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Severity of inflammation is a risk factor for colorectal neoplasia in ulcerative colitis.

BACKGROUND & AIMS: Patients with ulcerative colitis are at increased risk of colorectal cancer. It is widely believed that this is secondary to colonic inflammation. However, the severity of colonic inflammation has never been shown to be a risk factor. METHODS: We devised a case-control study of patients with long-standing extensive ulcerative colitis to examine various potential risk factors for neoplasia. All cases of colorectal neoplasia detected from our surveillance program between January 1, 1988, and January 1, 2002, were studied (n = 68). Each patient was matched with 2 control patients from the same surveillance population (n = 136). Matching was for sex, colitis extent, age at onset, duration of colitis, and year of index surveillance colonoscopy. Segmental colonoscopic and histological inflammation was recorded by using a simple score (0, normal; 1, quiescent/chronic inflammation; and 2, 3, and 4, mild, moderate, and severe active inflammation, respectively). Other data collected included history of primary sclerosing cholangitis, family history of colorectal cancer, and smoking and drug history (mesalamine 5-aminosalicylic acid, azathioprine, and folate). RESULTS: Univariate analysis showed a highly significant correlation between the colonoscopic (odds ratio, 2.5; P = 0.001) and histological (odds ratio, 5.1; P < 0.001) inflammation scores and the risk of colorectal neoplasia. No other factors reached statistical significance. On multivariate analysis, only the histological inflammation score remained significant (odds ratio, 4.7; P < 0.001). CONCLUSIONS: In long-standing extensive ulcerative colitis, the severity of colonic inflammation is an important determinant of the risk of colorectal neoplasia. Endoscopic and histological grading of inflammation could allow better risk stratification for surveillance programs.

Adolescent↗

Evaluation of the microbicidal efficacy of Steris System I for digestive endoscopes using GERMANDE and ASTM validation protocols.

In the light of more and more invasive procedures being carried out in digestive endoscopy using sterile devices, it appears necessary to put in place a process of endoscope reprocessing capable of ensuring the complete elimination of micro-organisms contaminating the device. We undertook a study of the microbial efficacy of STERIS SYSTEM 1 (SS1) which purports to achieve this objective. The channels of a gastroscope and a colonoscope were contaminated with suspensions of Pseudomonas aeruginosa, Aspergillus niger and Bacillus subtilis spores. Two procedures were then followed: (1) manual washing only, and (2) treatment in SS1 without prewashing. Recoveries of organisms were made from each channel according to a standard methodology to discover any survivors. Contamination controls we re assessed to measure the logarithmic reduction between the initial contamination and that recovered from the channels. Six cycles per micro-organisms, per type of endoscope, and per type of procedure were carried out. From an initial contamination leve l of 10(6) micro-organisms per endoscope, no micro-organisms were recovered in 35 of the 36 cycles with the SS1. In one cycle with the colonoscope, three B. subtilis organisms were recovered from the channels. Washing only gave microbial reductions which varied according to the micro-organism tested. The maximum reduction with washing alone was by a factor of 10(3 +/- 0.1)for B. subtilis and the minimum reduction factor was 10(3 +/- 0.3)for P. aeruginosa. Considering the results obtained with SS1 without prewashing and the efficacy obtained from washing only, the washing step offers an additional antimicrobial assurance reduction factor of between 10 and 103.1. This study shows that SS1, integrated into an overall reprocessing procedure for digestive endoscopes, is capable of delivering the complete elimination of contaminating micro-organisms in a reduced time and eliminates the toxic risk of reprocessing associated with aldehyde based disinfectants.

Disinfectants↗

Sigmoid stiffener for decompression tube placement in colonic pseudo-obstruction.

