Feasibility and safety of minimally invasive multivisceral resection for T4b rectal cancer: A 9-year review.

BACKGROUND: Colorectal cancer is the third most common cancer and the second highest cause of cancer-related mortality worldwide. About 5%-10% of patients are diagnosed with locally advanced rectal cancer (LARC) on presentation. For LARC invading into other structures (i.e. T4b), multivisceral resection (MVR) and/or pelvic exenteration (PE) remains the only potential curative surgical treatment. MVR and/or PE is a major and complex surgery with high post-operative morbidity. Minimally invasive surgery (MIS) has been shown to improve short-term post-operative outcomes in other gastrointestinal malignancies, but there is little evidence on its use in MVR, especially so for robotic MVR. AIM: To assess the feasibility and safety of minimally invasive MVR (miMVR), and compare post-operative outcomes between robotic and laparoscopic MVR. METHODS: This is a single-center retrospective cohort study from 1st January 2015 to 31st March 2023. Inclusion criteria were patients diagnosed with cT4b rectal cancer and underwent MVR, or stage 4 disease with resectable systemic metastases. Patients who underwent curative MVR for locally recurrent rectal cancer, or metachronous rectal cancer were also included. Exclusion criteria were patients with systemic metastases with non-resectable disease. All patients planned for elective surgery were enrolled into the standard enhanced recovery after surgery pathway with standard peri-operative management for colorectal surgery. Complex surgery was defined based on technical difficulty of surgery (i.e. total PE, bladder-sparing prostatectomy, pelvic lymph node dissection or need for flap creation). Our primary outcomes were the margin status, and complication rates. Categorical values were described as percentages and analysed by the chi-square test. Continuous variables were expressed as median (range) and analysed by Mann-Whitney U test. Cumulative overall survival (OS) and recurrence-free survival (RFS) were analysed using Kaplan-Meier estimates with life table analysis. Log-rank test was performed to determine statistical significance between cumulative estimates. Statistical significance was defined as P < 0.05. RESULTS: A total of 46 patients were included in this study [open MVR (oMVR): 12 (26.1%), miMVR: 36 (73.9%)]. Patients' American Society of Anesthesiologists score, body mass index and co-morbidities were comparable between oMVR and miMVR. There is an increasing trend towards robotic MVR from 2015 to 2023. MiMVR was associated with lower estimated blood loss (EBL) (median 450 vs 1200 mL, P = 0.008), major morbidity (14.7% vs 50.0%, P = 0.014), post-operative intra-abdominal collections (11.8% vs 50.0%, P = 0.006), post-operative ileus (32.4% vs 66.7%, P = 0.04) and surgical site infection (11.8% vs 50.0%, P = 0.006) compared with oMVR. Length of stay was also shorter for miMVR compared with oMVR (median 10 vs 30 d, P = 0.001). Oncological outcomes-R0 resection, recurrence, OS and RFS were comparable between miMVR and oMVR. There was no 30-d mortality. More patients underwent robotic compared with laparoscopic MVR for complex cases (robotic 57.1% vs laparoscopic 7.7%, P = 0.004). The operating time was longer for robotic compared with laparoscopic MVR [robotic: 602 (400-900) min, laparoscopic: Median 455 (275-675) min, P < 0.001]. Incidence of R0 resection was similar (laparoscopic: 84.6% vs robotic: 76.2%, P = 0.555). Overall complication rates, major morbidity rates and 30-d readmission rates were similar between laparoscopic and robotic MVR. Interestingly, 3-year OS (robotic 83.1% vs 58.6%, P = 0.008) and RFS (robotic 72.9% vs 34.3%, P = 0.002) was superior for robotic compared with laparoscopic MVR. CONCLUSION: MiMVR had lower post-operative complications compared to oMVR. Robotic MVR was also safe, with acceptable post-operative complication rates. Prospective studies should be conducted to compare short-term and long-term outcomes between robotic vs laparoscopic MVR.

Early rectal cancer: The diagnostic performance of MRI supplemented with a rectal micro-enema and a modified staging system to identify tumors eligible for local excision.

