Molecular markers and prediction of response to chemoradiation in rectal cancer.

Preoperative chemotherapy and radiation (chemoradiation) are increasingly used in the treatment of advanced rectal carcinoma to downstage the tumor so that a sphincter sparing procedure is used. This treatment modality has also resulted in not only local disease control but also decreased metastasis and increased survival. It is well known that with standard chemoradiation some tumors show marked pathologic response, while others remain non-responsive. Identification of tumor markers that can predict responsiveness to chemoradiation is extremely useful to avoid unnecessary preoperative treatment. To understand the role of thymidylate synthase (TS), p53 and Bcl-2 proteins, if any, in tumor response/resistance to chemoradiation, we examined pretreatment biopsy material obtained from 12 responsive and 13 non-responsive patients by immunohistochemistry. TS was undetectable in 11 of 12 (92%) responsive tumors and overexpressed in only 1 tumor (8%); whereas, p53 or Bcl-2 was overexpressed in 8 tumors (66%). In the non-responsive group of 13 tumors, overexpression of TS, p53 and Bcl-2 was observed in 7, 5 and 6 tumors, respectively. In 6 non-responsive tumors in which TS was undetectable, 5 tumors contained high levels of p53 or Bcl-2. These results indicate that level of TS in tumors is the best predictor of sensitivity or resistance to chemoradiation. No such correlation between overexpression of p53 and Bcl-2 and response to chemoradiation is observed.

Total antioxidant capacity of colon in patients with chronic ulcerative colitis.

It has been proposed that oxidative stress is involved in the pathophysiology of ulcerative colitis. We have reported the depletion of the nonenzymatic antioxidant, glutathione, in colon from active and inactive ulcerative colitis. The colon contains several biochemically linked antioxidant systems. We hypothesized that diminished total antioxidant capacity in active ulcerative colitis would be associated with increased colonic lipid peroxidation. This study was designed to determine total antioxidant capacity and lipid hydroperoxide levels using colon obtained at surgery from controls (N = 16; 4 females, 12 males; mean age 70 years), and active and inactive ulcerative colitis (N = 15; 3 females, 12 males; mean age 39). Total antioxidant capacity of control colon was higher in muscularis externa compared to the mucosal-submucosal layer (P < 0.05). There were no differences in colonic total antioxidant capacity or lipid hydroperoxide levels comparing control colon to inactive and active ulcerative colitis. The results did not support depletion of tissue total antioxidant capacity by free radicals. Depletion of glutathione in ulcerative colitis may be a specific disorder rather than a secondary defect attributable to global oxidative stress. Nonspecific antioxidant supplements appear unlikely to be beneficial in the treatment of ulcerative colitis.

The learning curve for laparoscopic colorectal surgery. Preliminary results from a prospective analysis of 1194 laparoscopic-assisted colectomies.

BACKGROUND: Laparoscopic-assisted colectomy is an emerging technology for patients with cancer, polyps, inflammation, and other types of pathologic conditions. While previous studies have shown better outcomes for laparoscopic cholecystectomies when surgeons perform more procedures, there is no information on the relationship between surgeon volume and outcomes for laparoscopic-assisted colectomy. OBJECTIVE: To evaluate whether better clinical outcomes are found for surgeons who perform higher numbers of laparoscopic-assisted colectomies and whether such a relationship, if it exists, applies to both intraoperative and postoperative outcomes. DESIGN: Analysis of a data set of 1194 patients, operated on by 114 surgeons, from a prospective registry sponsored by the American Society of Colon and Rectal Surgeons, from May 1991 to October 1994. MAIN OUTCOME MEASURES: Completion rate, intraoperative and postoperative complications, and length of hospital stay. RESULTS: In 75% of cases, surgery was completed laparoscopically, with no difference between high-volume surgeons (> or = 40 cases) and low-volume surgeons. Length of stay (average, 6 days) did not vary according to surgeon volume. Postoperative complications occurred in 15% of cases, with a significantly lower rate for high-volume surgeons (10% vs 19%; P < .001). Intraoperative complications occurred in 5% of cases, with a nonsignificant trend toward a lower rate for high-volume surgeons (3.7% vs 6.3%). A multivariate regression analysis, adjusting for type of disease (cancer vs inflammation vs polyps) and for level of difficulty of the procedure (high vs low) showed that for high-volume surgeons there is a lower probability of both intraoperative complications (adjusted odds ratio, 0.56; 95% confidence interval, 0.32-0.97; P = .04) and postoperative complications (adjusted odds ratio, 0.48; 95% confidence interval, 0.34-0.68; P < .001). CONCLUSIONS: There is a learning curve for laparoscopic-assisted colectomy with respect to intraoperative and postoperative outcomes. As with other laparoscopic procedures, surgeons who perform higher volumes of laparoscopic-assisted colectomy have lower rates of intraoperative and postoperative complications.

