Anal Fissure.

Anal fissure (fissure-in-ano) is a very common anorectal condition. The exact etiology of this condition is debated; however, there is a clear association with elevated internal anal sphincter pressures. Though hard bowel movements are implicated in fissure etiology, they are not universally present in patients with anal fissures. Half of all patients with fissures heal with nonoperative management such as high fiber diet, sitz baths, and pharmacological agents. When nonoperative management fails, surgical treatment with lateral internal sphincterotomy has a high success rate. In this chapter, we will review the symptoms, pathophysiology, and management of anal fissures.

Permanent diversion rates after neoadjuvant therapy and coloanal anastomosis for rectal cancer.

BACKGROUND: The aim of this study was to assess the rate of permanent diversion in patients undergoing coloanal anastomosis after neoadjuvant therapy for rectal cancer. METHODS: We performed a retrospective review of patients with rectal cancer who underwent a total mesorectal excision of a tumor within 9 cm of the anal verge. RESULTS: There were 201 patients who underwent resection with coloanal anastomosis, with a mean follow-up period of 51 months. The average tumor distance from the anal verge was 7 cm (range, 4-9 cm). Neoadjuvant therapy was administrated in 145 patients, 47 had no radiation, and 9 received radiation postoperatively. Thirty-two patients (16%) had long-term complications including incontinence, fistulas, and strictures. Twenty-five patients (12%) had recurrent disease, 16 of these were local recurrence. The total rate of permanent diversion was 29 (14%). Reasons for diversion included local recurrence in 12 patients (6%), complications in 10 patients (5%), and poor function in 7 patients (3%). CONCLUSIONS: Poor bowel function, late complications, and local recurrence all contribute to permanent diversion after a coloanal anastomosis. Neoadjuvant therapy in conjunction with a total mesorectal excision and coloanal anastomosis leads to acceptably low permanent diversion rates in the vast majority of patients.

Influence of arginine dietary supplementation on healing colonic anastomosis in the rat.

INTRODUCTION: This study sought to determine whether dietary arginine influences colonic anastomotic healing in the rat model. METHODS: Three groups of 42 Sprague-Dawley rats were fed 0, 1, and 3 percent arginine diets for three preoperative and three postoperative days. Animals underwent transection of the transverse colon with hand-sewn anastomosis. Subgroups of 14 animals in each dietary group were killed on postoperative Days 6, 10, or 14, and bursting pressures, histologic inflammation, and collagen content were compared. RESULTS: Mean anastomotic bursting pressures on postoperative Day 6 were lower for the 0 percent arginine group than the 1 and 3 percent arginine groups (mean +/- standard error of the mean = 134+/-6 mm Hg, 164+/-7 mm Hg, and 166+/-7 mm Hg, respectively; P<0.0005). On Days 10 and 14, no significant differences in bursting pressures were noted between arginine diets. Mean bursting pressures on postoperative Day 6 (155+/-4 mm Hg) were significantly lower than on Days 10 (204+/-5 mm Hg) and 14 (217+/-6 mm Hg; P<0.001) for all arginine diets. Microscopic evaluation of the anastomoses did not show significant differences in inflammation or collagen content between arginine diets. Collagen content in all dietary groups peaked at Day 10. CONCLUSIONS: Perioperative arginine deficiency in the rat model is associated with impaired anastomotic healing during the first week, as reflected by lower bursting pressures. Arginine supplementation to 3 percent does not improve bursting pressures above those found in the usual 1 percent arginine diet at 6, 10, or 14 days. Bursting pressures plateau by Day 10 regardless of perioperative dietary arginine, whereas collagen content peaks at Day 10 after six-day perioperative arginine diet manipulation.

Histologic comparison of hereditary nonpolyposis colorectal cancer associated with MSH2 and MLH1 and colorectal cancer from the general population.

PURPOSE: Hereditary nonpolyposis colorectal cancer is reported to have special histologic features. This study compares the histologic features of hereditary nonpolyposis colorectal cancer to colorectal cancers from the general population when hereditary nonpolyposis colorectal cancer cases are restricted to families with known MSH2 and MLH1 mutations. METHODS: Thirty-seven cancers from kindreds carrying MSH2 mutations, 27 cancers from kindreds carrying MLH1 mutations, and 37 colorectal cancers from the general population were reviewed by a pathologist blinded to hereditary nonpolyposis colorectal cancer gene status. Tumor grade, growth pattern, Crohn's-like lymphoid reaction, mucin production, extent of disease in the bowel wall, and lymph node status were evaluated. RESULTS: Poor differentiation and Crohn's-like reaction were a feature of 44 and 49 percent of hereditary nonpolyposis colorectal cancer compared with 14 percent (P = 0.002) and 27 percent (P = 0.049) of colorectal cancers from the general population, respectively. There was no difference in growth pattern, mucin production, lymph node involvement, or local extent of disease between hereditary nonpolyposis colorectal cancer and colorectal cancers from the general population. Poor differentiation and lymph node metastases were found in 57 and 49 percent of MSH2 compared with 26 percent (P = 0.002) and 10 percent (P = 0.03) of MLH1-associated cancers, respectively. There was no difference in growth pattern, mucin production, Crohn's-like lymphoid reaction, or local extent of disease between subgroups of hereditary nonpolyposis colorectal cancer. CONCLUSIONS: Poor differentiation and Crohn's-like reaction are more common in hereditary nonpolyposis colorectal cancer than colorectal cancers from general population. Poor differentiation and lymph node metastases are more commonly seen in MSH2-associated cancers than MLH1. Evaluation of the natural history, pathogenesis, and prognosis of colorectal cancer in hereditary nonpolyposis colorectal cancer should include consideration of which mismatch repair genes are mutated and what the specific mutations are.

