AUC) = 0.904] in evaluating the KRAS mutation status. CONCLUSION: When assessing parameters from the FROC model as potential biomarkers through histograms, they surpass traditional ADC values in distinguishing prognostic indicators and determining KRAS mutation status in rectal cancer.

Different impacts of adipose tissue dynamics on prognosis in patients with resectable locally advanced rectal cancer treated with and without neoadjuvant treatment.

Background: Body composition is recognized to be associated with clinical outcomes in patients with locally advanced rectal cancer (LARC). This study aimed to determine the prognostic role of regional adipose tissue distribution in patients with resectable LARC treated with or without neoadjuvant chemoradiotherapy (nCRT). Methods: This retrospective study included 281 consecutive patients who underwent radical surgery for LARC with or without preoperative nCRT between 2013 and 2019. Patients underwent contrast-enhanced CT scans before nCRT and before surgery. Visceral adipose tissue (VAT), abdominal subcutaneous adipose tissue (aSAT), and gluteal subcutaneous adipose tissue (gSAT) were quantified on the CT images. The association of adipose tissue distribution with progression-free survival (PFS) was analyzed using Cox proportional hazards analysis. Results: A total of 102 nCRT-treated and 179 primarily resected patients were included. During a median follow-up period of 24 months, 74 (26.3%) patients experienced local recurrence or metastasis. Multivariable analysis showed that VAT was associated with PFS in all patients (hazard ratio [HR] 1.28, 95% confidence interval [CI] 1.04-1.57; P = 0.021). This association was only maintained in primarily resected patients (HR 1.31, 95% CI 1.02-1.69; P = 0.037). For patients receiving preoperative nCRT, VAT was not significantly associated with PFS, while the dynamic change in gSAT (ΔgSAT) between nCRT and surgery was associated with PFS (HR 0.43, 95%CI 0.27-0.69, P = 0.001). Conclusion: Visceral obesity is an adverse prognostic factor in patients with resectable LARC treated by primary resection, while increased gluteal subcutaneous adiposity during preoperative nCRT may indicate favorable clinical outcomes.

Postoperative urinary retention following transanal versus laparoscopic total mesorectal excision for rectal cancer: A randomized trial report from an experienced center.

Background: Transanal total mesorectal excision has emerged as a potential solution to certain limitations associated with laparoscopic total mesorectal excision in rectal cancer patients. Differences in surgical approaches have raised questions regarding their impact on the risk of postoperative urinary retention, with limited data available from large scale randomized clinical study. Objective: To report incidence of postoperative urinary retention and evaluate the associated risk factors for transanal total mesorectal excision. Design: In this randomized controlled trial (ClinicalTrials. gov NCT06147492), we retrieved 524 patients who received total mesorectal excision (TME) for stage I-III rectal cancer between June 2019 and April 2022, and the patients were randomly assigned in a 1:1 ratio to undergo either taTME or laTME. Patients: We enrolled 524 patients who underwent total mesorectal excision for stage I-III rectal cancer between June 2019 and April 2022. Main outcome measures: The incidence of postoperative urinary retention. Results: Among the 524 enrolled patients, 261 were randomized to the laTME group, while 263 were were randomized the taTME group. The median age was 58 years, and 340 participants (64.8 %) were male. Notably, 37 individuals (7.0 %) experienced postoperative urinary retention during the follow-up period, with no significant disparity was observed between the taTME and laTME groups (6.8 % and 7.2 %, respectively, P = 0.98). Risk factors associated with PUR in patients following taTME encompassed early removal of the urinary catheter (P = 0.006), net infusion rate >4.09 ml kg-1.h-1 (P = 0.006), and an age surpassing 65 years (P = 0.0321). Limitations: The generalizability of the findings outside specialist rectal cancer centers may be limited. Conclusions: Transanal total mesorectal excision was not found to heighten the risk of postoperative urinary retention. Nonetheless, it is advisable removing postoperative catheter beyond the initial day and exercising caution in the administration of intravenous fluids in clinical practice for taTME procedures.

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

BACKGROUND: LARC patients commonly receive adjuvant therapy, however, hidden micrometastases still limit the improvement of OS. This study aims to investigate the impact of VASN in rectal cancer with pulmonary metastasis and understand the underlying molecular mechanisms to guide adjuvant chemotherapy selection. METHODS: Sequencing data from rectal cancer patients with pulmonary metastasis from Sun Yat-sen University Cancer Center (SYSUCC) and publicly available data were meticulously analyzed. The functional role of VASN in pulmonary metastasis was validated in vivo and in vitro. Coimmunoprecipitation (co-IP), immunofluorescence, and rescue experiments were conducted to unravel potential molecular mechanisms of VASN. Moreover, VASN expression levels in tumor samples were examined and analyzed for their correlations with pulmonary metastasis status, tumor stage, adjuvant chemotherapy benefit, and survival outcome. RESULTS: Our study revealed a significant association between high VASN expression and pulmonary metastasis in LARC patients. Experiments in vitro and in vivo demonstrated that VASN could promote the cell proliferation, metastasis, and drug resistance of colorectal cancer. Mechanistically, VASN interacts with the NOTCH1 protein, leading to concurrent activation of the NOTCH and MAPK pathways. Clinically, pulmonary metastasis and advanced tumor stage were observed in 90% of VASN-positive patients and 53.5% of VASN-high patients, respectively, and VASN-high patients had a lower five-year survival rate than VASN-low patients (26.7% vs. 83.7%). Moreover, the Cox analysis and OS analysis indicated that VASN was an independent prognostic factor for OS (HR = 7.4, P value < 0.001) and a predictor of adjuvant therapy efficacy in rectal cancer. CONCLUSIONS: Our study highlights the role of VASN in decreasing drug sensitivity and activating the NOTCH and MAPK pathways, which leads to tumorigenesis and pulmonary metastasis. Both experimental and clinical data support that rectal cancer patients with VASN overexpression detected in biopsies have a higher risk of pulmonary metastasis and adjuvant chemotherapy resistance.