Prevention of postoperative abdominal adhesions by a sodium hyaluronate-based bioresorbable membrane: a prospective, randomized, double-blind multicenter study.

BACKGROUND: Postoperative abdominal adhesions are associated with numerous complications, including small bowel obstruction, difficult and dangerous reoperations, and infertility. A sodium hyaluronate and carboxymethylcellulose bioresorbable membrane (HA membrane) was developed to reduce formation of postoperative adhesions. The objectives of our prospective study were to assess the incidence of adhesions that recurred after a standardized major abdominal operation using direct laparoscopic peritoneal imaging and to determine the safety and effectiveness of HA membrane in preventing postoperative adhesions. STUDY DESIGN: Eleven centers enrolled 183 patients with ulcerative colitis or familial polyposis who were scheduled for colectomy and ileal pouch-anal anastomosis with diverting-loop ileostomy. Before abdominal closure, patients were randomly assigned to receive or not receive HA membrane placed under the midline incision. At ileostomy closure eight to 12 weeks later, laparoscopy was used to evaluate the incidence, extent, and severity of adhesion formation to the midline incision. RESULTS: Data were analyzed for 175 assessable patients. While only five (6 percent) of 90 control patients had no adhesions, 43 (51 percent) of 85 patients receiving HA membrane were free of adhesions (p < 0.00000000001). The mean percent of the incision length involved was 63 percent in the control group, significantly greater than the 23 percent observed in patients who received HA membrane (p < 0.001). Dense adhesions were observed in 52 (58 percent) of the 90 control patients, but in only 13 (15 percent) of the 85 receiving HA membrane (P < 0.0001). Comparison of the incidence of specific adverse events between the groups did not identify a difference (P > 0.05). CONCLUSIONS: This study represents the first controlled, prospective evaluation of postoperative abdominal adhesion formation and prevention after general abdominal surgery using standardized, direct peritoneal visualization. In this study, HA membrane was safe and significantly reduced the incidence, extent, and severity of postoperative abdominal adhesions.

Decreased vasoactive intestinal peptide levels and glutathione depletion in acquired megacolon.

We reported decreased vasoactive intestinal peptide levels in acquired megacolon. The origin of altered neuropeptide levels is unknown, but recent work suggested that tissue antioxidants may function as neuroprotectants. Our hypothesis was that altered levels of inhibitory neurotransmitters in human colon are associated with depletion of the tripeptide thiol, glutathione. Normal colon samples (N = 10; from patients 41-80 years old) and acquired megacolon samples (N = 10; from patients 31-98 years old) were obtained at surgery. Vasoactive intestinal peptide levels were decreased in muscularis externa from acquired megacolon (P = 0.01), while there was a modest increase in NADPH diaphorase activity in muscularis externa from megacolon (P = 0.10). Glutathione in acquired megacolon was detectable in muscularis externa from only five specimens (P < 0.05), but was not significantly different (P > 0.05) in the mucosal-submucosal layer. The results supported the presence of vasoactive intestinal peptide and NADPH diaphorase in distinct subpopulations of nerves in human colon. The results also supported the hypothesis that glutathione functions as a neuroprotectant in a subset of patients with acquired megacolon.

Preoperative "chemoradiation" for stages II and III rectal carcinoma.

