Detection of nonpolypoid colorectal neoplasia using magnifying endoscopy in colonic inflammatory bowel disease

Characteristics and Prognosis of Sporadic Neoplasias Detected in Patients with Ulcerative Colitis

INTRODUCTION

Patients with ulcerative colitis (UC) develop not only UC-associated neoplasias but also sporadic neoplasias (SNs). However, few studies have described the characteristics of SNs in patients with UC. Therefore, this study aimed to evaluate the clinical features and prognosis of SNs in patients with UC.

METHODS

A total of 141 SNs in 59 patients with UC, detected by surveillance colonoscopy at Hiroshima University Hospital between January 1999 and December 2021, were included. SNs were diagnosed based on their location, endoscopic features, and histopathologic findings along with immunohistochemical staining for Ki67 and p53.

RESULTS

Of the SNs, 91.5% were diagnosed as adenoma and 8.5% were diagnosed as carcinoma (Tis carcinoma, 3.5%; T1 carcinoma, 5.0%). 61.0% of the SNs were located in the right colon, 31.2% were located in the left colon, and 7.8% were located in the rectum. When classified based on the site of the lesion, 70.9% of SNs occurred outside and 29.1% within the affected area. Of all SNs included, 95.7% were endoscopically resected and 4.3% were surgically resected. Among the 59 patients included, synchronous SNs occurred in 23.7% and metachronous multiple SNs occurred in 40.7% during surveillance. The 5-year cumulative incidence of metachronous multiple SNs was higher in patients with synchronous multiple SNs (54.2%) than in those without synchronous multiple SNs (46.4%).

CONCLUSION

Patients with UC with synchronous multiple SNs are at a higher risk of developing metachronous multiple SNs and may require a closer follow-up by total colonoscopy than patients without synchronous SNs.

Artificial intelligence-assisted endoscopy changes the definition of mucosal healing in ulcerative colitis

The relevance of endoscopic monitoring of ulcerative colitis (UC) has been translated into the new concept of "mucosal healing (MH)" as the therapeutic goal to achieve because a large amount of scientific data have revealed the favorable prognostic value of a healed mucosa in determining the clinical outcome of UC. Recent interest in MH has skewed toward not only endoscopic remission but also histological improvement (so called histological MH). However, we should recognize that there have been no prospectively validated endoscopic scoring systems of UC activity in previous clinical trials. Artificial intelligence (AI)-assisted endoscopy has been developed for gastrointestinal cancer surveillance. Recently, several AI-assisted endoscopic systems have been developed for assessment of MH in UC. In the future, the development of a new endoscopic scoring system based on AI might standardize the definition of MH. Therefore, "The road to an exact definition of MH in the treatment of UC has begun only now".

Clinical usefulness of linked color imaging for evaluation of endoscopic activity and prediction of relapse in ulcerative colitis

PURPOSE

In the treatment of ulcerative colitis (UC), accurate evaluation of UC activity is important to achieve mucosal healing. We sought to investigate the clinical utility of linked color imaging (LCI) for the evaluation of endoscopic activity and prediction of relapse in UC patients.

METHODS

We enrolled 72 consecutive UC patients in remission who underwent colonoscopy at our institution between September 2016 and October 2018. The relationship between the presence of redness in white light imaging (WLI) and LCI and histopathological inflammation (Geboes score: GS) at 238 biopsy sites was examined. We also assessed the presence or absence of planar redness in the entire rectum as ± and classified the patients into three groups according to the combination of WLI/LCI: A: WLI-/LCI-, B: WLI-/LCI+, and C: WLI+/LCI+. The relationship between WLI/LCI classification and relapse in 64 patients followed up for more than 12 months from initial colonoscopy was assessed and compared to the Mayo endoscopic subscore (MES).

RESULTS

A GS of 0 or 1 accounted for 89% of WLI/LCI non-redness sites, while a GS of 2 or 3 accounted for 42% of WLI non-redness/LCI redness sites. LCI findings were significantly correlated with GS. During follow-up, 10 patients in group C and four patients in group B relapsed, but none in group A. Non-relapse rates were significantly correlated with WLI/LCI classification, but not with MES.

