Serrated lesions of the colorectum: review and recommendations from an expert panel

Serrated lesions of the colorectum are the precursors of perhaps one-third of colorectal cancers (CRCs). Cancers arising in serrated lesions are usually in the proximal colon, and account for a disproportionate fraction of cancer identified after colonoscopy. We sought to provide guidance for the clinical management of serrated colorectal lesions based on current evidence and expert opinion regarding definitions, classification, and significance of serrated lesions. A consensus conference was held over 2 days reviewing the topic of serrated lesions from the perspectives of histology, molecular biology, epidemiology, clinical aspects, and serrated polyposis. Serrated lesions should be classified pathologically according to the World Health Organization criteria as hyperplastic polyp, sessile serrated adenoma/polyp (SSA/P) with or without cytological dysplasia, or traditional serrated adenoma (TSA). SSA/P and TSA are premalignant lesions, but SSA/P is the principal serrated precursor of CRCs. Serrated lesions have a distinct endoscopic appearance, and several lines of evidence suggest that on average they are more difficult to detect than conventional adenomatous polyps. Effective colonoscopy requires an endoscopist trained in the endoscopic appearance of serrated lesions. We recommend that all serrated lesions proximal to the sigmoid colon and all serrated lesions in the rectosigmoid > 5 mm in size, be completely removed. Recommendations are made for post-polypectomy surveillance of serrated lesions and for surveillance of serrated polyposis patients and their relatives.

Prevalence and variable detection of proximal colon serrated polyps during screening colonoscopy

BACKGROUND & AIMS

Colonoscopy may have a greater protective effect for distal colorectal cancer (CRC) than proximal CRC. Serrated polyps are frequently located in the proximal colon, can be missed during colonoscopy, and may progress to CRC. We investigated the prevalence and endoscopist detection rates of proximal serrated polyps in a large cohort of average risk patients undergoing screening colonoscopy.

METHODS

Screening colonoscopies performed by 15 attending gastroenterologists at 2 academic endoscopy units between 2000 and 2009 were reviewed. Serrated polyps included hyperplastic polyps, sessile serrated adenomas, and traditional serrated adenomas. Endoscopist-level detection rates for adenomas and serrated polyps were calculated. Pearson correlation coefficients were calculated to evaluate the associations of adenoma and proximal serrated polyp detection rates. Logistic regression was used to compare endoscopists' detection rates.

RESULTS

A total of 11,049 polyps were detected in 6681 colonoscopies (adenomas: 5637, 51%; serrated: 3984, 36%; proximal serrated: 1238, 11%). The proportion of colonoscopies with at least one proximal serrated polyp was 13% (range 1%-18%). Proximal serrated polyp detection rates per colonoscopy ranged from 0.01 to 0.26. Adenoma and proximal serrated polyp detection rates per colonoscopy were strongly correlated (R = 0.76, P = .0005). The odds of detecting at least one proximal serrated polyp for individual endoscopists ranged from 0.05 to 0.67 compared to the highest level detector. Endoscopist (P < .0001), but not patient age (P = .76) or gender (P = .95), was associated with proximal serrated polyp detection.

CONCLUSIONS

In an average-risk screening cohort, the detection of proximal serrated polyps was highly variable and endoscopist dependent. A significant proportion of proximal serrated polyps may be missed during colonoscopy. High-quality colonoscopy is important for the detection and resection of all polyps with neoplastic potential.

Guidelines for colonoscopy surveillance after cancer resection: a consensus update by the American Cancer Society and the US Multi-Society Task Force on Colorectal Cancer

