Fecal occult blood test in patients on low-dose aspirin, warfarin, clopidogrel, or non-steroidal anti-inflammatory drugs.

AIM: To determine the effect of anticoagulants and antiplatelet medications on the positive-predictive-value of fecal occult blood test (FOBT). METHODS: All patients who underwent a colonoscopy at our institution from 1995 to 2006 for a positive FOBT were identified. Medical records were searched, and patients were stratified into five groups selected a priori: low-dose aspirin, NSAIDs, warfarin, clopidogrel, or controls. The positive-predictive-value of FOBT for advanced colonic neoplasia was computed for each group. RESULTS: During the study period, 1,126 patients underwent colonoscopy for a positive FOBT and met entry criteria. The average age of study participants was 69 years and most were men. The positive-predictive-value of FOBT for advanced colon neoplasia was significantly higher in the control group (30.5%) when compared to those on low-dose aspirin (20.5%; p = 0.003), NSAIDs (19.7%; p = 0.003), clopidogrel (7.3%; p = 0.002), or warfarin (20%; p = 0.05). The positive-predictive-value of FOBT was significantly lower for those on clopidogrel than those on low-dose aspirin (p = 0.04) and NSAIDs (p = 0.05), but not warfarin (p = 0.08). The positive-predictive-value for FOBT was similar for those on aspirin, NSAIDs, and warfarin. There was a linear trend between the number of number of positive FOBT cards and prevalence of advanced colon neoplasia (p = 0.01). CONCLUSION: Anticoagulants and antiplatelet medications lower the positive-predictive-value of FOBT for advance colonic neoplasia and should be stopped if clinically feasible prior to stool collection.

Plastic versus self-expanding metallic stents for malignant hilar biliary obstruction: a prospective multicenter observational cohort study.

BACKGROUND: There are few comparative data as to whether plastic or self-expanding metallic stents are preferable for palliating malignant hilar biliary obstruction. METHODS: Thirty-day outcomes of consecutive endoscopic retrograde cholangiopancreatographies performed for malignant hilar obstruction at 6 private and 5 university centers were assessed prospectively. RESULTS: Patients receiving plastic (N=28) and metallic stents (N=34) were similar except that metallic stent recipients more often had: Bismuth III or IV tumors (16/34 vs. 5/28 P=0.043), higher Charlson comorbidity scores (P=0.003), metastatic disease (P=0.006), and management at academic centers (P=0.018). The groups had similar rates of bilateral stent placement (4/28 vs. 5/34), and similar frequency of opacified but undrained segmental ducts (7/28 vs. 5/34). Adverse outcomes including cholangitis, stent occlusion, migration, perforation, and/or the need for unplanned endoscopic retrograde cholangiopancreatography or percutaneous transhepatic cholangiography occurred in 11/28 (39.3%) patients with plastic versus 4/34 (11.8%) with metal stents (P=0.017). By logistic regression, factors associated with adverse outcomes included plastic stent placement (odds ratio 6.32; 95% confidence interval 1.23, 32.56) and serum bilirubin (1.11/mg/dL above normal: 1.01, 1.22) but not center type or Bismuth class. CONCLUSIONS: Metallic stent performance was superior to plastic for hilar tumor palliation with respect to short-term outcomes, independent of disease severity, Bismuth class, or drainage quality.

Five-year colon surveillance after screening colonoscopy.

BACKGROUND & AIMS: Outcomes of colon surveillance after colorectal cancer screening with colonoscopy are uncertain. We conducted a prospective study to measure incidence of advanced neoplasia in patients within 5.5 years of screening colonoscopy. METHODS: Three thousand one hundred twenty-one asymptomatic subjects, age 50 to 75 years, had screening colonoscopy between 1994 and 1997 in the Department of Veterans Affairs. One thousand one hundred seventy-one subjects with neoplasia and 501 neoplasia-free controls were assigned to colonoscopic surveillance over 5 years. Cohorts were defined by baseline findings. Relative risks for advanced neoplasia within 5.5 years were calculated. Advanced neoplasia was defined as tubular adenoma greater than > or =10 mm, adenoma with villous histology, adenoma with high-grade dysplasia, or invasive cancer. RESULTS: Eight hundred ninety-five (76.4%) patients with neoplasia and 298 subjects (59.5%) without neoplasia at baseline had colonoscopy within 5.5 years; 2.4% of patients with no neoplasia had interval advanced neoplasia. The relative risk in patients with baseline neoplasia was 1.92 (95% CI: 0.83-4.42) with 1 or 2 tubular adenomas <10 mm, 5.01 (95% CI: 2.10-11.96) with 3 or more tubular adenomas <10 mm, 6.40 (95% CI: 2.74-14.94) with tubular adenoma > or =10 mm, 6.05 (95% CI: 2.48-14.71) for villous adenoma, and 6.87 (95% CI: 2.61-18.07) for adenoma with high-grade dysplasia. CONCLUSIONS: There is a strong association between results of baseline screening colonoscopy and rate of serious incident lesions during 5.5 years of surveillance. Patients with 1 or 2 tubular adenomas less than 10 mm represent a low-risk group compared with other patients with colon neoplasia.