Background: In staging early rectal cancers (ERC), submucosal tumor depth is one of the most important features determining the possibility of local excision (LE). The micro-enema (Bisacodyl) induces submucosal edema and may hypothetically improve the visualization of tumor depth. Purpose: To test the diagnostic performance of MRI to identify ERC suitable for LE when adding a pre-procedural micro-enema and concurrent use of a modified classification system. Material and Methods: In this prospective study, we consecutively included 73 patients with newly diagnosed rectal tumors. Two experienced radiologists independently interpreted the MRI examinations, and diagnostic performance was calculated for local tumors eligible for LE (Tis-T1sm2, n = 43) and non-local tumors too advanced for LE (T1sm3-T3b, n = 30). Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were registered for each reader. Inter- and intra-reader agreements were assessed by kappa statistics. Lymph node status was derived from the clinical MRI reports. Results: Reader1/reader2 achieved sensitivities of 93%/86%, specificities of 90%/83%, PPV of 93%/88%, and NPV of 90%/81%, respectively, for identifying tumors eligible for LE. Rates of overstaging of local tumors were 7% and 14% for the two readers, and kappa values for the inter- and intra-reader agreement were 0.69 and 0.80, respectively. For tumors ≤T2, all metastatic lymph nodes were smaller than 3 mm on histopathology. Conclusion: MRI after a rectal micro-enema and concurrent use of a modified staging system achieved good diagnostic performance to identify tumors suitable for LE. The rate of overstaging of local tumors was comparable to results reported in previous endorectal ultrasound (ERUS) studies.

Does Tri-Staple™ technology reduce the risk of anastomotic leakage in colorectal surgery? A propensity score matching analysis.

BACKGROUND AND OBJECTIVES: This study evaluates the Tri-Staple™ technology in colorectal anastomosis. METHODS: Patients who underwent rectosigmoidectomy between 2016 and 2022 were retrospectively evaluated and divided into two groups: EEA™ (EEA) or Tri-Staple™ (Tri-EEA). The groups were matched for age, sex, American Society of Anesthesiologists (ASA), and neoadjuvant radiotherapy using propensity score matching (PSM). RESULT: Three hundred and thirty-six patients were included (228 EEA; 108 Tri-EEA). The groups were similar in sex, age, and neoadjuvant therapy. The Tri-EEA group had fewer patients with ASA III/IV scores (7% vs. 33%; p < 0.001). The Tri-EEA group had a lower incidence of leakage (4% vs. 11%; p = 0.023), reoperations (4% vs. 12%; p = 0.016), and severe complications (6% vs. 14%; p = 0.026). There was no difference in complications, mortality, readmission, and length of stay. After PSM, 108 patients in the EEA group were compared with 108 in the Tri-EEA group. The covariates sex, age, neoadjuvant radiotherapy, and ASA were balanced, and the risk of leakage (4% vs. 12%; p = 0.04), reoperation (4% vs. 14%; p = 0.014), and severe complications (6% vs. 15%; p = 0.041) remained lower in the Tri-EEA group. CONCLUSION: Tri-Staple™ reduces the risk of leakage in colorectal anastomosis. However, this study provides only insights, and further research is warranted to confirm these findings.

Adjuvant therapy for rare rectal gastrointestinal stromal tumors: A case report.

Key Clinical Message: Anorectal gastrointestinal stromal tumors are extremely rare, constituting less than 0.1% of rectal tumors. Surgical resection using a transanal wide excision followed by adjuvant therapy with tyrosine kinase inhibitors can be a successful treatment combination to remove the mass and prevent recurrence while preserving the integrity of the anal sphincter. Abstract: Gastrointestinal stromal tumors (GISTs) are a rare subset of neoplasms, accounting for about 1%-2% of primary gastrointestinal malignancies. The stomach is the most common site for GISTs, with anorectal GISTs being exceptionally rare, representing only 0.1% of all rectal tumors. The standard approach for managing localized GIST involves complete surgical excision to achieve negative microscopic margins (R0) while preserving the tumor capsule and maintaining anal sphincter function. Surgical resection with transanal wide excision followed by adjuvant therapy using tyrosine kinase inhibitors can successfully remove the mass, prevent recurrence, and preserve the anal sphincter's integrity. Adjuvant therapy with imatinib is the recommended treatment for all localized GISTs assessed to have an intermediate or high risk of relapse. Here, we report a case of a 63-year-old male with a rectal GIST who underwent transanal wide excision followed by adjuvant therapy with tyrosine kinase inhibitors.

Analysis of Bacterial Culture of Fluid in the Surgical Area in Transanal Total Mesorectal Excision and Laparoscopic Total Mesorectal Excision.

