Pump-assisted intraoperative colon lavage

We report about a time saving method of on-table lavage of the colon. For irrigation a balloon-catheter is inserted into the colon through a small caecotomy. This catheter is connected to an irrigation pump which we usually use for abdominal lavage in peritonitis. After mobilisation the oral end of the later colonic anastomosis is led over the lateral abdominal wall into a plastic tube. Now a continuous irrigation with a controlled flow-rate of 1 l/min is achieved with the aid of the lavage pump. As irrigation liquid we use Ringer's solution. Pressure is limited by an overflow mechanism. In addition after rearrangement the high irrigation flow of the system allows a thorough cleansing of the rectal stump. Between 1992 and 1995 we carried out intra-operative colonic irrigation using the method set out above in 24 patients. The average volume was 8.9 l of Ringer's solution. The irrigation itself lengthened the operation time by an average of 10 min.     

Effect of fibrin sealant on the integrity of colonic anastomoses in rats with faecal peritonitis

OBJECTIVE: To assess the influence of fibrin adhesive on the healing of colonic anastomoses in rats with and without faecal peritonitis. DESIGN: Controlled study. SETTING: Laboratory for experimental surgery, Erasmus University Rotterdam, The Netherlands. MATERIAL: 120 male Wag/Rij rats. INTERVENTIONS: All rats had a single layer end-to-end anastomosis fashioned with 7/0 polypropylene. Faecal peritonitis was then induced in half of the rats by placement of 200 mg powdered autoclaved rat faeces in the peritoneal cavity near the anastomosis. Rats were allocated to one of four groups (n = 30 in each): 1--control; 2--additional sealing with fibrin glue; 3--peritonitis alone; and 4--peritonitis with fibrin glue. MAIN OUTCOME MEASURES: Body weight, adhesion formation, anastomotic bursting pressure and collagen concentration around the anastomosis on days 2, 4, and 7 in 10 rats from each group. RESULTS: 11 rats died of peritonitis before the experiment was completed. Peritonitis caused increased formation of adhesions and abscesses, with or without fibrin sealant. Bursting pressure at the anastomosis was significantly reduced in peritonitis compared with controls on days 4 and 7, and this was not prevented by fibrin. Sealing of anastomoses resulted in lower bursting pressures on day 4 in control animals. Collagen concentration was significantly reduced in peritonitis with or without fibrin sealant on days 4 and 7, and after fibrin sealing of control anastomoses. CONCLUSION: Faecal peritonitis reduced mechanical strength and collagen concentration of colonic anastomoses, and this was not prevented by additional sealing of the anastomosis with fibrin sealant.     

Intraoperative bowel irrigation improves anastomotic collagen metabolism in the left-sided colonic obstruction but not covering colostomy

This study investigated the effects of intraoperative colonic irrigation and proximal diverting end colostomy after segmental bowel resection in experimental left-colonic obstruction on anastomotic healing. Simple obstruction of descending colon was performed in male Sprague-Dawley rats. After 24 h we performed segmental colonic resection and anastomosis in the control group (n = 15); resection, anastomosis, and covering colostomy in the colostomy group (n = 14); resection and anastomosis after antegrade colonic lavage through cecum by using isotonic saline solution in the irrigation group (n = 13). In rats that were killed 7 days later anastomotic dehiscence and bursting pressure and tissue hydroxyproline concentration at the anastomosis were measured. No significant differences were observed between groups in terms of anastomotic dehiscence, bursting site, or pressure. The hydroxyproline concentration was significantly higher in the irrigation group than the control group (P = 0.025) and the colostomy group (P = 0.029), but no difference was noted between the control group and the colostomy group. These findings suggest that intraoperative antegrade colonic irrigation in the acute left-sided colonic obstruction positively affects collagen metabolism at the anastomotic site; if the anastomosis is performed without bowel cleansing, covering colostomy does not improve collagen metabolism.     

