Low frequency of colorectal dysplasia in patients with long-standing inflammatory bowel disease colitis: detection by fluorescence endoscopy

Endoscopic visualization of cancer and dysplasia in patients with ulcerative colitis following sensitization with oral 5-aminolevulinic acid

OBJECTIVE

Early diagnosis of colitis-associated cancer and dysplasia through surveillance endoscopy is vital for patients with ulcerative colitis (UC). This study aimed to evaluate the efficacy of autofluorescence endoscopy (AFE) using 5-aminolevulinic acid (ALA) and to investigate the fluorescence signal localization pattern following 5-ALA administration in tumorous lesions diagnosed as colitis-associated cancer and dysplasia. The sensitivity and specificity of tumorous lesions detected by white light endoscopy (WLE) with and without AFE were evaluated.

METHODS

Overall, 13 endoscopic procedures were performed in 11 patients with UC using WLE and AFE following the oral administration of 5-ALA. The biopsied lesions detected via endoscopy and resected specimens from cases underwent colectomy were assessed histopathologically. The sensitivity and specificity of detecting tumorous lesions by WLE with and without AFE were evaluated.

RESULTS

Of the 68 lesions detected and biopsied, 63 were detected via WLE, and five were detected via AFE alone. The sensitivity of detecting colitis-associated cancer and dysplasia via WLE combined with AFE was 36.4%, and the specificity, positive predictive value and negative predictive value were 94.2%, 57.1%, and 87.5%, respectively. Tumorous lesions displayed three types of fluorescence patterns on AFE.

CONCLUSIONS

AFE using 5-ALA can detect colitis-associated cancer and dysplasia in patients with long-standing UC and lesions that could not be detected via WLE. The distinctive fluorescence patterns in lesions may permit qualitative diagnoses of colitis-associated cancer and dysplasia.

Modern Endoscopic Imaging in Diagnosis and Surveillance of Inflammatory Bowel Disease Patients

Endoscopy remains the most important diagnostic and monitoring modality in the management of inflammatory bowel disease. Advances in imaging have progressively added new tools into the armamentarium of endoscopists with the goal of more accurate, sensitive, and accessible visual diagnoses for the benefit of patients with gastrointestinal diseases. Here, we review the relevant literature regarding commonly used endoscopic techniques (dye-based and digital chromoendoscopy, high-definition endoscopy, capsule endoscopy, and endosonography), as well as advanced and experimental technologies (full-spectrum endoscopy, endocytoscopy, autofluorescence, laser endoscopy, and endomicroscopy, including molecular imaging), applicable to inflammatory bowel diseases and emerging for implementation into everyday practice. Additionally, we discuss future directions and techniques as candidates for a superior inflammation imaging in the diagnosis and prediction of therapeutic response.

Advanced endoscopy imaging in inflammatory bowel diseases

BACKGROUND AND AIMS

Rapid assessment of mucosal inflammation is of crucial importance for the initial diagnosis and the assessment of mucosal healing in inflammatory bowel disease (IBD). Moreover, the identification of intraepithelial neoplasias in IBD is of key relevance for clinical management. Here, we systematically analyzed the utility of advanced endoscopic imaging techniques for optimized diagnosis in IBD.

METHODS

PubMed/Medline, Web of Knowledge, and Cochrane library were searched twice for diagnostic studies on advanced endoscopic imaging in IBD. Clinical and technical information was retrieved and subsequently analyzed. Main outcome parameters consisted of the quality of the results, adverse events, and diagnostic yield.

RESULTS

Fifty-six clinical studies with a total of 3296 patients were selected for final analysis. Filter technologies permitted a more detailed analysis of mucosal inflammation in IBD. In spite of substantial heterogeneity across studies, dye-based chromoendoscopy with targeted biopsy sampling yielded higher detection rates of intraepithelial neoplasias in ulcerative colitis as compared with white-light endoscopy with random biopsy sampling. Moreover, endocytoscopy and endomicroscopy allowed subsurface imaging of inflamed or neoplastic mucosa in IBD at subcellular resolution. Finally, endomicroscopy-aided molecular imaging enabled the identification of membrane-bound tumor necrosis factor on mucosal cells as a potential driver of disease activity in Crohn's disease. No relevant adverse events were reported.