Patients with resected colorectal cancer are at risk for recurrent cancer and metachronous neoplasms in the colon. This joint update of guidelines by the American Cancer Society and the US Multi-Society Task Force on Colorectal Cancer addresses only the use of endoscopy in the surveillance of these patients. Patients with endoscopically resected Stage I colorectal cancer, surgically resected Stages II and III cancers, and Stage IV cancer resected for cure (isolated hepatic or pulmonary metastasis) are candidates for endoscopic surveillance. The colorectum should be carefully cleared of synchronous neoplasia in the perioperative period. In nonobstructed colons, colonoscopy should be performed preoperatively. In obstructed colons, double-contrast barium enema or computed tomography colonography should be performed preoperatively, and colonoscopy should be performed 3 to 6 months after surgery. These steps complete the process of clearing synchronous disease. After clearing for synchronous disease, another colonoscopy should be performed in 1 year to look for metachronous lesions. This recommendation is based on reports of a high incidence of apparently metachronous second cancers in the first 2 years after resection. If the examination at 1 year is normal, then the interval before the next subsequent examination should be 3 years. If that examination is normal, then the interval before the next subsequent examination should be 5 years. Shorter intervals may be indicated by associated adenoma findings (see "Guidelines for Colonoscopy Surveillance After Polypectomy: A Consensus Update by the US Multi-Society Task Force on Colorectal Cancer and the American Cancer Society"). Shorter intervals also are indicated if the patient's age, family history, or tumor testing indicate definite or probable hereditary nonpolyposis colorectal cancer. Patients undergoing low anterior resection of rectal cancer generally have higher rates of local cancer recurrence compared with those with colon cancer. Although effectiveness is not proven, performance of endoscopic ultrasound or flexible sigmoidoscopy at 3- to 6-month intervals for the first 2 years after resection can be considered for the purpose of detecting a surgically curable recurrence of the original rectal cancer.

High-definition chromocolonoscopy vs. high-definition white light colonoscopy for average-risk colorectal cancer screening

OBJECTIVES

Flat and depressed colon neoplasms are an increasingly recognized precursor for colorectal cancer (CRC) in Western populations. High-definition chromoscopy is used to increase the yield of colonoscopy for flat and depressed neoplasms; however, its role in average-risk patients undergoing routine screening remains uncertain.

METHODS

Average-risk patients referred for screening colonoscopy at four U.S. medical centers were randomized to high-definition chromocolonoscopy or high-definition white light colonoscopy. The primary outcomes, patients with at least one adenoma and the number of adenomas per patient, were compared between the two groups. The secondary outcome was patients with flat or depressed neoplasms, as defined by the Paris classification.

RESULTS

A total of 660 patients were randomized (chromocolonoscopy: 321, white light: 339). Overall, the mean number of adenomas per patient was 1.2+/-2.1, the mean number of flat polyps per patient was 1.4+/-1.9, and the mean number of flat adenomas per patient was 0.5+/-1.0. The number of patients with at least one adenoma (55.5% vs. 48.4%, absolute difference 7.1%, 95% confidence interval (-0.5% to 14.7%), P=0.07), and the number of adenomas per patient (1.3+/-2.4 vs. 1.1+/-1.8, P=0.07) were marginally higher in the chromocolonoscopy group. There were no significant differences in the number of advanced adenomas per patient (0.06+/-0.37 vs. 0.04+/-0.25, P=0.3) and the number of advanced adenomas<10 mm per patient (0.02+/-0.26 vs. 0.01+/-0.14, P=0.4). Two invasive cancers were found, one in each group; neither was a flat neoplasm. Chromocolonoscopy detected significantly more flat adenomas per patient (0.6+/-1.2 vs. 0.4+/-0.9, P=0.01), adenomas<5 mm in diameter per patient (0.8+/-1.3 vs. 0.7+/-1.1, P=0.03), and non-neoplastic lesions per patient (1.8+/-2.3 vs. 1.0+/-1.3, P<0.0001).

CONCLUSIONS

High-definition chromocolonoscopy marginally increased overall adenoma detection, and yielded a modest increase in flat adenoma and small adenoma detection, compared with high-definition white light colonoscopy. The yield for advanced neoplasms was similar for the two methods. Our findings do not support the routine use of high-definition chromocolonoscopy for CRC screening in average-risk patients. The high adenoma detection rates observed in this study may be due to the high-definition technology used in both groups.

Colonoscopy Surveillance After Colorectal Cancer Resection: Recommendations of the US Multi-Society Task Force on Colorectal Cancer

The US Multi-Society Task Force has developed updated recommendations to guide health care providers with the surveillance of patients after colorectal cancer (CRC) resection with curative intent. This document is based on a critical review of the literature regarding the role of colonoscopy, flexible sigmoidoscopy, endoscopic ultrasound, fecal testing and CT colonography in this setting. The document addresses the effect of surveillance, with focus on colonoscopy, on patient survival after CRC resection, the appropriate use and timing of colonoscopy for perioperative clearing and for postoperative prevention of metachronous CRC, specific considerations for the detection of local recurrence in the case of rectal cancer, as well as the place of CT colonography and fecal tests in post-CRC surveillance.

