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S D Wexner

Publications and source records attributed to S D Wexner.

At least 55 records · Page 3Linked to original sources

Laparoscopic total mesorectal excision.

After total mesorectal excision for rectal cancer was introduced in 1982, local recurrence rates decreased to 5%. These results were found to be reproducible; therefore, the technique became standard for the treatment of rectal cancer. Laparoscopic surgery for curable colorectal malignancy is still considered investigational. Indeed, the United States National Cancer Institute (NCI) trial excludes rectal carcinoma. The application of laparoscopy to rectal carcinoma must compete with total mesorectal excision, which has obtained favorable results in the last decade. In this review, we assess the adequacy of laparoscopic total mesorectal excision, describe the techniques (both anterior resection and abdominoperineal resection), and discuss their potential advantages.

Abdomen↗

Is obesity a high-risk factor for laparoscopic colorectal surgery?

BACKGROUND: The aim of this study was to assess the outcome of laparoscopic colorectal surgery in obese patients and compare it to that of a nonobese group of patients who underwent similar procedures. METHODS: All 162 consecutive patients who underwent an elective laparoscopic or laparoscopic-assisted segmental colorectal resection between August 1991 and December 1997 were evaluated. Body mass index (BMI; kg/m2) was used as an objective index to indicate massive obesity. The parameters analyzed included BMI, age, gender, comorbid conditions, diagnosis, procedure, American Society of Anesthesiologists classification score, operative time, estimated blood loss, transfusion requirements, intraoperative complications, conversion to laparotomy, postoperative complications, length of hospitalization, and mortality. RESULTS: Thirty-one patients (19.1%) were obese (23 males and 8 females). Conversion rates were significantly increased in the obese group (39 vs 13.5%, p = 0.01), with an overall conversion rate of 18%. The postoperative complication rate in the obese group was 78% versus 24% in the nonobese group (p <0.01). Specifically, rates of ileus and wound infections were significantly higher in the obese group [32.3 vs. 7.6% (p <0.01) and 12.9 vs 3.1%. (p = 0.03), respectively]. Furthermore, hospital stay in the obese group was longer (9.5 days) than in the nonobese group (6.9 days, p = 0.02). CONCLUSION: Laparoscopic colorectal segmental resections are feasible in obese patients. However, increased rates of conversion to laparotomy should be anticipated and the risk of postoperative complications is significantly increased, prolonging the length of hospitalization when compared to that of nonobese patients.

Adolescent↗

Anal manometric predictors of significant rectocele in constipated patients.

The diagnosis of significant rectocele is currently made on the basis of cinedefecographic findings. Clinical examination alone will only allow assessment of the presence but not the significance of a rectocele. Therefore, the aim of this study was to determine if anal manometric findings can predict the significance of a rectocele. All patients with a diagnosis of constipation and rectocele confirmed on cinedefecography between 1992 and 1998 were retrospectively reviewed. Significant rectocele was defined as the presence of three of the following five parameters: rectocele >4 cm in diameter as measured during the evacuatory phase of cinedefecography, rectal and/or vaginal symptoms present for longer than 12 months, persistence of rectal or vaginal symptoms for at least four weeks, despite increased dietary fiber (up to 35 g/day), need for rectal and/or vaginal digitation or perineal support maneuvers for rectal evacuation. Statistical analysis was performed using the Mann-Whitney test and Fisher's exact test. A logistic regression model with stepwise selection was used to determine significant prognostic factors. A total of 305 patients (31 men) with rectocele, with a median age of 68 years (range, 12-89) were identified. Of these, 89 (29.2%) had significant rectoceles. There was no difference in the frequency of significant and non-significant rectoceles with respect to gender or age. However, patients with a significant rectocele compared to those with a non-significant rectocele had higher median first sensation volume (45 vs. 30 ml, p=0.0005), median capacity (160 vs. 120 ml, p<0.0001), and median compliance (10 vs. 8 ml H(2)O/mmHg, p=0.05). Calculations based on a logistic regression model determined that with a first sensation of 100 ml, a capacity of 400 ml, and a compliance of 50 ml/mmHg, the probability of a significant rectocele would be 85%. In conclusion, anal manometric findings may be useful in predicting significant rectocele in constipated patients.

