Perspectives of chromo and magnifying endoscopy: how, how much, when, and whom should we stain?

The goal of every routine endoscopy in the gut is the early diagnosis of malignant and premalignant changes of the mucosa. Chromo- and magnifying endoscopes are exciting new tools and offer detailed analysis of the colonic mucosal surface and pit pattern architecture. This review summarizes recent advances in endoscopic characterization of colorectal lesions using magnification endoscopy and chromoendoscopy. Surface analysis of the colon using chromoendoscopy allows a prediction between non-neoplastic and neoplastic lesions with high specificity. The precise delineation of the borders and a more detailed macroscopic analysis of the lesions are further advantages. In particular, flat adenomas and early depressed cancers are now more frequently recognized in western countries suggesting that significant lesions were overlooked by conventional endoscopy in the past. Furthermore, chromoendoscopy can be used in a targeted fashion to screen for sporadic adenomas. Finally, in surveillance colonoscopy, patients with long-standing ulcerative colitis have a valuable benefit if targeted biopsies are performed to detect intraepithelial neoplasias after pan-chromoendoscopy with methylene blue. Although there is a long learning curve, chromoendoscopy should thus belong to every endoscopists armamentarium. However, detailed knowledge about the technique, dyes, and specific staining patterns are mandatory before the yield of screening or surveillance colonoscopy can be increased. The new detailed images seen with magnifying chromoendoscopy are unequivocally the beginning of a new era where new optical developments will allow a unique look on cellular structures.

Risk factors for post-ERCP pancreatitis: a prospective, multicenter study.

BACKGROUND: Post-ERCP pancreatitis is poorly understood. The goal of this study was to comprehensively evaluate potential procedure- and patient-related risk factors for post-ERCP pancreatitis over a wide spectrum of centers. METHODS: Consecutive ERCP procedures were prospectively studied at 11 centers (6 private, 5 university). Complications were assessed at 30 days by using established consensus criteria. RESULTS: Pancreatitis occurred after 131 (6.7%) of 1963 consecutive ERCP procedures (mild 70, moderate 55, severe 6). By univariate analysis, 23 of 32 investigated variables were significant. Multivariate risk factors with adjusted odds ratios (OR) were prior ERCP-induced pancreatitis (OR 5.4), suspected sphincter of Oddi dysfunction (OR 2.6), female gender (OR 2.5), normal serum bilirubin (OR 1.9), absence of chronic pancreatitis (OR 1.9), biliary sphincter balloon dilation (OR 4.5), difficult cannulation (OR 3.4), pancreatic sphincterotomy (OR 3.1), and 1 or more injections of contrast into the pancreatic duct (OR 2.7). Small bile duct diameter, sphincter of Oddi manometry, biliary sphincterotomy, and lower ERCP case volume were not multivariate risk factors for pancreatitis, although endoscopists performing on average more than 2 ERCPs per week had significantly greater success at bile duct cannulation (96.5% versus 91.5%, p = 0.0001). Combinations of patient characteristics including female gender, normal serum bilirubin, recurrent abdominal pain, and previous post-ERCP pancreatitis placed patients at increasingly higher risk of pancreatitis, regardless of whether ERCP was diagnostic, manometric, or therapeutic. CONCLUSIONS: Patient-related factors are as important as procedure-related factors in determining risk for post-ERCP pancreatitis. These data emphasize the importance of careful patient selection as well as choice of technique in the avoidance of post-ERCP pancreatitis.

Endoscopic therapy for stenosis of the biliary and pancreatic duct orifices.