Purpose: To investigate the clinical value of the bacterial culture of fluid in the surgical area in laparoscopic transanal total mesorectal excision (Lap-taTME) and laparoscopic total mesorectal excision (Lap-TME). Methods: Clinical data of 106 patients with rectal cancer who had undergone surgery were retrospectively collected, including 56 patients in the Lap-taTME group and 50 patients in the Lap-TME group. In the Lap-taTME group, the initial pelvic fluid, the rectal cavity fluid after purse-string suture, and the pelvic cavity fluid after anastomosis were collected and recorded as culture No. 1, No. 2, and No. 3, respectively. In the Lap-TME group, culture No. 1 and No. 3 were collected as done in the Lap-taTME group. The culture results and postoperative complications were statistically analyzed. Results: The positive rate of culture No. 1 was zero in both groups, and there were 6 cases (10.7%) with positive culture No. 2 in the Lap-taTME group. However, the number of patients with positive culture No. 3 (7, 12.5%) and cumulative positive culture cases (11, 19.6%) in the Lap-taTME group were significantly higher than those in the Lap-TME group (0) (all P < .05). Pelvic infection occurred in 4 (7.1%) of the 11 cases (19.6%) with positive culture in the Lap-taTME group, accounting for 36.4% (4/11). There were no significant intergroup differences in anastomotic leakage and pelvic infection (all P > .05). Conclusion: Positive bacterial culture of fluid during Lap-taTME indicates an increased risk of pelvic infection after operation. Lap-taTME is more prone to intraoperative contamination than Lap-TME but does not significantly increase the risk of postoperative pelvic infection.

Sex Disparities in Rectal Cancer Surgery: An In-Depth Analysis of Surgical Approaches and Outcomes.

Anatomical and physiological differences exist between sex, leading to variations in how diseases, such as rectal cancer, are prevalence and treatment outcomes of diseases including rectal cancer. In particular, in the case of rectal cancer, anatomical differences may be associated with surgical challenges, and these factors are believed to be important contributors to potential disparities in postoperative recovery, associated complications, and oncological outcomes between male and female patients. However, there is still ongoing debate regarding this matter. Significantly, the male pelvic anatomy is distinguished by its narrower dimensions, which can present surgical challenges and impede visual access during operative procedures, rendering it more complex than surgical interventions in the female pelvis. As a result, this anatomical difference leads to a greater occurrence of postoperative complications, such as anastomotic leakage. Moreover, the pelvis houses nerves that are vital for urinary and genital functions, underscoring the need to assess the potential risks of sexual and urinary dysfunction in rectal cancer surgery. These postoperative complications can significantly impact the quality of life; therefore, it is imperative to perform surgery with an understanding of the structural differences between sexes. Therefore, to address the limitations imposed by anatomical structures, new approaches such as robotic surgery, trans-anal total mesorectal excision, and intraoperative neuromonitoring are being introduced. Furthermore, it is essential to conduct research into fundamental mechanisms that may give rise to differences in surgical outcomes and oncological results between sexes. By comprehending the disparities between males and females, we can advance toward personalized treatments. Consequently, this review outlines variations in surgical approaches, complications, and treatments for rectal cancer in male and female patients.

Interpretation of Complete Tumor Response on MRI Following Chemoradiotherapy of Rectal Cancer: Inter-Reader Agreement and Associated Factors in Multi-Center Clinical Practice.

OBJECTIVE: To measure inter-reader agreement and identify associated factors in interpreting complete response (CR) on magnetic resonance imaging (MRI) following chemoradiotherapy (CRT) for rectal cancer. MATERIALS AND METHODS: This retrospective study involved 10 readers from seven hospitals with experience of 80-10210 cases, and 149 patients who underwent surgery after CRT for rectal cancer. Using MRI-based tumor regression grading (mrTRG) and methods employed in daily practice, the readers independently assessed mrTRG, CR on T2-weighted images (T2WI) denoted as mrCRT2W, and CR on all images including diffusion-weighted images (DWI) denoted as mrCRoverall. The readers described their interpretation patterns and how they utilized DWI. Inter-reader agreement was measured using multi-rater kappa, and associated factors were analyzed using multivariable regression. Correlation between sensitivity and specificity of each reader was analyzed using Spearman coefficient. RESULTS: The mrCRT2W and mrCRoverall rates varied widely among the readers, ranging 18.8%-40.3% and 18.1%-34.9%, respectively. Nine readers used DWI as a supplement sequence, which modified interpretations on T2WI in 2.7% of cases (36/1341 [149 patients × 9 readers]) and mostly (33/36) changed mrCRT2W to non-mrCRoverall. The kappa values for mrTRG, mrCRT2W, and mrCRoverall were 0.56 (95% confidence interval: 0.49, 0.62), 0.55 (0.52, 0.57), and 0.54 (0.51, 0.57), respectively. No use of rectal gel, larger initial tumor size, and higher initial cT stage exhibited significant association with a higher inter-reader agreement for assessing mrCRoverall (P ≤ 0.042). Strong negative correlations were observed between the sensitivity and specificity of individual readers (coefficient, -0.718 to -0.963; P ≤ 0.019). CONCLUSION: Inter-reader agreement was moderate for assessing CR on post-CRT MRI. Readers' varying standards on MRI interpretation (i.e., threshold effect), along with the use of rectal gel, initial tumor size, and initial cT stage, were significant factors associated with inter-reader agreement.

