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At least 19 recordsLinked to original sources
PubMed2000

A randomized, controlled trial to assess a novel colorectal cancer screening strategy: the conversion strategy--a comparison of sequential sigmoidoscopy and colonoscopy with immediate conversion from sigmoidoscopy to colonoscopy in patients with an abnormal screening sigmoidoscopy.

OBJECTIVE: Our study was a randomized, controlled trial to assess a novel strategy that provides comprehensive colorectal cancer screening in a single visit versus traditional sigmoidoscopy and, where appropriate, colonoscopy on a subsequent day. METHODS: Consecutive patients referred for screening were randomized to control or so-called "conversion" groups. Patients in the control group were prepared for sigmoidoscopy with oral phospho-soda. Those with an abnormal sigmoidoscopy were scheduled for colonoscopy on a future day after oral polyethylene glycol preparation. In the conversion group, patients were prepared with oral phosphosoda. Patients with a polyp >5 mm or multiple diminutive polyps were converted from sigmoidoscopy to colonoscopy, allowing comprehensive screening in a single visit. Clinical outcomes were assessed by postprocedure physician and patient questionnaires. RESULTS: Two hundred thirty-five patients were randomized (control = 121, conversion = 114). In the control group, 28% had an indication for colonoscopy. Three of 33 (9%) with an abnormal sigmoidoscopy did not return for colonoscopy. At colonoscopy, 27% had a proximal adenoma. In the conversion group, 28% had an abnormal sigmoidoscopy and underwent conversion to colonoscopy. Forty-one percent undergoing colonoscopy in the conversion group had a proximal adenoma. Physicians reported no differences in preparation or procedure difficulty, whereas patients reported no differences in the level of comfort or overall satisfaction between groups. When queried regarding preferences for future screening, 96% chose the conversion strategy. CONCLUSIONS: The conversion strategy led to similar outcomes compared to traditional screening while improving compliance with colonoscopy in patients with an abnormal sigmoidoscopy.

Adenoma↗
PubMed1994

Relationship between flexible sigmoidoscopy training during residency and subsequent sigmoidoscopy performance in practice.

BACKGROUND: The primary objective of the research was to determine whether sigmoidoscopy training during family practice residency is associated with subsequent performance of sigmoidoscopy in practice. METHODS: We surveyed 292 family physicians who graduated from the University of Minnesota Department of Family Practice and Community Health residency program between 1983 and 1989. The survey instrument collected information on the number of physicians who were currently performing flexible sigmoidoscopy in their practices and what factors were associated with performance of this procedure. RESULTS: Physicians with flexible sigmoidoscopy training during residency were performing flexible sigmoidoscopies at a significantly higher rate than those without training during residency (P = .001). A significantly higher proportion of males were performing flexible sigmoidoscopy in their practices than females (P = .0002). The mean number of flexible sigmoidoscopies recommended by residency-trained physicians to be performed during residency for adequate training was 16. CONCLUSIONS: Training in flexible sigmoidoscopy during a family practice residency is associated with a higher rate of flexible sigmoidoscopy performance later in practice. Female physicians perform flexible sigmoidoscopy at a significantly lower rate than their male colleagues; this could be due to a less-adequate training during residency. We recommend that residents perform a minimum of 16 flexible sigmoidoscopies during residency training.

Adult↗
PubMed1987

Patient response to sigmoidoscopy. A randomized, controlled trial of rigid and flexible sigmoidoscopy.

Sigmoidoscopy could aid in the control of large bowel cancer by early detection of the 55% of colorectal cancers that develop in the rectosigmoid and by the identification and eradication of significant rectosigmoid adenomas. Rigid sigmoidoscopy has had poor patient acceptance and therefore has not been successful. The present study is a prospective randomized trial to evaluate patient response to flexible as compared with rigid sigmoidoscopy. Patients reported significantly less discomfort (10.1% versus 29.7%), anxiety (9.8% versus 27.6%) and embarrassment (5.2% versus 12.8%) during flexible as compared with rigid sigmoidoscopy. Flexible sigmoidoscopy appears to have better patient acceptance than rigid sigmoidoscopy (P less than 0.01). This could enhance its value as a cancer-control instrument. This article addresses the feasibility of sigmoidoscopy. Its validity also needs to be addressed within the framework of a long-term trial, evaluating mortality for rectosigmoid cancer.

Clinical Trials as Topic↗
PubMed2002

Synchronous proximal polyps and cancer in patients with polyps detected at sigmoidoscopy: results of a single, rural-based sigmoidoscopy clinic.