BACKGROUND AND STUDY AIMS: Decompression tube placement improves outcome in colonic pseudo-obstruction (CP) which is refractory to conservative measures, especially if the decompression tube is placed proximal to the hepatic flexure. We evaluate the ability of a sigmoid stiffener to facilitate more proximal colonoscopy and decompression tube placement. PATIENTS AND METHODS: A sigmoid stiffener is used in the standard fashion during colonoscopic decompression for pseudo-obstruction. After cecal wire placement, the colonoscope is withdrawn, leaving the stiffener and wire in place. By passing through the stiffener, an over-wire decompression tube can avoid sigmoid looping. We compared proximal extent of colonoscopy, tube position, endoscopy time, and patient outcomes using a sigmoid stiffener, with a control group of patients treated previously. Patients with colonic ischemia were excluded. RESULTS: Using this technique, nine consecutive colonoscopies and decompression tube placements reached the right colon. Significantly, only three of seven control colonoscopies and two control decompression tubes did so. However, improvements in procedural time and patient outcome did not reach statistical significance. No complications occurred. CONCLUSION: The use of a sigmoid stiffener during colonic decompression allows more proximal colonoscopy and decompression tube placement, with possible clinical benefit. We do not use this technique in the setting of left colon ischemia.

Adult↗

A randomized, blinded, prospective trial to compare the safety and efficacy of three bowel-cleansing solutions for colonoscopy (HSG-01*).

BACKGROUND AND STUDY AIMS: There are conflicting data regarding the optimal bowel preparation for colonoscopy. This study was carried out to compare the efficacy, safety, and tolerability of three widely used bowel lavage solutions: the standard polyethylene glycol-electrolyte solution based on the GoLytely formulation (PEG-EL1; Klean-Prep); a sulphate-free PEG-EL solution based on the NuLytely formulation (PEG-EL2, Endofalk); and a sodium phosphate preparation (NaP, Fleet Phospho-Soda). PATIENT AND METHODS: A total of 185 consecutive patients scheduled for elective colonoscopy were prospectively randomly assigned to undergo pre-colonoscopic bowel cleansing with either 4 l of PEG-EL1 (n=64), 3 l of PEG-EL2 (n=59), or 90 ml of NaP (n=62). The quality of preparatory colonic cleansing for each segment from the rectum to the ascending colon was scored on a five-level rating scale (1, very good to 5, very poor) by endoscopists who were blinded with regard to the type of preparation used. The primary outcome measure for the comparison of treatments was the "worst" score in any of the rated bowel segments. Safety and tolerability were evaluated by means of a symptom questionnaire completed by each patient immediately before the procedure. RESULTS: Of the 185 patients who were randomly assigned to one of the three treatments, 175 underwent colonoscopy and 173 were evaluable with regard to efficacy - 59, 54, and 60 patients treated with PEG-EL1, PEG-EL2, and NaP, respectively. The treatment groups were comparable with regard to the baseline characteristics. PEG-EL1 was statistically significantly superior to the other treatments in relation to the "worst cleansing" score ( P</=0.003). In addition, colonoscopic visualization was markedly better in each of the five bowel segments and general "very good" or "good" ratings were achieved in more than 90 % of patients treated with PEG-EL1. The percentages were consistently lower in the other two groups, particularly in the ascending colon. With the exception of the sigmoid, the differences in all segments of the large bowel were statistically significant (P</=0.04). Patient satisfaction was comparable between the treatment groups. Adverse events (mainly nausea/vomiting and abdominal pain) and deviations in laboratory values occurred more frequently in the NaP group. CONCLUSIONS: Preparatory PEG-EL1 (Klean-Prep) was significantly superior to PEG-EL2 (Endofalk) and NaP (Fleet Phospho-Soda) in achieving effective cleansing of the entire colon prior to colonoscopy. On the basis of these data, PEG-EL1 can be regarded as the "gold standard" for bowel cleansing prior to colonoscopy.

Adolescent↗

Invasive colorectal cancer detected up to 3 years after a colonoscopy negative for cancer.

BACKGROUND AND STUDY AIMS: Colonoscopy has replaced barium enema as the primary method for direct diagnosis of colorectal cancer, but detection may fail, and the reasons for this are not completely understood. PATIENTS AND METHODS: In order to analyze the accuracy of colonoscopy for detecting invasive colorectal cancer, 7365 colonoscopic examinations were matched with the most accurate local government population-based cancer registry in Japan. RESULTS: In 15 colonoscopic examinations, patients were not diagnosed as having invasive colorectal cancer, but disease of this type was detected within 3 years of the examinations (false-negative examinations). During the same period, 233 colonoscopies were identified as true-positive examinations. The false-negative rate for detecting invasive colorectal cancer with colonoscopy was 6% at 3 years. The false-negative rate was significantly higher in individuals between 60 and 69 years of age and in invasive cancers located to the right of the splenic flexure. CONCLUSIONS: Colonoscopists should receive adequate training in achieving easy cecal intubation, detecting small or flat lesions, and carrying out adequate biopsies.

