Sphincter-saving surgeries for rectal cancer: A single center study from Kashmir.

SUMMARY AND BACKGROUND DATA: The goals in the treatment of rectal cancer are cure, local control, and preservation of sphincter, bladder and sexual function. Surgical resection using sharp mesorectal dissection is important for achieving these goals.
OBJECTIVES: The current treatment of choice for carcinoma rectum is sphincter saving procedures, which have practically replaced the previously done abdominoperineal resection. We performed a study in our institute to evaluate the surgical outcome and complications of rectal cancer.
MATERIALS AND METHODS: This prospectivestudy included 117 patients, treated for primary rectal cancer by low anterior resection (LAR) from May 2007 to December 2010. All patients underwent standard total mesorectal excision (TME) followed by restoration of continuity.
RESULTS: The peri-operative mortality rate was 2.5% (3/117). Post-operative complications occurred in 32% of the patients. After a median follow up of 42 months, local recurrences developed in 6 (5%) patients and distant metastasis in 5 (4.2%). The survival rate was 93%.
CONCLUSION: The concept of total mesorectal excision (TME), advances in stapling technology and neoadjuvant therapy have made it possible to preserve the anal sphincter in most of the patients. Rectal cancer needs to be managed especially in a specialized unit for better results.

Introduction

Colorectal cancer is one of the major causes of death worldwide and ranks third in the order.[1] Surgical resection using sharp mesorectal dissection [Figure 1] is important for achieving cure, with preservation of sphincter and sexual function. The advent of staplers has increased the number of patients being benefitted by sphincter preserving surgery.[2] Neoadjuvant therapy has also helped in tumor down staging, thereby reducing the number of patients with permanent stoma.[3] The concept of total mesorectal excision (TME) proposed by Heald has been shown to improve both disease free survival and overall survival.[4] Rectal cancer is on the rise in the valley of Kashmir, therefore the present study was undertaken with a view to assess the outcome of surgery in patients undergoing low anterior resection (LAR) for carcinoma rectum in this part of the world vis-à-vis rest of the world.

Figure 1

Stenosing rectal growth

Material and Methods

In a prospective study conducted over a period of three and a half years, 117 patients were enrolled. After proper approval from the ethics committee, a detailed history and general physical examination and evaluation were carried as per preset proforma. Anemia and poor nutritional status were addressed preoperatively. Diagnosis was confirmed by histopathology after endoscopic biopsy of the lesion. contrast enhanced computed tomography (CECT) or magnetic responance imaging (MRI) was done to assess the local status and distant spread of the lesion. Patients with unresectable tumors, distant metastasis, and growth below 4 cms from anal verge were excluded from the study.

Surgical technique

Except in nine patients in whom laparoscopic technique was used, in all other patients surgery was performed by the open method using conventional midline infra umbilical incision. Procedures like anterior resection (AR), i.e., resection of growth was done above the peritoneal reflections, low anterior resection LAR, which is defined as the resection of growth between 4-11 cms from anal verge and ultraLAR, i.e., when the distal margin of resection is less than 4 cms from anal verge, were performed depending upon the level of lesion from the anal verge, using the standard mesorectal excision technique. The gut continuity was restored by the stapling technique. In patients with ultra low anastomosis and those at high risk, a covering ileostomy was done routinely and closed after 812 weeks. Intra-operatively every attempt was made to stick to the oncological principles.

Neoadjuvant therapy was given to those patients with serosal infiltration and/or lymph node involvement. Patients with stage III, stage IV, and some patients with high risk stage II disease received adjuvant therapy. Patients were followed regularly as per standard protocol for results and complications of surgery. Initial follow-up was weekly for the first month, monthly for the next 6 months, and three monthly thereafter. The results were compiled and analyzed statistically using descriptive statistics, Chi-square test, and KaplanMeyer for survival analysis.

Results

Between May 2007 and Dec 2010, there were 117 patients included in the study, with a male:Female ratio of 1.17:1 Thirty-four percent of patients were aged 5160 years with mean age of 52.1 ± 13.9. Our youngest patient was 21 years and the oldest 80 years of age [Table 1].

Table 1

Age and gender distribution of the studied subjects

Seventy-one patients had well differentiated adenocarcinoma, 21 had moderately differentiated adenocarcinoma and there were small numbers of patients with other pathologies [Table 2].

