Rectal Cancer Patients Research Articles

Unraveling the role of computed tomography derived body composition metrics on anastomotic leakages rates in rectal cancer surgery: A protocol for a systematic review and meta-analysis.

Anastomotic leakage is a major concern following total mesorectal excision for rectal cancer, affecting oncological outcomes, morbidity an treatment costs. Body composition has been suggested to influence anastomotic leakage rates. However, literature on how body composition impact anastomotic leakage rates is conflicting. This systematic review aims to evaluate the role of computed tomography derived body composition metrics on anastomotic leakage rates in rectal cancer patients. Databases PubMed/MEDLINE, Cochrane Library, web of science, and EMBASE, will be systematically searched for papers from January 2010 onwards. Study selection, data collection and quality assessment will be independently performed by three research fellows. Outcomes described in three or more studies will be included in the meta-analysis. The Q-test and I2 statistic will be used to assess statistical heterogeneity between studies. Publication bias will be examined by visual inspection of funnel plots and quantified by Egger's test. Sensitivity analyses will be conducted to examine the robustness of the meta-analysis. Reporting of the findings will be in line with the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines. This systematic review will synthesize the current evidence and will identify knowledge gaps. Results of the systematic review will aid health care professional in pre-operative decision making and will be distributed through a peer-reviewed publication and presentation of results at international meetings. PROSPERO protocol number: CRD42023471537.

Does computed tomography-derived volumometry and densitometry of psoas muscle really correlate with complications in rectal cancer patients after elective surgery?

Although sarcopenia is recognized as one of the risk factors for increased morbidity after resection for colorectal cancer, the question of the most appropriate way to identify and quantify it is still unresolved. This is a retrospective unicentric study following patients undergoing elective resection of the rectum for carcinoma with available staging computed tomography (CT) of the trunk. Psoas muscle density (PMD) and its area relative to patient height psoas muscle index (PMI) at the level of inferior vertebral end plate of third lumbar vertebra (L3) were assessed using an initial staging CT scan of the trunk. Post-operative complications, evaluated according to the Clavien-Dindo classification, and blood samples on post-operative days (POD) 3 and 5 were also recorded in the study population. Patients were divided into groups with complicated and uncomplicated post-operative course, and observed parameters were then statistically compared. The correlation of PMI values with the development of post-operative complications was not confirmed in a data set of 206 patients. PMD values were found to be borderline statistically significant in patients with complicated post-operative course, while in the group of patients with severe complications (Clavien-Dindo III-IV), there was no statistically significant difference in PMI or PMD values. The same results were obtained when comparing patients with anastomotic leak (AL). It was confirmed that operations on the lower rectum are riskier for the development of post-operative complications. The secondary objective of our study regarding serum C-reactive protein (CRP) levels of 3rd and 5th POD gave us the answer in the form of cutoff values of 115.7 mg/L (3rd POD) and 76 mg/L (5th POD). PMD appears to be a promising tool for predicting post-operative morbidity in patients after rectal resection, but a clear consensus on the method of measurement, interpretation of results and cutoff values is needed. Lower rectal resections are burdened with a higher risk of post-operative complications, especially AL. Monitoring of CRP levels remains an important marker in the prediction of AL due to its negative predictive value.

PD-L1 Expression in Paired Samples of Rectal Cancer.