CONCLUSION

LCI is a useful modality for accurate assessment of endoscopic activity and prediction of relapse in UC by detecting mild inflammation unrecognizable by WLI.

Genomic Landscape of Early-stage Colorectal Neoplasia Developing From the Ulcerative Colitis Mucosa in the Japanese Population

BACKGROUNDS

Colorectal neoplasias (CRN)s developing from the ulcerative colitis (UC) mucosa include both colitic and sporadic neoplasias. Although several genomic analyses of advanced colitis-associated cancer are available, such studies do not distinguish between colitic and sporadic cases, and the early-stage genomic alterations involved in the onset of colitic cancer remain unclear. To address this, we performed a genomic analysis of early-stage CRN developing from the UC mucosa (CRNUC).

METHODS

We extracted DNA from 36 early-stage CRNUCs (T1 cancer, 10; dysplasia, 26) from 32 UC patients and performed targeted sequencing of 43 genes commonly associated with colitis-associated cancer and compared the results with sequencing data from the Japanese invasive colitis-associated cancer.

RESULTS

The most frequently mutated gene in the CRNUC cohort was APC (mutated in 47.2% of the cases), followed by TP53 (44.4%), KRAS (27.8%), and PRKDC (27.8%). None of the TP53 mutations occurred at any of the hotspot codons. Although the TP53 mutations in The Cancer Genome Atlas of Colorectal Cancer were dispersed throughout the gene, those detected here in CRNUC cases were concentrated in the amino terminal part of the DNA-binding domain. Interestingly, the mutations in KRAS and TP53 were mutually exclusive in CRNUC, and CRNUCs with KRAS mutations had histologically serrated lesions in the gland duct. Mayo endoscopic subscore was higher in TP53-mutated CRNUCs and lower in KRAS-mutated CRNUCs.

CONCLUSIONS

Our findings suggest that early-stage CRNUC can be classified into 2 groups: those developing through the carcinogenic pathway via TP53 mutations and those developing through the carcinogenic pathway via KRAS mutations.

Clinical usefulness of magnifying colonoscopy for the diagnosis of ulcerative colitis-associated neoplasia

BACKGROUND AND AIM

The aim of this investigation was to evaluate the efficacy of Japanese magnifying colonoscopic classifications for ulcerative colitis-associated neoplasia (UCAN).

METHODS

We reviewed the colonoscopy records from 2011 to 2018 at our institutions and identified cases of endoscopically or surgically resected UCAN observed by magnifying narrow-band imaging (NBI) endoscopy and magnifying chromoendoscopy. Association between magnifying endoscopic classification and histopathological findings was investigated retrospectively. Japan NBI expert team (JNET) classification and pit pattern classification were applied.

RESULTS

There were 17 patients who had a diagnosis of UCAN. Tumors of types 2A, 2B and 3 by JNET classification correlated with the histopathological findings of low-grade dysplasia (LGD)/high-grade dysplasia (HGD), HGD, and massively submucosal invasive (mSM) carcinoma, respectively. Tumors of types III/IV, V_I low irregularity, and V_I high irregularity/V_N by pit pattern classification were correlated with the histopathological findings of LGD/HGD, HGD, and mSM carcinoma, respectively.

CONCLUSIONS

Japan NBI expert team classification and pit pattern classification may be predictive of the histological diagnosis and invasion depth of UCAN. This needs to be investigated prospectively in a large cohort or in a randomized clinical trial.

Early detection of ulcerative colitis-associated colorectal cancer

Colitis-associated colorectal cancer (CACC) is one of the most serious complications of inflammatory bowel disease (IBD), particularly in ulcerative colitis (UC); it accounts for approximately 15% of all-causes mortality among IBD patients. Because CACC shows a worse prognosis and higher mortality than sporadic colorectal cancer, early detection is critical. Colonoscopy is primarily recommended for surveillance and several advanced endoscopic imaging techniques are emerging. In addition, recent studies have reported on attempts to develop clinically relevant biomarkers for surveillance using various biosamples, which may become high-performance screening tools in the future, so the best approach and technique for cancer surveillance in long-standing UC patients remain under debate. This review gives a comprehensive description and summary about what progress has been made in terms of early CACC detection.