Sessile serrated polyp prevalence determined by a colonoscopist with a high lesion detection rate and an experienced pathologist

BACKGROUND

The prevalence of sessile serrated adenomas and/or polyps (SSA/Ps) is uncertain.

OBJECTIVE

To determine the prevalence of SSA/Ps and SSA/Ps with cytologic dysplasia (SSA/P-CD) by using a colonoscopist with a high lesion detection rate and an expert in serrated lesion pathology.

DESIGN

Retrospective screening colonoscopy study.

SETTING

Academic endoscopy unit.

PATIENTS

A total of 1910 average risk, asymptomatic patients aged ≥50 years underwent screening colonoscopy between August 2005 and April 2012 by a single colonoscopist with a high lesion detection rate.

INTERVENTIONS

Slides of all lesions in the serrated class proximal to the sigmoid colon and all rectal and sigmoid colon serrated lesions >5 mm in size were reviewed by an experienced GI pathologist.

MAIN OUTCOME MEASUREMENTS

Prevalence of SSA/Ps, defined as the proportion of patients with ≥1 SSA/P.

RESULTS

There were 1910 patients, of whom 389 had 656 lesions in the serrated class. Review by the experienced GI pathologist determined a prevalence of SSA/Ps without cytologic dysplasia of 7.4% and SSA/Ps-CD of 0.6% (total SSA/P prevalence 8.1%). SSA/Ps and SSA/Ps-CD comprised 5.6% and 0.3%, respectively, of all resected polyps. The mean size of SSA/Ps was 7.13 mm (standard deviation [SD] 4.66), and 51 of 77 (66.2%) polyps ≥10 mm in the serrated class were SSA/Ps.

LIMITATIONS

Retrospective design.

CONCLUSION

A colonoscopist with a high lesion detection rate and an experienced pathologist identified a high prevalence (8.1%) of SSA/Ps in a screening population. SSA/Ps are more common than previously believed.

High colonoscopic prevalence of proximal colon serrated polyps in average-risk men and women

BACKGROUND

Proximal colon serrated polyps likely contribute to the decreased protection of colonoscopy against right-sided colorectal cancer.

OBJECTIVE

To estimate the prevalence and extrapolated detection rate of proximal serrated polyps at screening colonoscopy.

DESIGN

Retrospective study.

PATIENTS

The study involved secondary analyses that used two databases. The first includes screening colonoscopies performed by 15 attending gastroenterologists at two academic endoscopy units between 2000 and 2009. The second includes average-risk patients who had previously participated in a randomized trial comparing high-definition chromocolonoscopy and white-light colonoscopy.

MAIN OUTCOME MEASUREMENTS

Prevalence of proximal serrated polyps found by the highest-level detectors and proximal serrated polyp detection rates corresponding to adenoma detection rates of 25% in men and 15% in women, respectively.

RESULTS

We analyzed 6681 procedures from the first database. Mean (± standard deviation) detection rates for adenomas and proximal serrated polyps were 38% ± 7.8% (range 17%-47%) and 13% ± 4.8% (1%-18%), respectively. There was a significant correlation between detection rates for adenomas and proximal serrated polyps for men (R = 0.71; P = .003) and women (R = 0.73; P = .002). Adenoma detection rates of 25% for men and 15% for women both corresponded to a detection rate of 4.5% for proximal serrated polyps. The prevalence of proximal serrated polyps found by the highest-level detector was 18%. The corresponding rate derived from the high-definition screening colonoscopy database was 20%.

LIMITATIONS

Retrospective study.

CONCLUSION

The prevalence of proximal colon serrated polyps in average-risk patients undergoing screening colonoscopy is higher than previously reported. An extrapolated proximal serrated polyp detection rate of 5% is suggested for average-risk men and women.

