Clinical efficacy and pathological outcomes of transanal endoscopic intersphincteric resection for low rectal cancer

BACKGROUND Transanal endoscopic intersphincteric resection(ISR)surgery currently lacks sufficient clinical research and reporting.AIM To investigate the clinical effectiveness of transanal endoscopic ISR,in order to promote the clinical application and development of this technique.METHODS This study utilized a retrospective case series design.Clinical and pathological data of patients with lower rectal cancer who underwent transanal endoscopic ISR at the First Affiliated Hospital of Xiamen University between May 2018 and May 2023 were included.All patients underwent transanal endoscopic ISR as the surgical approach.We conducted this study to determine the perioperative recovery status,postoperative complications,and pathological specimen charac-teristics of this group of patients.RESULTS This study included 45 eligible patients,with no perioperative mortalities.The overall incidence of early complications was 22.22%,with a rate of 4.44%for Clavien-Dindo grade≥III events.Two patients(4.4%)developed anastomotic leakage after surgery,including one case of grade A and one case of grade B.Postoperative pathological examination confirmed negative circumferential resection margins and distal resection margins in all patients.The mean distance between the tumor lower margin and distal resection margin was found to be 2.30±0.62 cm.The transanal endoscopic ISR procedure consistently yielded high quality pathological specimens.CONCLUSION Transanal endoscopic ISR is safe,feasible,and provides a clear anatomical view.It is associated with a low incidence of postoperative complications and favorable pathological outcomes,making it worth further research and application.

Intersphincteric resection and coloanal anastomosis in the treatment of distal rectal cancers

Objective:In the evolving era of minimal access surgery,low rectal cancers still pose a challenge to laparoscopic or robotic surgeons.Hence,at our institute we intended to demonstrate the oncological efficacy of intersphincteric resection and coloanal anastomosis in the treatment of distal rectal cancers,performing the abdominal part of the procedure which includes rectal mobilization,laparoscopically.Methods:From February 2017 to March 2021,125 patients who had undergone intersphincteric resection and coloanal anastomosis via the perineal approach at Galaxy Care Laparoscopic Institute,Pune,were included in this study.Transabdominal mobilization of the rectum was performed laparoscopically.All patients had a diversion ileostomy and a pelvic drain.Patients were followed-up for a period of 18 months post-surgery.Data on clinical and oncological outcomes were collected and analysed.The pre-operative and post-operative Wexner incontinence scores were compared.Results:The mean time taken for surgery was 181.57±30.00 min.The mean blood loss was 119.76±42.53 mL.Most patients(103,82.4%)had their tumour at a distance of 1e2 cm from the anal verge.A loco-regional recurrence rate of 12.8%(16/125)was noted in our study.For the post-surgery Wexner score,74.4% of patients(93/125)had a score of 5 or less,depicting that three-quarters of the study population had satisfactory continence.Overall,81.6%of patients were satisfied with the functional results of surgery.Conclusion:Intersphincteric resection and coloanal anastomosis,with a 12.8%recurrence rate,can now be considered an oncological and technically feasible procedure with sphincter salvage and good continence.

Long-term outcomes and failure patterns after laparoscopic intersphincteric resection in ultralow rectal cancers