Immune checkpoint inhibitors and immune-related biomarkers are increasingly investigated in rectal cancer (RC). We retrospectively analysed PD-L1 expression in diagnostic biopsy and resection samples from RC patients treated at our centre between 2000 and 2020. PD-L1 immunostaining (22C3 clone) was evaluated according to tumour proportion (TPS), immune cell (ICS), and the combined positive score (CPS). Eighty-three patients were included. At diagnosis, PD-L1 expression ≥1%/≥5% was observed in 15.4%/0%, 80.7%/37.4%, and 69.2%/25.6% of patients based on TPS, ICS, and CPS, respectively. At surgery, the respective figures were 4.6%/1.5%, 60.2%/32.5%, and 50.7%/26.2%. Using the 1% cut-off and regardless of the scoring system, PD-L1 was less expressed in surgery than biopsy samples (p ≤ 0.04). In paired specimens, PD-L1-ICS reduction was especially observed following neoadjuvant long-course (chemo)radiotherapy (p = 0.03). PD-L1-ICS of ≥5% in surgical samples (HR: 0.17; p = 0.02), and a biopsy-to-surgery increase in PD-L1-ICS (HR: 0.19; p = 0.04) was predictive for longer disease-free survival, while the PD-L1-ICS of either ≥1% (HR 0.28; p = 0.04) or ≥5% (HR 0.19; p = 0.03) in surgical samples and the biopsy-to-surgery increase in PD-L1-ICS (HR: 0.20; p = 0.04) were associated with better overall survival. Our study suggests that PD-L1 expression in RC is largely reflective of immune cell infiltration, and its presence/increase in surgical samples predicts better outcomes.

Magnetic resonance imaging radiomics-based prediction of severe inflammatory response in locally advanced rectal cancer patients after neoadjuvant radiochemotherapy.

To predict severe inflammatory response after neoadjuvant radiochemotherapy in locally advanced rectal cancer (RC) patients using magnetic resonance imaging (MRI) radiomics models. This retrospective study included patients who underwent radical surgery for RC cancer after neoadjuvant radiochemotherapy between July 2017 and December 2019 at XXX Hospital. MRI radiomics features were extracted from T2WI images before (pre-nRCT-RF) and after (post-nRCT-RF) neoadjuvant radiochemotherapy, and the variation of radiomics features before and after neoadjuvant radiochemotherapy (delta-RF) were calculated. Eight, eight, and five most relevant features were identified for pre-nRCT-RF, post-nRCT-RF, and delta-RF, respectively. Eighty-six patients were included and randomized 3:1 to the training and test set (n = 65 and n = 21, respectively). The prediction model based on delta-RF had areas under the curve (AUCs) of 0.80 and 0.85 in the training and test set, respectively. A higher rate of difficult operations was observed in patients with severe inflammation (65.5% vs. 42.9%, P = 0.045). The prediction model based on MRI delta-RF may be a useful tool for predicting severe inflammatory response after neoadjuvant radiochemotherapy in locally advanced RC patients.

Tumor Vessel Normalization via PFKFB3 Inhibition Alleviates Hypoxia and Increases Tumor Necrosis in Rectal Cancer upon Radiotherapy.

Novel therapies to better treat colorectal cancer are necessary to improve patient outcomes. Therefore, in this study, we evaluated the combination of a metabolic inhibitor (3PO) and standard radiotherapy in different experimental settings. We have observed that the addition of 3PO increased radiation effects, ultimately improving tumor cell response to therapy.

The Norwegian Watch and Wait study: Norwait for rectal cancer. A report from a failed study-a word of caution.

The paucity of prospective data on the subject of Watch and Wait for rectal cancer prompted the implementation of Norwait, a population-based study including rectal cancer patients after neoadjuvant therapy. The aim of the study was to assess the accuracy of clinical complete response (cCR) and quantify the regrowth rates. Norwait was a prospective population-based observational study with ethical approval (2017/935) registered at clinicaltrials.com (NTC03402477). Residents of Norway with histologically proven rectal cancer located within 15cm from anal verge were eligible following completion of radiotherapy or chemoradiation at seven hospitals. cCR was the disappearance of tumour and of any ulcer with/without the appearance of whitening of prior tumour site and telangiectasia evaluated at 12weeks by digital rectal exam, and endoscopic imaging. The study aimed to include 100 cCR patients with regrowth rates as primary endpoint. The data are presented in crude form. Eighty-two patients were included in seven hospitals from 2018 to 2020 when the study was terminated. Fifty-one patients were included in six hospitals, whereas protocol violations were identified in one hospital, where thirty-one (rather than protocol-estimated 12) patients were enrolled. Amongst the 31 patients, there were only 2 with documented cCR. Of the latter 29, there were 16 with ulcer or persistent tumour, and 13 without any documentation of cCR. Of these, 23 underwent surgery with a delay up to 50weeks. At median 54-month follow-up of 31 patients, there were 77% local regrowths (n = 23), 40% metachronous metastases (n = 12) and 23% deaths (n = 7). At median 54-month follow-up of 51 cCR patients, there were 53% local regrowths (n = 27), 14% metachronous metastases (n = 7) and 4% deaths (n = 2). Norwait admonishes a word of caution reaching beyond the inconclusive results of a population-based study jeopardised by serious violation to protocol and legislation for conducting safe research.