Adolescent↗

Percutaneous postoperative intra-abdominal abscess drainage after elective colorectal surgery.

Intra-abdominal abscesses are a frequent source of morbidity and mortality following both elective and emergent surgery of the alimentary tract. CT-guided percutaneous drainage of intra-abdominal abscess is an alternative to immediate surgical intervention. We studied the clinical characteristics and outcomes of patients undergoing percutaneous drainage of intra-abdominal abscesses arising after elective colorectal procedures. We retrospectively identified 40 patients with postoperative intraabdominal abscess following elective colorectal surgery who underwent CT-guided percutaneous drainage with a Von Sonnenberg sump drain between 1990 and 1998. The most common presenting symptoms were pyrexia in 39 (97%), abdominal tenderness in 32 (80%), guarding in 1 (2.5%) and abdominal mass in 3 (7.5%); no patient had generalized peritonitis. The most common index procedure was proctocolectomy with ileoanal anastomosis and ileal Jpouch in 12 (30%) patients. Drainage was performed using an anterior approach in 32 (80%) and a transgluteal window in 8 (20%) patients. Thirty-five (87.5%) patients had a single collection, while 2 (5.0%) patients had 2 collections and 3 (7.5%) patients had 3 collections. Thirteen (32.5%) patients had perioperative steroids, 30 (75%) had preoperative antibiotics, and 40 (100%) had postoperative antibiotics. Follow-up at a mean of 35.8 days revealed complete resolution of abscess in 26 (65%) patients; 14 (35%) patients had residual or recurrent abscess successfully treated by repeat drainage in 8 patients and requiring laparotomy in 6. Percutaneous CT-guided abscess drainage is an effective method for treating intra-abdominal abscess following elective colorectal surgery. The primary success was 65% after the first and 85% after a second drainage. In conclusion, this technique should be considered as the treatment of choice in patients with localized intra-abdominal abscess without signs of generalized peritonitis.

Abdominal Abscess↗

Secondary reconstruction of an ileal reservoir in patients with failed straight ileoanal pull-through: report of two cases.

The ileoanal reservoir is a widely accepted option for the treatment of mucosal ulcerative colitis and familial adenomatous polyposis. Function of an ileoanal anastomosis without the reservoir may be unacceptable. The aim of this study was to assess the technical feasibility of conversion of a straight ileoanal anastomosis to an ileoanal reservoir anastomosis. Two patients underwent straight ileoanal anastomosis and then underwent subsequent conversion to an ileoanal reservoir anastomosis. A 16-year-old girl with mucosal ulcerative colitis and a 38-year-old woman with familial adenomatous polyposis presented with 20-25 bowel movements per day and severe diarrheal-related symptoms within 11 months of ileoanal anastomosis. In each case, the anastomosis was reversed and an ileal Jpouch was fashioned and anastomosed to the dentate line; there was no postoperative morbidity. The 38-year-old patient reported 4-5 bowel movements per day without the need for any medication at 1-8 months after ileostomy closure. The 16-year-old patient is waiting ileostomy closure. In conclusion, it is technically possible to convert a straight ileoanal anastomosis to an ileoanal reservoir anastomosis with expectations of improvement in function.

Adenomatous Polyposis Coli↗

[Laparoscopic surgery for colon diverticulitis].