Impact of a quarterly report card on colonoscopy quality measures

BACKGROUND

Colonoscopy quality is operator-dependent. Studies assessing the effect of interventions to decrease variation in colonoscopy quality have shown inconsistent results. Since 2009, endoscopists at our university-affiliated, Veterans Affairs medical center have received a quarterly "report card" summarizing individual colonoscopy quality indicators as part of an ongoing quality assurance program.

OBJECTIVE

To determine the effect of the quality report card intervention on colonoscopy performance.

DESIGN

Retrospective study.

SETTING

Tertiary-care, academic, university-affiliated, Veterans Affairs medical center in Indianapolis, Indiana.

PATIENTS

Data from 6 endoscopists practicing at the Roudebush Veterans Affairs Medical Center were included. Patients were average-risk, aged 50 years or older, undergoing their first screening colonoscopy.

INTERVENTION

Quarterly report card. The study time frame was July 1, 2008 to December 31, 2008 (before-intervention) and April 1, 2009 to March 31, 2011 (intervention).

MAIN OUTCOME MEASUREMENTS

The primary outcomes were cecal intubation and adenoma detection rates (ADR), adjusted for physician, patient age, and sex. Multivariable logistic regression was performed to determine factors associated with adenoma detection.

RESULTS

A total of 928 patients (male 93%, white 78%) were included (before-intervention 336; intervention 592). There were no significant differences in patient age, sex, smoking status, body mass index, bowel preparation quality, colonoscope model, and proportion of colonoscopies performed with a trainee between the before-intervention and intervention phases. In the intervention phase, the adjusted adenoma detection and cecal intubation rates were significantly higher: 53.9% (95% confidence interval [CI], 49.7%-58.1%) vs 44.7% (95% CI, 39.1%-50.4%); P = .013 and 98.1% (95% CI, 96.7%-99.0%) vs 95.6% (95% CI, 92.5%-97.5%); P = .027, respectively. A higher ADR trend in the intervention phase was found for 5 of the 6 physicians. The increment in ADR was due mostly to increased detection of proximal adenomas. There were no significant changes in serrated polyp detection, advanced neoplasm detection, number of adenomas detected per colonoscopy, and mean size of adenomas after implementation of the intervention. The report card intervention remained significantly associated with higher ADRs after adjustment for patient age, sex, and physician (odds ratio 1.45; 95% CI, 1.08-1.94).

LIMITATIONS

Single center, small number of endoscopists.

CONCLUSION

A quarterly report card was associated with improved colonoscopy quality indicators. This intervention is practical to generate and implement and may serve as a model for quality improvement programs in different patient and physician groups.

Gastrointestinal histoplasmosis

Gastrointestinal histoplasmosis (GIH) is an uncommon disease with protean manifestations. It may occur as a result of mediastinal histoplasmosis or in the setting of progressive dissemination. GIH may be misdiagnosed as inflammatory bowel disease, malignancy, or other intestinal diseases leading to inappropriate therapies and unnecessary surgical interventions. Patients with bowel obstruction, perforation, or bleeding, and systemic findings suggestive of histoplasmosis should be evaluated for GIH. This is especially true for immunosuppressed patients, especially those with AIDS. Diagnosis first requires consideration of histoplasmosis in the differential in patients with the above types of gastrointestinal abnormalities, and second, familiarity with a battery of mycologic and serologic tests. Progressive disseminated histoplasmosis (PDH) is lethal if left untreated, and treatment is highly effective. This review will focus on the clinical and histopathologic features of GIH, the approach to diagnosis, and recommendations for treatment.

Guidelines for colonoscopy surveillance after cancer resection: a consensus update by the American Cancer Society and US Multi-Society Task Force on Colorectal Cancer