The role of intestinal stoma in patients with spinal cord injury.

In the long term following spinal cord injury, bowel dysfunction causes major physical and psychological problems. A retrospective review of intestinal stomas performed in patients with spinal cord injury over a 10 year period was performed to investigate their role in alleviating these problems. Twelve patients underwent left iliac fossa end colostomy and two patients right iliac fossa end ileostomy. The mean age of patients at operation was 54.8 years (20-65), and the mean time from injury to stoma formation was 15 years (2-37). The mean period of unsatisfactory bowel management before stoma formation was 5.4 years (1.5-2.5). Following colostomy the mean time spent on bowel care per week fell from 8.8 h (0.6-12.2) to 1.4 h (0.3-3.5) and independence in bowel care rose from 50 to 92%. All patients stated that their bowel care was easier and 83% said their independence had increased. Ninety-two per cent wished colostomy had been offered earlier and no patient undergoing colostomy wanted it reversed. The most common complication following colostomy was exclusion colitis. The mean time of follow-up post colostomy formation was 38 months (7-130). Formation of an intestinal stoma is a safe, effective and well accepted treatment for selected patients with intractable problems of bowel management following spinal cord injury.

Cumulative incidence of colorectal and extracolonic cancers in MLH1 and MSH2 mutation carriers of hereditary nonpolyposis colorectal cancer.

The extracolonic tumor spectrum of hereditary nonpolyposis colorectal cancer (HNPCC) includes cancer of the endometrium, ovaries, stomach, biliary tract, and urinary tract. This study was designed to determine the penetrance of colorectal and extracolonic tumors in HNPCC mutation carriers. Forty-nine patients (22 females and 27 males) were identified with an MSH2 germline mutation, and 56 patients (28 females and 28 males) were identified with an MLH1 I mutation. Cumulative incidence by age 60 (lifetime risk) and mean age of cancer diagnosis were compared. The lifetime risk of extracolonic cancers in MSH2 and MLH1 carriers was 48% and 11%, respectively (P = 0.016). Extracolonic cancer risk in MSH2 females and males was 69% and 34%, respectively (P = 0.042). Mean age of extracolonic cancer diagnosis was significantly older for MSH2 males than females (55.4 vs. 39.0, P = 0.013). No difference was observed in colorectal cancer risk between MLH1 and MSH2 carriers (84% vs. 71%). Colorectal cancer risk was 96% in MSH2 males compared to 39% in MSH2 females (P = 0.034). No differences in colorectal and extracolonic cancer risks between MLH1 females and males were identified. The risk of extracolonic cancer by age 60 was greater in MSH2 mutation carriers than in MLH1 carriers. Gender differences in colorectal and extracolonic cancer risk were observed for MSH2 carriers only. These phenotypic features of HNPCC genotypes may have clinical significance in the design of genotype-specific screening, surveillance, and follow-up for affected individuals.

Colorectal carcinoma survival among hereditary nonpolyposis colorectal carcinoma family members.

BACKGROUND: Patients with hereditary nonpolyposis colorectal carcinoma (HNPCC) reportedly have better prognoses than sporadic colorectal carcinoma (CRC) patients, but it has been unclear whether this could be due to differences in stage at diagnosis. The current study compared stage and survival in a retrospective cohort of HNPCC family members who developed CRC with the same factors in an unselected hospital series of patients with sporadic CRC. METHODS: This retrospective cohort study compared HNPCC cases (274 cases from 98 HNPCC families) with an unselected hospital series comprising 820 consecutive CRC cases. All patients were staged according to the TNM system of the American Joint Committee on Cancer and the International Union Against Cancer. Median follow-up among living patients was > 10 years and 8.5 years, respectively, for the two cohorts. Cox regression was used to compare survival in stage-stratified analyses of time from diagnosis to death. RESULTS: Compared with the unselected series, the HNPCC cases had lower stage disease (P < 0.001), and fewer had distant metastases at diagnosis (P < 0.001 in an analysis stratified by T classification). In stage-stratified survival analysis, the HNPCC cases had a significant overall survival advantage regardless of adjustment for their younger age. A conservative estimate of the hazard ratio (of HNPCC cases to the unselected series) was 0.67 (P < 0.0012). CONCLUSIONS: HNPCC patients had lower stage disease at diagnosis than the unselected CRC cases, mainly due to rarer distant metastases at diagnosis. They survived longer than unselected CRC patients with tumors of the same stage. The estimated death rate for the HNPCC cases, adjusted for stage and age differences, was at most two-thirds of the rate for the hospital series.