BACKGROUND: Manipulation of the duodenal papilla may lead to symptomatic stenosis of the orifices of bile duct, main pancreatic duct or accessory pancreatic duct. METHODS: Seventeen patients with stenosis of the orifice (bile duct 7, bile duct/main pancreatic duct 7, accessory pancreatic duct 3) underwent sphincterotomy and/or dilation and stent placement for a median of 140 days (range 30 to 1080 days). Patients were interviewed at a median of 720 days (range 120 to 990 days) after removal of the final stent. RESULTS: Median age was 50 years (range 17 to 68 years); 78% were women. The etiology of stenosis of the orifice was sphincterotomy in 8, sphincteroplasty in 7 and papillectomy in 2 patients. Indications for treatment were abdominal pain (100%), dilated bile duct and/or main pancreatic duct (14 patients) and pancreas divisum (3 patients). Sixty procedures (median 4 per patient) were performed with mild morbidity (hospital stay less than 3 days) in 17% of procedures and 35% of patients. Symptoms improved in 100%, 57% and 33% of patients with bile duct, bile duct/main pancreatic duct and accessory pancreatic duct, respectively. Surgery was ultimately needed in 3 (43%) patients with bile duct/main pancreatic duct and 2 (67%) with accessory pancreatic duct stenosis. CONCLUSIONS: Endoscopic therapy successfully relieves pain due to biliary stenosis of the orifice but less frequently relieves pain due to pancreatic stenosis of the orifice.

KTP laser therapy for bleeding from chronic radiation proctopathy.

BACKGROUND: Endoscopic laser photocoagulation is commonly used to treat bleeding from the neovascular lesions of chronic radiation proctopathy. The KTP laser is an Nd/YAG-driven unit that emits light with a wavelength of 532 nm. This wavelength of energy is absorbed by hemoglobin and penetrates tissue to a depth of only 1 to 2 mm. METHODS: Twenty-three patients were treated with KTP laser and followed for a median of 29 months (range 5 to 51 months); 21 had received radiation for prostate cancer and 2 for uterine cancer. The median age was 77 years (range 68 to 87 years). A median of 2 sessions (range 1 to 5 sessions) was performed using 4 to 10 Watts of power and a median energy of 816 Joules per session (range 204 to 2430 Joules). RESULTS: After treatment there was a significant reduction in the frequency (p = 0.0005) of bleeding, increase in hematocrit level (p < 0.0001), improvement in activities of daily life (p = 0.01), and a reduction in use of health care resources (p < 0.0001). There was a trend toward decreased use of iron supplements (11 to 4 patients) and transfusions (4 to 0 patients). Two patients (9%) developed rectal ulcers after treatment. CONCLUSIONS: KTP laser photocoagulation is a safe and effective therapy for bleeding from chronic radiation proctopathy that improves activities of daily living and reduces use of health care resources.

Same-day discharge after endoscopic biliary sphincterotomy: observations from a prospective multicenter complication study. The Multicenter Endoscopic Sphincterotomy (MESH) Study Group.

BACKGROUND: Same-day discharge after endoscopic biliary sphincterotomy (ES) is a common clinical practice, but there have been few data to guide appropriate selection of patients. Using a prospective, multicenter database of complications, we examined outcomes after same-day discharge as it was practiced by a variety of endoscopists and evaluated the ability of a multivariate risk factor analysis to predict which patients would require readmission for complications. METHODS: A 150-variable database was prospectively collected at time of ES, before discharge and again at 30 days in consecutive patients undergoing ES at 17 centers. Complications were defined by consensus criteria and included all specific adverse events directly or indirectly related to ES requiring more than 1 night of hospitalization. RESULTS: Six hundred fourteen (26%) of 2347 patients undergoing ES were discharged on the same day as the procedure, ranging from none at 6 centers to about 50% at 2 centers. After initial observation and release, readmission to the hospital for complications occurred in 35 (5.7%) of 614 same-day discharge patients (20 pancreatitis and 15 other complications, 3 severe). Of the same-day discharge patients, readmission was required for 14 (12.2%) of 115 who had at least one independently significant multivariate risk factor for overall complications (suspected sphincter of Oddi dysfunction, cirrhosis, difficult bile duct cannulation, precut sphincterotomy, or combined percutaneous-endoscopic procedure) versus 21 (4.2%) of 499 without a risk factor (odds ratio 3.1: 95% confidence interval [1.6, 6.3], p < 0.001). Of complications presenting within 24 hours after ES, only 44% presented within the first 2 hours, but 79% presented within 6 hours. CONCLUSIONS: Same-day discharge is widely utilized and relatively safe but results in a significant number of readmissions for complications. For patients at higher risk of complications, as indicated by the presence of at least one of five independent predictors, observation for 6 hours or overnight may reduce the need for readmission.