Patients with resected colorectal cancer are at risk for recurrent cancer and metachronous neoplasms in the colon. This joint update of guidelines by the American Cancer Society (ACS) and US Multi-Society Task Force on Colorectal Cancer addresses only the use of endoscopy in the surveillance of these patients. Patients with endoscopically resected Stage I colorectal cancer, surgically resected Stage II and III cancers, and Stage IV cancer resected for cure (isolated hepatic or pulmonary metastasis) are candidates for endoscopic surveillance. The colorectum should be carefully cleared of synchronous neoplasia in the perioperative period. In nonobstructed colons, colonoscopy should be performed preoperatively. In obstructed colons, double contrast barium enema or computed tomography colonography should be done preoperatively, and colonoscopy should be performed 3 to 6 months after surgery. These steps complete the process of clearing synchronous disease. After clearing for synchronous disease, another colonoscopy should be performed in 1 year to look for metachronous lesions. This recommendation is based on reports of a high incidence of apparently metachronous second cancers in the first 2 years after resection. If the examination at 1 year is normal, then the interval before the next subsequent examination should be 3 years. If that colonoscopy is normal, then the interval before the next subsequent examination should be 5 years. Shorter intervals may be indicated by associated adenoma findings (see Postpolypectomy Surveillance Guideline). Shorter intervals are also indicated if the patient's age, family history, or tumor testing indicate definite or probable hereditary nonpolyposis colorectal cancer. Patients undergoing low anterior resection of rectal cancer generally have higher rates of local cancer recurrence, compared with those with colon cancer. Although effectiveness is not proven, performance of endoscopic ultrasound or flexible sigmoidoscopy at 3- to 6-month intervals for the first 2 years after resection can be considered for the purpose of detecting a surgically curable recurrence of the original rectal cancer.

Endoscopic therapy versus medical therapy for bleeding peptic ulcer with adherent clot: a meta-analysis

BACKGROUND & AIMS

The optimal management of bleeding peptic ulcer with adherent clot is controversial and may include endoscopic therapy or medical therapy.

METHODS

We searched MEDLINE, BIOSIS, EMBASE, and the Cochrane Library to identify all randomized controlled trials comparing the 2 interventions. Outcomes evaluated in the meta-analysis were recurrent bleeding, need for surgical intervention, length of hospitalization, transfusion requirement, and mortality.

RESULTS

Six studies were identified that included 240 patients from the United States, Hong Kong, South Korea, and Spain. Patients in the endoscopic therapy group underwent endoscopic clot removal and treatment of the underlying lesion with thermal energy, electrocoagulation, and/or injection of sclerosants. Rebleeding occurred in 5 of 61 (8.2%) patients in the endoscopic therapy group, compared with 21 of 85 (24.7%) in the medical therapy group (P = .01), for a pooled relative risk of 0.35 (95% confidence interval, 0.14-0.83; number needed to treat, 6.3). There was no difference between endoscopic therapy and medical therapy in length of hospital stay (mean, 6.8 vs 5.6 days; P = .27), transfusion requirement (mean, 3.0 vs 2.8 units of packed red blood cells; P = .75), or mortality (9.8% vs 7%; P = .54). Patients in the endoscopic therapy group were less likely to undergo surgery (pooled relative risk, 0.43; 95% confidence interval, 0.19-0.98; number needed to treat, 13.3); however, this outcome became nonsignificant when only peer-reviewed studies were considered.

CONCLUSIONS

Endoscopic therapy is superior to medical therapy for preventing recurrent hemorrhage in patients with bleeding peptic ulcers and adherent clots. The interventions are comparable with respect to the need for surgical intervention, length of hospital stay, transfusion requirement, and mortality.

Improving measurement of the adenoma detection rate and adenoma per colonoscopy quality metric: the Indiana University experience

BACKGROUND

The adenoma detection rate (ADR) is a validated marker of colonoscopy quality. However, the optimal measurement method is unclear.

OBJECTIVE

The aims of our study were to (1) define benchmarks for the number of adenomas per screening colonoscopy (APC) quality metric; (2) study the association between ADRs for screening, surveillance, and diagnostic indications; and (3) explore the association of the screening ADR with an overall ADR inclusive of all colonoscopy indications.

DESIGN

Retrospective study.

SETTING

University hospital and associated ambulatory surgery center endoscopy units.

PATIENTS

Patients aged ≥50 years who underwent colonoscopy for screening, surveillance, or diagnostic indications by 20 endoscopists between January 1, 1999 and April 30, 2012.

INTERVENTION

Colonoscopy.

MAIN OUTCOME MEASUREMENTS

ADR, APC for screening, surveillance, and diagnostic indications.

