Causes of rectal incontinence after sphincter-preserving operations for rectal cancer

A novel animal model of long-term sustainable anal sphincter dysfunction

BACKGROUND

Although intersphincteric resection can avoid the need for permanent colostomy in patients with lower rectal cancer, it sometimes causes anal sphincter dysfunction, thus resulting in a lifelong, debilitating disorder due to incontinence of solid and liquid stool. The development of regenerative medicine could improve this condition by regenerating impaired anal muscle. In order to prove this hypothesis, preliminary experiments in animals will be indispensable; however, an adequate animal model is currently lacking. The purpose of this study was to establish a novel animal model with long-term sustainable anal sphincter dysfunction.

MATERIALS AND METHODS

Twenty male Sprague-Dawley rats were allocated into sham operation (n = 10) and anal sphincter resection (ASR) (n = 10) groups. The ASR group underwent removal of the left half of both the internal and external anal sphincters. Both groups were evaluated for anal function by measuring their resting pressure before surgery and on postoperative day (POD) 1, 7, 14, and 28.

RESULTS

The rats in the sham operation group recovered their anal pressure up to baseline on POD 7. The rats in the ASR group showed a significant decrease in anal pressure on POD 1 (P < 0.0001) compared with the baseline, and kept this low pressure until POD 28 (P < 0.0001). The defect of the anal sphincter muscle was confirmed histologically in the ASR group on POD 28.

CONCLUSIONS

The present novel model exhibits continuous anal sphincter dysfunction for at least 1 mo and may contribute to further studies evaluating the efficacy of therapies such as regenerative medicine.

Low anterior resection syndrome (LARS): cause and effect and reconstructive considerations

Between 25 and 80% of patients undergoing a low or very low anterior resection will suffer postoperatively, from a constellation of symptoms including fecal urgency, frequent bowel movements, bowel fragmentation and incontinence, collectively referred to as the low anterior resection syndrome (LARS). The etiology of LARS is multifactorial with the potential of sphincter injury during anastomosis construction, alterations in anorectal physiology, the development of a pudendal neuropathy, and a lumbar plexopathy with exacerbation of symptoms if there is associated anastomotic sepsis or the use of adjuvant and neoadjuavnt therapies. The symptoms of LARS may be obviated in part by the construction of a neorectal reservoir which may take the form of a colonic J-pouch, a transverse coloplasty, or a side-to-end anastomosis. This review outlines the factors contributing to LARS symptomatology along with the short- and medium-term functional results of comparative trials with the different types of neorectal reconstructions.

External coloanal anastomosis without covering stoma in low-lying rectal cancer

The aim of this study was to evaluate the safety and functional outcome of external coloanal anastomosis without covering stoma in treating low-lying rectal cancer. All patients undergoing the coloanal anastomosis for low lying rectal carcer in the Department of General Surgery, Minia University Hospital, between May 2006 and May 2009 were included. Seventy two patients underwent coloanal anastomosis, and follow up was available for all patients. Mean follow up period was 12.6 ± 4.7 months. Postoperatively, fecal continence was normal in 84.7% of patients. Postoperative complications included anastomotic fistula in 3 patients (4.2%) and anastomotic stenosis in 6 patients (8.3%). There was no effect of pre or postoperative adjuvant therapy on the procedure outcome. There was no local recurrence during follow up period. Three patients died at the end of follow up period due to distant metastasis. In treatment of low-lying rectal cancer, abdominoperineal resection should be avoided if coloanal anastomosis provides similar control of the disease as it is safe and has good functional results and acceptable complication rate.

Internal anal sphincter parasympathetic-nitrergic and sympathetic-adrenergic innervation: a 3-dimensional morphological and functional analysis

BACKGROUND

Little detailed information is available concerning morphological and functional autonomic nerve supply to the internal anal sphincter. However, denervation of the sphincter potentially affects anal function after rectal surgery for cancer.

OBJECTIVE

The aim of this study was to identify the location and type (nitrergic, adrenergic, and cholinergic) of nerve fibers in the internal anal sphincter and to provide a 3-dimensional representation of their structural relationship in the human fetus.

MATERIALS AND METHODS

serial transverse sections were obtained from 14 human fetuses (7 male, 7 female, 15-31 weeks of gestation) and were studied histologically and immunohistochemically; digitized serial sections were used to construct a 3-dimensional representation of the pelvis.