Dilation of refractory pancreatic duct strictures: the turn of the screw.

BACKGROUND: Endoscopic pancreatic ductal drainage may improve pain from chronic pancreatitis but stricture dilation may be technically difficult. METHODS: Eight patients with refractory pancreatic strictures had dilation with a Soehendra stent retriever. Each had sphincterotomy, guidewire placement, stent retriever dilation to 7F to 10F, and stenting for 6 to 12 months. RESULTS: All procedures were successful and 1 (13%) was complicated by mild pancreatitis. The mean follow-up was 21 months. Each patient had substantial pain relief with patent stents in place, but 7 (88%) relapsed with stent occlusion or removal. Four (50%) patients underwent surgery with excellent results. However, endoscopic therapy alone resulted in just modest benefits or pain recurrence in 3 (38%) and persistent relief in only 1 (13%). CONCLUSIONS: The Soehendra stent retriever is effective as a dilating device for pancreatic strictures resistant to conventional dilation. However, substantial symptom relief may persist only while patent stents are in place.

Colon cancer screening. Sigmoidoscopy or colonoscopy.

Colorectal cancer is a common neoplasia with high morbidity and mortality. With endoscopy it is possible to identify its precursor lesion, the adenoma, and early localized cancer. Early detection and removal of adenomas can reduce the incidence and mortality of this disease. Studies using fecal occult blood testing (FOBT) and sigmoidoscopy for screening asymptomatic patients demonstrate a reduction in mortality from colorectal cancer. Colonoscopy, however, has the highest yield for detecting polyps. Most authorities and organizations now recommend screening the asymptomatic population over age 50 for colorectal neoplasia. The estimated cost of colon cancer screening is well within the benchmark figure of $40,000 per year of life saved, which is considered by the government to be cost effective. Controversies still exist regarding which colon cancer screening strategy is the most sensitive, specific, acceptable to the population, and cost effective. The American Cancer Society recommends a combination of FOBT and flexible sigmoidoscopy, but some experts believe that a one-time colonoscopy at age 60 may be a more cost-effective method. If the costs of colonoscopy are reduced, it is more cost effective than other techniques. Colonoscopy also may help to stratify at-risk patients, and those with negative initial colonoscopy may not need further screening. Advances in molecular biology may provide markers for screening or identifying people who are at high risk for colorectal neoplasia. This development may allow screening to be directed at high-risk groups.

Gastric outlet obstruction.

Acquired gastric outlet obstruction is more commonly owing to malignancy than ulcer disease. Endoscopy is the preferred method for diagnosis. Surgical palliation for malignant disease has poor results and high rates of morbidity and mortality. Initial experiences with endoscopic palliation with expandable metallic endoprostheses appear promising. Peptic ulcer-induced gastric outlet obstruction can be treated safely with endoscopic balloon dilation. About 65% of patients have sustained symptom relief, but many require more than one dilation session. Outcomes may be improved with effective ulcer therapy with acid reduction and eradication of H. pylori. Surgery is associated with significant morbidity and mortality and should be reserved for endoscopic treatment failures.

Needle-knife sphincterotomy as a precut procedure: a retrospective evaluation of efficacy and complications.