OBJECTIVE: To determine whether preoperative administration of combination chemotherapy and external beam irradiation ("chemoradiation") for patients with stage II or stage III rectal carcinoma had an impact on perioperative morbidity on oncologic outcome, as compared with patients not receiving preoperative chemoradiation. DESIGN: A group of patients with stage II or stage III rectal carcinoma receiving preoperative chemoradiation were followed up prospectively and compared in a nonrandomized fashion with an inception cohort group of similar patients. SETTING: Northwestern Memorial Hospital, Chicago, Ill, a tertiary care academic medical center. PATIENTS: Thirty patients with rectal carcinoma undergoing preoperative chemoradiation were compared with 56 patients not undergoing preoperative chemoradiation, and also with a subset group of 24 patients who received standard postoperative adjuvant chemoradiation. INTERVENTION: External beam radiation, 45 to 50 Gy, was delivered concurrently with fluorouracil and mitomycin 4 to 8 weeks prior to surgical resection. MAIN OUTCOME MEASURES: Patients were followed up at regular intervals for either tumor recurrence or death. In addition, the group receiving preoperative chemoradiation was evaluated for major preoperative morbidity. RESULTS: All patients agreeing to preoperative chemoradiation completed therapy. Perioperative major morbidity in this group (13%) was comparable to previously published results. Of the 56 patients with stage II or stage III rectal carcinoma not receiving preoperative chemoradiation, only 24 (43%) completed standard postoperative adjuvant chemoradiation. Patients receiving preoperative chemoradiation (n = 30), patients not receiving preoperative chemoradiation (n = 56), and the subset of the group not receiving preoperative chemoradiation who completed standard postoperative chemoradiation (n = 24) were followed up for a mean of 39 months, 31 months, and 32 months, respectively. Five-year actuarial local control rates were 96%, 83%, and 88%, respectively. Disease-free-survival rates were 80%, 57%, and 47%, respectively. Overall survival rates were 85%, 48%, and 78%, respectively. CONCLUSIONS: Preoperative chemoradiation in the treatment of stage II or stage III rectal carcinoma is well tolerated and not associated with an increase in subsequent perioperative major morbidity. In addition, local control, disease-free survival, and overall survival compare favorably with a nonrandomized inception cohort group of patients receiving standard postoperative adjuvant chemoradiation.

p53 Protein overexpression in colorectal tumors from patients with familial adenomatous polyposis: is it an early or late event?

OBJECTIVES: Tumor development is a multistep process associated with multiple genetic alterations. Familial adenomatous polyposis (FAP) is a classical paradigm to study genetic alterations in the development of colorectal neoplasms. In this study, we investigated the timing of p53 overexpression by immunohistochemistry in colorectal carcinogenesis in FAP patients and in sporadic adenomas and adenocarcinomas. METHODS: We examined 40 microadenomas, 114 tubular adenomas, and three adenocarcinomas from five FAP patients and 30 sporadic adenomas and 14 sporadic adenocarcinomas. RESULTS: p53 overexpression was observed in 43 of 114 adenomas with mild and moderate dysplasia and in three of three adenocarcinomas and in none of 40 microadenomas from FAP patients. In sporadic tumors, six of 30 adenomas with moderate to severe dysplasia and 11 of 14 carcinomas showed p53 overexpression. Uninvolved colonic mucosa in FAP patients, control patients, and patients with sporadic tumors did not stain for p53. CONCLUSIONS: These results indicate that p53 overexpression occurs early in the development of colorectal adenomas in FAP, whereas it is a late event in the development of sporadic tumors.

Inflammatory pseudotumor of the pancreas.

We describe a rare example of inflammatory pseudotumor of the pancreas in a 42-yr-old woman, which developed following chemotherapy for lymphoma of the uterine cervix. The patient had developed fatigue, weight loss, abdominal pain, and anemia; abdominal CT scan showed a large mass in the pancreas. Examination of the resected specimen revealed a fleshy, well-circumscribed, 7-cm mass. Histologically, there was a hypocellular to moderately hypercellular, bland spindle-cell proliferation admixed with a prominent infiltrate of lymphocytes, histiocytes, and plasma cells. The spindle cells were vimentin positive but negative for muscle markers; electron microscopy revealed only fibroblastic cells. DNA analysis revealed a diploid population with low S-phase fraction. The patient was well at 6-mo follow-up. It is important for the pathologist to be aware of the existence of this entity in unusual locations such as the pancreas so as to avoid a mistaken diagnosis of malignancy.

Appendiceal involvement as a skip lesion in ulcerative colitis.