MAIN OUTCOMES MEASURES

The location and type of internal anal sphincter nerves were assessed qualitatively.

RESULTS

Posteroinferior fibers originating from the inferior hypogastric plexus posteroinferior angle projected to the posterolateral and posterior rectal wall and internal anal sphincter, forming the inferior rectal plexus. The inferior rectal plexus contained vesicular acetylcholine transporter-positive (cholinergic), tyrosine hydroxylase-positive (adrenergic/sympathetic), and neural nitric oxide synthase-positive (nitrergic) fibers. The intrasphincteric vesicular acetylcholine transporter-positive fibers included both neural nitric oxide synthase-negative fibers and neural nitric oxide synthase-positive fibers (nitrergic-parasympathetic).

LIMITATIONS

The study focused on topographic and functional anatomy, so that quantitative data were not obtained. A small number of fetal specimens were available.

CONCLUSIONS

We report the precise location and distribution of the autonomic neural supply to the internal anal sphincter. This description contributes to the understanding of neurogenic postoperative sphincteric dysfunction. Three-dimensional cartography of pelvic-perineal neurotransmitters provides an anatomical and physiological basis for the selection and development of pharmacological agents to be used in the treatment of primary or postoperative continence and evacuation disorders.

Total mesorectal excision with intraoperative assessment of internal anal sphincter innervation provides new insights into neurogenic incontinence

BACKGROUND

The aim of this prospective study was to assess internal anal sphincter (IAS) innervation in patients undergoing total mesorectal excision (TME) by intraoperative neuromonitoring (IONM).

STUDY DESIGN

Fourteen patients underwent TME. IONM was carried out through pelvic splanchnic nerve stimulation under continuous electromyography of the IAS. Anorectal function was assessed with the digital rectal examination scoring system and a standardized questionnaire.

RESULTS

Nine of 11 patients who underwent low anterior resection had positive IONM results, with stimulation-induced increased IAS electromyographic amplitudes (median 0.23 μV (interquartile range [IQR] 0.05, 0.56) vs median 0.89 μV (IQR 0.64, 1.88), p < 0.001) after TME. The patients with the positive IONM results were continent after stoma closure. Of 2 patients with negative IONM results, 1 had fecal incontinence after closure of the defunctioning stoma and received a permanent sigmoidostomy. In the other patient the defunctioning stoma was deemed permanent due to decreased anal sphincter function. In 3 patients who underwent abdominoperineal excision, IONM assessed denervation of the IAS after performance of the abdominal part.

CONCLUSIONS

This study demonstrated that IONM of IAS innervation in rectal cancer patients is feasible and may predict neurogenic fecal incontinence.

Damage to anal sphincter/levator ani muscles caused by operative procedure in anal sphincter-preserving operation for rectal cancer

BACKGROUND

Details of postoperative damage to anal sphincter tonus following sphincter-preserving operation for rectal cancer remain unclear.

METHODS

Postoperative anal tonus was measured using 3-dimensional (3D) vector manometry in 56 patients. Anal length with pressure from any direction was defined as total length (TL). Length with circular pressure (LCP), which is only measurable using 3D manometry, was also evaluated.

RESULTS

In operations associated with low anastomosis, both TL and LCP at rest were significantly shortened when compared with control (high interior resection [HAR]). In particular, degraded LCP at rest was obvious. Anal lengths in squeezing state were preserved except in cases with intersphincteric resection (ISR). Postoperative incontinence score inversely correlated with functional anal length at rest.

CONCLUSIONS

Although the sphincter muscles are mechanically preserved, function of the internal sphincter and subsequent defecatory function can be degraded in cases with operative procedures including surgical maneuvers at the pelvic floor.

Functional outcome following restorative rectal cancer surgery

The trend towards preoperative adjuvant and neoadjuvant therapies in selected patients with rectal cancer has led to increases in sphincter preservation with a limited understanding of the factors governing unsatisfactory functional outcomes. Data would suggest the need for a more selective use of standard radiotherapeutic fields in low- to intermediate-risk cases where there appears to be limited survival or locoregional recurrence benefit and where there is under-reported toxicity. This article discusses the complex factors which impact on functional outcome following open rectal cancer surgery particularly when it is accompanied by adjuvant therapy.