The prevalence of polyps and cancer in the proximal colon among patients who have polyps detected on sigmoidoscopy was determined in a large rural referral hospital in north central Pennsylvania. Eleven thousand one hundred sixty patients underwent sigmoidoscopy between 1991 and 1997. Polyps were detected in 709 patients. Five hundred twenty-three patients who had a polyp at sigmoidoscopy and full colonoscopy completed within one year were included in this study. 120 patients (23%) had a proximal polyp detected at colonoscopy. The prevalence of proximal polyps and histologically advanced polyps was related to the size, number, and histology of the distal index polyp found at sigmoidoscopy. However, the absolute difference in prevalence of proximal polyps stratified by dings at sigmoidoscopy was small. A total of 5 adenocarcinomas were detected in the proximal colon. All proximal cancers detected at colonoscopy occurred in patients with a distal polyp less than 10 mm. Our data emphasize the importance of colonoscopy in all patients with a polyp detected at sigmoidoscopy independent of its size and histology.

Adenocarcinoma↗
PubMedDate not supplied

The role of sigmoidoscopy for asymptomatic patients. Results of three annual screening sigmoidoscopies, polypectomy, and subsequent surveillance colonoscopy in a primary-care setting.

A total of 329 asymptomatic patients (aged 50 or older) underwent flexible sigmoidoscopy to screen for colonic neoplasia. Of these, 258 underwent a second examination after 1 year and 143 underwent a third examination after another year. Of 60 patients in whom polyps were found on one of the three examinations, 58 underwent colonoscopy and polypectomy; 77 adenomatous polyps were present in 39 of these patients. The incidence of adenomatous polyps was 7.9% for the first examination, 3.9% for the second, and 2.1% for the third. Of patients with an index polyp found by sigmoidoscopy, 57.5% had synchronous polyps discovered by colonoscopy. Thirty-six of 77 polyps in 24 patients showed dysplasia; 9 were less than 0.5 cm, 14 were 0.5 cm to 0.9 cm, and 13 were 1 cm or larger. Forty-four surveillance colonoscopies (done after initial colonoscopy and polypectomy) have been performed in 28 patients. Eighteen examinations resulted in finding 30 adenomatous polyps, of which 10 showed dysplasia. This study 1) is the first report of flexible sigmoidoscopy data to support the American Cancer Society recommendation of two serial screening sigmoidoscopies a year apart, 2) reinforces the concept that an index polyp indicates a need for a complete colonoscopy, 3) reinforces the need for ongoing surveillance by colonoscopy after detection of adenomas, and 4) adds to reports of dysplasia in diminutive polyps.

Aged↗
PubMed1984

Why flexible sigmoidoscopy instead of rigid sigmoidoscopy?

Representative outcome studies describing the procedures of rigid sigmoidoscopy and use of the 60-cm flexible sigmoidoscope are summarized. Subspecialist outcomes are compared with those obtained by family physicians. Family physicians consistently obtain similar insertion depths and diagnostic yields, although comparison is difficult because of referral bias and inconsistency regarding the reporting of hyperplastic polyps. No complications have been reported to date. Low physician and patient compliance with suggested guidelines for sigmoidoscopic examination may be partially responsible for unchanged five-year survival rates for colorectal cancer over the last 30 years. Preliminary studies indicate that the 60-cm flexible sigmoidoscope has improved compliance in at least one setting. Longitudinal cost-benefit studies should be performed in primary care settings.

Clinical Competence↗
PubMed1996

A study at 10 medical centers of the safety and efficacy of 48 flexible sigmoidoscopies and 8 colonoscopies during pregnancy with follow-up of fetal outcome and with comparison to control groups.