Colorectal and extracolonic cancer variations in MLH1/MSH2 hereditary nonpolyposis colorectal cancer kindreds and the general population.

PURPOSE: This clinical case review aimed to identify phenotypic variations in colorectal and extracolonic cancer expression between hereditary nonpolyposis colorectal cancer (HNPCC) families with MLH1 and MSH2 germline mutations and the general population. METHODS: Colorectal cancer onset and site distribution were compared among 67 members of MLH1 kindreds, 45 members of MSH2 kindreds, and 1,189 patients from the general population. Synchronous and metachronous cancer rates, tumor stage, extracolonic cancer incidence, and survival were also compared. RESULTS: Mean ages of colorectal cancer onset were 44, 46, and 69 years for MLH1, MSH2, and the general population, respectively (P < 0.001). More proximal and fewer distal colon cancers were noted in HNPCC than the general population (P < 0.001, P = 0.04). Site distribution showed disparity of rectal cancers (8 percent MLH1 vs. 28 percent MSH2; P = 0.01) based on genotypes. Overall, synchronous colorectal cancer rates were 7.4, 6.7, and 2.4 percent for MLH1, MSH2, and the general population, respectively (P = 0.016). Annual metachronous colorectal cancer rates were 2.1, 1.7, and 0.33 percent for MLH1, MSH2, and the general population, respectively (P = 0.041). Colorectal cancer stage presentation was lower in HNPCC than the general population (P = 0.0028). Extracolonic cancers were noted in 33 percent of MSH2 patients, compared with 12 percent of MLH1 patients and 7.3 percent of the general population with colorectal cancers (P < 0.001). Combined MLH1 and MSH2 ten-year survival was 68.7 percent compared with 47.8 percent for the general population (P = 0.009 stage stratified, hazard ratio 0.57). CONCLUSION: The presence of rectal cancer should not preclude the diagnosis of HNPCC, because the incidence of rectal cancer in MSH2 was comparable with that in the general population. Phenotypic variations, including the preponderance of extracolonic cancers in MSH2 patients, did not result in survival differences between genotypic subgroups. These phenotypic features of HNPCC genotypes may have clinical significance in the design of specific screening, surveillance, and follow-up for affected individuals.

Transanal ultrasound and anorectal physiology findings affecting continence after sphincteroplasty.

PURPOSE: This study was undertaken to evaluate endosonographic and physiologic determinants of fecal continence after sphincteroplasty. METHODS: Sixteen female patients with severe fecal incontinence were treated with overlapping sphincteroplasty. Mean postoperative follow-up was 12 (range, 3-48) months. All patients underwent preoperative and postoperative transanal endosonography and anal manometry. Bilateral pudendal nerve terminal motor latency determinations were performed in each patient. A physiologic continence score was used to assess stool control. RESULTS: Postoperatively, continence was worse, unchanged, and improved in one, five, and ten patients, respectively. An inverse correlation was noted between endosonographic sphincter discontinuity postoperatively, in degrees, and the change in fecal continence after overlapping sphincteroplasty (r = -0.51; P = 0.04). Postoperative increases in sphincter resting (r = 0.6; P = 0.02) and squeeze (r = 0.54; P = 0.03) pressures correlated with improved fecal continence. Mean pudendal nerve terminal motor latency (r = -0.34; P = 0.20) and changes in anal sphincter length at rest (r = 0.41; P = 0.11) and squeeze (r = 0.33; P = 0.20) after sphincteroplasty did not significantly correlate with the change in continence. Patients with intact endosonographic anatomy postoperatively and bilateral, unilateral, or no evidence of pudendal neuropathy had a mean change in continence score of 0.5, 1.8, and 2.2, respectively (P = 0.48). CONCLUSIONS: Endosonography after sphincteroplasty can identify residual sphincter defects that are significant in terms of fecal continence. Restoration of anal canal resting and squeeze pressures was related to improved fecal control after overlapping sphincteroplasty. Mean pudendal nerve terminal motor latency was not significantly related to poor postoperative continence. A trend toward less improvement in fecal continence was noted with bilateral pudendal neuropathy.