The United Kingdom National Bowel Cancer Project – Epidemiology and surgical risk in the elderly

OBJECTIVE

To evaluate the epidemiology and risk of surgery in the treatment of colorectal cancer in the elderly.

METHODS

Patients undergoing colorectal cancer surgery were identified from the Association of Coloproctology of Great Britain and Ireland (ACPGBI) bowel cancer database, comprising 47,455 patients treated over a 5-year period. Demographic characteristics and outcomes were compared between patients aged <75 and those 75 or above. The primary endpoint was 30-day mortality. Secondary endpoints were the length of hospital stay, abdominoperineal excision (APER) rates and lymph node harvest.

RESULTS

Elderly patients were likely to be female and have higher American Society of Anaesthesiology (ASA) grade, while Dukes' stage was lower. They underwent surgery less often (81% versus 88%, p<0.001), but more frequently needed urgent or emergency procedures (p<0.001) and non-excisional surgery (7.7% versus 6.6%, p<0.001). Operative mortality was significantly higher for the older age group (10.6% versus 3.8%, p<0.001), and their median length-of-stay was 2 days longer (p<0.001). Mortality has improved over time for elderly patients with ASA grade III, and Dukes' stage A and D disease, but not for other subgroups.

CONCLUSION

Significant differences in the demographic characteristics and operative risk-factors between under-75s, and those aged 75 or above exist. These variations are reflected in the inferior outcomes experienced by elderly patients.

The effect of neo-rectal wall properties on functional outcome after colonic J-pouch-anal anastomosis

BACKGROUND/AIMS

It has been suggested that normal function of both anal sphincters is essential for a good functional outcome after colonic J-pouch-anal anastomosis (CPAA). However, CPAA patients may have impaired continence despite adequate sphincter function. The present study was designed to identify those factors, which contribute to the functional outcome after a handsewn CPAA.

MATERIALS AND METHODS

Forty patients were studied before and 1 year after pouch surgery. Faecal continence was evaluated using the Rockwood faecal incontinence severity index (RFISI). At both occasions, maximum anal resting pressure (MARP) and maximum anal squeeze pressure (MASP) were recorded. In addition, sensory perception threshold-volumes (SPT-V) and compliance were assessed using an 'infinitely' compliant polyethylene bag connected to an electronic barostat assembly.

RESULTS

The median RFISI score 1 year after surgery was higher than the median RFISI score before surgery (13 vs 7 (p < 0.01). The median MARP dropped significantly (p < 0.01) whereas the median MASP remained unaffected. The mean compliance, calculated at three different sensation levels, and the pouch sensory perception threshold-volumes (PSPT-V) were lower than those of the original rectum (p < 0.05). The reduction of MARP showed no correlation with the post-operative change in RFISI scores. Low PC and low PSPT-V were associated with higher RFISI scores.

CONCLUSION

Low pouch compliance and low SPT-V adversely affect functional outcome after a handsewn colonic J-pouch-anal anastomosis.

Pudendal Nerve Terminal Motor Latency in Patients With or Without Soiling 5 Years or more after Low Anterior Resection for Lower Rectal Cancer

BACKGROUND

To clarify the neurological function with respect to external anal sphincter (EAS) muscles in patients with or without soiling after low anterior resection (LAR) for lower rectal cancer, we examined the terminal motor latency in the pudendal motor nerves (PNTML).

MATERIALS AND METHODS

Thirty-eight patients after LAR for lower rectal cancer were studied electrophysiologically and compared with 30 healthy volunteers as controls (19 men and 11 women, aged 44 to 76 years of age, with a mean age of 65.5 years). Patients after LAR were divided into two groups [18 patients with soiling (12 men and 6 women, aged 51 to 77 years with a mean age of 64.8 years), 20 patients without soiling (13 men and 7 women, aged 47 to 75 years with a mean age of 62.1 years)]. The mean follow-up time from LAR was 67.2 months (range 60-84 months). Bilateral (left-sided and right-sided) PNTML tests were performed on all patients in order to measure the latency of the response in the bilateral EAS muscle following digitally directed transrectal pudendal nerve stimulation.