BACKGROUND: Laparoscopic surgery is used with increasing frequency to treat colorectal pathologies and some groups have also attempted to treat the complicated forms of diverticulitis (abscesses and/or fistulas). The results reported in the international literature are still controversial, especially in terms of the duration of surgery, the frequency of laparotomic conversions and postoperative morbidity. The aim of this study was to analyse the results of laparoscopic or laparotomic treatment of diverticular disease of the colon in patients admitted to the Department of Colorectal Surgery at the Cleveland Clinic in Florida over a three-year period. METHODS: A retrospective analysis was made of 57 patients with diverticular disease of the colon who were admitted to CCF (Cleveland Clinic Florida) between January 1996 and December 1998 and underwent elective laparoscopic or laparotomic surgery. A comparative analysis was made of the results in the two groups. RESULTS: Of the 57 patients treated only 15 underwent laparoscopic surgery; the majority were treated for uncomplicated diverticulitis. 22 out of 42 patients (53%) undergoing laparotomic surgery presented complicated diverticulitis (abscesses, fistulas or stenosis), whereas 12 out of 15 patients undergoing laparoscopic surgery (80%) were treated for uncomplicated diverticulitis. Statistically significant differences were found in relation to the duration of surgery: 152 min in the laparotomic group vs 209 in the laparoscopic group. No differences were found in the frequency of intraoperative complications, transfusions and the number of drainages inserted (p=0.66). The postoperative period showed significant differences in terms of the reappearance of intestinal peristalsis, use of PCA and postoperative stay. CONCLUSIONS: This retrospective study confirms that the laparoscopic treatment of colon diverticulitis offers a number of advantages: reduced postoperative pain, more rapid recovery of intestinal peristalsis and shorter postoperative stay. Laparoscopic sigma colectomy represents the treatment of choice for diverticulitis in uncomplicated cases.

Aged↗

The pathology and molecular biology of anal intraepithelial neoplasia: comparisons with cervical and vulvar intraepithelial carcinoma.

BACKGROUND: Anal intraepithelial neoplasia (AIN) is a well-described pathological precursor of invasive squamous cell carcinoma which has recently been detected with increasing frequency in immunocompromised patients, particularly those with seropositivity for human immunodeficiency virus (HIV). The epidemiology and natural history of this entity is somewhat unclear, since the overall prevalence in the HIV seronegative population is unknown. DISCUSSION: There is a clear etiological association between AIN and high-risk human papillomavirus (HPV) subtype infection although there is great variability in HPV DNA detection of cytological and histological material in these patients. It appears that there is an antigen-specific hyporesponsiveness by cytotoxic lymphocytes against HPV peptide sequences or recombinant proteins encoded by oncogenic HPV subtypes in these patients, which is dependent upon the stage of their HIV-associated disease. Although the molecular biology of AIN and cervical or vulvar intraepithelial neoplasia are comparable, in AIN there is less significance of tumor suppressor gene mutations, proto-oncogenic growth factor activation, and genomic instability. CONCLUSION: Current concepts in the epidemiology and etiology of AIN are discussed, as well as its immunological response in the HIV-positive population, drawing parallels where possible between other HPV-related preinvasive disorders, and concluding with a suggested management protocol

Anus Neoplasms↗

Trocar site recurrence in laparoscopic surgery for colorectal cancer.

BACKGROUND: Laparoscopic colorectal surgery has been associated with less postoperative pain, an early return of bowel function, a shorter period of hospitalization and disability, and better cosmetic results. However, the application of laparoscopic techniques to the curative resection of colorectal cancer is still controversial, owing to reports of cancer recurrence at the port site wounds. The accumulation of numerous such reports in a relatively short period raised concern that there might be an extraordinary high rate of port site metastases after laparoscopic colorectal surgery. This concern has led to intense clinical and basic research aimed at determining the incidence and causes of wound recurrence and developing preventative measures to address this problem. Despite these efforts, it is still not clear whether port site metastasis is really an inherent drawback to laparoscopic cancer surgery. METHODS: In this review of the literature on port site metastasis, we gathered data from clinical series of laparoscopic surgery for colorectal cancer. We eliminated series of <50 patients, since they may be flawed by the learning curve required for this technically demanding procedure. RESULTS: The rate of port site recurrences in the 1737 patients who participated in these series was 1%. Although the methods and criteria for patient selection in these studies varied, this figure appears to be comparable to the incidence reported for other malignancies and for laparotomies performed to treat colorectal cancer. CONCLUSION: This review suggests that wound recurrence may actually be the result of an unfortunate learning curve, rather than an inherent concern. However, we must await the final results of large randomized studies before drawing any definitive conclusions.

Adenocarcinoma↗

Current attitudes in laparoscopic colorectal surgery.