Colonoscopy↗

Treatment of bleeding colonic diverticula by endoscopic band ligation: an in-vivo and ex-vivo pilot study.

BACKGROUND AND STUDY AIMS: Angiographic and surgical therapy are standards of care for persistent diverticular bleeding. Colonoscopic intervention using epinephrine injection, multipolar electrocautery, and placement of an Endoclip has not gained widespread acceptance due to concerns about complications,and the widespread management of severe lower gastrointestinal bleeding by surgeons and interventional radiologists. The utility of colonoscopic band ligation for control of diverticular bleeding was evaluated both in vivo and ex vivo. PATIENTS AND METHODS: Endoscopic band ligation of diverticula was performed on surgical resection specimens and in patients with actively bleeding colonic diverticula. RESULTS: In the in-vivo study, active diverticular bleeding was completely controlled in four patients by endoscopic band ligation. In two cases, a visible vessel was seen on the everted and banded diverticulum. Procedure time ranged from 45 to 140 min. The total lengths of hospital stays for the four patients were 2, 6, 14, and 35 days. The long hospital stays (> 7 days)were associated with non-gastrointestinal co-morbidity. There were no acute complications of band ligation. No rebleeding or need for surgery occurred during a follow-up period of 12 months in any of the patients. In the ex-vivo study, 11 diverticula were successfully everted and banded in five of nine surgical specimens (one right colon and four left colons). Mucosa was identified in all of the "banded" segments. Ten of 11 ligated diverticula revealed evidence of blood vessels or submucosal tissue. The presence of subserosal fat was suggested in three of the 11 "banded" segments, and none of the ex-vivo ligated diverticula contained muscularis propria or serosal involvement. There was no evidence of perforation. CONCLUSIONS: Both in-vivo and ex-vivo data suggest that endoscopic band ligation may be a safe and effective therapy for actively bleeding colonic diverticula.

Aged↗

Sympathovagal balance fluctuates during colonoscopy.

BACKGROUND AND STUDY AIM: Colonoscopy is a common gastroenterological procedure for investigation of the bowel. The main side effects of colonoscopy are pain during investigation, cardiovascular complications and very rarely even death. The aim of this study was to compare the continuous fluctuation of heart rate variability (HRV) components during colonoscopy under normal conditions, analgesia/sedation, and total intravenous anesthesia. PATIENTS AND METHODS: 37 consecutive patients (aged 35 - 65), were randomly allocated to three groups: no sedation (control group 1); analgesia/sedation (group 2); and total intravenous anesthesia (group 3). Holter electrocardiography and subsequent frequency domain analysis were undertaken. The low-frequency (LF, 0.04 - 0.15 Hz) and the high-frequency (HF, 0.15 - 0.40 Hz) components were estimated using spectral analysis in the usual way. Normalized units (nu) were calculated from the following equations: LFnu = LF/(LF + HF), and HFnu = HF/(LF + HF). RESULTS: Groups 2 and 3 were found to have a significantly lower HFnu and higher LFnu than group 1 essentially throughout the procedure. A one-way analysis of variance and t-test confirmed that the differences were significant when the colonoscope reached the splenic flexure as were the LF/HF balances at the splenic and hepatic flexures and the cecum. The percentage change in LF/HF was also analyzed, and it was found that in group 3 the mean change was over 136 % when the colonoscope reached the sigmoid flexure, which was significantly higher than in the other two groups. CONCLUSION: Most changes in HRV components occurred during colonoscopy of the left side of the bowel. Analgesia/sedation and total intravenous anesthesia increased HRV by increasing the LF component.

Adult↗

Effects of colonoscopy on intracranial pressure: observation in a large animal model.