RESULTS

The distance from the anal verge to the level of anastomosis in patients with soiling (mean, 2.2 cm) was significantly shorter than that in patients without soiling (mean, 4.1 cm) (P < 0.05). Conduction delay of the bilateral PNTML in patients with soiling was longer than that in patients without soiling and normal subjects, significantly (P < 0.01, respectively). There was no significant difference between the right-sided and left-sided PNTML.

CONCLUSIONS

These findings support the hypothesis that soiling after LAR may be partially caused by damage to the bilateral pudendal motor nerves.

Induction and recovery of colonic motility/defecatory disorders after extrinsic denervation of the colon and rectum in rats

BACKGROUND

Anterior resection for rectal disease is associated with extrinsic autonomic denervation of the neorectum, which may influence the myenteric plexus, and subsequently the motility/defecatory status after operation.

METHODS

A rat model with denervated neorectum was constructed. Colonic contractile activity in vivo, the amount of generic neuron marker (PGP 9.5) and nitric oxide synthase (NOS) were measured periodically. The responses of the muscle strip in each period to electrical field stimulation were evaluated using various neurotransmitters.

RESULTS

In rats with denervated neorectum, giant migrating contractions (GMCs) of the distal colon, the number of fecal lumps per day and their small size, significantly increased in the early phase postoperatively, although both recovered in the late-phase period. The contractile response of the muscle strip of the denervated colon to acetylcholine was reduced throughout the period; however, contraction of the denervated colon under the addition of NO inhibitor (l-NAME) was enhanced significantly in the late-phase period, and recovered to the control level by atropine. Neuronal NOS, but not PGP 9.5 concentration, in the myenteric plexus at the distal denervated colon, significantly increased in the late-phase period. None of the above items differed from the control at other colonic portions throughout the period.

CONCLUSIONS

Extrinsic autonomic denervation causes abnormal hyper-motility in the neorectum, which may be associated with multiple evacuations in the early phase postoperatively. Increased acetylcholine and the subsequent increase of neuronal NOS in the myenteric plexus may be an adaptive mechanism to compensate for such abnormal colonic motility after extrinsic denervation.

Transabdominal anastomosis after low anterior resection: A prospective, randomized, controlled trial comparing long-term results between side-to-end anastomosis and colonic J-pouch

PURPOSE

Colonic J-pouch has been constructed to overcome reservoir dysfunction after restorative rectal surgery, whereas no effort has been made for sphincter dysfunction. We conducted a prospective, randomized study comparing surgical and functional outcomes between side-to-end anastomosis and colonic J-pouch after low anterior resection in which the anastomosis was constructed from the abdomen.

METHODS

Fifty-six consecutive patients with middle-to-low rectal cancer undergoing low anterior resection were randomly assigned to side-to-end or colonic J-pouch group preoperatively. Surgical outcomes of all the patients were recorded. Patients underwent functional evaluation, including anorectal manometry and functional assessment, preoperatively and then 3 months, 6 months, 1 year, and 2 years postoperatively.

RESULTS

Twenty-four patients in each group completed the study. The demographic data and preoperative functional assessment did not differ between the two groups. There was no significant difference in surgical outcomes with regard to anastomotic height (5 cm), blood loss, protective colostomy, operative time, complications, and adjuvant therapy. Anal pressures showed no significant change postoperatively and during the follow-up period; there were no differences between the two groups. Temporal minor fecal incontinence was noted in the early postoperative period in both groups. With regard to bowel function, a significant reduction of volume of urgency and maximal tolerable volume was found postoperatively in both groups; however, a faster recovery was noted in the colonic J-pouch group. Stool frequency increased significantly after surgery in both groups; however, in contrast to rectal volume, a faster recovery was noted in the side-to-end group.

CONCLUSIONS

Anastomosis after low anterior resection for middle to low rectal cancer could be performed safely from the abdomen. It minimized sphincter injury and showed good continence preservation. On the other hand, the surgical outcomes and long-term functional results of side-to-end anastomosis were comparable with colonic J-pouch. Side-to-end anastomosis provides an easier, alternative way for reconstruction after restorative rectal surgery.

Preoperative concurrent radiotherapy with capecitabine before total mesorectal excision in locally advanced rectal cancer

PURPOSE

Capecitabine is an attractive radiosensitizer which can be tumor specific. This study was undertaken to evaluate the toxicity and efficacy of oral capecitabine when used with preoperative radiation therapy.