Image-based artificial intelligence for the prediction of pathological complete response to neoadjuvant chemoradiotherapy in patients with rectal cancer: a systematic review and meta-analysis.

OBJECTIVE: Artificial intelligence (AI) holds enormous potential for noninvasively identifying patients with rectal cancer who could achieve pathological complete response (pCR) following neoadjuvant chemoradiotherapy (nCRT). We aimed to conduct a meta-analysis to summarize the diagnostic performance of image-based AI models for predicting pCR to nCRT in patients with rectal cancer. METHODS: This study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A literature search of PubMed, Embase, Cochrane Library, and Web of Science was performed from inception to July 29, 2023. Studies that developed or utilized AI models for predicting pCR to nCRT in rectal cancer from medical images were included. The Quality Assessment of Diagnostic Accuracy Studies-AI was used to appraise the methodological quality of the studies. The bivariate random-effects model was used to summarize the individual sensitivities, specificities, and areas-under-the-curve (AUCs). Subgroup and meta-regression analyses were conducted to identify potential sources of heterogeneity. Protocol for this study was registered with PROSPERO (CRD42022382374). RESULTS: Thirty-four studies (9933 patients) were identified. Pooled estimates of sensitivity, specificity, and AUC of AI models for pCR prediction were 82% (95% CI: 76-87%), 84% (95% CI: 79-88%), and 90% (95% CI: 87-92%), respectively. Higher specificity was seen for the Asian population, low risk of bias, and deep-learning, compared with the non-Asian population, high risk of bias, and radiomics (all P < 0.05). Single-center had a higher sensitivity than multi-center (P = 0.001). The retrospective design had lower sensitivity (P = 0.012) but higher specificity (P < 0.001) than the prospective design. MRI showed higher sensitivity (P = 0.001) but lower specificity (P = 0.044) than non-MRI. The sensitivity and specificity of internal validation were higher than those of external validation (both P = 0.005). CONCLUSIONS: Image-based AI models exhibited favorable performance for predicting pCR to nCRT in rectal cancer. However, further clinical trials are warranted to verify the findings.

Fournier's gangrene due to rectal cancer: A case report.

Fournier's gangrene (FG) is an extremely rare necrotizing fasciitis that is insidious, rapidly spreading and life-threatening. FGs due to rectal cancer occur rarely and there is a lack of clinical reference. In the present study, a severe FG due to rectal cancer perforation was described and the features of this rare disease were summarized with a literature review. A 57-year-old man was admitted because of rectal cancer-induced FG. The patient was misdiagnosed with extensive perianal abscess until the intraoperative biopsy confirmed that rectal cancer was the culprit. Incision, debridement and drainage were carried out to reduce infectious burdens. After that, the patient was transferred to Peking University People's Hospital for the subsequent therapy. Empirical broad-spectrum antibiotic therapy was used at the initial stage. Diversional transverse loop colostomy was performed to control infection and resume oral feeding. After four rounds of vacuum-assisted closure (VAC) therapy, radical resection and wound closure were accomplished. The scrotal defect was repaired by a skin flap. Pathological results indicated a moderately differentiated adenocarcinoma with perforation. The patient was discharged from the hospital on postoperative day 15 without any post-operative complications. No signs of recurrence were observed during a 22-month follow-up. In the setting of rectal cancer-induced FGs, the liquid resuscitation, broad-spectrum antibiotic therapy, and prompt debridement are the cornerstones of the initial management. Diversional colostomy and VAC therapy were effective in the management of severe infection and large wounds. The present case report also provided a clinical reference for the implementation of staged surgeries and the perioperative multidisciplinary management of FGs.

Low energy contact X-ray brachytherapy for treatment of rectal cancer: a health technology appraisal by Health Technology Wales.