To analyze the risks versus benefits of flexible sigmoidoscopy and colonoscopy to the pregnant female and fetus, we conducted a multiyear, retrospective study at 10 hospitals of 46 patients undergoing 48 sigmoidoscopies and 8 patients undergoing 8 colonoscopies during pregnancy. Sigmoidoscopy controls included two study control groups and the average American pregnancy outcomes. Sigmoidoscopy indications included hematochezia in 28, diarrhea in 10, abdominal pain in 4, and other in 3. Thirteen patients were in the first trimester of pregnancy, 18 were in the second trimester, and 15 were in the third trimester. Twenty-seven patients had a lesion diagnosed by sigmoidoscopy, including reactivated or newly diagnosed inflammatory bowel disease, bleeding internal hemorrhoids, and other colitidies. Twenty-two of 29 patients with rectal bleeding had a significant lesion identified by sigmoidoscopy. Sigmoidoscopy was significantly more frequently diagnostic for hematochezia than for other indications (p < 0.03, chi2). No endoscopic complications occurred to the pregnant patients. Excluding 4 voluntary abortions and 1 unknown pregnancy outcome, 38 (93%) of 41 pregnant females delivered healthy babies (study control rate = 93%; NS, Fisher's exact test). Mean live-born infant Apgar scores were 8.2+/-1.5 (SD) at 1 min and 9.0+/-0.2 at 5 min (control mean Apgar scores: 8.1+/-1.7 at 1 min and 8.8+/-1.0 at 5 min; NS, Student's t test). Three high-risk pregnancies ended with fetal demise at 8, 9, or 12 weeks after sigmoidoscopy, from causes unrelated to sigmoidoscopy. No fetal cardiac abnormalities were detected by fetal cardiac monitoring during two sigmoidoscopies. Eight pregnant females underwent colonoscopy, without complications. Pregnancy outcomes included six healthy babies delivered at full term, one voluntary abortion, and one fetal demise in a high-risk pregnancy 4 months after colonoscopy from causes unrelated to colonoscopy. This study suggests that sigmoidoscopy does not induce labor or result in congenital malformations, that sigmoidoscopy is not contraindicated during pregnancy, and that sigmoidoscopy may be beneficial in pregnant patients with significant lower gastrointestinal bleeding. Colonoscopy during pregnancy should be considered for life-threatening lower gastrointestinal bleeding or when the only alternative is surgery.

Colonoscopy↗
PubMed2000

Flexible sigmoidoscopy training and its impact on colorectal cancer screening by primary care physicians.

BACKGROUND: Colorectal cancer is an ideal disease for prevention with screening programs. Efforts to increase compliance with screening recommendations have included training primary care physicians to perform flexible sigmoidoscopy. OBJECTIVE: To assess the impact of flexible sigmoidoscopy training on compliance with current screening recommendations. METHODS: We performed a cross-sectional study of 232 patients cared for by physicians in a primary care network. MAIN OUTCOME MEASURES: Rates of screening for colorectal cancer and rates of undergoing flexible sigmoidoscopy were compared across patient groups according to the physician's training and whether the physician performs flexible sigmoidoscopy in his or her practice. RESULTS: Among 217 patients included in the analysis, 122 (56%) were cared for by physicians who were trained in flexible sigmoidoscopy, of whom 79 (36%) were cared for by physicians who perform flexible sigmoidoscopy in their practice. Patients cared for by physicians trained in flexible sigmoidoscopy were not significantly more likely to receive any colorectal cancer screening than were patients cared for by physicians not trained in flexible sigmoidoscopy (odds ratio, 1.16; 95% confidence interval, 0.67-2.01). However, patients cared for by physicians who perform flexible sigmoidoscopy in their practice were more likely to have undergone any colorectal cancer screening (odds ratio, 1.73; 95% confidence interval, 1.02-2.95) and flexible sigmoidoscopy (odds ratio, 2.69; 95% confidence interval, 1.14-6.36). CONCLUSION: Performance of flexible sigmoidoscopy by primary care physicians has the potential to increase the rate of colorectal cancer screening with flexible sigmoidoscopy.

Aged↗
PubMed1995

Multicenter, multiyear study of safety and efficacy of flexible sigmoidoscopy during pregnancy in 24 females with follow-up of fetal outcome.

Our objectives were to analyze the risks versus benefits of flexible sigmoidoscopy to the pregnant female and fetus. We retrospectively studied 24 consecutive pregnant patients admitted to four university hospitals during seven years who underwent 26 flexible sigmoidoscopies. Sigmoidoscopy indications included hematochezia in 11, diarrhea in 12, abdominal pain in 7, constipation in 2, and occult rectal bleeding in 1. Seven patients were in the first trimester of pregnancy, nine were in the second trimester, and eight were in the third trimester. Sigmoidoscopy provided helpful clinical information in all patients. Twelve patients had a lesion diagnosed by sigmoidoscopy, including reactivation of Crohn's colitis, reactivation of ulcerative colitis, infectious colitis, nonspecific colitis, bleeding internal hemorrhoids, pseudomembranous colitis, anastomotic ulcer, and newly diagnosed Crohn's colitis. In particular, nine of 11 patients with rectal bleeding had a lesion identified by sigmoidoscopy. No endoscopic complications occurred to any pregnant female. Two pregnant patients underwent repeat sigmoidoscopy without complications. Fetal outcome was ascertained in all but one pregnancy. Eighteen pregnant females delivered healthy infants (16 at full term, two at 35 or 36 weeks). Their mean Apgar scores were 8.8 +/- 0.4 SD at 1 min, and 9.0 +/- 0.4 SD at 5 min. One diabetic and hypertensive female suffered an involuntary abortion nine weeks after sigmoidoscopy, which appeared unrelated to the sigmoidoscopy. Four pregnancies were voluntarily aborted. This study suggests that flexible sigmoidoscopy does not induce labor or result in congenital malformations, that sigmoidoscopy is not contraindicated during pregnancy, and that sigmoidoscopy should be considered in medically stable pregnant patients with significant gastrointestinal bleeding.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1979

