ObjectiveTo evaluate the postoperative anal function of rectal cancer patients treated with transanal total mesorectal excision (taTME), and to analyze the influencing factors which resulted in low anterior resection syndrome (LARS) after taTME in this paper, so as to provide guidance for clinical practice.MethodsThe data about the patients with rectal cancer treated with taTME were collected at the Affiliated Nanchong Central Hospital of North Sichuan Medical College from December 2018 to December 2019, including the clinical data and follow-up data. Postoperative recovery condition of the patients’ anal function and the affecting factors caused the occurrence of severe LARS after taTME were analyzed. The patients’ anal function within 1, 6, and 12 months after taTME were evaluated, and the evaluation tools were LARS scale and Wexner scale. The follow-up period was up to December 30, 2020.ResultsA total of 67 patients were completed preoperative and postoperative follow-up at 1, 6, and 12 months. In terms of anal function, within 1 month after taTME was the worst period in which the anal function was the worst among all the points of time evaluated (1.49±0.33, 10.28±0.64, 6.42±0.60, and 3.73±0.61, respectively), and there was time trend during the follow-up period (F=66.101, P<0.001). In the first year after taTME, the patient’s anal function was in a state of continuous recovery, and the differences between the three points of time at 1, 6, and 12 months after taTME and preoperative anal function were statistically significant (P<0.010). The results of multivariate analysis indicated that the distance between the anastomotic stoma and the anal verge was independent risk factor affecting the postoperative anal function of the patients with taTME at 1 month and 6 months (P<0.010).ConclusionsWith time going, the postoperative anal function of the patients with taTME can be recovered to a certain extent. The distance between the anastomotic stoma and the anal verge was the independent factor affecting the postoperative function of the rectal cancer patients received taTME.
Objective To investigate the key risk factors for low anterior resection syndrome (LARS) within 6 months after rectal cancer surgery and to construct a risk prediction model based on the random forest algorithm, providing a reference for early clinical intervention. Methods A retrospective study was conducted on patients who underwent rectal cancer surgery at the West China Hospital of Sichuan University from January 2020 to August 2021. A prediction model for the occurrence of LARS within 6 months after rectal cancer surgery was constructed using the random forest algorithm. The dataset was divided into a training set and a test set in an 8∶2 ratio. The model performance was evaluated by accuracy, sensitivity, specificity, area under the receiver operating characteristic curve (AUC), Brier score, and decision curve analysis (DCA). Results A total of 394 patients were enrolled. Among the 394 patients, 106 developed LARS within 6 months after surgery, with an incidence rate of 26.9%. According to the importance ranking in the random forest algorithm, the key predictive factors were: distance from the inferior tumor margin to the dentate line, body mass index (BMI), tumor size, time to first postoperative flatus, operation time, age, neoadjuvant therapy, and TNM stage. The prediction model constructed using these key factors achieved the accuracy of 73.4%, sensitivity of 75.0%, specificity of 72.7%, AUC (95% confidence interval) of 0.801 (0.685, 0.916), and the Brier score of 0.198. DCA showed that the model provided favorable clinical benefit when the threshold probability was between 25% and 64%. Conclusions The results of this study suggest that patients with a shorter distance from the tumor to the dentate line, higher BMI, and larger tumor size are at higher risk of developing LARS. The risk prediction model constructed in this study demonstrates a good predictive performance and may provide a useful reference for early identification of high-risk patients after rectal cancer surgery.
Objective To explore the impact of the severity of low anterior resection syndrome (LARS) on the quality of life in patients with rectal cancer. Methods Literatures published from January 2012 to August 2020 in the Cochrane Library, PubMed, Embase, CNKI, WanFang and other databases were searched according to the search terms. Study screened, data extracted, and quality evaluated were conducted by three reviewers independently, and the RevMan 5.4 software was used for meta-analysis. Results Seven studies, involving 1 616 patients were included. Meta-analysis results showed that the functional scores (including overall health status, physiological functioning, role functioning, emotional functioning, cognitive functioning, and social functioning) of patients with major LARS were lower than those of patients with no/minor LARS (P<0.001). Except for appetite loss, the symptom score (including fatigue, nausea and vomiting, pain), shortness of breath, insomnia, constipation, diarrhea, and financial difficulties of patients with major LARS were higher than those of patients with no/minor LARS (P<0.01). Conclusion Major LARS has a greater impact on the quality of life of patients after surgery than no/minor LARS.
Objective To explore the impact of preventive stoma on the occurrence and development trajectory of low anterior resection syndrome (LARS) following rectal cancer surgery. MethodsA retrospective cohort study design was employed to collect clinical data from 540 patients who underwent rectal cancer resection at West China Hospital, Sichuan University between April 2018 and June 2022. Patients were categorized into stoma group (n=275) and non-stoma group (n=265) based on the presence or absence of preventive stoma. Generalized estimating equation was used to analyze the impact of stoma-related factors (presence of stoma, stoma type, and interval to stoma closure) on the occurrence of LARS at 1, 3, 6, 9, and 12 months postoperatively. Latent class growth modeling was employed to identify LARS development trajectories, and multi-class logistic regression was used to assess the influence of stoma-related factors on LARS trajectory categories. ResultsThe incidence of LARS showed an overall downward trend within 12 months postoperatively, the incidence rates at 1, 3, 6, 9, and 12 months after operation were 46.3% (250/540), 36.5% (197/540), 27.8% (150/540), 23.0% (124/540) and 16.9% (91/540), respectively. Generalized estimating equation analysis revealed that preventive stoma (OR=1.410, P=0.283), stoma type (OR=1.375, P=0.099), and interval to stoma closure (OR=0.999, P=0.502) were not independent predictors of LARS occurrence. Conversely, at various postoperative time points, educational level (junior college vs. bachelor’s degree or higher: OR=1.834, P=0.039), TNM (stage 2 vs. stage 4: OR=0.533, P=0.016; stage 3 vs. stage 4: OR=0.556, P=0.015), tumor length (OR=1.316, P=0.015), tumor width (OR=0.707, P=0.009), and surgical procedure (ultra-low anterior resection vs. coloanal anastomosis/colon anal anastomosis: OR=2.076, P=0.017) were closely associated with the occurrence of LARS. Latent class growth modeling identified three LARS trajectory categories: low symptom burden–rapid improvement group (286 cases, 53.0%), high symptom burden–slow improvement group (163 cases, 30.2%), and high symptom burden–persistent impairment group (91 cases, 16.8%). Multi-class logistic regression analysis revealed that the presence or absence of preventive stoma was not a predictive factor for LARS trajectory category (high symptom burden–slow improvement group: OR=0.739, P=0.407; high symptom burden–persistent impairment group: OR=0.693, P=0.400). However, patients undergoing ultra-low anterior resection were more likely to be assigned to the high symptom burden-slow improvement group (OR=2.677, P=0.026).ConclusionsPreventive stoma is not an independent risk factor for the occurrence or trajectory of LARS. The occurrence of LARS is associated with the tumor’s biological characteristics, surgical approach, and postoperative time, moreover, the surgical approach is a key factor influencing the progression of LARS.