Intersphincteric Resection Is the Optimal Procedure for Very Low Rectal Cancer: Techniques, Morbidity, Oncologic and Functional Outcomes

Background: The intersphincteric resection the most extreme form of a sphincter-preserving alternative for the abdominoperineal resection. Aim of the Work: We investigated oncological, functional outcomes and morbidity after ISR. Methods: This retrospective study included 164 patients who underwent ISR with between 2010 and 2015, Male 56.1%, Female 43.9%, with a median age was 54.5 years, Median follow-up time was of 48 months, Average surgical time was 230 min, Median blood loss was 700 mL and median hospital stay was nine days. Mean tumour size was 34 mm. The surgical procedure through a laparotomy (72.6%), laparoscopically (27.4%). Neoadjuvant radiotherapy 89.6% {long-course radiotherapy 74.4%, short-course radiotherapy 15.2%}, neoadjuvant chemotherapy 28.7% and adjuvant chemotherapy 70.1%. Colonic J-pouch 16.5%, Transverse coloplasty 15.9%, a side-to-end anastomosis 26.8% and straight coloanal anastomosis 40.9%. Partial-ISR 36.6%, subtotal-ISR 37.2%, total-ISR 26.2%, diverting ileostomy 6.7%. Results: Operative mortality 1.2%, morbidity 14.6% (anastomotic leakage 3.7%, anastomotic stenosis 1.8%, a recto-vaginal fistula 2.4% bowel obstruction 3%, surgical site infection 3%. Respiratory tract infection 1.2%, local 7.9%, distant recurrence 15.2%, 5-year overall 79.8%, disease-free survival 75.8%, R0 resection 95.1%. Pathologic complete response 11%. Circumferential margin involvement 2.4%. Median number of lymph nodes 17. Mean distal margin 20 mm, after 12 months Median Wexner score 6. Incontinence for (flatus 11%, liquid 4.9%, solid 4.3%). Median bowel motions in a 24-h were 3. Faecal urgency 17.7%. Stool fragmentation 18.9%. Difficult evacuation 17.7%, lifestyle How to cite this paper: Zedan, A., Tawfik, A., Aboeleupn, E., Salah, A. and Morsy, A. (2019) Intersphincteric Resection Is the Optimal Procedure for Very Low Rectal Cancer: Techniques, Morbidity, Oncologic and Functional Outcomes. Journal of Cancer Therapy, 10, 400-410. https://doi.org/10.4236/jct.2019.105033 Received: April 17, 2019 Accepted: May 28, 2019 Published: May 31, 2019 Copyright © 2019 by author(s) and Scientific Research Publishing Inc. This work is licensed under the Creative Commons Attribution International License (CC BY 4.0). http://creativecommons.org/licenses/by/4.0/ Open Access


Introduction
Abdominoperineal resection (APR) since miles 1908 for distal rectal cancer associated with high local recurrence rates, permanent colostomy has a poor quality of life, now indicated only in External sphincter infiltration. Total mesorectal excision (TME) in 1982 by Heald consider gold standard of surgical technique for rectal cancer which results in improved survival and reduced local recurrence [1] [2] [3].
Neoadjuvant chemoradiotherapy down-sizing of tumour and down-staging of disease reduces local recurrence by up to 50%, facilitating sphincter sparing surgery [1] [3] [4]. Circumferential margin involvement (CRM) involvement is a strong predictor of local recurrence, survival rates. A distal margin of a 1 cm DRM is adequate [5] [6].
Rudolf Schiessel developed the intersphincteric resection (ISR) followed by hand-sewn coloanal anastomosis technique in 1994, on this basis, an embryonic plane between the viscera and the surrounding skeletal muscles. It was reported to be safe in terms of leakage and mortality. ISR is defined as the ultimate anal preservation surgery by both abdominal and anal approaches which consist of TME and excision of the internal anal sphincter.
Saito et al. reported no differences in the overall survivals and the disease-free survivals between the ISR and the APR groups. There are three types of ISR, a neorectum reservoir allow early preservation of function [7] [8].
The aim of this paper is to evaluate morbidity, oncologic and functional outcomes after ISR.

Nature of Study and Patient Selection
Between January 2010 and January 2015, we retrospectively collected data on 164 patients with pathologic-proven rectal cancer who underwent ISR at Surgical Oncology Department of South Egypt Cancer Institute, Assiut University, Egypt. A complete history and physical examination, CEA levels, full colonoscopy, Pelvi-abdominal MRI/CT and Chest X-Ray were performed. Patients with stage IV rectal cancer were excluded from this study along with those with proved positive surgical margin involved by the tumor and patients undergoing APR for tumors that reached to the DRMs.

Neoadjuvant Chemoradiation
Neoadjuvant chemoradiotherapy for T3 disease or above/presence of pathological nodes, short-course radiotherapy (25 Gy; administered as five daily fractions  The first step of the perineal part of the operation is a good exposition of the anal canal; Saline adrenaline solution was injected sub-mucosally just distal to the dentate line. Figure 2(N) the mucosa and internal sphincter are circumferentially incised facilitates the exposure of the internal sphincter Figure 2(G), total-ISR The internal sphincter is completely removed, subtotal-ISR a two-third resection of the IAS and partial-ISR one-third resection of the upper part of the IAS, The anal orifice is then closed transanally with pursestring sutures Figure 2(P). Dissection was then carried out between internal and external sphincter till the level of pelvic floor. The distal rectal margin were examined with frozen sections, the rectum was removed transanally Figure 2(A).
Restoration of intestinal continuity is achieved with a handsewn coloanal anastomosis Figure

Adjuvant Therapy
Patients with T3, T4, and/or node-positive disease received postoperative adjuvant chemotherapy; FOLFOX was repeated every two weeks for 24 weeks.

Statistical Methods
SPSS (Statistical Package for the Social Science) was used for data management. Mean and standard deviation described quantitative data and counted with percentages for qualitative data. For this retrospective cohort study, data were abstracted from patients' records. Disease-free survival was calculated from the date of curative surgery up to first evidence of either local recurrence of distant metastasis or both. Overall survival was calculated from date of pathologic diagnostic confirmation to date of death or last followed up. For patients who lost follow with advanced state telephone calls were done to assess the occurrence of death. Kaplan Meier methods were used to estimate survival.

Sociodemographic and Clinical Characteristics
This study included a total number of 164 cases: 92 males and 72 females with a mean age of 54.5 years. Table 1 illustrates sociodemographic and clinical characteristics of the patients. Median follow-up time was of 48 months (range 21 to 120 months). Mean distance from the anal verge to the distal tumour edge was 4.1 cm (2.9 to 6 cm).

Post-Operative Morbidity & Management
Two deaths (1.2%) occurred, one due to myocardial infarction, one patient who had anastomotic leakage and sepsis Figure 2
The 5-year overall and disease-free survival rates were 79.8% and 75.8%, respectively.
Martin et al. the 5-year disease-free survival rate was 78.6% and the 5-year overall survival was 86.3% [15]. Oncological outcomes after ISR were not markedly different from those after APR with ranges of 68% -86% and 76% -97%, respectively. In our study, 5-year overall survival was 79.8% with 5-year disease-free survival (DFS) being 75.8%.

Conclusion
Intersphincteric resection (ISR) is a feasible, effective, safe and valuable procedure with acceptable oncologic and functional outcomes for sphincter saving approach in selected patients with distal rectal carcinomas.