Does aortic calcification really affect anastomotic leakage after rectal cancer surgery?

The purpose of the current study was to analyze whether aortic calcification had impact on the anastomotic leakage (AL) after rectal cancer (RC) surgery. We collected patients' information from January 2011 to January 2020 in a single teaching hospital. Preoperative computed tomography images were obtained. Abdominal aortic calcification (AAC), superior mesenteric aortic calcification, and inferior mesenteric aortic calcification were recorded. The difference of AL and grade C AL was calculated. A total of 2412 RC patients were included in this study. Ninety-seven (4.0%) RC patients experienced AL and 47 (1.9%) RC patients experienced grade C AL. The amount of AAC, superior mesenteric aortic calcification, and inferior mesenteric aortic calcification was 1546 (64.1%), 128 (5.3%), and 31 (1.3%). The AL group had higher portion of AAC (P = .019) than the no AL group, and the grade C AL group had higher portion of AAC (P = .016) than the no grade C AL group. In univariate logistic regression analysis, AAC was a significant potential factor for AL (P = .021, OR = 1.739, 95% CI = 1.088-2.779) and grade C AL (P = .019, OR = 2.339, 95% CI = 1.115-4.986). However, in multivariate logistic regression, AAC was not an independent predictive factor for AL (P = .157, OR = 1.443, 95% CI = 0.871-2.358) or grade C AL (P = .064, OR = 2.055, 95% CI = 0.960-4.399). AAC was associated with higher amount of AL and grade C AL, however, AAC was not an independent predictive factor for AL or grade C AL.

Decision-making preferences and regret in rectal cancer patients undergoing restorative proctectomy: A prospective cohort study

BackgroundHow patients make treatment choices in rectal cancer is poorly understood and may affect long-term regret and satisfaction. The objective of this study is to characterize decision-making preferences and their effect on decisional regret in patients undergoing restorative proctectomy for rectal cancer. MethodsA prospective cohort study was conducted in a single academic specialist rectal cancer center from October 2018 to June 2022. Adult patients who underwent restorative proctectomy at least one year prior were recruited. Health literacy was assessed using the BRIEF instrument. Decision-making preferences regarding cancer treatment were assessed using the Control Preferences Scale. Decisional regret regarding their choice of restorative proctectomy was assessed using the Decision Regret Score. Bowel dysfunction was measured using the low anterior resection syndrome score. ResultsOverall, 123 patients were included. Health literacy was categorized as adequate in 63%, marginal in 25%, and limited in 12%. Patients with adequate health literacy were more likely to prefer a collaborative decision-making role compared with those with low health literacy (86% vs 65%, P = .016). Patients with incongruence between preferred and actual decision-making roles were more likely to report high regret (56% vs 25%, P = .003). Patients with major low anterior resection syndrome were also more likely to experience high regret compared with patients with no/minor low anterior resection syndrome (44% vs 25%, P = .036). ConclusionA significant proportion of patients with rectal cancer undergoing restorative proctectomy do not have a decision-making role that is congruent with their preferences, and these patients experience a high degree of regret.