Management of left-sided colonic obstruction by subtotal colectomy and ileocolic anastomosis

OBJECTIVE: To assess complications and functional results of emergency subtotal colectomy with ileocolic anastomosis for acute left-sided colonic obstruction. DESIGN: Retrospective study. SETTING: University hospital, Netherlands. SUBJECTS: 37 patients with acute left-sided colonic obstruction. INTERVENTIONS: Emergency subtotal colectomy with immediate anastomosis (n = 20), Hartmann's procedure (n = 13) or double-loop transverse colostomy (n = 4). MAIN OUTCOME MEASURES: Mortality, morbidity, duration of hospital stay, frequency of defecation, and continence. RESULTS: Morbidity after subtotal colectomy was 10% (n = 2) and mortality 0. There was one anastomotic dehiscence that required a temporary ileostomy. Mean hospital stay was 15 days (range 10-31). All had adequate continence. After 6 weeks mean frequency of defecation was 3/24 hrs (range 2-6). 9 patients died within 2 years of metastatic disease. CONCLUSIONS: Subtotal colectomy with ileocolic anastomosis is a suitable procedure for treating left-sided colonic obstruction provided that pelvic floor function is adequate and a skilled surgeon is available.     

Improved results after aggressive treatment of colonic involvement in necrotizing pancreatitis

BACKGROUND/AIMS: Colonic involvement is a rare but serious event in necrotizing pancreatitis. Early detection of this complication is difficult; a delay of diagnosis may lead to perforation and peritonitis. Two strategies of therapy have been developed in the last few years: an aggressive regimen of early resection and a conservative approach with ileostomy and observation. MATERIALS AND METHODS: Fourteen of 118 patients treated for necrotizing pancreatitis from 1988 to 1995 presented with colonic necrosis. The diagnosis of necrosis was made if the color of the bowel wall demonstrated ischemia or hemorrhagic infarction or pulsations of the mesocolic vessels could not be palpated. The first two patients were treated by a conservative approach the following 12 by immediate large bowel resection. Follow-up results of all surviving patients were obtained. RESULTS: Patients with colonic lesions demonstrated an advanced septic state compared to patients who did not present this complication. Differences in the average Apache 2 scores on admission and the incidence of multiple organ failure were significant (Apache 2 score; 16.6 versus 11.9, p = 0.028, Wilcoxon; multiple organ failure; 71% versus 35%, p = 0.028, Fisher's exact test). Results after establishment of early discontinuity-resection of colonic necrosis compared favorably to those of a conservative strategy (mortality 4/12; 33% versus 2/2; 100%). The overall mortality was 43% (6 of 14 patients). Restorative surgery was performed in 6 patients without substantial morbidity and no mortality. Follow-up results were satisfactory in the majority of the patients. CONCLUSIONS: Early resection of colonic lesions improves results in this dangerous complication of necrotizing pancreatitis.     

Late clinical outcome in a randomized prospective comparison of colonic J pouch and straight coloanal anastomosis

BACKGROUND: Functional outcome after rectal excision with coloanal anastomosis is improved by construction of a colonic J pouch. Present prospective randomized studies lack follow-up beyond 1 year. The aim of this study was to assess the clinical outcome at both short- and long-term follow-up. METHODS: Forty patients with low rectal cancer were randomized prospectively to either J colonic pouch-anal anastomosis or a straight coloanal anastomosis. Clinical assessments were performed 3, 12 and 24 months after colostomy closure using a standard questionnaire and physical examination. RESULTS: There was no significant difference in the complication rate between the two groups. There was a significant (P < 0.01) improvement in frequency of defaecation at 3, 12 and 24 months for patients with a reservoir. Similarly, fragmentation (clustering of stools) was significantly less at 3 and 12 months (P < 0.01) in the reservoir group, and incontinence occurred less frequently in the first year (P = 0.09). By 24 months no patient in either group suffered from major or minor incontinence. CONCLUSION: The functional improvement gained from a colonic reservoir in coloanal anastomosis continues to benefit the patient for at least 2 years.     