BACKGROUND AND STUDY AIMS: Precut sphincterotomy remains a controversial means of gaining biliary access during endoscopic retrograde cholangiopancreatography (ERCP). This report is a retrospective evaluation of the use of needle-knife sphincterotomy as a precut procedure to achieve biliary access during ERCP. PATIENTS AND METHODS: From November 1992 to August 1993, a total of 1071 ERCPs were performed at our institution. During this time, precut sphincterotomy was carried out in 180 patients, with complete follow-up obtained in 178 patients. The follow-up concentrated on the efficacy of the procedure and short-term complications. RESULTS: Cannulation of the common bile duct was achieved immediately after precut sphincterotomy in 88% of the patients, and during a second ERCP in an additional 11% of patients (total success rate 99%). There were no precut-related deaths. The complication rate of precut sphincterotomy was 21 in 178 (12%). Complications included bleeding in ten patients (5.5%), perforation in four patients (3%), pancreatitis in one patient (0.5%), and fever of unknown origin in six (3%) patients. All complications were managed conservatively. CONCLUSIONS: Precut sphincterotomy is a safe and highly effective method of gaining biliary access in patients in whom deep cannulation proves difficult or impossible and biliary access is considered essential.

Transjugular intrahepatic portosystemic shunt: midterm clinical and angiographic follow-up.

PURPOSE: To determine the impact of Child class and indication for transjugular intrahepatic portosystemic shunt (TIPS) placement on patient survival and reintervention rate. MATERIALS AND METHODS: Metal stents were used to successfully create single shunts in 63 patients during a 3-year period. Angioplasty and repeated stent placement were used to maintain shunt patency, and patients were followed up clinically and angiographically. Statistical analysis of survival and patency was performed with Kaplan-Meier product-limit survival functions. A Karnofsky performance status score was derived for each follow-up encounter. RESULTS: Early and late mortalities varied with Child class and procedure indications. Thirty-day mortality was 19% overall (12 of 63 patients) and was 33% for Child class C patients (10 of 30 patients). Thirty-day mortality was 31% (four of 13 patients) for patients with ascites and 16% (eight of 50 patients) for those with bleeding. Reintervention was required in 20 of 33 patients and was not predictable on the basis of Child class. CONCLUSION: Child class and indication for procedures are significant predictors of survival but not of the need for reintervention. Ninety-day survivors had uniformly good performance status.

Genetics of colon cancer: impact of inheritance on colon cancer risk.

The genes that are mutated in two of the rare syndromes of hereditary colon cancer were recently identified, and genetic diagnosis is already possible in some cases. Acquired mutations of these same genes also appear to be important in sporadic colon cancers. Familial clustering of sporadic cases is common and may likewise arise from inherited susceptibility. Screening strategies for both the rare syndromes and the common cases of colon cancer with familial risk have been suggested. Certain clinical features allow stratification of colon cancer risk among common cases. It is anticipated that continued genetic investigation will result in more precise screening and improved diagnostic and therapeutic options for colon cancer.

Colorectal cancers of rare histologic types compared with adenocarcinomas.

PURPOSE: To examine clinical characteristics of colorectal cancers of rare histologic types compared with adenocarcinomas. METHODS: Review of a population-based registry with complete ascertainment. RESULTS: There were 7,422 colorectal cancers, 4,900 (66 percent) colonic and 2,522 (34 percent) rectal. Two hundred fifty-five cancers (3 percent) were of nonadenocarcinoma varieties including 75 (33 percent) squamous, 74 (33 percent) malignant carcinoids, 37 (16 percent) transitional cell-like, 25 (11 percent) lymphomas, 9 (4 percent) sarcomas, and 2 (0.9 percent) melanomas. Sixty (1.2 percent) of the colon cancers occurred in the appendix, and proportionately more carcinoids accounted for these tumors. Compared with adenocarcinomas, colonic and rectal carcinoids and colonic lymphomas accounted for a larger proportion of cancers in the younger age groups. The elderly had proportionately fewer colonic carcinoids. Colonic carcinoids, rectal squamous-cell cancers, and rectal transitional cell-like cancers were more common in women. Colonic lymphomas had a worse prognosis than adenocarcinomas. Survival was better with colonic and rectal carcinoids and rectal transitional cell-like cancers than with adenocarcinomas. CONCLUSIONS: Colorectal cancers of histologic varieties other than adenocarcinoma have distinctive epidemiologic and clinical traits.