Synthetic CT generation for pelvic cases based on deep learning in multi-center datasets

Background and purposeTo investigate the feasibility of synthesizing computed tomography (CT) images from magnetic resonance (MR) images in multi-center datasets using generative adversarial networks (GANs) for rectal cancer MR-only radiotherapy.Materials and methodsConventional T2-weighted MR and CT images were acquired from 90 rectal cancer patients at Peking University People’s Hospital and 19 patients in public datasets. This study proposed a new model combining contrastive learning loss and consistency regularization loss to enhance the generalization of model for multi-center pelvic MRI-to-CT synthesis. The CT-to-sCT image similarity was evaluated by computing the mean absolute error (MAE), peak signal-to-noise ratio (SNRpeak), structural similarity index (SSIM) and Generalization Performance (GP). The dosimetric accuracy of synthetic CT was verified against CT-based dose distributions for the photon plan. Relative dose differences in the planning target volume and organs at risk were computed.ResultsOur model presented excellent generalization with a GP of 0.911 on unseen datasets and outperformed the plain CycleGAN, where MAE decreased from 47.129 to 42.344, SNRpeak improved from 25.167 to 26.979, SSIM increased from 0.978 to 0.992. The dosimetric analysis demonstrated that most of the relative differences in dose and volume histogram (DVH) indicators between synthetic CT and real CT were less than 1%.ConclusionThe proposed model can generate accurate synthetic CT in multi-center datasets from T2w-MR images. Most dosimetric differences were within clinically acceptable criteria for photon radiotherapy, demonstrating the feasibility of an MRI-only workflow for patients with rectal cancer.

Total neoadjuvant therapy with mFOLFIRINOX versus preoperative chemoradiotherapy in patients with locally advanced rectal cancer: long-term results of the UNICANCER-PRODIGE 23 trial

The standard of care for the treatment of locally advanced rectal cancer (LARC) results in an excellent local disease control but the metastasis rates remain high. PRODIGE 23 demonstrated improved disease-free survival (DFS) and metastasis-free survival (MFS) with total neoadjuvant therapy versus standard of care in this population. Long-term analysis of overall survival (OS) is reported here. The study design, participants, and primary endpoint DFS have been reported for this multicenter, randomized, open-label, phase III trial investigating the neoadjuvant chemotherapy with mFOLFIRINOX (6 cycles) followed by chemoradiotherapy, surgery, and adjuvant chemotherapy (6 cycles), versus chemoradiotherapy, surgery, and adjuvant chemotherapy (12 cycles) in patients with locally advanced rectal adenocarcinoma under peritoneal reflection on magnetic resonance imaging, and staged cT3/T4. Key secondary endpoints included OS, MFS, and local and metastatic recurrence rate. With a median follow-up of 82.2 months, the 7-year DFS was 67.6% [95% confidence interval (CI) 60.7% to 73.9%] and 62.5% (95% CI 55.6% to 68.6%) [restricted mean survival time (RMST) difference 5.73 months, 95% CI 0.05-11.41 months, P= 0.048] in the neoadjuvant chemotherapy and the standard-of-care groups, respectively. The 7-year MFS was 79.2% (95% CI 73.0% to 84.4%) in the neoadjuvant chemotherapy group and 72.3% (95% CI 65.8% to 77.8%) in the standard-of-care group (RMST difference 6.1 months, 95% CI 0.93-11.37 months, P= 0.021). The 7-year OS was 81.9% (95% CI 75.8% to 86.6%) in the neoadjuvant chemotherapy group and 76.1% (95% CI 69.7% to 81.2%) in the standard-of-care group (RMST difference 4.37 months, 95% CI 0.35-8.38 months, P= 0.033). The safety profile remained unchanged since the previous analysis. Neoadjuvant chemotherapy with mFOLFIRINOX followed by chemoradiotherapy improved OS, confirmed long-term DFS and MFS benefits in LARC patients, and should be considered as one of the best options of care for these patients.

An Institutional Shift from Routine to Selective Diversion of Low Anastomosis in Robotic TME Surgery for Rectal Cancer Patients Using the KHANS Technique: A Single-Centre Cohort Study.