Table 2

Histopathology of the studied patients

Out of 117 patients, 58 (50%) had stage II disease, 42 (36%) stage III, 14 (12%) stage I, and 3 patients had stage IV disease [Table 3]. The neoadjuvant therapy included concurrent radio and chemotherapy (5040 cGy delivered in fractions of 180 cGy per day, 5 days per week) and 5- florouracil (120-hour continuous intravenous infusion during the first and fifth weeks). 64 (55%) patients underwent LAR; 30 (25%) patients ultra- LAR and 23 patients (20%) AR [Table 4]. In 22 patients, colonic pouch was reconstructed. Overall 32% patients developed complications [Table 5], most common being urinary retention (10%). These patients were catheterized for 36 weeks but all of them eventually recovered. Eleven patients developed anastomotic leak out of which six patients needed repeat surgery in the form of abscess drainage and covering ileostomy which was closed after 1220 weeks. Three patients recovered after conservative treatment but two patients succumbed to disseminated sepsis. In addition 4 patients developed radiation enteritis due to radiotherapy.

Table 3

Stage wise distribution of patients

Table 4

Procedure in the studied patients (n=50)

Table 5

Complications

The follow up period ranged from 360 months with a median follow up of 42 months.

One-hundred and twelve (96%) patients were continent and satisfied with their bowel frequency at 42 months of median follow-up. Three (2.5%) patients were incontinent to flatus and two (1.7%) had partial incontinence to liquid feces. Ninety-four (81%) patients including 20 patients with colonic J-pouch had 1-3 motions per day; rest had 4-6 motions per day but stools eventually decreased to 2-4 per day after about 6 months. Three patients in our study developed sexual problems in the form of erectile dysfunction which was ascertained by using international index of erectile function questionnaire (IFEF).

Eleven patients developed recurrence at an average follow-up period of 42 months. Six patients developed local recurrence, three liver metastasis, and two patients developed multiple organ metastases (liver, lung and brain). In three patients repeat LAR was attempted, two underwent abdominoperineal resection (APR), and in one only diverting colostomy could be performed. Nine (7.6%) patients died, three in the immediate post-operative period, one because of pulmonary thromboembolism, and the other two due to post-operative sepsis. Three died during chemotherapy due to sepsis and the other three due to distant metastases, out of which two had liver metastases pre-operatively and were down staged by neo-adjuvant therapy, i.e., concurrent chemo and radio therapy (5040 cGy delivered in fractions of 180 cGy per day, 5 days per week) and 5- florouracil (120-hour continuous intravenous infusion during the first and fifth weeks)

All patients with stage I, 95% with stage II, 90% (38/42) with stage III, and only one out of three (33%) with stage IV disease were alive at a median follow up of 42 months.

According to histology well differentiated, moderately differentiated and poorly differentiated adenocarcinoma had survival of 96.3, 89, and 50%, respectively [Table 6].

Table 6

Outcome w. r. t. Stage and HPE

Discussion

In the treatment of carcinoma of mid and distal rectum, LAR is the mainstay of sphincter preserving-operations. Technical difficulties in patients, who otherwise deserve sphincter-preserving operations, have previously resulted in the use of pull-through procedures in approximately 10% of cases.[5] All these operations involve either significant distortion of the distal rectal segment in order to achieve a primary anastomosis or, alternatively, healing by secondary intention. Both of these circumstances lead to frequent stricture or incontinence, except when the operation is performed by very experienced surgeons.[6] In contrast to the pull-through operations, coloanal or low colorectal reconstruction is a primary end-to-end anastomosis that can be performed with a minimum of anal manipulation and sensory disturbance. Although the risk of pelvic sepsis is lower in this operation than after LAR, a safe period of complete healing is essential to ensure good function. This is best achieved by complete fecal diversion. It is unreasonable to expect normal continence and anorectal function in the immediate post-operative period and long-term functional results are dependent upon the absence of pelvic fibrosis, i.e., healing without sepsis, or hemorrhage. The factors associated with difficulty in sphincter preservation are male sex, morbid obesity, preoperative incontinence, direct involvement of anal sphincter muscles with carcinoma, and bulky tumor within 5 cms from anal verge.[7]

Results of coloanal anastomosis have varied with individual reports. Killing back has reported on 43 cases of coloanal anastomosis, representing 12% of 350 cases of rectal cancer.[8] He reported an operative mortality of 2.3% due to pelvic sepsis. In contrast to our results, at least one-half of his patients wore a pad and were incontinent for flatus. While some patients had only one bowel movement per day, others were vulnerable to “unpredictable bouts of frequency.”