METHODS AND MATERIALS

We conducted a prospective Phase II trial to assess the pathologic response, sphincter preservation effect, and acute toxicity of preoperative chemoradiation (CRT) in locally advanced (uT3-4/N +) but resectable adenocarcinoma of the lower two-thirds of the rectum. The radiation dose was 50 Gy over 5 weeks (46 Gy to whole pelvis + 4 Gy boost), and capecitabine was administered daily at a dose of 1650 mg/m(2) during the entire course of radiation therapy. Surgery was performed with standardized total mesorectal excision 4 to 6 weeks after completion of CRT and followed by four cycles of capecitabine (2500 mg/m(2)/day for 14 days).

RESULTS

Ninety-five patients were entered into this study; their median age was 55 (range, 31-75 years). Ninety (95%) patients completed preoperative CRT as planned, and complete resection was achieved in 92 of 94 resected cases (98%). Downstaging rate was 71% (56/79) on endorectal ultrasonography, and it was 76% (71/94) on pathology finding. No tumor cell was observed in the specimens of 11 patients (12%). Among the 54 whose tumor was located within 5 cm from the anal verge, 40 patients (74%) underwent sphincter-preserving procedures. Elevation of the distal tumor margin from the anal verge by preoperative CRT was 0.8 +/- 1.3 cm. Grade 3 toxicities were rare (diarrhea in 3% and neutropenia in 1%).

CONCLUSION

Preoperative CRT using capecitabine achieved encouraging rates of tumor downstaging and sphincter preservation with a low toxicity profile.

Sacral nerve stimulation for faecal incontinence following a rectosigmoid resection for colorectal cancer

INTRODUCTION

Following recto-sigmoid resection some patients may become faecally incontinent and remain so despite conservative treatment. This multicentre prospective study assessed the use of sacral nerve stimulation (SNS) in this group.

METHODS

All patients had more than or equal to 4 days of faecal incontinence for solid or liquid stools over a 21-day period following recto-sigmoid resection for colorectal carcinoma. The operation had to have been deemed curative. They had to have failed pharmacological and biofeedback treatment.

RESULTS

Three male patients met these criteria. One had had a colo-anal and two a colo-rectal anastomosis for rectal carcinoma. All patients had intact internal and external anal sphincters. Two patients had a successful temporary stimulation period and proceeded to permanent implantation. Pre-operative symptom duration was 1 year in the permanently implanted patients. They were followed up for 12 months. SNS improved the number of faecally incontinent episodes in both patients. Ability to defer was improved in both patients from 0--5 min to 5--15 min. The faecal incontinence-specific ASCRS quality of life assessment improved in all four subcategories.

CONCLUSION

This study demonstrates that SNS may be effective in the treatment of patients with faecal incontinence following recto-sigmoid resection if conservative treatment has failed.

The management of rectal cancer in the elderly

INTRODUCTION

The majority of patients with rectal cancer are elderly. Due to the increasingly aging population the number of people with colorectal cancer is increasing. As medical advances in the areas of local therapy, radiation therapy, and surgical technique, such as, laparoscopy are made more elderly patients are offered various types of treatment for rectal cancer. As the number of treatment options increase, the debate on how to treat elderly patients' with rectal cancer intensifies.

METHODS

A Medline search using "rectal cancer," "elderly," "local therapy," "radical surgery," and "radiation therapy" as key words was performed for English-language articles. Further references were obtained through cross-referencing the bibliography cited in each work.

DISCUSSION

Numerous treatment options exists for elderly patients with rectal cancer. These range from transanal local excision to radical surgery. The best treatment option for a certain elderly patient is multifactorial and includes tumor stage, operative curability, preoperative functioning of the patient, patient comorbidities, quality of life goals, and patient preference.

CONCLUSION

Age, taken as an independent variable, is not a contraindication to any specific type of therapy, including radical surgery with primary anastomsis. Patients' who meet the criteria for local resection should undergo this procedure. However, for tumors which are not amenable to local resection, these patients should be considered for radical surgery if this provides the best chance for cure. Elderly patients who can tolerate a major operation, and have good preoperative sphincter function should undergo a resection with primary anastomosis.