BACKGROUND Intersphincteric resection(ISR),the ultimate anus-preserving technique for ultralow rectal cancers,is an alternative to abdominoperineal resection(APR).The failure patterns and risk factors for local recurrence and distant metastasis remain controversial and require further investigation.AIM To investigate the long-term outcomes and failure patterns after laparoscopic ISR in ultralow rectal cancers.METHODS Patients who underwent laparoscopic ISR(LsISR)at Peking University First Hospital between January 2012 and December 2020 were retrospectively reviewed.Correlation analysis was performed using the Chi-square or Pearson's correlation test.Prognostic factors for overall survival(OS),local recurrence-free survival(LRFS),and distant metastasis-free survival(DMFS)were analyzed using Cox regression.RESULTS We enrolled 368 patients with a median follow-up of 42 mo.Local recurrence and distant metastasis occurred in 13(3.5%)and 42(11.4%)cases,respectively.The 3-year OS,LRFS,and DMFS rates were 91.3%,97.1%,and 90.1%,respectively Multivariate analyses revealed that LRFS was associated with positive lymph node status[hazard ratio(HR)=5.411,95%confidence interval(CI)=1.413-20.722,P=0.014]and poor differentiation(HR=3.739,95%CI:1.171-11.937,P=0.026),whereas the independent prognostic factors for DMFS were positive lymph node status(HR=2.445,95%CI:1.272-4.698,P=0.007)and(y)pT3 stage(HR=2.741,95%CI:1.225-6.137,P=0.014).CONCLUSION This study confirmed the oncological safety of LsISR for ultralow rectal cancer.Poor differentiation,(y)pT3 stage,and lymph node metastasis are independent risk factors for treatment failure after LsISR,and thus patients with these factors should be carefully managed with optimal neoadjuvant therapy,and for patients with a high risk of local recurrence(N+or poor differentiation),extended radical resection(such as APR instead of ISR)may be more effective.

Narrow pelvic inlet plane area and obesity as risk factors for anastomotic leakage after intersphincteric resection

BACKGROUND Intersphincteric resection(ISR)has been increasingly used as the ultimate sphincter-preserving procedure in extremely low rectal cancer.The most critical complication of this technique is anastomotic leakage.The incidence rate of anastomotic leakage after ISR has been reported to range from 5.1%to 20%.AIM To investigate risk factors for anastomotic leakage after ISR based on clinicopathological variables and pelvimetry.METHODS This study was conducted at Department of Colorectal Surgery,Japanese Red Cross Medical Center,Tokyo,Japan,with a total of 117 patients.We enrolled 117 patients with extremely low rectal cancer who underwent laparotomic and laparoscopic ISRs at our hospital.We conducted retrospective univariate and multivariate regression analyses on 33 items to elucidate the risk factors for anastomotic leakage after ISR.Pelvic dimensions were measured using threedimensional reconstruction of computed tomography images.The optimal cutoff value of the pelvic inlet plane area that predicts anastomotic leakage was determined using a receiver operating characteristic(ROC)curve.RESULTS We observed anastomotic leakage in 10(8.5%)of the 117 patients.In the multivariate analysis,we identified high body mass index(odds ratio 1.674;95%confidence interval:1.087-2.58;P=0.019)and smaller pelvic inlet plane area(odds ratio 0.998;95%confidence interval:0.997-0.999;P=0.012)as statistically significant risk factors for anastomotic leakage.According to the receiver operating characteristic curves,the optimal cutoff value of the pelvic inlet plane area was 10074 mm2.Narrow pelvic inlet plane area(≤10074 mm2)predicted anastomotic leakage with a sensitivity of 90%,a specificity of 85.9%,and an accuracy of 86.3%.CONCLUSION Narrow pelvic inlet and obesity were independent risk factors for anastomotic leakage after ISR.Anastomotic leakage after ISR may be predicted from a narrow pelvic inlet plane area(≤10074 mm2).

Anal Sphincter Function after Intersphincteric Resection for Low Rectal Cancer

Objective： To assess the anal sphincter function after intersphincteric resection for low rectal cancer by questionnaire and vectorial manometry. Methods： twenty five patients underwent intersphincteric resection, the controls contained 25 patients of rectal cancer who underwent low anterior resection and 25 healthy people. The therapeutic responses were evaluated using the Vaizey and Wexner scoring systems and vectorial manometry. Results： The Vaizey and Wexner scores after intersphincteric resection were significantly higher than those of low anterior resection controls at one month, but had no significant difference one year after. On the other hand, the indexes of vectorial manometry still had significant difference one year later. The indexes after intersphincteric resection could not reach the normal level. Conclusion： The anal sphincter function after intersphincteric resection is lower than that after low anterior resection in short term, although the long-term results can be accepted, it still can not reach the normal level.