BACKGROUND AND STUDY AIMS: Increased intra-abdominal pressure has been associated with increased intracranial pressure. Bowel insufflation during colonoscopy may increase the intra-abdominal pressure. It was hypothesized that colonoscopy may be associated with intracranial pressure elevation subsequent to an elevation in intra-abdominal pressure. MATERIALS AND METHODS: Colonoscopy was carried out in seven anesthetized pigs, and the colonoscope was advanced up to 60 cm from the anal verge. Insufflation was used to allow safe advancement of the colonoscope and to allow visualization of the colon, in the same way as in the procedure performed in humans. Intra-abdominal pressure was measured by determining the hydrostatic pressure in the urinary bladder. A subarachnoid screw was used to monitor intracranial pressure. The mean arterial blood pressure and intra-abdominal venous pressure were directly monitored via the femoral vessel access; all parameters were recorded before and during colonoscopy. RESULTS: A statistically significant elevation in intracranial pressure was demonstrated during colonoscopy. The average increase in intracranial pressure was 3.1 mm Hg. The intra-abdominal pressure and intra-abdominal venous pressure were also significantly elevated during the procedure. CONCLUSIONS: Colonoscopy may increase intracranial pressure due to an increase in intra-abdominal pressure. This may have clinical implications when colonoscopy is conducted in patients with brain pathology associated with high intracranial pressure.

Anesthesia, General↗

Ileocolonic lymphomas: a series of 16 cases.

BACKGROUND: Colonoscopic and clinical differences between primary ileocolonic mucosa-associated lymphoid tissue (MALT) lymphoma and mantle cell lymphoma (MCL) have not been defined. METHODS: We reviewed colonoscopic and clinical features in eight patients with primary MALT lymphoma and eight patients with MCL in the terminal ileum and/or colorectum. All cases were examined for CD5 and/or cyclin D1 expression. RESULTS: Endoscopic features of MALT lymphoma were characterized as protrusions that were covered with normal-appearing mucosa with or without ulceration. The gross appearances of MALT lymphomas were categorized as solitary (4 patients), multiple (3 patients), and multiple lymphomatous polyposis (MLP) (1 patient). The gross features of MCL at endoscopy were categorized as multiple protrusions (2 patients), and MLP (6 patients). The clinical stages of patients with MCL were more advanced than in patients with MALT lymphoma. CONCLUSIONS: Solitary or multiple protrusions at an early clinical stage is the most common presentation pattern of patients with MALT lymphoma, but an MLP appearance at an early stage is also possible. On the other hand, MLP appearance with an advanced clinical stage is the main presentation pattern in patients with MCL, although multiple protrusions with an early clinical stage is also possible. Histological and immunohistochemical investigation including that of cyclin D1 and CD5 expression is essential to make the final diagnosis.

Adult↗

Primary sclerosing cholangitis, inflammatory bowel disease, and colon cancer.

The prevalence of inflammatory bowel disease (IBD) in patients with PSC differs in various part of the world. Ulcerative colitis (UC) is most common, but 1 to 14% of all primary sclerosing cholangitis (PSC) patients have Crohn disease with colonic involvement. Many PSC patients without clinical symptoms of IBD have colonoscopic and histological findings compatible with IBD, and the subclinical phase may last several years before onset of symptoms of active colitis. The characteristics of UC in patients with PSC are different from those in UC patients without PSC. The colitis is usually substantial, the clinical course of the colitis is quiescent, and rectal sparing is common. Moreover, PSC patients with UC have a higher risk of developing colorectal dysplasia/carcinoma than UC patients without PSC. In patients having an ileal pelvic pouch with ileal anal anastomosis, PSC is a risk factor for development of pouchitis. It is important that all PSC patients with UC are included in colonoscopic surveillance programs.

Cholangitis, Sclerosing↗

High-magnification chromoscopic colonoscopy in ulcerative colitis: a valid tool for in vivo optical biopsy and assessment of disease extent.