CONCLUSIONS

Advanced endoscopic imaging technologies are feasible, safe, and partially effective tools for detailed diagnosis of mucosal inflammation and detection of neoplasias in IBD. Results obtained from these advanced techniques may provide a rational basis for individualized, optimized therapy for IBD patients.

The role of endoscopy in inflammatory bowel disease

Inflammatory bowel disease (IBD) is a group of chronic immune-mediated disorders of the gastrointestinal tract. It is often the result of the interaction of genetic and environmental factors. The role of endoscopy in disease surveillance is unprecedented. However, there is considerable debate in therapeutic goals in IBD patients, ranging from the resolution of clinical symptoms to mucosal healing. Furthermore, deep remission has recently been advocated for altering disease course in these patients. Additionally, neoplasia continues to be a significant cause of morbidity and mortality in IBD patients. This review discussed the role of several endoscopic techniques in assessing mucosal healing and neoplasia with emphasis on novel non-invasive endoscopic techniques.

Is it possible to discriminate between neoplastic and nonneoplastic lesions in ulcerative colitis by magnifying colonoscopy?

BACKGROUND

Colitis-associated cancer/dysplasia is an intestinal tract condition that can affect the life expectancy of patients with ulcerative colitis. It is often difficult to detect neoplastic lesions. This study evaluated whether any endoscopic features are effective for distinguishing colitis-associated cancer/dysplasia from nonneoplastic lesions in patients with ulcerative colitis.

METHODS

The study involved 52 patients with 61 lesions treated at Hiroshima University Hospital between September 1999 and May 2012: 10 patients with 11 dysplastic lesions, 5 patients with 5 intramucosal carcinomas, 3 patients with 3 submucosal carcinomas, and 34 patients with 42 nonneoplastic lesions. All patients had undergone targeted biopsy. Endoscopic findings were compared between patients with biopsy-determined neoplasia and those with biopsy-determined nonneoplasia. Multivariate regression analysis was performed to identify magnifying chromocolonoscopy features predictive of neoplasia.

RESULTS

No significant difference was found in conventional endoscopy features between the neoplastic and nonneoplastic lesions. Under magnifying chromocolonoscopy, the pit density of the neoplastic lesions was found to be significantly greater than that of the nonneoplastic lesions (89% [17/19] versus 60% [25/42], respectively). Pit margins were more frequently irregular in the neoplastic lesions than in the nonneoplastic lesions (63% [12/19] versus 33% [14/42], respectively).

CONCLUSIONS

In differentiating between colitis-associated neoplastic and nonneoplastic lesions, focus should be on the high residual density of pits and irregular pit margins observed under magnifying chromocolonoscopy.

Advanced endoscopic imaging for surveillance for dysplasia and colorectal cancer in inflammatory bowel disease: could the pathologist be further helped?

Patients with inflammatory bowel disease (IBD) have an increased risk of developing intestinal cancer. The magnitude of that increased risk as well as how best to mitigate it remain a topic of ongoing investigation in the field. It is important to quantify the risk of colorectal cancer in association with IBD. The reported risk varies widely between studies. This is partly due to the different methodologies used in the studies. Because of the limitations of surveillance strategies based on the detection of dysplasia, advanced endoscopic imaging and techniques involving the detection of alterations in mucosal antigens and genetic abnormalities are being investigated. Development of new biomarkers, predicting future occurrence of colonic neoplasia may lead to more biomarker-based surveillance. There are promising results that may lead to more efficient surveillance in IBD patients and more general acceptance of its use. A multidisciplinary approach, involving in particular endoscopists and pathologists, together with a centralized patient management, could help to optimize treatments and follow-up measures, both of which could help to reduce the IBD-associated cancer risk.