Denervation of the neorectum as a potential cause of defecatory disorder following low anterior resection for rectal cancer

PURPOSE

The aim of this study was to determine whether denervation of the sigmoid colon during low anterior resection contributes to the postoperative motility characteristics of the neorectum and to the defecatory function of patients.

METHODS

Sixty-seven patients who underwent either low or ultralow anterior resection for rectal cancer were evaluated. In accordance with the length of denervated neorectum, each patient was assigned to either the short-denervation or long-denervation group, determined by whether the inferior mesenteric artery was divided. Colonic propagated contraction was then measured by means of intraluminal pressure monitoring. Transit time was calculated with orally administered radiopaque markers.

RESULTS

Propagated contraction down to the neorectum was significantly less common in the long-denervation group (14/36) than in the short group (12/15, P < 0.05), whereas spastic minor contraction at the neorectum was significantly more common in the long-denervation group (21/36) than the in short group (3/15, P < 0.05). Colonic transit time below the sigmoid colon was significantly longer in long group (6.4 hours) than in the short group (3.4 hours, P < 0.01). Although motility disorder of the neorectum was correlated with clinical defecatory malfunctions, including multiple evacuations, urgency, and soiling, no significant correlation was noted between the length of the denervated neorectum and the defecatory disorders.

CONCLUSIONS

Motility of the neorectum following low anterior resection appears degraded by intraoperative maneuvers that cause denervation of the remnant sigmoid colon. Motility disorder of the neorectum, but not the length of the denervated neorectum causing the disorder, correlates well with several defecatory malfunctions. This finding suggests that postoperative defecatory disorder as a result of low anterior resection is caused by many factors in addition to denervation of the neorectum.

Functional and physiologic assessment of the colonic reservoir or side-to-end anastomosis after low anterior resection for rectal cancer: a two-year follow-up

PURPOSE

Functional disturbances are common after anterior resection for rectal cancer. This study was designed to compare functional and physiologic outcome after low anterior resection and total mesorectal excision with a colonic J-pouch or a side-to-end anastomosis.

METHODS

Functional and physiologic variables were analyzed in patients randomized to a J-pouch (n = 36) or side-to-end anastomosis (n = 35). Postoperative functional outcome was investigated with questionnaires. Anorectal manometry was performed preoperatively and at six months, one year, and two years postoperatively.

RESULTS

There was no statistical difference in functional outcome between groups at two years. Maximum neorectal volume increased in both groups but was approximately 40 percent greater at two years in pouches compared with the side-to-end anastomosis. Anal sphincter pressures volumes were halved postoperatively and did not recover during follow-up of two years. Male gender, low anastomotic level, pelvic sepsis, and the postoperative decrease of sphincter pressures were independent factors for more incontinence symptoms.

CONCLUSIONS

Colonic J-pouch and side-to-end anastomosis gives comparable functional results two years after low anterior resection. Neorectal volume had no detectable influence on function. There was a pronounced and sustained postoperative decrease in sphincter pressures.

Faecal incontinence in adults

Faecal incontinence can affect individuals of all ages and in many cases greatly impairs quality of life, but incontinent patients should not accept their debility as either inevitable or untreatable. Education of the general public and of health-care providers alike is important, because most cases are readily treatable. Many cases of mild incontinence respond to simple medical therapy, whereas patients with more advanced incontinence are best cared for after complete physiological assessment. Recent advances in therapy have led to promising results, even for patients with refractory incontinence. Health-care providers must make every effort to communicate fully with incontinent patients and to help restore their self-esteem, eliminate their self-imposed isolation, and allow them to resume an active and productive lifestyle.

Defecatory malfunction caused by motility disorder of the neorectum after anterior resection for rectal cancer

BACKGROUND

The correlation between postoperative defecatory status after anterior resection for rectal cancer and physiologic neorectal motility has not been well delineated.

METHODS

Sixty patients who underwent anterior resection were examined. Motility of the neorectum was examined with 4-sensor intraluminal pressure monitoring, and segmental colonic transit time was determined with radiopaque Sitzmarks (Konsyl, Fort Worth, Texas) capsules.