Comparison of flexible sigmoidoscopy with other diagnostic techniques in the diagnosis of rectocolon neoplasia.

Flexible sigmoidoscopy was compared to rigid sigmoidoscopy in the detection of colorectal neoplasia in a select group of patients. A distance of 30 cm or greater was obtained by flexible sigmoidoscopy in 94% of patients and a distance of 50 cm or greater in 46% of patients. A significant number of cancers and adenomas detected by flexible sigmoidoscopy were not detected by rigid sigmoidoscopy. Flexible sigmoidoscopy was tolerated better than rigid sigmoidoscopy but required twice the time. Flexible sigmoidoscopy could be combined with air-contrast barium enema the same day with the one preparation and did not interfere with the x-ray examination. All cancers and a significant number of adenomas detected subsequently on colonoscopy were detected by the combination of flexible sigmoidoscopy and air-contrast barium enema. Although the combination of flexible sigmoidoscopy and air-contrast barium enema is not adequate for thorough diagnostic evaluation of patients with a positive screening test, it may be of value in other select clinical situations. Flexible sigmoidoscopy has the potential for higher yield and better patient tolerance as compared to rigid sigmoidoscopy. This warrants further evaluation.

Adenoma↗
PubMed1999

Primary care physicians' decisions to perform flexible sigmoidoscopy.

OBJECTIVE: This study was designed to identify factors that influence primary care physicians' willingness to perform flexible sigmoidoscopy. MEASUREMENTS: Using a mailed questionnaire, we surveyed all 161 primary care physicians participating in a large health care system. We obtained information on training, current practice patterns, beliefs about screening for colorectal cancer, and the influence of various factors on their decision whether or not to perform flexible sigmoidoscopy in practice. MAIN RESULTS: Of the 131 physicians included in the analysis, 68 (52%) reported training in flexible sigmoidoscopy, of whom 36 (53%) were currently performing flexible sigmoidoscopy in practice. Time required to perform flexible sigmoidoscopy, availability of adequately trained staff, and availability of flexible sigmoidoscopy services provided by other clinicians were identified most often as reasons not to perform the procedure in practice. Male physicians were more likely than female physicians to report either performing flexible sigmoidoscopy or desiring to train to perform flexible sigmoidoscopy (odds ratio 2.61; 95% confidence interval 1.10, 6.23). This observed difference appears to be mediated through different weighting of decision criteria by male and female physicians. CONCLUSIONS: Approximately half of these primary care physicians trained in flexible sigmoidoscopy chose not to perform this procedure in practice. Self-perceived inefficiency in performing office-based flexible sigmoidoscopy deterred many of these physicians from providing this service for their patients.

Adult↗
PubMed2002

Adherence to repeat screening flexible sigmoidoscopy in the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial.

BACKGROUND: Acceptance of screening flexible sigmoidoscopy has been poor, in part because of providers' concerns regarding the acceptability of the procedure. In the current prospective study, the authors used adherence to repeat testing to assess the acceptability of screening flexible sigmoidoscopy. METHODS: The current study was a prospective study of a randomized clinical trial drawing volunteers from the community. Subjects included 10,164 Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial participants who were available for follow-up 3 years after undergoing a baseline screening flexible sigmoidoscopy examination. The authors measured adherence and identified those factors that appeared to affect adherence to repeat sigmoidoscopy. RESULTS: Overall, 18.3% of women and 10.0% of men did not undergo a repeat sigmoidoscopy. Among individuals who attended the Year-3 clinic, 10.4% of women and 5.1% of men specifically refused repeat sigmoidoscopy when it was offered (risk of refusal in women compared with men, 2.04; 95% confidence interval, 1.76-2.36). Another factor found to be associated with refusal included a technically inadequate baseline sigmoidoscopy. CONCLUSIONS: Gender and past experiences with sigmoidoscopy may impact adherence to repeat screening. Nonetheless, among research volunteers in a randomized clinical trial of screening, excellent adherence to repeat screening flexible sigmoidoscopy could be achieved.