AIM: Health Technology Wales sought to evaluate the clinical and cost-effectiveness of contact X-ray brachytherapy (CXB) for early-stage rectal cancer. METHODS: Relevant studies were identified through systematic searches of MEDLINE, Embase, Cochrane Library and Scopus. A cost-utility model was developed to estimate the cost-effectiveness of CXB in National Health Service Wales, using results of the Organ Preservation in Early Rectal Adenocarcinoma (OPERA) trial. Patient perspectives were obtained through the Papillon Patient Support group and All-Wales Cancer Network. RESULTS: The OPERA randomized controlled trial showed that CXB improved complete response and organ preservation rates compared with external-beam boost for people with T2-3b, N0-1, M0 rectal cancer who are fit for surgery. Managing more of this population non-operatively after CXB was estimated to provide 0.2 quality-adjusted life years at an additional cost of £887 per person. CXB was cost effective compared with external-beam boost at a cost of £4463 per quality-adjusted life year gained. This conclusion did not change in scenario analysis and CXB was cost effective in 91% of probabilistic sensitivity analyses. Patients valued receiving clear information on all available options to support their individual treatment choices. The detrimental impact of a stoma on quality of life led some patients to reject the idea that surgery was their only option. CONCLUSION: This evidence review and cost-utility analysis indicates that CXB is likely to be clinically and cost effective, as part of a watch and wait strategy for adults fit for surgery. Wider access to CXB is supported by patient testimonies.

Comparison of hand-sewn anterior repair, resection and hand-sewn anastomosis, resection and stapled anastomosis techniques for the reversal of diverting loop ileostomy after low anterior rectal resection: a randomized clinical trial.

BACKGROUND: Low anterior resection in patients with rectal cancer may require a defunctioning loop ileostomy formation that requires closure after a period of time. There are three common techniques for ileostomy closure: anterior repair (AR or fold-over closure), resection and hand-sewn anastomosis (RHA), and resection and stapled anastomosis (RSA). We aimed to compare them on the basis of operative and postoperative features. METHODS: Patients with rectal cancer who underwent low anterior resection without complications were included in this study and randomly assigned to three parallel groups to undergo loop ileostomy closure via either AR, RHA, or RSA. Early and late outcomes were gathered from all included patients. RESULTS: Among 93 patients with a mean age of 56.21 ± 11.78 years, consisting of 58 (62.4%) men, 31 patients underwent AR, 30 patients RHA, and 32 patients RSA. There was no significant difference among the groups regarding the frequency and location of intraoperative injuries (P = 0.157). The AR groups demonstrated significantly less consumption of gauzes following intraoperative bleeding compared to the two others groups. The results showed that the duration of surgery in the RSA was significantly shorter than in the AR or RHA group (both P < 0.001). Regarding postoperative course, only one case of hematoma and two cases of surgical wound infection occurred in the RHA group. Anastomotic leakage and complete or partial obstruction did not occur in any group of patients. Latent postoperative complications did not occur in any group of patients. The median time between surgery and discharge as well as the interval until first gas passage, first defecation, oral tolerated liquid diet, as well as oral tolerated soft and regular diet in the AR group were significantly lower than in the two other groups (both P < 0.001). However, there was no statistical difference in these intervals between the RHA and RSA groups. CONCLUSIONS: Resection and stapled anastomosis had the shortest duration among the three techniques; however, anterior repair had faster recovery, including earlier tolerated oral diet, gas passing and defecation, and discharge, in comparison with the other techniques. TRIAL REGISTRATION: Trial registration number IRCT20120129008861N5.

Bowel dysfunction and lower urinary tract symptoms on quality of life after sphincter-preserving surgery for rectal cancer: A cross-sectional study.

OBJECTIVES: This study aimed to investigate the impact of bowel dysfunction and lower urinary tract symptoms on the quality of patients with rectal cancer who underwent sphincter-preserving surgery. METHODS: This cross-sectional study included patients who were followed up after sphincter-preserving surgery in Korea. Data were collected from May 2022 to February 2023. The participants (n = 110) responded to self-reported questionnaires assessing the Low Anterior Resection Syndrome (LARS) score, International Prostate Symptom Score (IPSS), European Organization for Research and Treatment of Cancer QLQ-C30 and QLQ-C29 questionnaires. RESULTS: Among the participants, 66.4% had major low anterior resection syndrome, and 39.1% had moderate-to-severe lower urinary tract symptoms. Patients with higher severity of low anterior resection syndrome and lower urinary tract symptoms had a lower quality of life. The IPSS, performance status, duration since the end of the surgery, comorbidities, LARS scores, and tumor location on the anal verge negatively affected the quality of life. CONCLUSION: Patients with more severe bowel dysfunction or lower urinary tract symptoms have a poorer quality of life. Nurses should be made aware of the factors that can reduce the quality of life of patients who have undergone sphincter-preserving surgery. Accordingly, they should plan to address the various nursing problems.