BACKGROUND: In this study, we set out to examine the current attitudes among surgeons toward laparoscopic colorectal surgery (LCS). METHODS: A total of 3628 questionnaires were sent to all North American members of the Society of American Gastrointestinal Endoscopic Surgeons (SAGES) and the American Society of Colon and Rectal Surgeons (ASCRS); 40% of the members of each society responded (B15 respondents). RESULTS: Currently, 85% of the respondents perform laparoscopic surgery; LCS was performed by 48% of the respondents in 21% of their patients. Although 35% of the members of SAGES have increased the number of laparoscopic colorectal operations they perform in the last 3 years, only 26% of ASCRS members did so. Our findings showed that 74% of the surgeons who perform LCS do so for diverticular disease, 68% for colonic polyps, 61% for villous adenoma, and 36% for ileal Crohn's disease. However, only 15% operate for the cure of carcinoma of any stage (16% of SAGES members and 11% of ASCRS members), whereas 8.5% and 7% operate for the cure of all upper and lower rectal carcinomas, respectively. Thirty-six percent of the surgeons who perform LCS for cancer have done between one and 10 curative resections, 8% have done 11-20 procedures, and 14% have done >20 procedures. There were 80 cases of port site recurrence reported by 4.4% of surgeons. Although 56% of the respondents would themselves undergo laparoscopic colorectal surgery for a rectal villous adenoma, only 9% would do so for a distal-third rectal carcinoma (12% of SAGES and 5% of ASCRS respondents). CONCLUSIONS: The overall percentage of respondents performing LCS has decreased over the last 3 years; moreover, surgeons are more hesitant to perform laparoscopic surgery for the cure of colonic cancer. Due to the overall low response rate, the fact that 4.4% of those surgeons who did respond have seen port site recurrences does not allow any conclusions to be drawn about the prevalence of this problem.

Adenoma↗

Laparoscopic surgery for inflammatory bowel disease.

BACKGROUND: Common laparoscopic colorectal procedures in patients with Crohn's disease include ileocolic resection and subtotal colectomy. The aim of this study was to compare and contrast the results of these two procedures. METHODS: Patients who underwent one of these procedures between June 1992 and January 1999 were identified and included in the study. Statistical analysis was performed using the Mann-Whitney test, Student's t-test, or Fisher's exact test. RESULTS: In all 109 patients (63 women and 46 men) with an average age of 36.7 years (range, 15-74) underwent ileocolic resection (ICR), while 21 patients (16 women and five men) with an average age of 36.5 years (range, 18-77) underwent subtotal colectomy (STC) (p = NS). There were 14 intraoperative complications, eight (7%) in the ICR group and six (29%) in the STC group (p = 0.01). Total operative time was 167 min (range, 90-285) in the ICR group and 231 min (range, 140-340) in the STC group (p < 0.01). Despite this difference in operating time, the hospital stays were very similar at 8.8 days (range, 3-27) and 8.8 days (range, 3-14) (p = NS). In 19 (17%) of the ICR patients and five (24%) of the STC patients, their procedure was converted to a laparotomy (p = NS). In the ICR group, 20 of the patients (18%) had surgery-related postoperative complications, including five anastomotic leaks. In the STC group, six of the patients (29%) had surgery-related complications, including two anastomotic leaks (p = NS). CONCLUSION: Although STC is a far more extensive procedure than ICR, the overall postoperative complication rate is not significantly different between the two groups; however, we found that there were more intraoperative complications associated with STC.

Adolescent↗

A prospective analysis of 13,580 colonoscopies. Reevaluation of credentialing guidelines.