BACKGROUND AND STUDY AIMS: Colonoscopy with mucosal biopsy is currently considered to be the "gold standard" investigation for the evaluation of disease activity and disease extent in ulcerative colitis. Conventional colonoscopic criteria are inadequate for assessing disease extent and for predicting clinical relapse, however. Histopathological markers of relapse, such as microscopic crypt abscess formation and mucin depletion cannot be identified using conventional endoscopy. The aim of this study was to evaluate the efficacy of high-magnification chromoscopic colonoscopy for the in vivo assessment of histopathological inflammation and disease extent using standardised endoscopic and histopathological criteria. PATIENTS AND METHODS: Total colonoscopy using the Olympus CF240Z magnifying colonoscope was performed prospectively in 325 consecutive patients with a known diagnosis of ulcerative colitis. A "biphasic" examination of all five colonic segments and the rectum was performed with conventional endoscopy followed by magnification imaging and biopsy. Disease activity was documented using Baron's classification, modified Saitoh criteria for magnification imaging, and Matts' histopathological grading. RESULTS: A total of 1800 images from 300 patients were analyzed (25 patients were excluded). The kappa coefficients of agreement between Saitoh's magnification criteria grades 1/2, 3/4, and 5/6 and Matts' histopathological grades 1/2, 3a/b, and 4/5 were 0.96, 0.62, and 0.51, respectively. Mild, moderate, and severe histopathological disease (Matts' grades 1/2, 3a - 4, and 5) were represented more accurately using Saitoh's criteria than by conventional Baron scores for all clinical parameters ( R = 0.976; P < 0.001). Magnification imaging was significantly better than conventional colonoscopy for predicting disease extent in vivo ( P < 0.0001). CONCLUSIONS: This is the largest prospective study and the only Western group to report on this application of magnification imaging. High-magnification imaging provides a sensitive and specific in vivo "virtual biopsy" in ulcerative colitis and so an instant biomarker for disease relapse, while accurately predicting disease extent. High-accuracy optical biopsy can limit the number of biopsies required, with significant cost savings for pathology services.

Adolescent↗

Anal sphincter defects in fecal incontinence: correlation between endosonography and surgery.

BACKGROUND AND STUDY AIMS: Endoscopic ultrasound provides accurate information about the anatomy of the anal sphincter. The purposes of this study were to evaluate the use of flexible echo endoscopes to examine the anal sphincters, to validate the diagnosis of internal and external sphincter defects obtained using echo endoscopes by comparison with surgical findings, and to assess the outcome after surgical sphincter repair. PATIENTS AND METHODS: Twenty-eight patients (13 women, 15 men, median age 50 years, range 30-83) with fecal incontinence--which was of traumatic origin in all but one (childbirth: n = 8; anorectal surgery: n = 17; biopsy of the prostate: n = 2; no trauma: n =1)--were prospectively investigated by endosonography using an echo colonoscope (n = 14) or an echo gastroscope (n = 14) (CF-UM20, GF-UM20, Olympus Optical). The location and extent of the defects of the internal or external sphincters, or both, were compared with the surgical findings in all patients. The surgical outcome was defined as excellent, improved, or unchanged. RESULTS: At surgery, 25 of the 28 patients had an isolated internal sphincter defect (n = 15) or combined sphincter defect (n = 10). Endoscopic ultrasound identified all of the external anal sphincter defects (n = 10), and correctly excluded a defect in 15 of 18 patients (sensitivity, specificity, and accuracy 100%, 83% and 89%, respectively). All of the internal sphincter defects (n = 25) were detected by endosonography. In three patients, a postulated intact internal sphincter was confirmed by surgery (accuracy 100%). In two patients, the extent of the sphincter defect was underestimated. Despite good visualization of the internal and external anal sphincters, as well as of the puborectal muscle in all patients, the shape, diameter, and full radial image sector (360 degrees) of the echo gastroscope made this instrument more practicable than the echo colonoscope. Nineteen of 25 patients who underwent surgery (76%) with proved sphincter defects experienced improvement, the figure reaching 87% (13 of 15) in patients who received isolated internal sphincter defect repair. CONCLUSIONS: Anal endosonography, even using flexible echo endoscopes, is an accurate method for identifying anal sphincter defects, and is the method of choice for preoperative sphincter mapping with special regard to internal sphincter repair, which can be carried out with excellent results.

Adult↗

Transcolonoscopic extraperitoneal cecostomy. A new therapeutic and technical proposal.

The authors propose a new technique of decompression of the colon consisting in percutaneous cecostomy with previous extraperitonization of the cecum under colonoscopic orientation. The technique permits decompression of the entire colon through the insertion of a ceco-anal multiperforated Levine tube on withdrawing the colonoscope. It is a new therapeutic choice for the treatment of the Ogilvie syndrome, toxic megacolon and other morbid entities, which may permit the performance of the procedure and require decompression of the colon, which proved to be extremely effective in the treatment of a patient with the Ogilvie syndrome.