T2WI-based MRI radiomics for the prediction of preoperative extranodal extension and prognosis in resectable rectal cancer.

OBJECTIVE: To investigate whether T2-weighted imaging (T2WI)-based intratumoral and peritumoral radiomics can predict extranodal extension (ENE) and prognosis in patients with resectable rectal cancer. METHODS: One hundred sixty-seven patients with resectable rectal cancer including T3T4N + cases were prospectively included. Radiomics features were extracted from intratumoral, peritumoral 3 mm, and peritumoral-mesorectal fat on T2WI images. Least absolute shrinkage and selection operator regression were used for feature selection. A radiomics signature score (Radscore) was built with logistic regression analysis. The area under the receiver operating characteristic curve (AUC) was used to evaluate the performance of each Radscore. A clinical-radiomics nomogram was constructed by the most predictive radiomics signature and clinical risk factors. A prognostic model was constructed by Cox regression analysis to identify 3-year recurrence-free survival (RFS). RESULTS: Age, cT stage, and lymph node-irregular border and/or adjacent fat invasion were identified as independent clinical risk factors to construct a clinical model. The nomogram incorporating intratumoral and peritumoral 3 mm Radscore and independent clinical risk factors achieved a better AUC than the clinical model in the training (0.799 vs. 0.736) and validation cohorts (0.723 vs. 0.667). Nomogram-based ENE (hazard ratio [HR] = 2.625, 95% CI = 1.233-5.586, p = 0.012) and extramural vascular invasion (EMVI) (HR = 2.523, 95% CI = 1.247-5.106, p = 0.010) were independent risk factors for predicting 3-year RFS. The prognostic model constructed by these two indicators showed good performance for predicting 3-year RFS in the training (AUC = 0.761) and validation cohorts (AUC = 0.710). CONCLUSION: The nomogram incorporating intratumoral and peritumoral 3 mm Radscore and clinical risk factors could predict preoperative ENE. Combining nomogram-based ENE and MRI-reported EMVI may be useful in predicting 3-year RFS. CRITICAL RELEVANCE STATEMENT: A clinical-radiomics nomogram could help preoperative predict ENE, and a prognostic model constructed by the nomogram-based ENE and MRI-reported EMVI could predict 3-year RFS in patients with resectable rectal cancer. KEY POINTS: • Intratumoral and peritumoral 3 mm Radscore showed the most capability for predicting ENE. • Clinical-radiomics nomogram achieved the best predictive performance for predicting ENE. • Combining clinical-radiomics based-ENE and EMVI showed good performance for 3-year RFS.

Long-term bowel functional outcomes following anal sphincter-preserving surgery for upper and middle rectal cancer: a single-center longitudinal study.

PURPOSE: Despite advances in neoadjuvant chemoradiotherapy and anal sphincter-preserving surgery for rectal cancer, bowel dysfunction is still unavoidable and negatively affects patients' quality of life. In this longitudinal study, we aimed to investigate the changes in bowel function with follow-up time and the effect of neoadjuvant chemoradiotherapy on bowel function following low anterior resection for rectal cancer. METHODS: In this study, 171 patients with upper or middle rectal cancer who underwent low anterior resection between 2012 and 2018 were included. Bowel function was assessed longitudinally with Memorial Sloan Kettering Cancer Center Bowel Function Instrument and Wexner scores every 6 months after restoration of bowel continuity. Patients with at least 2 follow-up visits were included. RESULTS: Overall, 100 patients received neoadjuvant chemoradiotherapy. Urgency, soilage, and fecal incontinence were noted within 24 months in the patients treated with neoadjuvant chemoradiotherapy. After 2 years of follow-up, significant bowel dysfunction and fecal incontinence were observed in the neoadjuvant chemoradiotherapy group. Low tumor level and neoadjuvant chemoradiotherapy were associated with delayed bowel dysfunction. CONCLUSION: Neoadjuvant chemoradiotherapy in combination with low tumor level was significantly associated with delayed bowel dysfunction even after 2 years of follow-up. Therefore, careful selection and discussion with patients are paramount.

Performance reporting design in artificial intelligence studies using image-based TNM staging and prognostic parameters in rectal cancer: a systematic review.