Cancer prevention in ulcerative colitis: long-term outcome following fluorescence-guided colonoscopy

BACKGROUND

Patients with long-standing ulcerative colitis require repeated endoscopies for early detection of neoplasias, which, however, are frequently missed by standard colonoscopy. Fluorescence-guided colonoscopy is known to improve the detection rate but the long-term effects of fluorescence-guided colonoscopy are unknown.

METHODS

Colitis patients with negative findings at index fluorescence-guided colonoscopy entered a prospective long-term study with conventional colonoscopies at 2-year intervals. Risk and time to progression were evaluated. The positive predictive value was assessed in patients with neoplasias at index fluorescence-guided colonoscopy who underwent immediate total colectomy.

RESULTS

Thirty-one patients with negative fluorescence-guided colonoscopy were surveyed for a mean of 7.8 ± 0.9 years. Neoplasia was observed in only two of them (6%) after 7 and 8 years of follow-up, respectively. Neoplasia at index fluorescence-guided colonoscopy was observed in 10 patients. In all of them, multiple flat low-grade intraepithelial neoplasia was diagnosed. At immediate colectomy performed in eight of them, the diagnosis of flat low-grade intraepithelial neoplasia was confirmed, corresponding to a positive predictive value of 100%. However, synchronous more advanced neoplasia was detected in three of the eight patients (38%). All patients, those with and those without neoplasia, were alive at the end of the study.

CONCLUSIONS

Fluorescence-guided colonoscopy misses, in contrast to standard colonoscopy, few, if any, patients with neoplasia. Most neoplasia-negative patients remain negative during prolonged follow-up. However, when low-grade dysplasia is diagnosed by fluorescence-guided colonoscopy, colectomy is recommended because more than a third of the patients harbor synchronous, more advanced neoplasia.

Cytomegalovirus disease, haemophagocytic syndrome, immunosuppression in patients with IBD: 'a cocktail best avoided, not stirred'

We report two cases of cytomegalovirus (CMV) viraemia resulting in severe pneumonitis and associated haemophagocytic syndrome manifesting in patients with inflammatory bowel disease, on stable doses of azathioprine in clinical remission. In both cases, azathioprine was withdrawn at time of hospital presentation and after delays in diagnosis; intravenous ganciclovir was then administered, with resultant rapid improvement of haematological and clinical parameters. Following recovery, immunomodulators were not recommenced given patient aversion and the theoretical risk of CMV reactivation, albeit the evidence for this approach is limited. CMV-related haemophagocytic syndrome and organ dysfunction, in the context of immunomodulator therapy in IBD are rare but life-threatening, and thus requires further investigation and discussion.

Non-polypoid colorectal neoplasms in ulcerative colitis

The incidence of colorectal cancer associated with ulcerative colitis (UC) increases with time. It is imperative to identify dysplasia-associated lesions or masses (DALM) and non-polypoid colorectal neoplasms (NP-CRN) to reduce the morbidity and mortality from colorectal cancer associated with UC. Recent findings suggest most dysplastic lesions in UC can be considered as visible under careful endoscopic observation. To find NP-CRN in UC, the careful examination of well-prepared mucosa and noting subtle differences is necessary. Magnifying chromoendoscopy, therefore, can be useful to endoscopically diagnose these subtle findings. The authors believe that targeted biopsies during chromoendoscopy will increasingly be used and replace random biopsies in the future.

Time-gated fluorescence spectroscopy improves endoscopic detection of low-grade dysplasia in ulcerative colitis

BACKGROUND

Dysplasia in ulcerative colitis is frequently missed with 4-quadrant biopsies. An experimental setup recording delayed fluorescence spectra simultaneously with white light endoscopy was recently developed.

OBJECTIVE

We compared detection of invisible flat intraepithelial neoplasia with protoporphyrin IX fluorescence and standard 4-quadrant biopsies.

DESIGN

Prospective, crossover design without randomization of the order of procedures.