Despite the frequency of ulcerative colitis (UC), and numerous studies related to this disease, controversy remains regarding its distribution patterns. It is generally believed that UC starts in the rectum and progresses proximally in continuity to involve cecum along with appendix in 50% of all cases. However, recent endoscopic and histological studies suggest that UC can occur as a discontinuous process. Furthermore, the few existing studies specifically addressing appendiceal histology in UC are divided over whether ulcerative appendicitis (UA) may be seen without cecal involvement (i.e., as a "skip lesion"). To study the appendiceal pathology in UC, and in particular the frequency of UA as a "skip lesion," we retrospectively evaluated 39 proctocolectomy specimens containing appendices removed for UC. Six cases (17%) had obliterated appendices; appendiceal and cecal histologies of the remaining 33 cases were divided into (a) active disease, (b) quiescent disease, or (c) nonspecific or normal histology. Twenty of 39 appendices (51%) showed active disease, four (10%) had quiescent disease, and nine (23%) were either normal or nonspecifically inflamed. After exclusion of one case for inadequate cecal sampling, comparison of cecal and appendiceal histologies showed concordance in 16 cases and discordance in the remaining 16. Of these discordant cases, six had greater disease activity in the cecum and 10 had greater activity in the appendix. Of these latter 10 cases, six showed normal or nonspecific cecal histology associated with active UA. Thus, "skip lesions" of the appendix were detected in 15% of the UC specimens examined.

Acquired megacolon is associated with alteration of vasoactive intestinal peptide levels and acetylcholinesterase activity.

Based upon previous morphologic studies, we hypothesized that the development of acquired megacolon was associated with abnormalities of enteric neurotransmitter concentrations and enzymatic activities. Specimens were obtained at surgery from patients with normal descending-sigmoid colon (n = 13) and patients with sigmoid megacolon (n = 6; defined by radiologic measurement). Radioimmunoassays were used to measure the non-adrenergic, non-cholinergic inhibitory neuropeptide, vasoactive intestinal peptide, and the non-adrenergic, non-cholinergic excitatory neuropeptide, substance P, while spectrophotometric assays were used to quantitate acetylcholinesterase activity and choline acetyltransferase activity. There were significantly decreased concentrations of vasoactive intestinal peptide and decreased acetylcholinesterase activity in muscularis externa from patients with acquired megacolon. In megacolon, vasoactive intestinal peptide-containing nerve fibers appeared to be diminished in circular and longitudinal smooth muscle, and immunostaining of nerve cell bodies in the plexus submucosus externus appeared diminished. These results suggest the hypothesis that production of vasoactive intestinal peptide is altered allowing secondary colonic hypertrophy to develop from prolonged cholinergic nerve-mediated contractions of circular smooth muscle. As a corollary to this hypothesis, colonic dilatation might result from prolonged contraction of longitudinal smooth muscle.

A comparison of general versus local anesthesia during inguinal herniorrhaphy.

The current study was done to compare the hemodynamic changes, recovery events and economic impact of elective inguinal herniorrhaphy performed with general anesthesia (GA) or regional field block (RB) in 20 patients (American Society of Anesthesiology class I). In the GA group, anesthesia was induced with thiopental and the trachea was intubated after intravenous administration of 0.08 milligrams per kilogram of vecuronium. GA was maintained with 1.2 +/- 0.25 per cent enflurane in 50 per cent nitrous oxide and oxygen, and ventilation was controlled to keep PECO2 at 36 +/- 2 millimeters of mercury. Anesthesia in the RB group was accomplished by local injection of 3.5 +/- 0.5 milligrams per kilogram of 0.5 per cent bupivacaine. In each patient, a suprasternal ultrasonic Doppler probe was used to measure cardiac output before induction of anesthesia, during and after operation. Total peripheral resistance was calculated from mean arterial pressure and cardiac output. There were no statistically significant differences between cardiac output, mean arterial pressure, total peripheral resistance and heart rate in the two groups at any time period during the study. Patients in the RB group did not require parenteral medication for relief of postoperative pain, whereas all those in the GA group did. Significant cost benefits were realized by the RB group because of elimination of general anesthetic and reduction of recovery room fees.

Gastrointestinal endometriosis. Incidence and indications for resection.

Of 1573 consecutive patients with endometriosis diagnosed at laparoscopy or celiotomy, 85 patients (5.4%) had gastrointestinal involvement and 11 patients (0.7%) required bowel resection due to recurrent gastrointestinal symptoms (usually obstructive in nature) and/or suspicion of malignancy. Of 63 patients with gastrointestinal involvement at sites other than the appendix, who did not undergo bowel resection, only two patients had gastrointestinal symptoms at the time of diagnosis (neither patient had obstructive symptoms); follow-up has revealed that only one patient subsequently developed significant gastrointestinal symptoms. Fifteen patients had appendiceal endometriosis, but none had symptoms suggestive of appendicitis. Indications for resection of gastrointestinal endometriosis include the presence of clear-cut obstructive symptoms or the inability to exclude malignancy. The absence of gastrointestinal symptoms appears to be predictive of the absence of clinically significant intestinal endometriosis, and bowel resection is not indicated in the asymptomatic patient. Appendiceal endometriosis appears to be an incidental finding and one that is not clinically important.