Influence of a defunctioning stoma on leakage rates after low colorectal anastomosis and colonic J pouch-anal anastomosis

BACKGROUND: Anal sphincter function is increasingly preserved following rectal excision for cancer and provides a better quality of life for patients than does a permanent colostomy. However, anastomotic complications may cause considerable morbidity and mortality. This retrospective study examined the incidence of anastomotic complications following two forms of reconstruction after resection for mid-rectal cancer: colonic pouch-anal anastomosis (CPAA) and low colorectal anastomosis (LCRA). METHODS: Some 258 consecutive patients with mid-rectal cancers between 6 and 11 cm from the anal verge underwent proctectomy with mesorectal excision and either CPAA or LCRA. The incidence of clinical and radiological leaks was determined in these patients who were considered in three groups: LCRA (defunctioning stoma), LCRA (no defunctioning stoma) and CPAA (all defunctioned). RESULTS: In the LCRA group without a defunctioning stoma, a clinical leak occurred in 17.0 per cent, compared with two of 30 in the LCRA group with a defunctioning stoma. In the CPAA group a clinical leak occurred in 4.9 per cent of patients, which was not significantly different from the rate in those with a defunctioned LCRA. Patients with a non-defunctioned LCRA were more likely to suffer a clinical anastomotic leak (P=0.01), peritonitis (P=0.001) and require unscheduled reoperation (P=0.006) than those with a defunctioned LCRA and/or CPAA. CONCLUSION: The use of a protective defunctioning stoma is advocated in conjunction with LCRAs.     

Transformations of ileo-rectal anastomosis into ileo-anal anastomosis in hemorrhagic rectocolitis. Indications and results

In order to precise the indications and results of this procedure, we assessed 11 cases of transformation of ileorectal anastomosis (IRA) to ileal pouch-anal anastomosis (IPAA) in ulcerative colitis (UC). These 5 men and 6 women had undergone IRA at a mean age of 31 years, 33 months after the diagnosis of UC (range 3-120). Four of these IRA, excluded by an ileostomy, had never been in function: the cause was severe persistent proctitis in 2 cases and anastomotic leakage and peritonitis in 2 cases. The other 7 IRA had been in function during a mean period of 25 months (range 6-45) and were reoperated because of anal sepsis (1 case), low rectal stenosis (1 case), disabling proctitis (4 cases) and rectal dysplasia (1 case). No patient had specific pathologic signs of Crohn's disease. The 11 IPAA were complicated by pelvic sepsis in 3 cases; surgical drainage succeeded in 1 case, but the 2 others needed pouch excision and terminal ileostomy. The diagnosis of Crohn's disease was eventually made in these 2 patients. The 9 patients with functioning IPAA, at a mean follow-up of 40 months (range 12-60), had 5.2 stools per 24 h (range 2-12), 5 patients had no nocturnal stooling, and 6 had a perfect continence. One patient had disabling chronic pouchitis. In conclusion, proctectomy with IPAA is always feasible when a previous IRA for UC had failed or offers poor results, but should be rejected in case of anal involvement, as that may suggest Crohn's disease. This procedure is followed by similar functional results than after primary IPAA.     

Secure anastomoses of the large intestine (especially with transanal drainage

The results of colonic resections were investigated in 356 patients in a retrospective analysis. Special attention was directed to the effectiveness of a transrectal tube, leading to decompression of the anastomosis for the first five days. Under elective conditions, the overall complication-rate was 12.7%. In emergency cases, these complications were 51.5% (one third of these cases had a decompression-tube). The clinical relevant leakage-rate under elective conditions ranged to 1.7%. Postoperative mortality related to surgical complications turned out to be 1.5% under elective conditions. The emergency operations had a high mortality which ranged to approximately 15.2%. No patient with leakage of a colorectal anastomosis died when the transrectal decompression-tube was applied. Such a safety in anastomotic healing of colon and rectum anastomoses can otherwise only be achieved by using the protection of a diverting colostomy or ileostomy. The use of the transrectal decompression-tube also avoids stomal complications and the second operation. There is no indication for the decompression-tube in emergency operations with purulent or faecal peritonitis. In these cases a fundamentally different treatment is mandatory.     

