External sphincter resection for lower rectal and anal canal adenocarcinoma: achieving anal preservation with oncological and functional satisfaction

Conformal sphincteric resection for ultra-low rectal cancer located below the dentate line: A pilot report

AIM

Sphincter-sparing surgery can be achieved in most cases of low rectal cancer with the development of intersphincteric resection. However, abdominoperineal resection is still inevitable for patients with tumours located below the dentate line. To address this, we have developed a procedure called conformal sphincteric resection (CSR) in which the corresponding part of the subcutaneous portion of the external anal sphincter and the perianal skin on the tumour side is removed to achieve a safe distal resection margin and lateral resection margin while the dentate line and the internal anal sphincter on the tumour-free side are preserved as much as possible, to achieve sphincter preservation without compromising oncological safety and functional acceptability, and to render tumour location no longer a contraindication for sphincter-sparing surgery. This is the first study to describe the concept, indication and surgical procedure of CSR and to report its preliminary surgical, oncological and functional results.

METHODS

This is a retrospective, single-centre, single-arm pilot study conducted at Huashan Hospital, Fudan University. Demographic, clinicopathological, oncological and functional follow-up data were collected from 20 consecutive patients with rectal tumours located below the dentate line who underwent laparoscopic CSR by the same surgical team from June 2018 to March 2022.

RESULTS

The mean distance of the tumour's lower edge from the anal verge was 13.1 ± 6.0 mm. The mean distal resection margin was 10.6 ± 4.3 mm. All circumferential resection margins were negative. There were no instances of perioperative mortality. The complication rate was 25% but all were Clavien-Dindo Grade I. Among the 20 cases, 17 were diagnosed with adenocarcinoma, one with squamous cell carcinoma and two with adenoma featuring high-grade intraepithelial neoplasia. Pathological TNM staging revealed two, seven, five, five and one case(s) in Stages 0, I, II, III and IV, respectively. The median follow-up period was 20 months (interquartile range 22 months), with no withdrawals. The overall and disease-free survival rates were both 95%. The mean Wexner incontinence score and low anterior resection syndrome score recorded 18 months following diverting ileostomy closure were 6.3 ± 3.8 and 27.3 ± 3.6, respectively.

CONCLUSIONS

This study has proposed the CSR procedure for the first time, which is a technically feasible, oncologically safe and functionally acceptable procedure for carefully selected patients with rectal tumours located below the dentate line.

Comparison of long-term quality of life based on surgical procedure in patients with rectal cancer

Introduction

Reports on the long-term quality of life (QOL) over 3 years after surgery in patients who have undergone surgery for rectal cancer are limited. Therefore, we aimed to evaluate the long-term QOL of patients who underwent high anterior resection (HAR), low anterior resection (LAR), internal sphincter resection (ISR), or abdominoperineal resection (APR) for rectal cancer.

Methods

A questionnaire regarding QOL was sent to 360 patients with rectal cancer who underwent curative resection by HAR, LAR, ISR, or APR between January 2005 and December 2015. QOL was assessed using the short-form 36 (SF-36) and modified fecal incontinence QOL (mFIQL) questionnaire. QOL between surgical procedures was analyzed using a multivariate model adjusted for age, sex, and postoperative time.

Results

A total of 144 patients responded with a median follow-up period of 94 months (range 38-233 months). According to surgical procedure, HAR was performed in 26 patients, LAR in 80 patients, ISR in 32 patients, and APR in 6 patients. Patients who underwent HAR had significantly better mFIQL scores than those who underwent LAR and ISR (p=0.013 and p=0004, respectively) and significantly better role/social component summary scores on the SF-36 subscales (p=0.007). No difference was observed in the mFIQL scores between patients who underwent ISR and those who underwent APR (p=0.8423). In addition, postoperative anastomotic leakage sutures did not influence the mFIQL and SF-36 scores after surgery.

Conclusion

The QOL of patients who underwent anus-preserving surgery was best in the HAR group, with the QOL of other groups similar to the APR group. These results suggest that anus- preserving surgery is acceptable from a QOL standpoint. However, a colostomy may be a more satisfactory procedure in some patients.