PURPOSE: The integration of artificial intelligence (AI) and magnetic resonance imaging in rectal cancer has the potential to enhance diagnostic accuracy by identifying subtle patterns and aiding tumor delineation and lymph node assessment. According to our systematic review focusing on convolutional neural networks, AI-driven tumor staging and the prediction of treatment response facilitate tailored treat-ment strategies for patients with rectal cancer. METHODS: This paper summarizes the current landscape of AI in the imaging field of rectal cancer, emphasizing the performance reporting design based on the quality of the dataset, model performance, and external validation. RESULTS: AI-driven tumor segmentation has demonstrated promising results using various convolutional neural network models. AI-based predictions of staging and treatment response have exhibited potential as auxiliary tools for personalized treatment strategies. Some studies have indicated superior performance than conventional models in predicting microsatellite instability and KRAS status, offer-ing noninvasive and cost-effective alternatives for identifying genetic mutations. CONCLUSION: Image-based AI studies for rectal can-cer have shown acceptable diagnostic performance but face several challenges, including limited dataset sizes with standardized data, the need for multicenter studies, and the absence of oncologic relevance and external validation for clinical implantation. Overcoming these pitfalls and hurdles is essential for the feasible integration of AI models in clinical settings for rectal cancer, warranting further research.

Long-term clinical outcomes after high and low ligations with lymph node dissection around the root of the inferior mesenteric artery in patients with rectal cancer.

PURPOSE: This study aimed to evaluate the long-term clinical outcomes based on the ligation level of the inferior mesenteric artery (IMA) in patients with rectal cancer. METHODS: This was a retrospective analysis of a prospectively collected database that included all patients who underwent elective low anterior resection for rectal cancer between January 2013 and December 2019. The clinical outcomes included oncological outcomes, postoperative complications, and functional outcomes. The oncological outcomes included overall survival (OS) and relapse-free survival (RFS). The functional outcomes, including defecatory and urogenital functions, were analyzed using the Fecal Incontinence Severity Index, International Prostate Symptom Score, and International Index of Erectile Function questionnaires. RESULTS: In total, 545 patients were included in the analysis. Of these, 244 patients underwent high ligation (HL), whereas 301 underwent low ligation (LL). The tumor size was larger in the HL group than in the LL group. The number of harvested lymph nodes (LNs) was higher in the HL group than in the LL group. There were no significant differences in complication rates and recurrence patterns between the groups. There were no significant differences in 5-year RFS and OS between the groups. Cox regression analysis revealed that the ligation level (HL vs. LL) was not a significant risk factor for oncological outcomes. Regarding functional outcomes, the LL group showed a significant recovery in defecatory function 1 year postoperatively compared with the HL group. CONCLUSION: LL with LNs dissection around the root of the IMA might not affect the oncologic outcomes comparing to HL; however, it has minimal benefit for defecatory function.

Comparison of postoperative urinary and sexual functions in men who underwent Denonvilliers' fascia preservation or intraoperative laparoscopic radical resection for rectal cancer: A meta-analysis of the Chinese population.

Currently, colorectal cancer has the third highest incidence worldwide. As its incidence is increasing, focus on quality of life after laparoscopic radical resection for colorectal cancer has also increased. This study aimed to compare the effects of retention or resection of the Denonvilliers'fascia on urinary and sexual functions in men who underwent laparoscopic radical resection for rectal cancer. Relevant national and international literature databases, including China Knowledge Network, PubMed, Cochrane Library, and Excerpta Medica Database, were searched according to the established retrieval scheme. Review Manager 5.3 was used to analyze data, and the correct effect model was selected based on heterogeneity. In total, 22 studies involving 2255 patients were included in the meta-analysis. The studies were categorized into the experimental and control groups. The incidence of urinary dysfunction was lower in the experimental group than in the control group at 1 and 6 months postoperatively. In terms of sexual function, the experimental group had lower rates of erectile and ejaculatory dysfunctions than the control group at 1, 3, and 6 months and 1 year postoperatively. However, the experimental group had a longer operation time than the control group. No significant differences in incidence of postoperative complications, intra-operative blood loss, and number of lymph nodes dissections were observed between the two groups. Overall, laparoscopic radical resection for rectal cancer with preservation of the Denonvilliers' fascia has been proven effective in improving postoperative urinary and sexual functions in men without affecting the number of lymph nodes dissected and enhancing postoperative quality of life.

Evolution of therapy for locally advanced rectal cancer.

Rectal cancer is a prevalent disease worldwide. The standard treatment of locally advanced rectal cancer (LARC) is preoperative chemoradiotherapy followed by surgery and adjuvant systemic chemotherapy. Studies have been done to determine the best sequence of treatments to improve survival, cure rate and long term toxicity profile. In this paper, we will review the literature regarding the evolution of LARC treatment.