Impact of preoperative endoscopic ultrasound on non-small cell lung cancer staging.

AIM: To determine if the addition of preoperative endoscopic ultrasound (EUS) to non-small cell lung cancer staging can reduce the proportion of patients in whom malignant mediastinal lymph nodes (inoperable disease) are discovered at surgery. METHODS: All patients with lung cancer who underwent mediastinoscopy or thoracotomy for cancer diagnosis, staging, or treatment from 1999 to 2005 were identified. Patients who had undergone preoperative EUS were designated as the EUS group. The control group was composed of similar patients who had not undergone preoperative EUS, and were frequency matched to those in the EUS group in a 3:1 ratio by preoperative cancer stage. The proportion of patients in whom malignant mediastinal lymph nodes were diagnosed at surgery was the primary outcome. RESULTS: Forty-four patients (average age, 67.8 years) met criteria for the EUS group, and 132 patients (average age, 67.4 years) were selected as control subjects. Overall, in the EUS group, 3 of 44 patients (6.8%) were found to have malignant mediastinal lymph nodes at surgery, compared with 41 of 132 patients (31.1%) in the control group (p = 0.003). In patients undergoing thoracotomy for cancer resection, 3% in the EUS group, compared with 20% in the control group, were found to have malignant mediastinal lymph nodes at surgery (p = 0.01). There was also a trend toward lower yield of mediastinoscopy done for cancer diagnosis or staging in the EUS group (p = 0.08). CONCLUSIONS: Preoperative EUS in lung cancer patients may reduce unnecessary surgery at which advanced inoperable disease is discovered.

Central intranodal blood vessel: a new EUS sign described in mediastinal lymph nodes.

BACKGROUND: The vascular architecture of normal lymph nodes is composed of prominent centrally located blood vessels. In malignant nodes, this pattern is distorted because of tumor infiltration and neovascularization. OBJECTIVE: To determine whether EUS imaging of central intranodal blood vessels (CIV) can be used to differentiate benign from malignant subcarinal lymph nodes in lung cancer. DESIGN: CIV was defined as a > or =1-mm-diameter tubular structure, with well-defined walls and blood flow. The diagnostic accuracy of CIV was compared with other lymph-node features in a retrospective cohort of patients who underwent EUS for lung cancer evaluation. Findings were then prospectively validated in a similar cohort. SETTING: Minneapolis Veterans Affairs Medical Center. PATIENTS: Patients who underwent EUS for lung cancer diagnosis or staging at the VA Medical Center from March 2003 to March 2005. RESULTS: Of 67 patients included in the retrospective analysis, CIV was noted in 17 of 35 patients with benign nodes (49%), compared with 5 of 32 patients with malignant nodes (16%) (P = .002). In lymph nodes > or =1 cm, CIV was noted in 14 of 16 patients with benign nodes (88%), compared with 2 of 27 with malignant nodes (7%) (P < .001). Forty-five patients were included in the prospective validation cohort, and 16 had malignant lymph nodes. For malignant lymph-node metastasis, the absence of CIV had a sensitivity of 75%, a specificity of 97%, and an accuracy of 89%. The accuracy of CIV was superior to that of lymph-node shape; margin; and internal echo pattern, singly or in combination. CONCLUSIONS: The absence of a central intranodal blood vessel was a strong and independent predictor of malignancy in lymph nodes of patients with lung cancer and can be used to select lymph nodes for FNA.

Should patients with anemia and low normal or normal serum ferritin undergo colonoscopy?