Primary resection with antegrade colonic irrigation and peritoneal lavage versus subtotal colectomy in the management of obstructed left colon cancer

Between 1980 and 1996 122 patients with acutely obstructed resectable carcinomas of the colon and rectum were treated in our hospital. Ninety-four has undergone one stage operation of immediate resection and primary anastomosis without proximal colostomy. Intraoperative colonic irrigation was performed in 34 patients, subtotal/total colectomy in 30 patients, right hemicolectomy in 30 patients. There were 2.3 and 1 operative deaths, respectively. The average hospital stay for the survivors was 19.8 days in the primary resection and anastomosis group, and 41.0 days in staged operation group. Concerning the possibility of multiple lesions the authors recommend subtotal/total colectomy except for tumours localized in the sigma where they apply total colectomy only when the proximal part of the colon is necrotized or filled with solid stool.     

The emergency treatment of perforated colonic diverticula

The authors report their experience of the treatment of 43 cases of perforated colonic diverticula. The operations were: 12 primary resections-anastomoses; 7 resections-anastomoses with protective colostomy; 2 operations of suture and drainage; 22 Hartmann's resections. The authors believe that Hartmann's resection is the operation of first choice in cases of diffuse or stercoraceous peritonitis. This operation another the removal of the sick part of intestines without exposing the patient to the possible complications of an operation "at risk", and allows a late recanalization destitute of risk: in our experience 13 cases of 22 (59%).     

MPK38 expression is upregulated in immature T cells activated by concanavalin A

Between 1974 and 1994, 25 colonic interposition procedures were performed for esophageal replacement in 23 cases of esophageal atresia (EA) and 2 corrosive strictures. Nine patients had one-stage and 16 had two-stage reconstructions. The transthoracic route was used in 16 cases (64%) and the retrosternal route in 9 (36%). Average age at the time of operation in EA patients was 17 months (range 12-33), and the children with corrosive injuries were 3 and 6 years old. Mean age at follow-up was 11.8 years (2.3-20.5 years). There was no mortality in the series. One patient developed full-graft necrosis and had a gastric pull-up procedure later. One child had partial graft necrosis (3 cm at the cervical end), however, enough colon was available for reconstruction. Ten patients developed a leak from the cervical anastomosis (40%) and 7 developed a stricture at the cervical esophago-colonic anastomosis (28%). The strictures were treated by repeated esophageal dilatation, and 3 patients required revision of the anastomosis (12%). Other complications included acid reflux in 2 cases (8%), small-intestinal obstruction in 1 (4%), redundancy of the colon in 1 (4%), and chest infections in 2 (8%). Follow-up included assessment of the patient's symptoms, serial growth measurements (height and weight), and where relevant, endoscopy and a contrast swallow or meal. There was a 52% improvement in weight and height percentiles post-operatively. Each of the 19 patients who had barium swallows showed rapid transit and emptying without any significant delay or hold-up. Overall long-term results were excellent in 13 patients (52%), good in 7 (28%), and fair in 5 (20%). The colon conduit thus provides an excellent substitute esophagus in pediatric patients.     

Ultrasonographically-guided fine-needle aspiration cytology in the diagnosis of colonic lesions