Aged↗
PubMed1994

Safety and clinical efficacy of flexible sigmoidoscopy and colonoscopy for gastrointestinal bleeding after myocardial infarction. A six-year study of 18 consecutive lower endoscopies at two university teaching hospitals.

The risks versus benefits of flexible sigmoidoscopy and colonoscopy performed within three weeks of myocardial infarction were studied in nine consecutive patients who underwent sigmoidoscopy and in nine consecutive patients who underwent colonoscopy at two university hospitals. Indications for sigmoidoscopy were red blood per rectum in seven and occult blood in the stools in two. Sigmoidoscopy provided the diagnosis in three, including colon cancer in two and bleeding internal hemorrhoids in one, and provided helpful information in three. Sigmoidoscopy led to colon cancer surgery in two patients, and polypectomy of a 1-cm adenoma in one. Of two highly unstable patients before sigmoidoscopy, one developed second-degree heart block and frequent premature ventricular contractions 3 hr after sigmoidoscopy. No sigmoidoscopic complications occurred in the seven relatively clinically stable patients. Indications for colonoscopy included red blood per rectum in five, occult blood in the stools in three, and melena in one. Colonoscopy provided the diagnosis in five, including one each with colon cancer, internal hemorrhoids, large adenoma, ischemic colitis, and angiodysplasia. Colonoscopy resulted in colon cancer surgery in one patient and endoscopic polypectomies in three patients. Of two moderately unstable patients before colonoscopy, one developed asymptomatic bradycardia during colonoscopy. No colonoscopic complications occurred in the seven clinically stable patients. This study suggests that recent myocardial infarction is not an absolute contraindication to sigmoidoscopy or colonoscopy, that sigmoidoscopy is beneficial in medically stable patients with significant gastrointestinal bleeding, and that colonoscopy may be beneficial in selected, highly stable patients with significant gastrointestinal bleeding.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1993

Screening flexible sigmoidoscopy: patient attitudes and compliance.

OBJECTIVE: To measure patients' expectations and attitudes about screening flexible sigmoidoscopy and their discomfort during the procedure, and to identify factors affecting compliance among patients scheduled for sigmoidoscopy. DESIGN: Patient survey at the time sigmoidoscopy was ordered and again one week after the procedure was performed. SETTING: An academic general internal medicine practice. PATIENTS: 105 consecutive patients scheduled for screening flexible sigmoidoscopy. MAIN RESULTS: Seventy-five percent of patients (79/105) scheduled for sigmoidoscopy complied with the procedure. Compliance was higher among men and among patients who had family histories of colon cancer. Although many patients experienced moderate to extreme embarrassment (27%), discomfort (42%), and pain (31%), patients experienced less embarrassment (p = 0.03) and pain (p = 0.02) than they had expected. Patients aged 65 years and older were twice as likely as younger ones (52% versus 25%) to experience moderate to extreme pain (p = 0.04). Only 1.4% of patients reported that they would probably not have the test again. CONCLUSION: Although flexible sigmoidoscopy is an uncomfortable procedure for some patients, especially those aged 65 and older, in general it is not as bad as patients expect and most would have the test again. Therefore, rather than assuming sigmoidoscopy is too uncomfortable for all patients to tolerate as a screening test, clinicians should inform their patients about the potential benefits and risks of sigmoidoscopy and about what the patient can expect during the procedure, thus enabling the patient to make an informed decision about whether to undergo screening sigmoidoscopy.

Aged↗
PubMed2000

The utilization of flexible sigmoidoscopy by family practitioners after residency training.