RESULTS

Twenty-eight patients experienced loss of propagated contraction waves down to the neorectum, which was closely correlated with a prolonged transit time through the neosigmoid colon and neorectum. In 26 patients, minor spastic waves were observed at the neorectum, which did not correlate well with the loss of propagated waves. The loss of propagation and the existence of spastic waves were significantly correlated with urgency of defecation and multiple evacuations. The latter was also associated with major soiling and with patients' assessments of impaired defecatory function.

CONCLUSIONS

The physiologic motility of the neorectum is one of the factors responsible for postoperative defecatory function after anterior resection for rectal cancer.

Anorectal functional disorders in the absence of anorectal inflammation in patients with Crohn's disease

BACKGROUND

Histological alterations in the enteric nervous system (ENS) have been described in patients suffering from Crohn's disease (CD). The aim of this study was to investigate whether patients with CD without rectal inflammation have abnormal anorectal function compared with healthy volunteers.

METHODS

Fifty-four patients with CD and 26 healthy volunteers were examined by anorectal manometry and answered a standardized questionnaire. No patient had active CD in the rectum as determined by endoscopy.

RESULTS

Maximum anal resting and squeeze pressures did not differ between patients and healthy volunteers. The rectoanal inhibitory reflex was absent in 24 of 54 patients and two of 26 healthy volunteers (P < 0.05). The first sensation to distension of the rectal balloon was reported at mean(s.e.m.) 57.9(4.4) ml by patients and 37.5(2.2) ml by healthy volunteers (P < 0.01). The standardized interview revealed additional disorders of anorectal function in patients with CD.

CONCLUSION

Anorectal function appears to be altered in many patients with CD even in the absence of macroscopic anorectal disease. This may be due to a disorder of the ENS.

Surgeon influenced variables in resectional rectal cancer surgery

PURPOSE

Surgeon influenced variables in rectal cancer surgery were assessed.

METHODS

The literature was reviewed to discuss technical and educational issues that may affect the outcome of surgery for rectal cancer. Particular attention was paid to recently debated topics such as adjuvant therapy, colonic J-pouches, total mesorectal excision, and surgeons' training.

RESULTS

In some selected cases, transanal techniques with or without neoadjuvant or adjuvant therapy have improved the success of local excision. The biology of rectal cancer has begun to be understood. However, until a more complete understanding with an appreciation of therapeutic implications has been arrived at, surgeon influenced variables will continue to be of paramount importance. Multiple studies have shown tremendous surgeon variability in the outcome after rectal cancer surgery. Some of the variables that have been shown to be important include tumor-free distal and lateral margins, a total mesorectal excision, and an appropriate anastomosis. It has been well demonstrated that proctectomy with straight coloanal anastomosis compromises function as compared with preoperative levels or healthy controls. These deficiencies are further exacerbated by adjuvant therapy. Significant functional improvements, particularly in the first 12 to 24 months after surgery, have been achieved with use of colonic J-pouch.

CONCLUSION

There are many ways by which the surgeon can optimize curative resection for rectal cancer. Appropriate distal and tumor-free lateral margins with total mesorectal excision should be the goals for all tumors in the lower two-thirds of the rectum. Reconstruction should be performed, whenever technically possible, by a colonic J-pouch. Surgeons should be cognizant of their own practice patterns, volume, capabilities, and very importantly results. These results should be audited frequently and willingly shared with patients.

Functional outcomes in patients with mucosal ulcerative colitis after ileal pouch-anal anastomosis by the double stapling technique: is there a relation to tissue type?

PURPOSE

The aim of this study was to evaluate any differences in functional outcome in patients with mucosal ulcerative colitis after restorative proctocolectomy and ileal pouch-anal anastomosis with use of the double stapling technique relative to the type of tissue in the stapled doughnut.

METHODS

Between September 1988 and June 1997, the pathology of all patients with mucosal ulcerative colitis who underwent ileal pouch-anal anastomosis with use of the double stapling technique were reviewed. Information was obtained regarding the tissue types in the distal tissue rings (doughnuts) obtained from the stapled ileal pouchanal anastomosis. The level of anastomosis was classified according to the type of tissue in the distal doughnut: Group I- patients in whom the anal transitional zone was removed and the distal doughnut included squamous epithelium or transitional epithelium and Group II- patients in whom the anal transitional zone was preserved because the distal doughnut revealed only columnar epithelium. Functional outcomes were assessed and compared by detailed questionnaires mailed to all patients at least one year after ileal pouch-anal anastomosis surgery.