BACKGROUND: The use of fine-needle aspiration cytology (FNAC) in the diagnosis of colonic lesions was investigated. METHODS: Some 22 patients (median age 71 years) with a colonic lesion identified on abdominal ultrasonography underwent ultrasonographically-guided FNAC using a 21-G needle. The sample was checked immediately by a cytopathologist for adequacy. RESULTS: Eighteen patients had colonic carcinoma; aspiration cytology detected malignant epithelial cells consistent with colonic carcinoma in 17 patients and severely dysplastic cells in one patient. The sensitivity and specificity of ultrasonographically-guided FNAC in the diagnosis of colonic carcinoma was 94 and 100 per cent respectively. The remaining four patients had a diagnosis of ileocaecal tuberculosis, ileocaecal Crohn's disease, and metastatic adenocarcinoma in the liver with no identifiable primary (two patients). One demonstrated granulomata, grew acid-fast bacilli and the patient was treated for tuberculosis. One had inflammatory cells and the patient was found to have Crohn's disease on histology. The remaining two patients had confirmed metastatic adenocarcinoma in the liver on aspiration cytology but suspected colonic lesions were found to be benign on cytological examination and no primary lesion was subsequently demonstrated. There were no complications of FNAC and patients complained of minimal discomfort. There has been no evidence of tumour recurrence with a median follow-up of 12 (range 1-25) months. CONCLUSION: Ultrasonographically-guided FNAC is a valid method for the diagnosis of colonic tumours.     

Primary anastomosis in the treatment of acute disease of the unprepared left colon

Between June 1, 1990 and December 31, 1996, 58 consecutive patients with unprepared colons were urgently explored for nontraumatic disease with intent to proceed with primary left-sided colonic anastomosis. Unprotected anastomoses were not attempted in 15 patients. The causes of exclusion included preoperative and intraoperative shock in three patients, and three patients were on long-term high-dose steroids, four had gross fecal contamination of the peritoneal cavity, four had large pelvic abscesses, and one had ischemic colitis. All 43 patients undergoing anastomosis without protective colostomy had stapled anastomoses. Indications included complicated diverticular disease in 32 cases. There were nine cases of obstruction from colorectal carcinoma and one obstruction due to sigmoid volvulus. There was one case of perforation from pseudomembranous enterocolitis. The most common complications were: atelectasis in nine cases, wound infection in two cases, and prolonged ileus in two cases. Pelvic abscess occurred in one case. There was one wound dehiscence. There was one anastomotic dehiscence, and there was no mortality. Operative time averaged 85 minutes and hospital length of stay 9.7 days. Primary anastomosis of the unprepared left colon is safe in most urgent and emergent situations, thus avoiding the significant morbidity and cost of colostomy closure.     

Perioperative predictors of colonic ischemia after ruptured abdominal aortic aneurysm

PURPOSE: Colonic ischemia and colonic resection occur frequently after ruptured abdominal aortic aneurysm (rAAA). The purpose of this study was to identify the perioperative risk factors that might help to determine earlier in the postoperative period which patients are at risk for colonic ischemia and colonic resection. METHODS: The medical records of the 43 patients who underwent repair of rAAA from January 1989 to November 1997 were reviewed. The data were reviewed for the following factors: acidosis, pressor agents, lactate levels, guaiac status, cardiac index, coagulopathy, early postoperative bowel movement, the lowest intraoperative pH level, the temperature at the conclusion of the case, the location and duration of aortic cross clamping, the amount of fluid boluses administered after surgery, the amount of packed red blood cells administered during the case, and the average systolic blood pressure at admission and during surgery. Univariate analysis was performed with Fisher exact test, chi2 test, and Student t test. Multivariate analyses also were performed with the variables that were found to be significant on the univariate analysis. RESULTS: Thirteen of the 43 patients (30. 2%) had colonic ischemia, and seven of the 13 underwent colonic resection (53.8%). The overall mortality rate was 51.2% (22/43) five of the deaths were intraoperative and excluded from the study. In a comparison of the patients who had colonic ischemia with those who did not, statistically significant differences were found in the following variables: average systolic blood pressure at admission 90 mm Hg or less, hypotension of more than 30 minutes' duration, temperature less than 35 degreesC, pH less than 7.3, fluid boluses administered after surgery 5 L or more, and packed red blood cells 6 units or more. Multivariate analysis indicated that the number of these variables present correlated significantly with the positive predicted probability of colonic ischemia occurring. No patient with two factors or fewer had an ischemic bowel, and the positive predictive probability of colonic ischemia for those patients with six factors was 80%. CONCLUSION: The results of this study show that: (1) colonic ischemia after rAAA may be predicted with the presence of two or more specific perioperative factors, (2) the lack of a guaiac-positive bowel movement may be misleading for the early diagnosis of colonic ischemia, and (3) more than 50% of the patients with colonic ischemia will require a colonic resection. We recommend that any patient with rAAA with more than two perioperative factors undergo sigmoidoscopy every 12 hours after surgery for 48 hours to rule out colonic ischemia without waiting for early or guaiac-positive bowel movement.     