Critical and Challenging Issues in the Surgical Management of Low-Lying Rectal Cancer

Despite innovative advancements, the management of distally located rectal cancer (RC) remains a formidable endeavor. The critical location of the tumor predisposes it to a circumferential resection margin that tends to involve the sphincters and surrounding organs, pelvic lymph node metastasis, and anastomotic complications. In this regard, colorectal surgeons should be aware of issues beyond the performance of total mesorectal excision (TME). For decades, abdominoperineal resection had been the standard of care for low-lying RC; however, its association with high rates of tumor recurrence, tumor perforation, and poorer survival has stimulated the development of novel surgical techniques and modifications, such as extralevator abdominoperineal excision. Similarly, difficult dissections and poor visualization, especially in obese patients with low-lying tumors, have led to the development of transanal TME or the "bottom-to-up" approach. Additionally, while neoadjuvant chemoradiotherapy has allowed for the execution of more sphincter-saving procedures without oncologic compromise, functional outcomes remain an issue. Nevertheless, neoadjuvant treatment can lead to significant tumor regression and complete pathological response, permitting the utilization of organ-preserving strategies. At present, an East and West dualism pervades the management of lateral lymph node metastasis, thereby calling for a more global and united approach. Moreover, with the increasing importance of quality of life, a tailored, individualized treatment approach is of utmost importance when taking into account oncologic and anticipated functional outcomes.

Functional outcomes after intersphincteric resection for ultralow rectal cancer

Anal function is one of the most important parameters for evaluating the efficacy of intersphincteric resection (ISR) for the treatment of ultralow rectal cancer (< 1 cm from the anal sphincter). Although there have been no results hitherto from randomized controlled trials to verify the clinical benefits of the ultimate sphincter-sparing technique, increasing evidence demonstrates that ISR significantly decreases the rate of permanent stoma and patients could acquire satisfied functional results after surgery. This review discusses the short-term and long-term functional outcomes, risk factors for anal incontinence, and surgical method and approach of ISR.

Intersphincteric resection for low rectal cancer

For low rectal cancer located < 5 cm from the anal verge, abdominoperineal resection (APR) with permanent sigmoid colostomy is usually used to ensure the R0 resection. Sphincter saving surgery has emerged in the last 20 years, and the introduction of intersphincteric resection (ISR) can successfully preserve the anal function and guarantee a radical tumor resection for patients with ultra-low lying tumors. Therefore, the use of APR has been consistently declining worldwide. Recently, a growing body of research on ISR has been reported. However, more evidence based results are needed to clarify some issues about ISR. In the current review, we discuss the indications for ISR and the oncological and functional outcomes following the procedure. Some technique issues of ISR are also discussed.

Transanal Pull-Through Procedure with Delayed versus Immediate Coloanal Anastomosis for Anus-Preserving Curative Resection of Lower Rectal Cancer: A Case-Control Study

This case-control study compared the effectiveness and safety of transanal pull-through procedure (TPP) with delayed or immediate coloanal anastomosis (CAA) for anus-preserving curative resection of lower rectal cancer. Lower rectal cancer patients (n = 128) were hospitalized between January 2003 and December 2013 for elective anus-preserving curative resection through a TPP with delayed (n = 72) or immediate (n = 56) CAA. Main outcome measures including surgical safety, resection radicality, and defecation function were assessed. The two groups were comparable in age, sex, gross pathology, histology, and tumor-node-metastasis staging. Both the delayed and immediate CAA TPPs had similar resection radicality and safety profiles. The immediate CAA was associated with a significantly higher risk of anastomotic leakage and defecation impairment. None of patients in the delayed CAA group experienced anastomotic leakage. In conclusion, TPP with delayed CAA may be superior to immediate CAA in minimizing the risk of anastomotic leakage and relevant surgical morbidities, and does not require a temporary ileostomy and second-look restoration of ostomy.