Anal canal pressure and motility after ileoanal anastomosis.

This study was done to determine the effect of mucosal rectectomy and ileal pouch to anal anastomosis (IAA) on pressure and motility of the anal canal. Fifty patients, 22 +/- 2 months after operation (mean plus or minus standard error of the mean), and 30 healthy control volunteers were studied. Twenty-eight patients had excellent continence, while 22 had episodic minor incontinence. The maximum resting pressure in the anal canal was reduced in patients with episodic incontinence compared with continent patients and control volunteers. The increase in pressure with squeeze was slightly greater in continent than in incontinent patients. The frequency of the anal slow waves was less after IAA than in control volunteers and the amplitude of the waves was greater. The frequency and amplitude, however, were not related to continence or resting pressure. In conclusion, decreased anal canal resting and squeeze pressures after ileal pouch to anal anastomosis are associated with episodic minor incontinence, while altered motility patterns in the anal canal are not.

Natural history of untreated colonic polyps.

The natural history of untreated colonic polyps is uncertain. A retrospective review of Mayo Clinic records from a 6-yr period just before the advent of colonoscopy identified 226 patients with colonic polyps greater than or equal to 10 mm in diameter in whom periodic radiographic examination of the colon was elected over excisional therapy. In all patients, follow-up of polyps spanned at least 12 mo (mean, 68 mo; range, 12-229 mo) and included at least two barium enema examinations (mean, 5.2; range, 2-17). During the follow-up period, 83 polyps (37%) enlarged. Twenty-one invasive carcinomas were identified at the site of the index polyp at a mean follow-up of 108 mo (range, 24-225 mo). Actuarial analysis revealed that the cumulative risk of diagnosis of cancer at the polyp site at 5, 10, and 20 yr was 2.5%, 8%, and 24%, respectively. In addition, 11 invasive cancers were found at a site remote from the index polyp during the same follow-up period. These data further support the recommendation for excision of all colonic polyps greater than or equal to 10 mm in diameter. Periodic examination of the entire colon is recommended in this group of patients to identify neoplasms arising at a site remote from the index polyp. Although this study has limitations inherent to any retrospective analysis, comparable prospective data are unlikely to be available in the future because of the current widespread availability of colonoscopy.

Multiple adenomatous polyps arising in a continent reservoir ileostomy.

In a 29-year-old man who presented with leakage from a continent ileostomy after proctocolectomy, endoscopic evaluation of the reservoir revealed extensive adenomatous polyposis. The polyps were not present at the time of revision of the reservoir 4 years earlier. Because it was not possible to fashion an adequate nipple valve in the presence of so many polyps and the concern over possible malignant transformation, the reservoir was excised. This is the second reported case of polyposis involving a continent reservoir ileostomy. Patients with a continent ileostomy constructed after proctocolectomy for polyposis coli should be evaluated endoscopically at regular intervals.

Anal and neorectal function after ileal pouch-anal anastomosis.

Bowel function varies markedly among patients with colectomy and ileal pouch-anal anastomosis. Little is known of the mechanisms controlling fecal continence and frequency of defecation after operation. The aim of this study was to determine which features of the anal sphincter and neorectum accounted for the variation in clinical outcome. Twenty patients were studied 4 to 35 months after operation and compared to 12 healthy volunteers. Despite several patients exhibiting impaired fecal continence, anal sphincteric length and pressures and ileal pouch capacity and distensibility were similar in patients and controls. Patients with poor results, however, had rapid filling of their ileal pouch, which resulted in early onset of high amplitude propulsive pressure waves in the pouch. As these waves became more frequent, defecation resulted. Patients with poor results also were not able to empty adequately their pouch. The poorer the completeness of evacuation, the more frequent the defecation (r = 0.62, p less than 0.01). The authors conclude that rapid pouch filling and impaired pouch evacuation can lead to increased stool frequency in patients after ileal pouch-anal anastomosis.

Anoneorectal evaluation after colectomy and endorectal ileoanal anastomosis in children and young adults.