BACKGROUND: The aims of this study were to assess the safety and efficacy of surgeons performing colonoscopy, and to use the results to reevaluate currently available credentialing guidelines. METHODS: A prospective outcomes study was designed to include all members of the Society of American Gastrointestinal Endoscopic Surgeons (SAGES). End points were related to the efficacy and safety of colonoscopy. Credentialing guidelines were reviewed. RESULTS: Between April 1998 and September 1999 13,580 colonoscopies were prospectively entered into a database. The most common indications were rectal bleeding, colonic polyps, and change in bowel habits. The colonoscopy was normal or revealed only diverticulosis or nonspecific inflammation in 8,473 (62.4%), lower gastrointestinal bleeding in 4 (0.03%), polyps in 4,645 (34.2%), and tumors in 458 (3.4%) patients. The most common biopsy methods for polyps or tumors were the snare (n = 1,728; 34%), the hot (n = 1,600; 31%), and the cold (n = 1,340; 22%) procedures. The colonoscopy was complete in 12,495 cases (92%), requiring a mean procedure time of 22.7 min (range, 1-170 min). Intraprocedural complications included arrhythmia (n = 14; 0.1%), bradycardia (n = 115; 0.8%), hypotension (n = 171; 1.2%), and hypoxia (n = 806; 5.6%). Postprocedural complications were seen in 27 patients (0.2%). Bleeding (n = 10; 0.07%) was managed by observation alone (n = 9; 0.06%) and repeat colonoscopy with transfusion (n = 1; 0.01%). Perforation (n = 10; 0.07%) was treated successfully by observation with conservative management (n = 5; 0.05%) and surgery (n = 5; 0.05%); severe abdominal pain (n = 4; 0.03%) was managed by observation and conservative therapy; and bronchospasm (n = 2; 0.015%) was managed by observation and supportive care. One single mortality (0.007%) was that of a 70-year-old man with a massive lower gastrointestinal hemorrhage who had a cardiac arrest in the recovery room following colonoscopy. The complication rate was not significantly associated statistically with either the level of experience or the number of prior or annual colonoscopies. However, prior colonoscopic experience did have an impact on the completion rate (p < 0.001) and was inversely proportional to the time to completion (p < 0.001). Similarly, the number of annual colonoscopies affected the completion rate and was inversely correlated with the time to completion (p < 0.001). CONCLUSIONS: This large prospective outcomes study showed that colonoscopy performed by surgeons can be rapidly and successfully done with acceptably low morbidity and mortality. There was no association between experience and complications. However, a minimum of 50 prior colonoscopies and 100 annual colonoscopies were associated with a significant improvement in the rate of completion. There was also a significant correlation between both prior and ongoing annual experience and the time required for the examination. No minimum number of cases can be mandated for credentialing to perform "safe" colonoscopies.

Clinical Competence↗

Long-term follow-up of patients undergoing colectomy for colonic inertia.

PURPOSE: Total abdominal colectomy with ileorectal anastomosis has been the procedure of choice for patients with the established diagnosis of colonic inertia. Previous studies with a limited follow-up of only one to two years have shown acceptable results and a high rate of patient satisfaction. The aim of this study was to evaluate the long-term results of total abdominal colectomy in these patients in terms of complications, bowel function, and overall patient satisfaction. METHODS: Access to the colorectal registry at the Cleveland Clinic Florida identified all patients who underwent total abdominal colectomy for colonic inertia between 1988 and 1993, with a minimum of five-year follow-up. Telephone interviews were designed to assess bowel function, concomitant use of any antidiarrheal medications, postoperative complications, persistence or development of preoperative symptoms such as pain or bloating, and overall satisfaction. Patients were asked to rate their outcome as excellent, good, fair, or poor. RESULTS: Fifty patients underwent total abdominal colectomy for the diagnosis of colonic inertia. Three patients died of unrelated causes and 30 (60 percent) were available for follow-up. The mean follow-up was 106 months, ranging from 61 to 122 months. All 30 patients reported the outcome of surgery as "excellent." The average frequency of spontaneous bowel movements was 2.5 (range, 1-6) per day. During the period of follow-up, six patients (20 percent) required admission for small-bowel obstruction, three of whom (10 percent) required laparotomy. Four patients complained of mild pelvic pain, only one of whom had the onset of pelvic pain postoperatively that persisted until the time of interview. In the other three patients the pain was present preoperatively but had decreased in intensity since the operation. Two patients (6 percent) still required assistance with bowel movements, one by laxatives and the other by enemas. Only two patients (6 percent) needed antidiarrheal medications to reduce bowel frequency. CONCLUSION: This long-term follow-up revealed a high degree of patient satisfaction and very good bowel habits, with an acceptable long-term rate of bowel obstruction. Based on these results, total abdominal colectomy can be recommended to patients with well-established colonic inertia with expectations of sustained benefit up to ten years after surgery.

Colectomy↗

A comparison between dynamic pelvic magnetic resonance imaging and videoproctography in patients with constipation.