BACKGROUND: Patients with unexplained iron deficiency anemia have a greater prevalence of colonic neoplasia, and should be evaluated for a colonoscopy. The approach to patients with anemia without iron deficiency remains unclear. OBJECTIVE: To compare the prevalence of colonic neoplasia in anemic patients with normal ferritin (>50 ng/mL), to those with ferritin < or =50 ng/mL, and nonanemic individuals. METHODS: Patients referred for colonoscopy for anemia evaluation were stratified into 3 groups: ferritin < or =50 ng/mL, 51-100 ng/mL, and >100 ng/mL. We compared these groups to each other, and to asymptomatic nonanemic individuals undergoing screening colonoscopy. The prevalence of advanced colonic neoplasia was determined for each group using existing records. RESULTS: During the study period, 414 patients who underwent colonoscopy for anemia evaluation and 323 nonanemic individuals who underwent colonoscopy for cancer screening met inclusion criteria. Study subjects were mostly men. The prevalence of advanced colonic neoplasia in subjects with ferritin 51-100 ng/mL was 7.2% (95% CI 2.4-17.9%), similar to 7.9% (95% CI 5.1-11.9%) in those with ferritin < or =50 ng/mL. The incidence of advanced colonic neoplasia in subjects with ferritin >100 ng/mL was 1.7% (95% CI 0.1-6.6%), similar to 1.2% (95% CI 0.4-3.3%) in the asymptomatic nonanemic group. After adjusting for age, patients with ferritin < or =50 ng/mL and 51-100 ng/mL were almost 5 times more likely to harbor advanced colonic neoplasia than the other groups. The addition of other laboratory parameters did not improve the predictive value of ferritin. CONCLUSION: A ferritin cutoff of 100 ng/mL can be used to determine the need for colonoscopy in men with anemia.

Microsatellite instability in interval colon cancers.

BACKGROUND & AIMS: Colon cancers that develop after a complete colonoscopy may be the result of "failure of colonoscopy" or rapid tumor growth. Tumors that develop via the mismatch repair gene pathway demonstrate rapid tumor growth. The aim of this study was to determine if interval colon cancers were more likely than noninterval cancers to result from the loss of function of mismatch repair genes and hence demonstrate microsatellite instability (MSI). METHODS: We searched our institution's cancer registry for interval cancers, defined as colon cancers that developed within 5 years of a complete colonoscopy. These were frequency matched in a 1:2 ratio by age and sex to patients with noninterval cancers (defined as colon cancers diagnosed on a patient's first recorded colonoscopy). Archived cancer specimens for all subjects were retrieved and tested for MSI. RESULTS: Of the 993 colon cancers diagnosed during the study period, 51 (5.1%) were identified as an interval cancer, and 112 subjects with noninterval cancer served as a comparison group. Study subjects were almost all men. MSI was found in 30.4% of interval cancers compared with 10.3% of noninterval cancers (P = .003). After adjusting for age, interval cancers were 3.7 times more likely to show MSI than noninterval cancers (95% confidence interval, 1.5-9.1). This association was strongest for tumors located in the distal colon (odds ratio, 17.5; P = .008). No difference in TNM stage at diagnosis, histologic type or grade, or 5-year survival was found between groups. CONCLUSIONS: Interval colon cancers were almost 4 times as likely as noninterval colon cancers to be associated with mismatch repair gene dysfunction.

Colorectal cancers found after a complete colonoscopy.

BACKGROUND & AIMS: The incidence of colorectal cancer in patients undergoing colonoscopic surveillance is higher than previously thought. A better understanding of interval cancers is needed to improve surveillance strategies. The objectives of this study were to determine whether interval colorectal cancers were associated with an inadequate earlier colonoscopy, incomplete polypectomy, or aggressive biologic behavior. METHODS: We searched our institution's cancer registry. Interval cancers were defined as colorectal cancers that developed within 5 years of a complete colonoscopy. These were frequency matched in a 1:2 ratio to patients with sporadic cancers, which were defined as colorectal cancers diagnosed on a patient's first recorded colonoscopy. Patient, colonoscopy, and tumor characteristics of interval and sporadic cancers were compared. RESULTS: Of the 830 colorectal cancers diagnosed during the study period, 45 patients developed an interval cancer (5.4%; 95% confidence interval, 4.1%-7.2%). Twenty-seven percent of interval cancers developed at previous polypectomy segments, and location of polypectomy segments was predictive of the location of subsequent interval cancers. Interval cancers were 3 times more likely to occur in the right colon and were smaller in size than sporadic cancers. Quality of bowel preparation, individual endoscopist, endoscopist experience, and trainee involvement were not associated with interval cancers. No difference in TNM stage at diagnosis, histologic type or grade, carcinoembryonic antigen level, or 5-year survival was found between interval and sporadic cancers. CONCLUSIONS: Incomplete polypectomy might play an important role in the development of interval colorectal cancer. No association between other colonoscopy-related factors or tumor characteristics and interval cancers was found.