Aged↗

Endoscopic removal of colonic lipoma.

A 71-year-old female with symptomatic colonic lipoma is described. An uneventful colonoscopic removal of the lipoma was performed. Colonoscopic removal of symptomatic pedunculated submucosal colonic lipoma may be recommended.

Aged↗

Neostigmine for the treatment of acute colonic pseudo-obstruction.

BACKGROUND: Acute colonic pseudo-obstruction -- that is, massive dilation of the colon without mechanical obstruction -- may develop after surgery or severe illness. Although it may resolve with conservative therapy, colonoscopic decompression is sometimes needed to prevent ischemia and perforation of the bowel. Uncontrolled studies have suggested that neostigmine, may be an effective treatment. METHODS: We studied 21 patients with acute colonic pseudo-obstruction. All had abdominal distention and radiographic evidence of colonic dilation, with a cecal diameter of at least 10 cm, and had had no response to at least 24 hours of conservative treatment. We randomly assigned 11 to receive 2.0 mg of neostigmine intravenously and 10 to receive intravenous saline. A physician who was unaware of the patients' treatment assignments recorded clinical response (defined as prompt evacuation of flatus or stool and a reduction in abdominal distention), abdominal circumference, and measurements of the colon on radiographs. Patients who had no response to the initial injection were eligible to receive open-label neostigmine three hours later. RESULTS: Ten of the 11 patients who received neostigmine had prompt colonic decompression, as compared with none of the 10 patients who received placebo (P<0.001). The median time to response was 4 minutes (range, 3 to 30). Seven patients in the placebo group and the one patient in the neostigmine group without an initial response received open-label neostigmine; all had colonic decompression. Two patients who had an initial response to neostigmine required colonoscopic decompression for recurrence of colonic distention; one eventually underwent subtotal colectomy. Side effects of neostigmine included abdominal pain, excess salivation, and vomiting. Symptomatic bradycardia developed in two patients and was treated with atropine. CONCLUSIONS: In patients with acute colonic pseudo-obstruction who have not had a response to conservative therapy, treatment with neostigmine rapidly decompresses the colon.

Abdominal Pain↗

Urgent colonoscopy for the diagnosis and treatment of severe diverticular hemorrhage.

BACKGROUND: Although endoscopy is often used to diagnose and treat acute upper gastrointestinal bleeding, its role in the management of diverticulosis and lower gastrointestinal bleeding is uncertain. METHODS: We studied the role of urgent colonoscopy in the diagnosis and treatment of 121 patients with severe hematochezia and diverticulosis. All patients were hospitalized, received blood transfusions as needed, and received a purge to rid the colon of clots, stool, and blood. Colonoscopy was performed within 6 to 12 hours after hospitalization or the diagnosis of hematochezia. Among the first 73 patients, those with continued diverticular bleeding underwent hemicolectomy. For the subsequent 48 patients, those requiring treatment received therapy, such as epinephrine injections or bipolar coagulation, through the colonoscope. RESULTS: Of the first 73 patients, 17 (23 percent) had definite signs of diverticular hemorrhage (active bleeding in 6, nonbleeding visible vessels in 4, and adherent clots in 7). Nine of the 17 had additional bleeding after colonoscopy, and 6 of these required hemicolectomy. Of the subsequent 48 patients, 10 (21 percent) had definite signs of diverticular hemorrhage (active bleeding in 5, nonbleeding visible vessels in 2, and adherent clots in 3). An additional 14 patients in this group (29 percent) were presumed to have diverticular bleeding because although they had no stigmata of diverticular hemorrhage, no other source of bleeding was identified. The other 24 patients (50 percent) had other identified sources of bleeding. All 10 patients with definite diverticular hemorrhage were treated endoscopically; none had recurrent bleeding or required surgery. CONCLUSIONS: Among patients with severe hematochezia and diverticulosis, at least one fifth have definite diverticular hemorrhage. Colonoscopic treatment of such patients with epinephrine injections, bipolar coagulation, or both may prevent recurrent bleeding and decrease the need for surgery.