PURPOSE: This study attempts to compare the diagnostic efficacy of dynamic pelvic magnetic resonance imaging with that of videoproctography for the presence of rectocele, sigmoidocele, and intussusception as well as the measurement of anorectal angle and perineal descent in constipated patients. METHODS: Patients volunteering for the study and fulfilling the criteria for videoproctography to evaluate constipation were also scheduled for dynamic pelvic magnetic resonance imaging. Patients undergoing videoproctography were placed in the left lateral decubitus position, after which 50 ml of liquid barium paste was introduced into the rectum. After this, approximately 100 ml of thick barium paste similar to stool in consistency was injected into the rectum, and the patient was instructed to defecate while video images were taken. For dynamic pelvic magnetic resonance imaging, air, to be used as contrast, was allowed to accumulate in the rectum via examination with the patient in the prone position. A capsule was taped to the perineal skin immediately posterior to the anal orifice for marking. Sagittal and axial T1 images were obtained through the pelvis at 8-mm intervals with dynamic breathhold sagittal images of the anorectal region obtained at rest and during strain and squeeze maneuvers. Total acquisition time per maneuver was approximately 19 seconds. The tests were performed by different examiners blinded to the result of the other evaluation. The investigations were independently interpreted, findings compared, and patients questioned regarding their impression of dynamic pelvic magnetic resonance imaging and videoproctography. RESULTS: From June 1996 to April 1997, 22 patients (15 females) with a mean age of 68 (range, 21-85) years underwent both videoproctography and dynamic pelvic magnetic resonance imaging. Dynamic pelvic magnetic resonance imaging was only able to detect 1 of 12 (8.3 percent) anterior rectoceles and one of two (50 percent) posterior rectoceles identified by videoproctography. It failed to recognize any of the rectoanal intussusception (zero of four) but did show 9 of 12 (75 percent) sigmoidoceles. Significant discrepancy of measurement of the anorectal angle and perineal descent exists between the two studies, and dynamic pelvic magnetic resonance imaging was not able to detect any (0 of 11) of the patients with increased fixed perineal descent and only half (one of two) of the patients with increased dynamic perineal descent noted on videoproctography. All 22 patients preferred dynamic pelvic magnetic resonance imaging over videoproctography because of greater comfort. CONCLUSION: Occasionally, the increased cost of new technology can be justified by the enhanced diagnostic yield. The ability to avoid unnecessary surgery or, conversely, to continue to search for otherwise occult pathology that can be surgically corrected justifies routine application of these new tools. However, this study has shown that, despite a cost of approximately ten times more for dynamic pelvic magnetic resonance imaging than for videoproctography, no clinical changes were made. Thus, on the basis of this study, we cannot endorse the routine application of dynamic pelvic magnetic resonance imaging for the evaluation of constipated patients. In certain selected individuals, it may play a role, but further study is necessary to clarify its exact role.

Adult↗

Colonic J-pouch function in rectal cancer patients: impact of adjuvant chemoradiotherapy.