The main post-operative complication in our patients was urinary retention (10%) which is about half as compared to that reported by Enker (19.5%).[9] He also reported a major anastomotic leak rate of 5% compared to 10% in our study. Burt Cagir has reported a urinary dysfunction secondary to weakening of detrusor muscle in 35% patients.[7] In our study, three patients (2.5%) developed impotence due to erectile dysfunction, which in the past has been reported to occur in 570% of men, but recent reports indicate that the current incidence is lower.[10]

Localio reported 14 deaths after 646 operations yielding an overall mortality rate of 2.2%.[11] There were nine deaths (7.6%) post-operatively in our series. A total of 4% mortality rate has been reported after coloanal anastomosis (CAA) by Nicholls.[12]

Shrikhande has reported an overall complication rate of 11.6% (16/138), including five anastomotic leaks, five wound infections, five sunken stomas, and one adhesive intestinal obstruction.[13] There was one case of death in his study.

The anastomotic leak reported by Baren et al. was 2.7%, Moran et al. 9%, Redmond et al. 2.8%, Laxamana et al. 7.3%, and Kanellos et al. 9.7%.[141516171819] It was 9.4% in our study [Table 7]. So in other series the rate of anastomotic leak ranges from 2.7 to 9.7%. No routine radiological examination was made and only symptomatic leaks were taken in to account. The rate of anastomotic leak after LAR is usually 9% except for Localio et al. who reported a rate of 1%.[112024] The risk of leak does not seem to be reduced when stapled anastomosis is performed.[5] The percentage leak in our patients was comparable to other series.[9] In our study one patient developed peritonitis. None of our patients with leak led to permanent functional failure.

Table 7

Comparison of anastomotic leak rates

Functional results of our study were comparable to other studies.[1112262728] Enker reported that nine to twelve months after colostomy closure, 64% of all patients had complete continence and normal bowel habits, with only minor disturbances in anorectal function. Nineteen patients (86%) were completely continent with normal or near normal bowel function.[9] In our study, 8 out of 15 patients who were incontinent after surgery, had improved function at 1 year of mean follow up. This might be because of reappearance of recto-anal inhibitory reflex.[29] The number of stool motions per day in 95 patients were 1-3 and in rest >4. The former group included 20 patients with colonic J- pouch formation. Two patients with J-pouch had difficulty with stool evacuation which needed laxatives and enemas. Our results are comparable to the study by Rouanet in which the stool frequency ranged from 1 every 2 days to 6 daily, with a mean stool frequency of 1.6, depending on the type of surgery performed i.e., one daily stool or constipation after colonic pouch and 24 daily stools after straight coloanal anastomosis.[30]

Six of our patients developed local recurrence which was much less than seen with other series e.g., 14.6% in study by Localio[26] and 13% in study by Nicholls.[12] The possible explanation is the shorter follow up. Prognosis also seems to be related to TNM stage, histopathology, and surgical procedure.[8921]

It may be pertinent to mention here that our department had admitted and treated only 75 patients of carcinoma rectum from May 2004 to Apr 2007 compared to 117 patients during the next three and half years spanning from May 2007 to December 2010, thus we are seeing an increased number of rectal cancer patients in our hospital.

Conclusion

The concepts of TME, advances in stapling technology and neoadjuvant therapy have made it possible to preserve anal sphincter in most patients, however emphasis should also be laid on preoperative staging, patient selection, procedure type, adherence to surgical oncological principles, and a meticulous follow up. Rectal cancer should be managed in a specialized unit for better results. Improved surgical techniques have improved the results in terms of survival and local recurrence and have brought down the complication rate to an acceptable level. Functional outcome in terms of bowel continence and frequency improves with passage of time and most of the patients do very well after a phase of adaptation even in LARs.