RESULTS

A total of 21,766 colonoscopies were included. The indication was screening in 7434 (34.2%), surveillance in 8338 (38.3%), and diagnostic in 5994 (27.5%). The screening ADRs and APCs were significantly correlated (R = 0.91; P < .0001). For men, an ADR of 25% corresponded to an APC of 0.46 (95% confidence interval [CI], 0.35-0.57); for women, an ADR of 15% corresponded to an APC of 0.20 (95% CI, 0.13-0.27). Overall, the ADR stratified by colonoscopy indication was highest for surveillance, followed by screening, then diagnostic. For men, a screening ADR of 25% corresponded to a surveillance ADR of 31.9% (95% CI, 24.8%-38.9%); for women, an ADR of 15% corresponded to a surveillance ADR of 24.3% (95% CI, 18.3%-30.5%). The corresponding diagnostic ADRs were 17.0% (95% CI, 12.4%-21.6%) and 15.4% (95% CI, 11.5%-19.3%), respectively. There was significant correlation between screening ADR and an overall ADR inclusive of all colonoscopy indications.

LIMITATIONS

External generalizability, retrospective design.

CONCLUSION

We propose minimum screening APC detection benchmarks of 0.50 for men and 0.20 for women. ADRs for screening, surveillance, and diagnostic colonoscopy are correlated and can be used to derive a simplified overall ADR inclusive of all colonoscopy indications.

Narrow-band imaging versus white light for the detection of proximal colon serrated lesions: a randomized, controlled trial

BACKGROUND

The value of narrow-band imaging (NBI) for detecting serrated lesions is unknown.

OBJECTIVE

To assess NBI for the detection of proximal colon serrated lesions.

DESIGN

Randomized, controlled trial.

SETTING

Two academic hospital outpatient units.

PATIENTS

Eight hundred outpatients 50 years of age and older with intact colons undergoing routine screening, surveillance, or diagnostic examinations.

INTERVENTIONS

Randomization to colon inspection in NBI versus white-light colonoscopy.

MAIN OUTCOME MEASUREMENTS

The number of serrated lesions (sessile serrated polyps plus hyperplastic polyps) proximal to the sigmoid colon.

RESULTS

The mean inspection times for the whole colon and proximal colon were the same for the NBI and white-light groups. There were 204 proximal colon lesions in the NBI group and 158 in the white light group (P = .085). Detection of conventional adenomas was comparable in the 2 groups.

LIMITATIONS

Lack of blinding, endoscopic estimation of polyp location.

CONCLUSION

NBI may increase the detection of proximal colon serrated lesions, but the result in this trial did not reach significance. Additional study of this issue is warranted. (

CLINICAL TRIAL REGISTRATION NUMBER

NCT01572428.).

Bowel obstruction and pseudo-obstruction

The gastroenterologist is frequently involved in the care of patients with bowel obstruction and pseudo-obstruction. In the case of obstruction, the central problem is determining which patients should be managed surgically. In both SBO and LBO, evidence of vascular compromise to the gut mandates surgical intervention. Most patients with pseudo-obstruction respond to conservative therapy or neostigmine. Endoscopic decompression is indicated in recalcitrant cases, with surgery reserved as a last resort.

Colonoscopy Surveillance after Colorectal Cancer Resection: Recommendations of the US Multi-Society Task Force on Colorectal Cancer

The US Multi-Society Task Force has developed updated recommendations to guide health care providers with the surveillance of patients after colorectal cancer (CRC) resection with curative intent. This document is based on a critical review of the literature regarding the role of colonoscopy, flexible sigmoidoscopy, endoscopic ultrasound, fecal testing and CT colonography in this setting. The document addresses the effect of surveillance, with focus on colonoscopy, on patient survival after CRC resection, the appropriate use and timing of colonoscopy for perioperative clearing and for postoperative prevention of metachronous CRC, specific considerations for the detection of local recurrence in the case of rectal cancer, as well as the place of CT colonography and fecal tests in post-CRC surveillance.

Association between body mass index and quality of split bowel preparation

BACKGROUND & AIMS

Little is known about the association between obesity and bowel preparation. We investigated whether body mass index (BMI) is an independent risk factor for inadequate bowel preparation in patients who receive split preparation regimens.

METHODS

We performed a retrospective study of data from 2163 consecutive patients (mean age, 60.6 ± 10.5 y; 93.8% male) who received outpatient colonoscopies in 2009 at the Veterans Affairs Medical Center in Indianapolis, Indiana. All patients received a split preparation, categorized as adequate (excellent or good, based on the Aronchick scale) or inadequate. We performed a multivariable analysis to identify factors independently associated with inadequate preparation.