PURPOSE: The colonic J-pouch technique of reconstruction optimizes functional outcome after proctectomy with coloanal anastomosis. However, the impact of adjuvant chemoradiation therapy on pouch function in rectal cancer patients has not been investigated. METHODS: From January 1994 to December 1999, 74 patients with midrectal or low rectal tumors (less than 10 cm from the anal verge) underwent a proctectomy with coloanal anastomosis with colonic J-pouch reconstruction. Chemoradiation was offered in patients with Stage II and III disease. Radiation therapy was administered using a four-field technique including the anal canal, for a total dose of 50.4 Gy (1.8 Gy/fraction/day). Fifteen patients (20 percent) died with metastatic disease, five (6.8 percent) died of other causes without evidence of recurrence, and five (6.8 percent) were lost to follow-up. In addition, two patients had local recurrence (2.7 percent) at the time of follow-up. Forty-five of 47 eligible patients (96 percent) responded to a questionnaire designed to evaluate specifically the degree of continence and pouch evacuation. RESULTS: The mean age of patients was 68.9 (range, 42-88) years and the mean duration of follow-up was 28.8 (range, 1-69) months. There were 28 patients in the surgery alone group and 17 patients who received either preoperative (13) or postoperative (4) adjuvant chemoradiation therapy. Patients in the surgery alone group had a significantly better degree of continence (mean +/- standard deviation continence score: 18.1 +/- 2.9 vs. 13.3 +/- 4.1, P < 0.001) and were less likely to experience evacuatory problems (mean +/- standard deviation evacuation score: 21.3 +/- 3.7 vs. 16.4 +/- 3.5, P < 0.001). Use of a pad was more frequent in the chemoradiation therapy than in the surgery alone group (53 vs. 18 percent, P = 0.02). The incidence after functional disorders was also more frequent in the irradiated group of patients: incontinence to gas (76 vs. 43 percent, P = 0.03), to liquid stool (64 vs. 25 percent, P = 0.01), and to solid stool (47 vs. 11 percent, P = 0.01). Moreover, irradiated patients reported more frequent pouch-related specific problems, such as clustering (82 vs. 32 percent, P = 0.001), and sensation of incomplete evacuation (82 vs. 32 percent, P = 0.001). Finally, regression analysis demonstrated that radiation-induced sphincter dysfunction was progressive over time. CONCLUSIONS: Both preoperative and postoperative chemoradiation therapy adversely affects continence and evacuation in patients with colonic J-pouch. Because radiation-induced damage to the normal tissues is known to be cumulative over time, long-term progressive dysfunction of the anal sphincter and neorectum are causes of concern. Consideration should be given to excluding the anal canal from the field of irradiation in patients with Stage II and III rectal cancer, whenever a sphincter-preserving procedure is planned.

Adult↗

Does limited placement of bioresorbable membrane of modified sodium hyaluronate and carboxymethylcellulose (Seprafilm) have possible short-term beneficial impact?

PURPOSE: The aim of the study was to assess the impact of sodium hyaluronate and carboxymethylcellulose membrane (Seprafilm) on postoperative intestinal obstruction as judged by the rates of bowel obstruction and laparotomy for bowel obstruction. A secondary aim was to assess early postoperative morbidity. METHODS: All patients who had Seprafilm placed during colorectal surgery between June 1993 and October 1998 were included in the study group and compared with a matched group of patients without Seprafilm. All patients were assessed for intestinal obstruction and complications by telephone interview and chart review. Statistical tests for independence were used where appropriate; alpha was 0.05 for all tests, and the two groups were tested for case matching. Fisher's exact test was used to compare gender distribution, nature of diagnosis (inflammatory vs. noninflammatory), and urgency of surgery (elective vs. emergency). The age distribution, number of prior abdominal surgeries, and operative time were compared by Student's t-test. Approximation of Katz test was used for independent proportions to compare the two groups for early postoperative morbidity and overall incidence of intestinal obstruction and surgical enterolysis. The incidence of intestinal obstruction between the two groups was also compared with Kaplan-Meier product limit method and log-rank test. RESULTS: Two hundred fifty-nine patients in whom Seprafilm was placed were compared with a well-matched control cohort of 179 patients. The two groups did not differ in gender or age. One-half of each group had inflammatory conditions, and approximately 90 percent of each group underwent elective operations. The operative times were similar. Both groups had a similar number of abdominal operations before inclusion (mean = 1.2, both groups). Early morbidity rates were 17.8 percent for the Seprafilm group and 15.6 percent for the controls, with mortality rates of 0.8 percent and 0.0 percent, respectively. There were 12 intestinal obstructions in 12 patients in the Seprafilm group and 12 intestinal obstructions in 11 patients in the control group at a follow-up period of 65 months in the Seprafilm group and 81 months in the control group. Eight of the 12 intestinal obstructions in the Seprafilm group resolved with conservative management while only 5 of 12 in the control group responded without surgery. Thus the enterolysis rate was 1.5 percent in the Seprafilm group and 3.9 percent in the control group, demonstrating a trend in favor of Seprafilm. There were no statistically significant differences in the incidence of either overall or abdominopelvic septic complications between the Seprafilm (3.4 percent) and control (1.1 percent) groups. CONCLUSION: During short-term follow-up in this nonprospective, nonrandomized study, limited placement of Seprafilm did not significantly reduce the need for surgical enterolysis for intestinal obstruction or significantly adversely affect the morbidity rate. However, a long-term, prospective, randomized trial is underway to elucidate these issues.