Preservation of the continence function after intersphincteric resection using a prolapsing technique in the patients with low rectal cancer and its clinical prognosis

Background The technique of intersphincteric resection of tumors combined with coloanal anastomosis has been used to avoid permanent colostomy for patients with a rectal cancer located 〈5 cm from the anal verge. This study aimed at assessing the preservation of continence function of the residual rectum and the clinical prognosis of patients with lower rectal cancer after intersphincteric resection using a prolapsing technique. Methods This study included patients with the following inclusion criteria： （1） pathological evidence of rectal cancer and the tumors within distal margins located 5 cm or less from the anus by preoperative endoscopic examination; （2） no evidence by MRI of infiltration of either the external sphincter, puborectalis or the levator muscle; （3） the patients are eligible for intersphincteric resection and lower coloanal anastomosis with a preoperative biopsy showing the tumors with well-to-moderate differentiation. From January 2000 to June 2004, 23 patients with low rectal cancer were included in this study. We used the standard abdominoperineal approach to perform radical resection of tumors with excision of the mesorectum and total or part of the internal sphincters. The patients were followed for assessment of the function of the residual rectum and of cancer recurrence after the operations. Results The median tumor distance from the anal margin was 4.5 （range 3.5-5.0） cm and the mean distal surgical margin 1.6 （range 1.0-2.0） cm. Cancer was classified into Stage Ⅰ （30.4%）, Stage Ⅱ （47.8%）, and Stage Ⅲ （21.7%） according to the TNM classification. Two patients developed anastomotic fistula after the surgical resection and 2 patients （8.7%） developed later stages of anastomotic stricture at the site of coloanal anastomosis. The median follow-up period was 31.5 months （range 12-54） and 2 patients （8.7%） developed local recurrence. Three deaths were associated with distal organ metastasis. Twenty patients （87.0%） have maintained competence to control solid or liquid stool and the capacity of flatus continence after the surgery. Among these patients, 2 patients were able to control solid stool and occasionally lose continence of liquid stool. And only 1 patient （4.4%） has retained partial rectum function with good continence of solid stool but not liquid after the operations. Average times of defecation per day of 3, 6, 12, 24 and 36 months after the surgery were 13.1, 4.7, 3.1, 2.9, and 3.2 times/day. Anal manometer measurements showed a decrease of pressure during the resting time after intersphincteric resection and this change remained during the period of follow-up. The maximum squeeze pressure was improved after an initial decrease after the surgery. Conclusions More residual rectum function after the surgery may be preserved by intersphincteric resection of low rectum cancer. At the same time this technique is safe with few postoperative complication and low tumor recurrence after the surgery.

Simple instruments facilitating achievement of transanal total mesorectal excision in male patients

AIM To assess the efficacy of a modified approach with transanal total mesorectal excision(ta TME) using simple customized instruments in male patients with low rectal cancer.METHODS A total of 115 male patients with low rectal cancer from December 2006 to August 2015 were retrospectively studied. All patients had a bulky tumor(tumor diameter ≥ 40 mm). Forty-one patients(group A) underwent a classical approach of transabdominal total mesorectal excision(TME) and transanal intersphincteric resection(ISR), and the other 74 patients(group B) underwent a modified approach with transabdominal TME,transanal ISR, and ta TME. Some simple instruments including modified retractors and an anal dilator with a papilionaceous fixture were used to perform ta TME. The operative time, quality of mesorectal excision, circumferential resection margin, local recurrence, and postoperative survival were evaluated.RESULTS All 115 patients had successful sphincter preservation. The operative time in group B(240 min, range: 160-330 min) was significantly shorter than that in group A(280 min, range: 200-360 min; P = 0.000). Co m pa r e d w it h g r o up A, m o r e c o m p le t e d is t a l mesorectum and total mesorectum were achieved in group B(100% vs 75.6%, P = 0.000; 90.5% vs 70.7%, P = 0.008, respectively). After 46.1 ± 25.6 mo followup, group B had a lower local recurrence rate and higher disease-free survival rate compared with group A, but these differences were not statistically significant(5.4% vs 14.6%, P = 0.093; 79.5% vs 65.1%, P = 0.130). CONCLUSION Retrograde ta TME with simple customized instruments can achieve high-quality TME, and it might be an effective and economical alternative for male patients with bulky tumors.