(1) Background: In recent years, there has been a change in practice for diverting stomas in rectal cancer surgery, shifting from routine diverting stomas to a more selective approach. Studies suggest that the benefits of temporary ileostomies do not live up to their risks, such as high-output stomas, stoma dysfunction, and reoperation. (2) Methods: All rectal cancer patients treated with a robotic resection in a single tertiary colorectal centre in the UK from 2013 to 2021 were analysed. In 2015, our unit made a shift to a more selective approach to temporary diverting ileostomies. The cohort was divided into a routine diversion group treated before 2015 and a selective diversion group treated after 2015. Both groups were analysed and compared for short-term outcomes and morbidities. (3) Results: In group A, 63/70 patients (90%) had a diverting stoma compared to 98/135 patients (72.6%) in group B (p = 0.004). There were no significant differences between the groups in anastomotic leakages (11.8% vs. 17.8%, p = 0.312) or other complications (p = 0.117). There were also no significant differences in readmission (3.8% vs. 2.6%, p = 0.312) or reoperation (3.8% vs. 2.6%, p = 1.000) after stoma closure. After 1 year, 71.6% and 71.9% (p = 1.000) of patients were stoma-free. One major reason for the delay in stoma reversal was the COVID-19 pandemic, which only occurred in group B (0% vs. 22%, p = 0.054). (4) Conclusions: A more selective approach to diverting stomas for robotic rectal cancer patients does not lead to more complications or leaks and can be considered in the treatment of rectal cancer tumours.

439 Predictors of Treatment Pathway Completion in Stage IV Rectal Cancer: A Nationwide Observational Study of 15,727 Patients

Abstract Aim Stage IV rectal cancer carries a 10% 5-year survival rate. Curative-intent management requires treatment of both the primary and metastatic disease. This study aimed to identify patterns in stage IV rectal cancer treatment pathway at population level across the UK, and to identify predictors of treatment pathway completion. Method Patient demographics and treatment data were extracted from the UK Colorectal Cancer Intelligence Hub’s CORECT-R repository, national chemotherapy (SACT), and radiotherapy (RTDS) datasets. Treatment pathway completion was defined as receipt of intervention to the primary tumour (radiotherapy and/or surgery) in addition to metastasis-directed therapy (surgery, radiotherapy, OR ablation), or the combination alongside chemotherapy. Multivariable logistic regression analysis was performed to identify independent predictors of treatment completion. Results A total of 15,727 patients with stage IV rectal cancer diagnosed between 2010-19 were identified. Multivariable analyses showed that sex, age, number of cancer alliances (CAs) attended, ethnicity, and deprivation score were all statistically significant in predicting completion of treatment (p-values<0.02). The number of CAs attended was identified as having the strongest predictive effect of treatment completion (OR=3.9, CI: 3.5–4.3). Being male also increased the odds of completing treatment (OR=1.2, CI: 1.1-1.3), while increased deprivation reduced odds of completing treatment. Conclusions Across the UK, there is variation in Stage IV rectal cancer patients completing treatment for both their primary and metastatic disease. Further work is needed to determine whether differences in treatment pathways stem from variation in access to specialist services between alliances or whether they are due to differences in MDT decision making.

247 Prophylactic Use of 3D Intraperitoneal Mesh in the Prevention of Parastomal Hernia in Permanent Colostomies After Rectal Cancer Resection

Abstract Background Parastomal hernia (PSH) is the most common complication of stomas associated with significant morbidity. Prophylactic mesh in preventing PSH is less well studied, and evidence is conflicting. We compare PSH rates in patients in whom 3D intraperitoneal mesh was and was not used prophylactically in a cohort of rectal cancer patients undergoing elective curative resection. Method Retrospective data from the Somerset Database and Electronic Patient Record were collected on patients under a single consultant surgeon between May 2016 and December 2021. Follow up was for a minimum of 2 years (excluding deaths). Appropriate statistical tests of difference significance were performed for proportions of categorical data, and time to hernia occurrence in patients with and without Dynamesh IPST placement. (Fisher’s Exact test; Kaplan Meier) Results From 397 colorectal cancer patients under the care of a single surgeon, 223 had elective surgery with curative intent, of which 63 (28%) underwent total mesorectal excision (TME) (30 TME & ileostomy, 12 TME Hartmann and 21 APER) - 90% laparoscopic. 16 patients had prophylactic mesh used. Demographics and co-morbidities between groups were similar. PSH incidence was 1 (6%) (radiological) vs.7 (41%) (clinical) in the mesh vs. non-mesh group; P=0.039. Post operative complications and pain scores differed only slightly. Time to hernia development did not differ between groups. Conclusions Use of prophylactic mesh during permanent stoma formation in our practice appears safe, and effective in preventing PSH. Further studies may answer the question “Should 3D collared mesh be routinely placed during the formation of permanent stomas to prevent parastomal hernia?”