Adolescent↗

Loss of heterozygosity and HIV infection in patients with anal squamous-cell carcinoma.

PURPOSE: This study was designed to determine whether loss of heterozygosity and/or microsatellite instability correlate with HIV infection and tumor recurrence after chemoradiation therapy in patients with squamous-cell carcinoma of the anus. BACKGROUND: The molecular mechanisms leading to the progression of HIV-related squamous-cell carcinoma of the anus are poorly understood. In particular, genetic alterations responsible for resistance to chemoradiation have important clinical and functional implications. METHODS: In a case-control study, we analyzed normal and tumor DNA samples of four patients with squamous-cell carcinoma of the anus who were successfully treated with chemoradiotherapy and four patients with radio-resistant squamous-cell carcinoma of the anus who required abdominoperineal resection for local recurrence. To determine the presence of microsatellite instability, we used the reference panel of five pairs of microsatellite primers recommended for colorectal cancer specimens. These include the microsatellite markers BAT25, BAT26, D5S346 (APC), D2S123 (hMSH2), and D17S250 (P53). In addition, we used microsatellite markers for loss of heterozygosity analyses that were tightly linked to tumor suppressor genes. These included D3S1611 (hMLH1), D17S513 (P53), D18S46 and 18qTA (DCC/SMAD4), D5S107 (APC), and CA5 (hMSH2). RESULTS: There were two HIV-positive and two HIV-negative patients in each group. Three HIV-positive patients (one in the chemoradiotherapy group and two in the nonchemoradiotherapy group) demonstrated loss of heterozygosity. In the chemoradiotherapy group, one HIV-positive patient demonstrated loss of heterozygosity at the hMLH1 locus. In the nonchemoradiotherapy group, two HIV-positive patients exhibited a total of four instances of loss of heterozygosity. One tumor had loss of heterozygosity at hMSH2 and DCC/SMAD4; another tumor demonstrated loss of heterozygosity at hMSH2 and APC. Microsatellite instability-low was found in two HIV-positive patients. No instances of loss of heterozygosity and microsatellite instability were detected in HIV-negative patients. CONCLUSION: Loss of heterozygosity and microsatellite instability, which reflect inactivation of tumor-suppressor genes and genomic instability, occur with increased frequency in HIV-associated squamous-cell carcinoma. These data demonstrate for the first time evidence of loss of heterozygosity at the APC and DCC/SMAD4 gene loci in anal carcinoma. Although the findings presented here need to be expanded in a larger study, the recurrent loss of heterozygosity at D2S123, which was demonstrated in HIV-positive patients with radio-resistant squamous-cell carcinoma of the anus, is notable.

Adult↗

Bowel preparation for colorectal surgery.

PURPOSE: The aim of this study was to assess recent literature regarding bowel preparation for colonoscopy and surgery. METHODS: The study was conducted by an Index Medicus English-language search of articles relevant to both oral mechanical and parenteral and oral antibiotic preparation for elective colorectal surgery and mechanical bowel preparation for colonoscopy. The study period was from 1975 to 2000. In addition, studies of elective colorectal surgery without mechanical bowel preparation were also considered. RESULTS: Although several recent prospective, randomized trials have suggested that elective colorectal surgery can be safely performed without any mechanical bowel preparation, mechanical bowel preparation remains the standard of care, at least in North America at the present time. A recent survey of the members of The American Society of Colon and Rectal Surgeons revealed that the majority currently use sodium phosphate for bowel preparation and use a dual oral antibiotic regimen before elective colorectal surgery, combined with two doses of parenteral antibiotics. Although some of the use patterns are based on prospective, randomized study, others seem founded strictly on habit and theory. CONCLUSIONS: The current methods of bowel cleansing for both colonoscopy and surgery include sodium phosphate and polyethylene glycol; colorectal surgeons practicing in North America currently prefer sodium phosphate. Additional preparation for colorectal surgery includes perioperative parenteral antibiotics and, to a slightly lesser degree, preoperative oral antibiotic preparation. Although some recent prospective, randomized studies have suggested that omission of mechanical bowel preparation for elective colorectal surgery is not only feasible but potentially preferable, caution is recommended before routinely omitting these widely practiced measures, because data to support such routine omission are limited.

Animals↗