Acute Disease↗

Use of colonoscopy to screen asymptomatic adults for colorectal cancer. Veterans Affairs Cooperative Study Group 380.

BACKGROUND AND METHODS: The role of colonoscopy in screening for colorectal cancer is uncertain. At 13 Veterans Affairs Medical Centers, we performed colonoscopy to determine the prevalence and location of advanced colonic neoplasms and the risk of advanced proximal neoplasia in asymptomatic patients (age range, 50 to 75 years) with or without distal neoplasia. Advanced colonic neoplasia was defined as an adenoma that was 10 mm or more in diameter, a villous adenoma, an adenoma with high-grade dysplasia, or invasive cancer. In patients with more than one neoplastic lesion, classification was based on the most advanced lesion. RESULTS: Of 17,732 patients screened for enrollment, 3196 were enrolled; 3121 of the enrolled patients (97.7 percent) underwent complete examination of the colon. The mean age of the patients was 62.9 years, and 96.8 percent were men. Colonoscopic examination showed one or more neoplastic lesions in 37.5 percent of the patients, an adenoma with a diameter of at least 10 mm or a villous adenoma in 7.9 percent, an adenoma with high-grade dysplasia in 1.6 percent, and invasive cancer in 1.0 percent. Of the 1765 patients with no polyps in the portion of the colon that was distal to the splenic flexure, 48 (2.7 percent) had advanced proximal neoplasms. Patients with large adenomas (> or = 10 mm) or small adenomas (< 10 mm) in the distal colon were more likely to have advanced proximal neoplasia than were patients with no distal adenomas (odds ratios, 3.4 [95 percent confidence interval, 1.8 to 6.5] and 2.6 (95 percent confidence interval, 1.7 to 4.1], respectively). However, 52 percent of the 128 patients with advanced proximal neoplasia had no distal adenomas. CONCLUSIONS: Colonoscopic screening can detect advanced colonic neoplasms in asymptomatic adults. Many of these neoplasms would not be detected with sigmoidoscopy.

Adenoma↗

Risk of advanced proximal neoplasms in asymptomatic adults according to the distal colorectal findings.

BACKGROUND AND METHODS: The clinical significance of a distal colorectal polyp is uncertain. We determined the risk of advanced proximal neoplasia, defined as a polyp with villous features, a polyp with high-grade dysplasia, or cancer, among persons with distal hyperplastic or neoplastic polyps as compared with the risk among persons with no distal polyps. We analyzed data from 1994 consecutive asymptomatic adults (age, 50 years or older) who underwent colonoscopic screening for the first time between September 1995 and December 1998 as part of a program sponsored by an employer. The location and histologic features of all polyps were recorded. Colonoscopy to the level of the cecum was completed in 97.0 percent of the patients. RESULTS: Sixty-one patients (3.1 percent) had advanced lesions in the distal colon, including 5 with cancer, and 50 (2.5 percent) had advanced proximal lesions, including 7 with cancer. Twenty-three patients with advanced proximal neoplasms (46 percent) had no distal polyps. The prevalence of advanced proximal neoplasia among patients with no distal polyps was 1.5 percent (23 cases among 1564 persons; 95 percent confidence interval, 0.9 to 2.1 percent). Among patients with distal hyperplastic polyps, those with distal tubular adenomas, and those with advanced distal polyps, the prevalence of advanced proximal neoplasia was 4.0 percent (8 cases among 201 patients), 7.1 percent (12 cases among 168 patients), and 11.5 percent (7 cases among 61 patients), respectively. The relative risk of advanced proximal neoplasia, adjusted for age and sex, was 2.6 for patients with distal hyperplastic polyps, 4.0 for those with distal tubular adenomas, and 6.7 for those with advanced distal polyps, as compared with patients who had no distal polyps. Older age and male sex were associated with an increased risk of advanced proximal neoplasia (relative risk, 1.3 for every five years of age and 3.3 for male sex). CONCLUSIONS: Asymptomatic persons 50 years of age or older who have polyps in the distal colon are more likely to have advanced proximal neoplasia than are persons without distal polyps. However, if colonoscopic screening is performed only in persons with distal polyps, about half the cases of advanced proximal neoplasia will not be detected.

Adenoma↗