SETTING

Gastroenterology Department, Humboldt University, Charité, Berlin, Germany.

PATIENTS

Forty-two patients with extensive ulcerative colitis of more than 10 years' duration were included.

INTERVENTIONS

Colonoscopy with 4-quadrant biopsies and targeted biopsies of macroscopic lesions and time-gated fluorescence-guided colonoscopy were performed 2 weeks apart by 2 blinded endoscopists. Three independent pathologists examined the biopsy specimens.

MAIN OUTCOME MEASUREMENTS

The primary outcome criterion was detection rate of invisible flat intraepithelial neoplasia.

RESULTS

Invisible flat intraepithelial neoplasia was detected in 3 (7%) patients by white light 4-quadrant biopsies and in 10 (24%) patients by fluorescence-guided endoscopy (P = .02). The sensitivity and specificity for differentiating patients with and without dysplasia were 100% and 81%, respectively. Dysplastic and nondysplastic mucosa could be discriminated with a sensitivity and specificity of 73% and 81%, respectively.

LIMITATIONS

The trial was not randomized.

CONCLUSION

The detection rate of intraepithelial neoplasia in patients with ulcerative colitis can be improved by fluorescence-guided colonoscopy.

Application of laser induced auto-fluorescence spectrum in the diagnosis of cancer

Along with the development of cross-discipline of the fluorescence (physics) and medicine, laser induced auto-fluorescence spectrum integrated with endoscopic technique became a new way to diagnose cancer in recent years. It is sensitive and non-invasive. In this review, we discuss the mechanism, clinical application and development tendency of laser induced auto-fluorescence spectrum.

Cancer in inflammatory bowel disease

Patients with long-standing inflammatory bowel disease (IBD) have an increased risk of developing colorectal cancer (CRC). Many of the molecular alterations responsible for sporadic colorectal cancer, namely chromosomal instability, microsatellite instability, and hypermethylation, also play a role in colitis-associated colon carcinogenesis. Colon cancer risk in inflammatory bowel disease increases with longer duration of colitis, greater anatomic extent of colitis, the presence of primary sclerosing cholangitis, family history of CRC and degree of inflammation of the bowel. Chemoprevention includes aminosalicylates, ursodeoxycholic acid, and possibly folic acid and statins. To reduce CRC mortality in IBD, colonoscopic surveillance with random biopsies remains the major way to detect early mucosal dysplasia. When dysplasia is confirmed, proctocolectomy is considered for these patients. Patients with small intestinal Crohn's disease are at increased risk of small bowel adenocarcinoma. Ulcerative colitis patients with total proctocolectomy and ileal pouch anal-anastomosis have a rather low risk of dysplasia in the ileal pouch, but the anal transition zone should be monitored periodically. Other extra intestinal cancers, such as hepatobiliary and hematopoietic cancer, have shown variable incidence rates. New endoscopic and molecular screening approaches may further refine our current surveillance guidelines and our understanding of the natural history of dysplasia.

Cancer in inflammatory bowel disease

Patients with long-standing inflammatory bowel disease (IBD) have an increased risk of developing colorectal cancer (CRC). Many of the molecular alterations responsible for sporadic colorectal cancer, namely chromosomal instability, microsatellite instability, and hypermethylation, also play a role in colitis-associated colon carcinogenesis. Colon cancer risk in inflammatory bowel disease increases with longer duration of colitis, greater anatomic extent of colitis, the presence of primary sclerosing cholangitis, family history of CRC and degree of inflammation of the bowel. Chemoprevention includes aminosalicylates, ursodeoxycholic acid, and possibly folic acid and statins. To reduce CRC mortality in IBD, colonoscopic surveillance with random biopsies remains the major way to detect early mucosal dysplasia. When dysplasia is confirmed, proctocolectomy is considered for these patients. Patients with small intestinal Crohn’s disease are at increased risk of small bowel adenocarcinoma. Ulcerative colitis patients with total proctocolectomy and ileal pouch anal-anastomosis have a rather low risk of dysplasia in the ileal pouch, but the anal transition zone should be monitored periodically. Other extra intestinal cancers, such as hepatobiliary and hematopoietic cancer, have shown variable incidence rates. New endoscopic and molecular screening approaches may further refine our current surveillance guidelines and our understanding of the natural history of dysplasia.