Diagnosis of Hirschsprung disease by analyzing acetylcholinesterase staining using artificial intelligence.

OBJECTIVES: Classical Hirschsprung disease (HD) is defined by the absence of ganglion cells in the rectosigmoid colon. The diagnosis is made from rectal biopsy, which reveals the aganglionosis and the presence of cholinergic hyperinnervation. However, depending on the method of rectal biopsy, the quality of the specimens and the related diagnostic accuracy varies substantially. To facilitate and objectify the diagnosis of HD, we investigated whether software-based identification of cholinergic hyperinnervation in digitalized histopathology slides is suitable for distinguishing healthy individuals from affected individuals. METHODS: N = 190 samples of 112 patients who underwent open surgical rectal biopsy at our pediatric surgery center between 2009 and 2019 were included in this study. Acetylcholinesterase (AChE) stained slides of these samples were collected and digitalized via slide scanning and analyzed using two digital imaging software programs (HALO, QuPath). The AChE-positive staining area in the mucosal layers of the intestinal wall was determined. In the next step machine learning was employed to identify patterns of cholinergic hyperinnervation. RESULTS: The area of AChE-positive staining was greater in HD patients compared to healthy individuals (p < 0.0001). Artificial intelligence-based assessment of parasympathetic hyperinnervation identified Hirschsprung disease with a high precision (area under the curve [AUC] 0.96). The accuracy of the prediction model increased when nonrectal samples were excluded (AUC 0.993). CONCLUSIONS: Software-assisted machine-learning analysis of AChE staining is suitable to improve the diagnostic accuracy of Hirschsprung disease.

Is centralization for rectal cancer surgery necessary?

Rectal cancer surgery is complex and more technically challenging than colonic surgery. Over the last 30 years internationally, there has been a growing impetus for centralizing care to improve outcomes for rectal cancer. Centralizing care may potentially reduce variations of care, increase standardization and compliance with clinical practice guidelines. However, there are barriers to implementation at a professional, political, governance and resource allocation level. Centralization may increase inequalities to accessing healthcare, particularly impacting socioeconomically disadvantaged and rural populations with difficulties to commuting longer distances to "centres of excellence". Furthermore, it is unclear if centralization actually improves outcomes. Recent studies demonstrate that individual surgeon volume rather than hospital volume may be more important in achieving optimal outcomes. In this review, we examine the literature to assess the value of centralization for rectal cancer surgery.

Prognostic factors for local recurrence in patients with rectal cancer submitted to neoadjuvant chemoradiotherapy and total mesorectal excision.

Prognostic factors for local recurrence in patients with rectal cancer submitted to neoadjuvant chemoradiotherapy and total mesorectal excision. BACKGROUND: The standard curative treatment for locally advanced rectal cancer of the middle and lower thirds is long-course chemoradiotherapy followed by total mesorectal excision. PURPOSE: To evaluate the prognostic factors associated with local recurrence in patients with rectal cancer submitted to neoadjuvant chemoradiotherapy and total mesorectal excision. METHODS: Retrospective study including patients with rectal cancer T3-4N0M0 or T (any)N + M0 located within 10 cm from the anal border, or patients with T2N0M0 located within 5 cm, treated by long course chemoradiotherapy followed by total mesorectal excision with curative intent. Clinical, demographic, radiologic, surgical, and anatomopathological data were collected. Local recurrence was estimated using the Kaplan-Meier function, and risk was estimated according to each characteristic using univariate and multivariate analyses. RESULTS: 270 patients were included, 57.8% male and mean age 61.7 (30‒88) years. At initial staging, 6.7% of patients were stage I, 21.5% stage II, and 71.8% stage III. Open surgery was performed in 65.2%, with sphincter preservation in 78.1%. Mortality within 30 postoperative days was 0.7%. After 49.4 (0.5‒86.1) months of median follow-up, overall and local recurrences were 26.3% and 5.9%. On multivariate analyses, local recurrence was associated with involvement of the mesorectal fascia on restaging MRI (HR = 9.11, p = 0.001) and with pathologic involvement of radial surgical margin (HR = 8.19, p < 0.001). CONCLUSION: Local recurrence of rectal cancer treated with long-course chemoradiation and total mesorectal excision is low and is associated with pathologic involvement of the radial surgical margin and can be predicted on restaging MRI.