327 Impact of Adjuvant Chemotherapy/Radiotherapy on the 5 Year Overall Survival of Patients with Non-Metastatic Rectal Cancer in Bulgaria - a Retrospective Population-Wide Observational Study

Abstract Introduction Survival rates of patients with non-metastatic rectal cancer (RC) have increased, due the use of adjuvant chemotherapy/radiotherapy post-surgery, recommended by the National Comprehensive Cancer Network (NCCN) [1–3]. The aim of the study was to analyse the impact of adjuvant chemotherapy/radiotherapy on the 5-year overall survival (OS) of patients diagnosed with non-metastatic RC patients in Bulgaria. Method This is a retrospective population wide observational study of 8968 cases registered with Colorectal cancer in the Bulgarian National Cancer Registry (BNCR) between 2015 and 2016. The mean and median age of patients with left colon (LCC) and right colon (RCC) along with rectal cancer (RC) was analysed. The impact of adjuvant chemotherapy and radiotherapy on the 5-Year OS for non-metastatic RC was analysed. Kaplan-Meier curve with log rank, ANOVA and chi-squared tests were used to estimate the statistical significance. Results The mean age at diagnosis for RCC, LCC and RC was 68.9, 67.41 and 66.4 respectively (p-Value=<0.001). The median age at diagnosis was 69, 68 and 67 for RCC, LCC and RC respectively. Our study showed that patients with non-metastatic RC that received both adjuvant chemotherapy and radiotherapy had a higher 5-year OS compared to patients who received either chemotherapy, radiotherapy or neither therapy (61.4%, 59.5%, 56.2%, 51.8%), p-Value=0.007. Less than 40% of patients received either adjuvant chemotherapy or radiotherapy. Conclusions Adjuvant chemotherapy/radiotherapy improves the 5-Year OS for patients with non-metastatic RC. NCCN guidelines should be implemented in Bulgaria [1–3]. Bulgaria will benefit by implementing an organised screening programme [4].

Gustative Roussy Immune Score is a Predictor for Major Pathological Response in Rectal Cancer: A Result from the Preoperative Intraarterial Chemoembolization Combined with Radiotherapy (PCAR) Study

Despite the emergence of various treatment strategies for rectal cancer based on neoadjuvant chemoradiotherapy, there is currently a lack of reliable biomarkers to determine which patients will respond well to neoadjuvant chemoradiotherapy. Through collecting hematological and biochemical parameters data of patients prior to receiving neoadjuvant chemoradiotherapy, we evaluated the predictive value of systemic inflammatory indices for pathological response and prognosis in rectal cancer patients. We found that baseline GRIm-Score was an independent predictor for MPR in rectal cancer patients. However, no association was observed between several commonly systemic inflammation indices and long-term outcome.

Localized fine-tuning and clinical evaluation of deep-learning based auto-segmentation (DLAS) model for clinical target volume (CTV) and organs-at-risk (OAR) in rectal cancer radiotherapy

Background and purposeVarious deep learning auto-segmentation (DLAS) models have been proposed, some of which have been commercialized. However, the issue of performance degradation is notable when pretrained models are deployed in the clinic. This study aims to enhance precision of a popular commercial DLAS product in rectal cancer radiotherapy by localized fine-tuning, addressing challenges in practicality and generalizability in real-world clinical settings.Materials and methodsA total of 120 Stage II/III mid-low rectal cancer patients were retrospectively enrolled and divided into three datasets: training (n = 60), external validation (ExVal, n = 30), and generalizability evaluation (GenEva, n = 30) datasets respectively. The patients in the training and ExVal dataset were acquired on the same CT simulator, while those in GenEva were on a different CT simulator. The commercial DLAS software was first localized fine-tuned (LFT) for clinical target volume (CTV) and organs-at-risk (OAR) using the training data, and then validated on ExVal and GenEva respectively. Performance evaluation involved comparing the LFT model with the vendor-provided pretrained model (VPM) against ground truth contours, using metrics like Dice similarity coefficient (DSC), 95th Hausdorff distance (95HD), sensitivity and specificity.ResultsLFT significantly improved CTV delineation accuracy (p < 0.05) with LFT outperforming VPM in target volume, DSC, 95HD and specificity. Both models exhibited adequate accuracy for bladder and femoral heads, and LFT demonstrated significant enhancement in segmenting the more complex small intestine. We did not identify performance degradation when LFT and VPM models were applied in the GenEva dataset.ConclusionsThe necessity and potential benefits of LFT DLAS towards institution-specific model adaption is underscored. The commercial DLAS software exhibits superior accuracy once localized fine-tuned, and is highly robust to imaging equipment changes.