Colonic polyps in an unselected population: prevalence, characteristics, and associations.

OBJECTIVES: To provide a proctosigmoidoscopic review of a very large set of unselected control subjects, providing an unbiased view of colonic polyps in the general population. METHODS: Sigmoidoscopic data from 406 sequentially recruited subjects were analyzed. Participation rates were over 85%, and subjects were thus free of the usual selection bias. RESULTS: Thirty-eight percent of screened individuals were found to have distal colonic polyps. Adenomas were found in 12%, and hyperplastic polyps were found in 30% of screened individuals. Adenomas were more prevalent in males and in older individuals. Hyperplastic prevalence did not differ significantly by gender or age. Synchronous adenomatous and hyperplastic polyps occurred in 3% of screened individuals, but these lesions were not associated. CONCLUSIONS: Distal colonic adenomatous and hyperplastic polyps are very common in the general population and are not associated. The high frequency of these polyps raises questions about the feasibility of biopsy for all polyps, and suggests that further study is needed to determine the appropriate indications for subsequent colonoscopy.

Endoscopic balloon dilation for ulcer-induced gastric outlet obstruction.

OBJECTIVE: To determine the safety and efficacy of endoscopic balloon dilation for ulcer-induced gastric outlet strictures. METHODS: Review of the cumulative experience from two institutions involving 30 patients who underwent endoscopic balloon dilation for peptic ulcer-induced gastric outlet obstruction. Follow-up was by standardized interview at a mean of 15 months (range 4-28 months). RESULTS: Symptoms occurred for an average of 6 months before dilation and included weight loss, epigastric pain, nausea, vomiting, early satiety, bloating, and anorexia. Gastric outlet strictures had a median diameter of 6 mm (range, 0-10 mm). Ten (33%) patients had active ulcers. Six-millimeter to 18-mm (median 15-mm) balloons were inflated a median of 2 times (range 1-4 times) for a median of 60 s (range 30-180 s). Fifty-one procedures (1.7/patient) were performed; 20 (67%) patients had one treatment and 10 (33%) had multiple treatments. Twenty-four (80%) patients achieved sustained symptom relief, 17 of 20 having a single procedure and 7 of 10 required multiple sessions. Dilation failed in 4 (13%) patients with long duodenal strictures. Two (6.7%) patients dilated to 18 mm suffered perforation. Both recovered uneventfully after surgery. CONCLUSIONS: Endoscopic balloon dilation is safe and effective for most patients with ulcer-induced gastric outlet obstruction.

Small bowel cancer: epidemiological and clinical characteristics from a population-based registry.

OBJECTIVES: Data on small bowel cancers are scarce, and are derived primarily from hospital series. Our aim was to examine the epidemiological and clinical characteristics of these rare cancers. The database is population-based registry with complete ascertainment. It is thus free of the selection bias innate to hospital series. METHODS: Review of the Utah Cancer Registry for all small bowel cancers from 1966 through 1990. For comparison, other cancers were reviewed for incidence and relative survival rates. RESULTS: There were 328 small bowel cancers, including 136 (41%) carcinoids, 80 (24%) adenocarcinomas, 72 (22%) lymphomas, 36 (11%) sarcomas, and four (1%) unclassified. The overall age-adjusted incidence per 100,000 was 1.4 for small bowel cancers compared to 35.7 for colorectum and 92.9 for breast. Small bowel cancers occurred most frequently in the sixth and seventh decades of life, and were more common in men. Carcinoids, lymphomas, and sarcomas occurred in order of decreasing frequently in the ileum, jejunum, and duodenum; the reverse was true for adenocarcinomas. Distant metastases occurred in 35 (27%) carcinoids, 14 (28%) adenocarcinomas, 17 (26%) lymphomas, and 10 (33%) sarcomas. Surgery was the primary form of therapy in 108 (79%) carcinoid patients, 80 (49%) adenocarcinoma patients, 52 (72%) lymphoma patients, and 26 (72%) sarcoma patients. The overall 5-year relative survival rate for small bowel cancers was 54%; 83% for carcinoids, 25% for adenocarcinomas, 62% for lymphomas, and 45% for sarcomas. Overall survival, compared to other cancer sites, was surpassed only by cancers of the prostate, breast, and colorectum. CONCLUSIONS: Small bowel cancers consist of several types of rare tumors, each with unique characteristics. The overall prognosis is better than for most common cancers.