Surgical treatment of colonic diverticulitis: a report of 205 cases

In a series of 205 patients treated for colonic diverticulitis, 101 presented acute complications, 35 chronic complications and 69 attacks of diverticulitis without complications. The treatment prescribed for the acute septic complications (generalized peritonitis, perisigmoidic abscess) as well as for acute occlusions consists of two-stage surgery: drainage and emergency colostomy, then secondary colectomy in elective conditions. Massive incoercible hemorrhages were treated by emergency hemostatic resection, guided by selective mesenteric arteriography. Chronic complications (inflammatory stenosing tumor, external or internal fistulas) are ideally treated by a one-stage colic resection. As postoperative mortality and morbidity rates are high and caused by acute conditions, it is justifiable to perform a prophylactic colic resection.     

Model of implantation of tumor cells simulating recurrence in colonic anastomosis in mice

PURPOSE: Local recurrence after colorectal cancer surgery is usually perianastomotic. An experiment was designed to investigate whether free intraluminal cells can penetrate through a colonic anastomosis and thereby cause local recurrence. METHODS: BALB/c and C57/BL mice underwent ascending colotomy followed by watertight anastomosis. Thereafter, CT-26 murine colon carcinoma cells were injected into the cecal lumen 2 cm proximal to the anastomosis of syngeneic BALB/c mice, whereas B-16 murine melanoma cells were injected in the same fashion into C57/BL mice. Control animals without anastomosis received similar injections. Animals were killed 24 hours, 72 hours, and 30 days after surgery and were checked for tumorigenesis. RESULTS: Results of peritoneal fluid cytology were negative after 24 hours, whereas after 72 hours cancer cells were identified in the peritoneal fluid of 80 percent of mice with colotomy and anastomosis compared with 20 percent of control mice. Thirty days after surgery, 11.1 percent of the control BALB/c mice developed pericecal tumor growth, similar to the overall rate of murine melanoma in C57/BL. In mice with anastomoses, perianastomotic tumor growth was observed in 47.5 percent of BALB/c mice (P < 0.001) and was correlated with the number of injected cells. Tumor growth reached approximately 75 percent tumor take with high cell densities, whereas in C57/BL mice no difference was found between the experimental and control groups. CONCLUSIONS: The findings suggest that free intraluminal cancer cells of colonic origin may penetrate through watertight anastomoses and implant on the anastomotic or peritoneal surface and initiate tumor growth. This anastomotic penetration is cell-mass dependent. The reported experimental model is simple, reproducible, and advantageous for studies of colonic anastomosis.     