Recent improvements in the technique of colectomy, rectal mucosectomy, and endorectal ileoanal anastomosis allow a satisfactory result in most patients. However, the clinical outcome is not entirely satisfactory in about 5% to 10% of patients because of excessive stool frequency or episodic fecal incontinence or both. We evaluated anoneorectal function postoperatively to help explain the mechanisms of the difficulties. Six patients with imperfect functional results (group 1) and 6 with good functional results (group 2) after ileoanal anastomosis and closure of the loop ileostomy were compared with 12 healthy volunteers who had not had operation, through a series of tests designed to evaluate anal sphincter and neorectal function. All patients were instructed in balloon dilation of the neorectum to develop a reservoir while awaiting closure of the ileostomy. Anal sphincter manometric measurements of resting and squeeze pressures were obtained with a 4-channel probe attached to a noncompliant pneumohydraulic perfusion system. Incremental inflation of an intraluminal bag while pressures were simultaneously recorded allowed determinations of neorectal capacity and distensibility. The efficiency of neorectal evacuation was assessed by instilling a labeled synthetic viscous load into the distal bowel. Patients in group 1 had lower resting anal pressures (P less than 0.05), lower squeeze pressures (P less than 0.05), smaller neorectal capacities (P = 0.13), and less neorectal distensibility (P = 0.27) than patients in group 2. Furthermore, the values for patients in group 2 closely approximated those found in healthy volunteers.(ABSTRACT TRUNCATED AT 250 WORDS)

Long-term results of ileostomy in older patients.

Surgical alternatives to proctocolectomy and ileostomy appear to be associated with poor functional results in older patients. Surprisingly, little has been written regarding the long-term results of conventional ileostomy in the elderly. Questionnaires were sent to all patients requiring ileostomy between 1966 and 1980. Six hundred seventy-five patients responded (81 percent). Sixty-seven (10 percent) of the respondents were 60 years of age or older at the time of surgery. In all categories dealing with quality of life assessment, the group of older patients fared as well or better than those younger than age 60. Older patients, however, reported greater difficulty in daily management of their stomas (P less than 0.01). Patients 60 years of age or older tolerate ileostomy well, but care of the stoma can cause problems. Occupational and activity restrictions, however, are no more prevalent in older patients than in their younger counterparts.

Anal sphincter electromyography after colectomy, mucosal rectectomy, and ileoanal anastomosis.

Electromyography (EMG) was used to evaluate the external anal sphincter in 27 patients following colectomy, distal mucosal rectectomy, and ileoanal anastomosis. The studies were conducted four months to 58 months (mean, 20 months) following the restoration of intestinal continuity. Nine patients underwent endoanal rectal mucosal stripping, while in 18 patients the rectum was everted to facilitate the stripping. Postoperative continence varied widely, from perfect to frequent and severe mucous of fecal leak. Abnormal motor-unit potentials were identified by EMG in nine patients and this finding was usually associated with poor continence. The sex of the patient, technique of mucosal stripping, and type of anastomosis did not influence the EMG result, but patients at least 40 years old all had abnormal EMGs. We conclude that poor continence after ileoanal anastomosis correlates with an abnormal EMG of the external anal sphincter. The cause of the EMG abnormality is unclear.

Motility of the small intestine after proctocolectomy and ileal pouch-anal anastomosis.

Though the mechanisms of continence after proctocolectomy and ileal pouch-anal anastomosis have been studied, functions of the small intestine have received little attention. However, frequent stools and urgency plague some patients who are otherwise quite continent. Motility of the jejunum and ileum was assessed in eight patients with ulcerative colitis who were studied 4 to 24 months after proctocolectomy and ileal pouch-anal anastomosis; these findings were compared to those in six healthy volunteers. Continuous manometric recordings from the small bowel were obtained in both groups for 16 to 23 hours of fasting; postprandial recordings were made for 6 hours following a mixed meal (800 kcal, 20% protein, 40% fat, 40% carbohydrate) in the ileoanal patients. The duration, velocity of propagation, and periodicity of the migrating motor complex did not differ between the groups (P greater than 0.05). Discrete bursts of clustered contractions were recorded from all of the controls and in five of eight patients. Likewise, we recorded from all controls and five of eight patients large amplitude, prolonged waves of pressure which propagated distally. However, in controls these large amplitude waves were confined to the terminal ileum, but in patients these were detected in the jejunoileum, up to 125 cm proximal to the ileal pouch. We conclude that jejunoileal motility is not greatly altered by proctocolectomy with ileal pouch-anal anastomosis. However, the appearance of the large amplitude, rapidly propagating waves in the proximal jejunoileum after operation may be a response to increased storage within and distention of the distal bowel.