Recent advances of endoscopy in inflammatory bowel diseases

Endoscopy plays a key role in the diagnosis and treatment in inflammatory bowel disease (IBD). The most valuable tool for distinguishing different types of IBD is a complete ileocolonoscopy with mucosal biopsy. Endoscopic localization of the disease not only aids in determining prognosis and appropriateness of medical therapies but also aids decision-making in those undergoing surgical therapy. With regard to therapeutic applications, obstructive symptoms caused by benign fibrotic strictures can be treated adequately by endoscopic balloon dilation. Epidemiological studies have demonstrated an increased risk of colorectal cancer in patients with both ulcerative colitis and colonic Crohn's disease (CD). Colonoscopy is currently considered to be the gold standard for cancer surveillance. Published guidelines recommend that two to four biopsy samples should be obtained every 10 cm in the colorectum, necessitating 20-50 samplings per examination. This may result in standard colonoscopy - which is also very time-consuming and laborious - missing significant numbers of small lesions. Various novel techniques have been applied to reduce the required number of biopsy samples and the duration of examinations, including chromoendoscopy with or without magnification, fluorescence endoscopy, narrow-band imaging, optical coherence tomography, and confocal laser endomicroscopy. Until recently the only way to evaluate the small-bowel mucosa in a patient with CD was by barium small-bowel radiographs and intubation of the distal terminal ileum. Both wireless-capsule endoscopy (WCE) and double-balloon enteroscopy (DBE) allow light to be used in the inspection of the small bowel and may replace radiological methods. WCE is more convenient than DBE for probing small-bowel mucosal changes, but only DBE allows a biopsy sample to be obtained from the deep small bowel, and these two examinations can be considered complementary. The wider application of new techniques in the near future might increase the role played by endoscopy in the management of IBD.

Magnifying colonoscopy with narrow band imaging system for the diagnosis of dysplasia in ulcerative colitis: a pilot study

BACKGROUND

Narrow-band imaging (NBI) is a novel illumination technology for endoscopy that enhances vasculature of the GI tract.

OBJECTIVE

The aim was to elucidate whether NBI colonoscopy can identify dysplasia in patients with ulcerative colitis (UC).

DESIGN

Cross-sectional study of eligible patients.

SETTING

Single center.

PATIENTS

46 patients with UC.

INTERVENTIONS

Apparently flat mucosa at each segment and visible protruding lesions were observed by magnifying NBI colonoscopy. The surface structure was classified into honeycomb-like, villous, or tortuous pattern. The grade of dysplasia was determined in the specimens obtained from protrusions and from flat mucosa.

MAIN OUTCOME MEASUREMENTS

The positive predictive value of conventional and NBI colonoscopy for the diagnosis of dysplasia.

RESULTS

A total of 296 sites (20 protruding lesions and 276 flat areas) were examined by NBI colonoscopy. The surface pattern was determined to be honeycomb like in 161 sites, villous in 85 sites, and tortuous in 50 sites. Five dysplastic lesions were detected in 3 patients. A patient had 3 dysplastic lesions and the other 2 had a dysplastic lesion each. The positive rate of dysplasia was higher in protrusions (2/20 sites, 10%) than in flat mucosa (3/276 sites, 1.1%, P = .038; however, correction for the multiple testing of data removes this significance). When the surface pattern was taken into account, the rate of positive dysplasia was higher in the tortuous pattern (4/50 sites, 8%) than in the honeycomb-like or villous patterns (1/246 sites, 0.4%, P = .003).

LIMITATIONS

Uncontrolled study.

CONCLUSIONS

The tortuous pattern determined by NBI colonoscopy may be a clue for the identification of dysplasia during surveillance for UC.