Current issues in endoscope reprocessing and infection control during gastrointestinal endoscopy.

The purpose of this article is to review the evidence regarding transmission of infection during gastrointestinal endoscopy, factors important in endoscope reprocessing and infection control, areas to focus on to improve compliance, and recent developments and advances in the field.

Endoscopic ultrasound and positron emission tomography for lung cancer staging.

BACKGROUND AND AIMS: Accurate assessment of mediastinal lymph nodes is vital for optimum treatment allocation in lung cancer patients. Currently available strategies fail to identify many patients with advanced mediastinal disease, resulting in unnecessary surgery. We prospectively compared 2 promising new modalities, positron emission tomography (PET) and endoscopic ultrasound (EUS), for staging mediastinal lymph nodes. METHODS: Consenting patients with lung cancer who also were suitable candidates for surgery were enrolled in the study. Patients underwent both PET and EUS. Outcomes were analyzed by surgery results or follow-up with serial imaging. RESULTS: Seventy-two eligible patients were enrolled, and adequate data were available for 65 patients. The final diagnosis was based on tissue analysis in 59 patients and 1-year radiologic follow-up evaluation in 6 patients. PET correctly diagnosed mediastinal lymph node status in 77% of patients, and EUS fine-needle aspiration was correct in 94% of patients (P = .012). The overall sensitivity, specificity, and accuracy of PET were 61%, 91%, and 77% compared with 87%, 100%, and 94% for EUS. We estimated that EUS obviated a surgical procedure in 55% (95% confidence interval, 40%-69%) of patients with radiologic evidence of mediastinal metastasis, and in 22% (95% confidence interval, 10%-41%) of patients without radiologic evidence of mediastinal metastasis. CONCLUSIONS: EUS fine-needle aspiration was more accurate than PET in staging mediastinal lymph nodes in lung cancer patients, and resulted in a substantial reduction in mediastinoscopy and thoracotomy.

EUS-guided FNA for the diagnosis of advanced lung cancer.

BACKGROUND: A majority of patients with lung cancer are incurable but are symptomatic and may benefit from palliative therapy. Currently available diagnostic methods are either too risky or unsuccessful in obtaining a tissue diagnosis in up to 30% of patients. OBJECTIVE: To evaluate the role of EUS-guided FNA in obtaining a tissue diagnosis in patients with advanced lung cancer. DESIGN: Prospective, uncontrolled. SETTING: Veterans Administration Medical Center. SUBJECTS AND METHODS: Patients with suspected lung cancer who were not candidates for curative therapy were prospectively identified. CT scans were reviewed, and patients with lesions considered suitable for sampling by EUS were enrolled. Outcomes were analyzed by a final tissue diagnosis or by serial imaging. RESULTS: Sixty-nine patients met inclusion criteria, of which 3 refused participation. The remaining 66 patients constituted the study population. EUS was technically successful in 95% of patients. A final diagnosis was based on tissue in 63 of 66 patients, serial imaging in 1 of 66 patients, and was unavailable in 2 of 66 patients. A lung mass was sampled in 21 patients, and a metastatic lesion was sampled in 45 patients. EUS made a correct diagnosis in 55 of 64 patients (86%, 95% confidence interval [CI] 77%-93%), including 24% that had undergone a failed prior attempt at diagnosis. The sensitivity of EUS was 86%, and the specificity was 100%. Sampling a metastasis was more likely to yield a correct diagnosis than sampling a lung mass (P = .02). Two self-limited complications were noted during the study. CONCLUSIONS: EUS was an accurate and a safe method for obtaining a tissue diagnosis in patients with advanced incurable lung cancer.