Argon laser therapy for hemorrhagic radiation proctitis: long-term results.

In chronic radiation proctitis bleeding occurs from mucosal friability and neovascular telangiectasias. Fourteen patients with bleeding from chronic radiation proctitis underwent endoscopic argon laser therapy at 4 to 8 W. The goal of treatment was obliteration of all telangiectasias. The average follow-up was 35 months. Of the 51 procedures, 48 (94%) were performed on outpatients with enema preparation and little or no sedation. A median of three procedures was performed per patient, with two sessions required for initial control of bleeding. Ten patients (71%) required maintenance therapy for recurrent bleeding from telangiectasias that developed after initial therapy. The mean interval between maintenance sessions was 7 months. No immediate or late complications occurred.

Sigmoidoscopy training for nurses and resident physicians.

Five gastrointestinal nurses (three licensed practical nurses and two registered nurses) and five resident physicians were enrolled in a sigmoidoscopy training protocol. Patients referred for a screening sigmoidoscopy were randomized to have the procedure performed by a nurse or a resident. Objective criteria for proficiency were depth of endoscope insertion, procedure time, and identification of anatomic landmarks and pathologic lesions; subjective criteria included thoroughness and the need for assistance. Four nurses and all of the residents were deemed proficient at a mean of 20 procedures in both groups. One registered nurse did not achieve proficiency after 35 procedures; this determination was based on subjective criteria. Insertion depth and identification of normal anatomy improved with experience. Trainees missed 1.4% of pathologic lesions, and no complications were observed. Nurses can be trained to perform a screening sigmoidoscopy in a safe and effective manner, with results similar to those for doctors.

Dysgonic fermenter-3: a bacterium associated with diarrhea in immunocompromised hosts.

We describe two patients with chronic diarrhea associated with dysgonic fermenter-3 (DF-3) infection. One patient had common variable hypogammaglobulinemia and the other hand chronic idiopathic neutropenia and human immunodeficiency virus infection. Specific stool culture techniques were necessary to isolate DF-3. The organism was sensitive to clindamycin, tetracycline, and trimethoprim-sulfamethoxazole. Antibiotic therapy eradicated the organism and the diarrhea resolved in both patients. DF-3 is a little-recognized organism associated with diarrhea in the immunocompromised patient. It should be suspected when routine evaluation and stool cultures are not diagnostic.

Hereditary aspects of colorectal adenomas.

BACKGROUND: Inheritance is important to the development of colonic adenomatous polyps and colon cancer. Current knowledge of inherited susceptibility to colonic neoplasms suggests that colon cancer screening strategies should consider familial and genetic risk. METHODS: This report reviews the literature pertinent to adenomatous polyp and colon cancer inheritance and suggests polyp-cancer screening procedures based on inherited or familial risk. RESULTS: Colorectal adenomas and cancer occur in several rare inherited syndromes and more commonly as sporadic cases. Intensive screening protocols have been suggested for the inherited syndromes because of the high associated cancer risk. Recent evidence suggests that inherited susceptibility also may be important in a large fraction of the so-called sporadic cases. Preliminary screening guidelines are suggested for this category based on the number of first-degree relatives affected with colon cancer. CONCLUSIONS: Inherited susceptibility appears to be more important to the pathogenesis of colorectal adenomas and cancer than previously recognized. Screening strategies which consider inherited risk may increase the effectiveness of cancer detection and prevention.