RESULTS

Bowel preparation quality was inadequate for 44.2% of patients; these patients had significantly higher mean BMIs than patients with adequate preparation (31.2 ± 6.5 vs 29.8 ± 5.9, respectively; P < .0001) and Charlson comorbidity scores (1.5 ± 1.6 vs 1.1 ± 1.4; P < .0001). Independent risk factors for inadequate preparation were a BMI of 30 kg/m(2) or greater (odds ratio [OR], 1.46; 95% confidence interval [CI], 1.21-1.75; P < .0001), use of tobacco (OR, 1.28; 95% CI, 1.07-1.54; P = .0084) or narcotics (OR, 1.28; 95% CI, 1.04-1.57; P = .0179), hypertension (OR, 1.30; 95% CI, 1.07-1.57; P = .0085), diabetes (OR, 1.38; 95% CI, 1.12-1.69; P = .0021), and dementia (OR, 3.02; 95% CI, 1.22-7.49; P = .0169).

CONCLUSIONS

BMI is an independent factor associated with inadequate split bowel preparation for colonoscopy. Additional factors associated with quality of bowel preparation include diabetes, hypertension, dementia, and use of tobacco and narcotics. Patients with BMIs of 30 kg/m(2) or greater should be considered for more intensive preparation regimens.

Colonoscopy and Colorectal Cancer Mortality in the Veterans Affairs Health Care System: A Case-Control Study

BACKGROUND

Colonoscopy is widely used in the Veterans Affairs (VA) health care system for colorectal cancer (CRC) prevention, but its effect on CRC mortality is unknown.

OBJECTIVE

To determine whether colonoscopy is associated with decreased CRC mortality in veterans and whether its effect differs by anatomical location of CRC.

DESIGN

Case-control study.

SETTING

VA-Medicare administrative data.

PARTICIPANTS

Case patients were veterans aged 52 years or older who were diagnosed with CRC between 2002 and 2008 and died of the disease by the end of 2010. Case patients were matched to 4 control patients without prior CRC on the basis of age, sex, and facility. Conditional logistic regression was performed to calculate odds ratios (ORs) for exposure to colonoscopy, with adjustment for race, Charlson Comorbidity Index score, selected chronic conditions, nonsteroidal anti-inflammatory drug use, and family history of CRC.

MEASUREMENTS

Exposure to colonoscopy was determined from 1997 to 6 months before CRC diagnosis in case patients and to a corresponding date in control patients. Subgroup analysis was performed for patients who had undergone screening colonoscopy.

RESULTS

A total of 4964 case patients and 19 856 control patients were identified. Case patients were significantly less likely to have undergone any colonoscopy (OR, 0.39 [95% CI, 0.35 to 0.43]). Colonoscopy was associated with reduced mortality for left-sided cancer (OR, 0.28 [CI, 0.24 to 0.32]) and right-sided cancer (OR, 0.54 [CI, 0.47 to 0.63]). The results were similar for patients who had undergone screening colonoscopy (overall OR, 0.30 [CI, 0.24 to 0.38]). Sensitivity analyses that varied the interval between CRC diagnosis and colonoscopy exposure did not affect the primary findings.

LIMITATION

Unmeasured confounding.

CONCLUSION

In this study using national VA-Medicare data, colonoscopy was associated with significant reductions in CRC mortality among veterans and was associated with greater benefit for left-sided cancer than right-sided cancer.

PRIMARY FUNDING SOURCE

U.S. Department of Veterans Affairs.

Survival of elderly persons undergoing colonoscopy: implications for colorectal cancer screening and surveillance

BACKGROUND

In the elderly, the increased prevalence of colorectal neoplasia and the protective effect of colonoscopy may be offset by advancing age and comorbidity.

OBJECTIVE

To describe and quantify the endoscopic findings, survival, and predictors of mortality of elderly persons after colonoscopy.

DESIGN, SETTING, AND PATIENTS

Retrospective cohort study of persons aged>or=75 years who underwent colonoscopy in 1999 and 2000 at a U.S. Veterans Affairs facility and urban county hospital.