From burden to relief: The economic and quality-of-life advantages of pseudo continent perineal colostomy in ultra-low rectal cancer patients.

BACKGROUND AND OBJECTIVE: Pseudo Continent Perineal Colostomy (PCPC) is an alternative technique to left iliac colostomy (LIC) after abdominoperineal resection for ultra low rectal cancer (ULRC). It allows placing the stoma in the perineum to preserve patients' body image. However, concerns about its impact on quality of life and management costs have limited its adoption. We aimed to compare the early outcomes and financial burden of PCPC and LIC in ULRC patients in Morocco, a low-middle-income country. METHODS: From January 2018 to December 2019, all patients who underwent abdomino-perineal resection (APR) with LIC or PCPC were prospectively enrolled. For each patient, baseline characteristics, and in hospital and 90 days morbidity with a focus on perineal complications were reported. Quality of life (QOL) was assessed using the validated EORTC-C30 and CR29 questionnaires. Financial burden to patients was reported using declarative out-of-pocket costs (OOPC) analysis. RESULTS: Among 49 patients who underwent APR, 33 received PCPC and 16 received definitive LIC. Similar rates of early perineal complications were observed between the two groups (p = 0.49). Readmission rate at POD90 was higher in the LIC-group due to perineal sepsis (p = 0.09). QOL analysis at 6 months revealed that patients with PCPC had a higher global health status (p = 0.006), a better physical functioning and reported fewer symptoms of flatulence and fecal incontinence (p = 0.001). Patients with a LIC reported more financial difficulties with higher median OOPC of stoma management up to €23 versus €0 per month for PCPC (p = 0.0024). PCPC was the only predictive factor of improved patient reported outcomes. CONCLUSIONS: PCPC is a cost-effective alternative to the standard definitive colostomy without alteration of the QOL or additional perineal complications during the first 6 months following the surgery. These findings may help convince surgeons to offer this option to patients refusing definitive LIC.

Role of dynamic contrast-enhanced MRI in predicting severe acute radiation-induced rectal injury in patients with rectal cancer.

OBJECTIVES: To explore the potential of dynamic contrast-enhanced MRI (DCE-MRI) quantitative parameters in predicting severe acute radiation-induced rectal injury (RRI) in rectal cancer. METHODS: This retrospective study enrolled 49 patients with rectal cancer who underwent neoadjuvant chemoradiotherapy and rectal MRI including a DCE-MRI sequence from November 2014 to March 2021. Two radiologists independently measured DCE-MRI quantitative parameters, including the forward volume transfer constant (Ktrans), rate constant (kep), fractional extravascular extracellular space volume (ve), and the thickness of the rectal wall farthest away from the tumor. These parameters were compared between mild and severe acute RRI groups based on histopathological assessment. Receiver operating characteristic curve analysis was performed to analyze statistically significant parameters. RESULTS: Forty-nine patients (mean age, 54 years ± 12 [standard deviation]; 37 men) were enrolled, including 25 patients with severe acute RRI. Ktrans was lower in severe acute RRI group than mild acute RRI group (0.032 min-1 vs 0.054 min-1; p = 0.008), but difference of other parameters (kep, ve and rectal wall thickness) was not significant between these two groups (all p > 0.05). The area under the receiver operating characteristic curve of Ktrans was 0.72 (95% confidence interval: 0.57, 0.84). With a Ktrans cutoff value of 0.047 min-1, the sensitivity and specificity for severe acute RRI prediction were 80% and 54%, respectively. CONCLUSION: Ktrans demonstrated moderate diagnostic performance in predicting severe acute RRI. CLINICAL RELEVANCE STATEMENT: Dynamic contrast-enhanced MRI can provide non-invasive and objective evidence for perioperative management and treatment strategies in rectal cancer patients with acute radiation-induced rectal injury. KEY POINTS: • To our knowledge, this study is the first to evaluate the predictive value of contrast-enhanced MRI (DCE-MRI) quantitative parameters for severe acute radiation-induced rectal injury (RRI) in patients with rectal cancer. • Forward volume transfer constant (Ktrans), derived from DCE-MRI, exhibited moderate diagnostic performance (AUC = 0.72) in predicting severe acute RRI of rectal cancer, with a sensitivity of 80% and specificity of 54%. • DCE-MRI is a promising imaging marker for distinguishing the severity of acute RRI in patients with rectal cancer.