Effect of Multimodal Prehabilitation on Muscle Mass in Rectal Cancer Patients Receiving Neoadjuvant Treatment

Effect of Multimodal Prehabilitation on Muscle Mass in Rectal Cancer Patients Receiving Neoadjuvant Treatment

Implications of pretreatment extramural venous invasion in rectal cancer patients: A population-based study.

Extramural venous invasion detected by MRI (mrEMVI) has in several expert centre studies been identified as an important prognostic factor in rectal cancer, and in guiding neoadjuvant therapy. However, population-based evidence for mrEMVI as a predictor for recurrent disease is lacking. This was a multicentre retrospective study based on the Swedish Colorectal Cancer Registry. The study period encompassed patients operated with abdominal resection for rectal cancer 2017-2021, with follow-up until January 2023. Patients diagnosed at hospitals with radiological registry data coverage <90% or with metastatic disease were excluded. Pretreatment mrEMVI constituted exposure, while recurrence-free survival was the main outcome. Distant and local recurrence, and overall survival were secondary outcomes, and pretreatment and postoperative scenarios were explored using multivariable Cox regression with multiple imputation. Hazard ratios (HRs) with 95% confidence intervals (CIs) were reported. A total of 2737 patients from 13 hospitals were eligible for analysis. Pretreatment mrEMVI was reported in 14.5% of patients, while 71.9% had negative findings and 13.6% had missing data. In the pretreatment scenario, mrEMVI was an independent predictor for worse recurrence-free survival with an adjusted HR of 1.64 (95% CI: 1.31-2.06). In the postoperative MDT setting, the influence of mrEMVI on recurrence-free survival decreased with an adjusted HR of 1.27 (95% CI: 1.00-1.61). mrEMVI at diagnosis is an independent predictor of recurrence-free survival in an unselected population of rectal cancer patients undergoing abdominal resection.

Nonoperative management and local excision after neoadjuvant chemoradiation therapy for rectal cancer.

Locally advanced extraperitoneal rectal cancer represents a significant clinical challenge, and currently, the standard treatment is based on neoadjuvant chemoradiation therapy (CRT) followed by radical surgical resection with total mesorectal excision (TME). In the last 30 years, its management has undergone significant changes due to the improvement of complementary radio- and chemotherapy treatments, the improvement of minimally invasive surgical approaches and the diffusion of organ-sparing approaches, such as nonoperative management, commonly called "watch and wait" (NOM) and local excision (LE), in highly selected patients who achieve a major or complete response to neoadjuvant CRT. This review aimed to critically examine the efficacy and oncological safety of NOM and LE compared to those of standard TME in rectal cancer patients after neoadjuvant CRT. Both the pros and cons of these approaches were strictly analyzed, providing a comprehensive and critical overview of these novel management strategies for rectal cancer.

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

BackgroundTransanal 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. ObjectiveTo report incidence of postoperative urinary retention and evaluate the associated risk factors for transanal total mesorectal excision. DesignIn 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. PatientsWe enrolled 524 patients who underwent total mesorectal excision for stage I–III rectal cancer between June 2019 and April 2022. Main outcome measuresThe incidence of postoperative urinary retention. ResultsAmong 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). LimitationsThe generalizability of the findings outside specialist rectal cancer centers may be limited. ConclusionsTransanal 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.