Purification and characterization of a cytotoxin from Enterobacter cloacae

OBJECTIVE: To document our evolving surgical management of colonoscopic perforation and examine factors crucial to the improvement of patient care. DESIGN: We conducted a computer-based retrospective analysis of medical records (1980 through 1995). MATERIAL AND METHODS: Among 57,028 colonoscopic procedures performed, 43 patients (0.075%, or 1 perforation in 1,333 procedures) had a colonic perforation. Two additional patients were treated after colonoscopy performed elsewhere. The outcomes analyzed included surgical morbidity and mortality. RESULTS: Twenty-six women and 19 men who ranged in age from 28 to 85 years (median, 69) were treated for colonic perforation. More than 80% of perforations occurred during the latter half of the study period because of the increased volume of colonoscopic procedures (8 perforations among 12,581 examinations from 1980 through 1987 versus 35 perforations among 44,447 colonoscopies from 1988 through 1995). Emergency laparotomy was performed in 42 patients (93%). Perforations occurred throughout the colon: right side = 10; transverse = 9; and left side = 23. Three patients without evidence of peritoneal irritation fared well with nonoperative management. Most patients underwent primary repair or limited resection in conjunction with end-to-end anastomosis. In 14 patients (33%), an ostomy was created. One patient underwent laparotomy without further treatment. Intra-abdominal contamination ranged from none (31%) to local soiling (48%) to diffusely feculent (21%). Postoperative complications occurred in 12 patients and were associated with older age (P = 0.01), large perforations (P = 0.03), and prior hospitalization (P = 0.04). No postoperative deaths occurred. CONCLUSION: Despite a consistently low risk of colonic perforation, the increasing use of colonoscopy in our practice has resulted in an increased number of iatrogenic colonic perforations. In order to minimize morbidity and mortality, prompt operative intervention is the best strategy in most patients. Non-operative management is warranted in carefully selected patients without peritoneal irritation.     

Endoscopic polypectomy in the treatment of colonic adenomas containing adenocarcinoma

Fifty-seven adenomas containing adenocarcinoma were removed endoscopically from the colons of 56 patients (36 males and 20 females) with a mean age of 64.5 years. The 13 polyps containing carcinoma in situ were satisfactorily treated by endoscopic resection. In 29 cases, the carcinoma had invaded the head, neck or stalk of the polyp. The outcome was good in every case, including one involving invasion of the resection margin. Follow-up or intraoperative studies disclosed the presence of residual lesion in only 4 patients out of 15 with submucosal invasion. All four had invaded resection margins and incomplete endoscopic excision. Endoscopic polypectomy is a suitable therapeutic option for most colonic adenomas containing a carcinoma provided a complete resection is achieved with wide resection margins, particularly in those cases in which the submucosa is not reached.     

Proliferative patterns of rectal mucosa as predictors of advanced colonic neoplasms in routinely processed rectal biopsies

OBJECTIVES: We sought to determine whether the evaluation of rectal cell proliferation in routinely processed rectal biopsies of apparently normal mucosa can predict the presence of advanced colonic neoplasms. METHODS: Fifty consecutive patients, who did not meet any of the following exclusion criteria, underwent total colonoscopy. Patients with nonadvanced adenomas, inflammatory bowel disease, hereditary predisposition to colonic cancer, or a history of colonic neoplasms were excluded. Patients with neoplasms in the distal 40 cm of the large bowel were also excluded. An adenoma was considered advanced if it had a diameter > 1 cm, or villous or severe dysplasia histology were present. In 26 of the 50 patients (Group A: 16 men, 10 women; mean age, 65 yr) advanced colonic neoplasms (advanced adenomas or cancer) were detected; in the remaining 24 (Group B: 13 men, 11 women; mean age, 66 yr) the large bowel was free of neoplasms. In all patients the proliferative patterns of apparently normal rectal mucosa were evaluated using the monoclonal antibody MIB-1 to assess the expression of Ki-67 antigen in routinely processed tissues. Proliferation index for the entire crypt, as well as proliferation indices for each of the five equal compartments, into which the crypt had been divided longitudinally, were calculated for each patient. RESULTS: The mean proliferation indices were similar between the two groups compared. The mean proliferation index for the upper crypt compartments (4 + 5) in the Group A patients was significantly higher than for those of the Group B patients (p < 0.01). Multivariate stepwise logistic regression analysis revealed that among gender, age, and proliferative parameters, the pattern of cell proliferation in the upper rectal crypt (4 + 5) compartment was the only predictor of advanced colonic neoplasms (beta = 11.01, p < 0.001). CONCLUSIONS: Our data suggest that the evaluation of the upward expansion of the rectal crypt proliferative zone in routinely processed rectal biopsies of apparently normal mucosa appears to predict the presence of advanced colonic neoplasms. These preliminary results should be confirmed in larger studies.