RESULTS

Distal doughnuts were obtained from the stapled ileal pouch-anal anastomosis in 222 patients with mucosal ulcerative colitis. Follow-up data at a mean of 38 (range, 12-132) months were obtained in 138 (62.2 percent) patients, including 72 males, with a mean age of 46.9 (range, 13-79) years. Group I consisted of 40 patients (29 percent; 35 (25.4 percent) who had squamous epithelium and 5 (3.6 percent) who had transitional epithelium in the distal tissue rings). Group II consisted of 98 patients (71 percent) with columnar epithelium in the distal tissue rings. Age at diagnosis and operation, duration of disease, length of follow-up, and stage of pouch surgery were similar in the two groups. Incontinence scores, frequency of bowel movement, use of a protective pad, discrimination between gas and stool, use of antidiarrheals, life-style alteration, and patient satisfaction showed similar functional results between the two groups.

CONCLUSIONS

The tissue type in the stapler distal doughnut did not greatly influence functional outcome. Failure to identify a relationship may attest to the variable height and composition of the anal transitional zone.

Treatment of colon and rectal cancer

This article discusses multimodal treatment of noncomplicated colon and rectal cancer, considerations for specific types of colon cancer, considerations that may modify the extent and technique of surgery, the role of adjuvant chemotherapy for colon adenocarcinoma and rectal cancer, and surgical treatment of complicated colorectal cancer.

Anorectal dysfunction following low anterior resection for rectal carcinoma: a comparison between handsewn and stapled anastomosis

Sphincter-saving resection for rectal carcinoma is frequently accompanied by anorectal dysfunction (increased stool frequency and varying degrees of faecal incontinence). Although numerous reports regarding this dysfunction have been published, the exact mechanism is still controversial. The purpose of the present study was to compare the functional results of low anterior resection (LAR) for rectal carcinoma following handsewn and stapled anastomosis. The patients with rectal carcinoma were divided into two groups: LAR with handsewn anastomosis (HS) (n = 15), and LAR with stapled EEA (U.S. Surgical Corporation) anastomosis (EEA) (n = 16; four with 28 mm stapler, 12 with 31 mm stapler). Sixteen patients with carcinoma of sigmoid colon who received high anterior resection (HAR) were taken as the control group. Anorectal functional study was performed preoperatively and post-operatively at 1 week and another after 6 months, whereas routine clinical assessment was carried out preoperatively and 6 months post-operatively. The post-operative maximal resting pressure was significantly reduced in both HS and EEA groups, while a tendency to recovery was observed in the HS and 28 mm stapler group 6 months later. A significant decrease in rectal capacity was noted in the EEA group. The return of rectoanal inhibitory reflex was observed in 67% of the HS group and 37.5% of the EEA group. Although clinically increased stool frequency was experienced in both HS and EEA groups, continence was significantly worse in the EEA group. LAR for rectal carcinoma results in impaired anorectal function, which might present clinically with increased stool frequency and minor faecal soiling. The former may be due partially to reduced neorectal capacity, while the latter may be due to internal anal sphincter dysfunction, possibly because of damage to innervation.

Physiological and functional outcome following ultra-low anterior resection with colon pouch-anal anastomosis

BACKGROUND

Low rectal cancer is usually managed by ultra-low anterior resection (ULAR) with total mesorectal excision and straight coloanal anastomosis. However, following this procedure patients often suffer from frequency, urgency of bowel action and, occasionally, faecal incontinence. To overcome such problems, a colon pouch may be fashioned and a subsequent colon pouch-anal anastomosis performed. The physiological and functional outcome following the use of a colon pouch are appraised.

METHODS

All relevant papers identified from a Medline search and papers from cross-referencing were reviewed.

RESULTS AND CONCLUSION

Creation of a colon pouch following ULAR results in reduced bowel frequency, and a lower incidence of urgency and faecal incontinence. Although there is a slightly increased incidence of evacuatory disorder and need for enemas or suppositories, this appears to be a minor problem which may possibly be overcome by using a smaller colon pouch. Compared with straight coloanal anastomosis following ULAR, the creation of a colon pouch produced a superior functional outcome.