MAIN OUTCOME MEASURES

Advanced neoplasms were defined as colorectal cancer (CRC), polyp with high-grade dysplasia, villous histologic features, or tubular adenoma>or=1 cm. Comorbidity was measured with the Charlson comorbidity index. Subjects were followed until death or study closure.

RESULTS

Of 469 eligible subjects, 65 were excluded and 404 were included in the study. Fifty-nine of 404 (15%) had an advanced neoplasm, including 8 (2%) with CRC. There were 167 deaths (41%); the mean overall survival was 4.1+/-0.1 years (median 5.95 years). A symptomatic indication for colonoscopy was not predictive of death. Mortality was predicted by age (hazard ratio 1.16 for each year increase beyond age 75 years, 95% CI 1.07-1.3, P=.0003) and Charlson score (hazard ratio 8.3 for each point increase, 95% CI 1.4-48.5, P=.02). The median survival of patients aged 75 to 79 years was >5 years if the Charlson score was <or=4. Among patients aged>or=80 years, the median survival was <5 years regardless of Charlson score.

LIMITATIONS

Retrospective design.

CONCLUSIONS

In this cohort of elders, age and comorbidity were predictors of death. The protective effect of younger age lessens as comorbidity increases. These findings may have important implications for CRC screening and surveillance in elders.

Efficacy and effectiveness of colonoscopy: how do we bridge the gap?

Colonoscopy is sometimes considered the preferred colorectal cancer screening modality, yet this modality may be subject to variation in operator performance more than any other screening test. Failures of colonoscopy to consistently detect precancerous lesions threaten the effectiveness of this technique for the prevention of colorectal cancer. Studies on high-level adenoma detectors under optimal conditions have begun to establish the true efficacy of colonoscopy and further widen the gap between efficacy and effectiveness. Research is required to establish the component skills, attitudes, and behaviors for high-level mucosal inspection competence necessary for training and assessment. Interventions to bridge the gap between efficacy and effectiveness are lacking, yet they should emphasize quality measurement and operate at various levels within the health system to motivate change in endoscopist behavior.

Lower endoscopy reduces colorectal cancer incidence in older individuals

BACKGROUND & AIMS

In older individuals, there are unclear effects of lower endoscopy on incidence of colorectal cancer (CRC) and of colonoscopy on site of CRC. We investigated whether sigmoidoscopy or colonoscopy is associated with a decreased incidence of CRC in older individuals, and whether the effect of colonoscopy differs by anatomic location.

METHODS

We performed a case-control study using linked US Veterans Affairs and Medicare data. Cases were veterans aged 75 years or older diagnosed with CRC in fiscal year 2007. Cases were matched for age and sex to 3 individuals without a CRC diagnosis (controls). We determined the number of cases and controls who received colonoscopies or sigmoidoscopies from fiscal year 1997 to a date 6 months before the diagnosis of CRC (for cases) or to a corresponding index date (for controls). The probability of exposure was modeled using generalized linear mixed equations, adjusted for potential confounders. For the analysis of CRC risk in different anatomic locations, the proximal colon was defined as proximal to the splenic flexure.

RESULTS

We identified 623 cases and 1869 controls (mean age, 81 y; 98.7% male, 86.2% Caucasian). Among cases, 243 (39.0%) underwent any lower endoscopy (177 colonoscopies). Among controls, 978 (52.3%) underwent any lower endoscopy (758 colonoscopies). Cases were significantly less likely than controls to have undergone lower endoscopy within the preceding 10 years (adjusted odds ratio [aOR], 0.58; 95% confidence interval [CI], 0.48-0.69). This effect was significant for colonoscopy (aOR, 0.57; 95% CI, 0.47-0.70), but not sigmoidoscopy. Similar results were observed when a 5-year exposure window was applied. Colonoscopy was associated with a reduced risk of distal CRC (aOR, 0.45; 95% CI, 0.32-0.62) and proximal CRC (aOR, 0.65; 95% CI, 0.46-0.92).

CONCLUSIONS

In a study of the US Veterans Affairs and Medicare databases, lower endoscopy in the preceding 10 years was associated with a significant reduction in CRC incidence among older veterans. Colonoscopy was associated with significant reductions in distal and proximal CRC.