BACKGROUND: Flexible sigmoidoscopy is routinely performed by family practice physicians, most of whom receive training in postgraduate education programs. The aim of this study was to assess the utilization of flexible sigmoidoscopy by family practitioners who received training during residency. METHODS: Family practitioners who underwent training in flexible sigmoidoscopy during their residency were contacted by phone or mail and polled regarding their current use of flexible sigmoidoscopy and assessment of their previous training. RESULTS: Forty-two graduates were contacted; 76% were certified (according to our predefined criteria) during training and 74% were currently performing flexible sigmoidoscopy. Of those who were certified, 87% were currently using flexible sigmoidoscopy compared with 45% of those who did not receive certification (p = 0.02). Training during the last year of residency was more likely to be associated with current use of flexible sigmoidoscopy than earlier training (69% vs. 30%, p = 0.03). Certification was associated with more procedures during training (24.3 +/- 1.7 vs. 16.6 +/- 3.1, p < 0.05). Current users performed a mean of 4.3 +/- 0.75 procedures/month; most reached 40 cm in depth of insertion and completed the procedure in 17.2 +/- 1.2 minutes. Of patients undergoing flexible sigmoidoscopy, 13% were ultimately referred for colonoscopy. Most practitioners considered their training useful and only 9.6% had obtained additional training outside residency. CONCLUSIONS: Most family practitioners certified in flexible sigmoidoscopy during residency performed the procedure in their practices. Depth of insertion and time for completion of the procedure seem to be adequate.

Adult↗
PubMed1996

Sigmoidoscopy and rectal biopsy: a survey of current UK practice.

OBJECTIVE: To establish the pattern of practice of sigmoidoscopy and rectal biopsy in the UK, and to estimate the rate of occurrence of important complications. DESIGN: Postal questionnaire enquiring about practice in the previous 2 years. SUBJECTS: Consultant members of the British Society of Gastroenterology. MAIN OUTCOME MEASURES: Bleeding or perforation following sigmoidoscopy and rectal biopsy. RESULTS: Completed replies were received from 277 consultants, giving a response rate of 84%. Of the sigmoidoscopies performed, 71% were rigid and the remainder fibreoptic flexible sigmoidoscopy (FOS). The complication rate after sigmoidoscopy and rectal biopsy was 0.01%. Perforation was significantly more common in FOS than in rigid sigmoidoscopy (eight in 134,482 sigmoidoscopies versus five in 328,815, chi2 = 5.18, P < 0.05). The distance from anal margin and wall of biopsy did not influence perforation rates. Significant bleeding was similar with both techniques (eight in 134,482 versus 35 in 328,815, chi2 = 2.27, NS). CONCLUSION: Rigid sigmoidoscopy is still more widely used than FOS in the UK, and is probably safer. Complications resulting from rectal biopsy are uncommon but perforation occurs more frequently with FOS than with rigid sigmoidoscopy. The site of biopsy appears to be unimportant.

Biopsy↗
PubMed1998

Is colonoscopy indicated for small adenomas found by screening flexible sigmoidoscopy?

BACKGROUND: There is controversy over whether patients who have a small tubular adenoma on screening flexible sigmoidoscopy should undergo colonoscopic examination of the proximal colon. OBJECTIVE: To prospectively determine the prevalence of advanced polyps in the proximal colon among patients who have small adenomas on screening sigmoidoscopy. DESIGN: Prospective cohort study. SETTING: A health maintenance organization and a Veterans Affairs medical center. PATIENTS: Asymptomatic patients older than 50 years of age who had no risk factors for colon cancer and underwent sigmoidoscopy. INTERVENTION: At the time of sigmoidoscopy, all polyps were biopsied and characterized. All patients with distal adenomas were offered colonoscopy. MEASUREMENTS: The size and histology of polyps identified by sigmoidoscopy and colonoscopy were noted. Polyps were considered advanced if they were larger than 10 mm or were tubulovillous, villous, or malignant. The prevalence of advanced proximal polyps was determined, and patients were stratified by the size and number of distal polyps found by sigmoidoscopy. RESULTS: Among 4490 patients who underwent sigmoidoscopy, a neoplastic lesion was detected in 401 (8.9%) and colonoscopy was done in 301 (75%). Of 90 patients with a single tubular adenoma 1 to 5 mm in diameter in the distal colon, 0% (95% CI, 0.0% to 4.0%) had an advanced proximal polyp compared with 5.4% (CI, 2.4% to 10.4%) of those who had multiple distal polyps 1 to 5 mm or 6 to 10 mm in diameter and 7.9% (CI, 2.6% to 17.6%) of those who had advanced distal polyps (P = 0.013 for trend). The low-risk group with a single tubular adenoma 1 to 5 mm in diameter represented 44% of all patients with distal adenomas or cancers found at flexible sigmoidoscopy. CONCLUSIONS: Among patients undergoing screening sigmoidoscopy, those with single tubular adenomas of 5 mm or less had a low prevalence of advanced proximal polyps. These patients may not benefit from colonoscopy.

Adenoma↗