Endoscopic morphologic features of ulcerative colitis-associated dysplasia classified according to the SCENIC consensus statement

BACKGROUND AND AIMS

Recent advances in endoscopic equipment and diagnostic techniques have made possible the detection of early dysplasia in the inflamed mucosa of ulcerative colitis (UC). The SCENIC consensus statement recommends the use of unified terminology for the morphology of dysplasia. In this study, we investigated the endoscopic features of high-grade dysplasia (HGD) in a clinical setting.

METHODS

We retrospectively identified 62 patients with UC who were diagnosed with colitis-associated cancer or HGD between 1997 and 2015. A total of 39 lesions of HGD detected by targeted biopsy sampling in 31 patients were reviewed, and the endoscopic morphology was classified according to the SCENIC guidelines.

RESULTS

In total, 0 (0%), 6 (15.4%), 19 (48.7%), 12 (30.8%), and 2 (5.1%) lesions with HGD were classified as pedunculated, sessile, superficial elevated, flat, and depressed, respectively. Nearly 80% of the lesions were located in the rectum or sigmoid colon. All flat and depressed lesions were red in color. Typically, sessile/superficial elevated lesions accompanied a flat area (Is+IIb/IIa+IIb). Ulceration was observed in 2 depressed lesions (5.1%). Although the borders were indistinct in 21 lesions (53.8%) without the use of magnifying colonoscopy, all lesions could be distinguished from the surrounding mucosa using magnifying endoscopy.

CONCLUSIONS

This is the first study to classify the morphologic features of HGD using the SCENIC guidelines in a clinical setting. Based on our findings, endoscopists should recognize that HGD is frequently associated with a flat/superficial elevated area and red discoloration and should inspect particularly carefully in the rectum and sigmoid colon. The findings of chromoendoscopy and magnifying colonoscopy may also be useful in distinguishing lesions from the surrounding mucosa.

Clinical usefulness of narrow band imaging magnifying colonoscopy for assessing ulcerative colitis-associated cancer/dysplasia

Background and study aims: Colitis-associated cancer/dysplasia (CC/D) can affect the life expectancy of patients with ulcerative colitis (UC). Although the utility of magnifying chromocolonoscopy has been shown, the use of optical magnification with narrow band imaging (NBI) for distinguishing CC/D from non-neoplastic lesions in patients with UC has not been reported. We evaluated whether endoscopic findings are distinguishing and thus assessed the clinical usefulness of NBI magnification for differentiating UC-associated lesions. Patients and methods: The study involved 27 patients diagnosed and treated at Hiroshima University Hospital between September 2005 and March 2015: a neoplasia group (16 lesions) and a non-neoplasia group (17 lesions). The neoplasias comprised 9 dysplastic lesions, 5 intramucosal carcinomas, and 2 submucosal carcinomas, and 17 non-neoplastic lesions. Targeted biopsy samples of suspicious lesions detected by conventional colonoscopy were classified pathologically as neoplastic or non-neoplastic, and NBI magnifying colonoscopy findings (i. e., the surface [unclear/regular/irregular/amorphous] and vascular [same as the background mucosa/regular/irregular/avascular] patterns) of the 2 lesion types were compared. Results: Irregular/amorphous surface patterns were significantly more common in neoplastic lesions than in non-neoplastic lesions (81 % [13/16] vs. 18 % [3/17], respectively, P < 0.001). Irregular/avascular vessel pattern tended to be more common in neoplastic lesions (75 % [12/16] vs. 41 % [7/17], respectively). The surface pattern correctly predicted 82 % of neoplastic lesions, and the vessel pattern correctly predicted 67 % of non-neoplastic lesions. The 2 endoscopic findings together correctly predicted 91 % of neoplastic lesions. Conclusion: Surface pattern, determined by magnifying colonoscopy with NBI, is useful for differenting between UC-associated neoplastic and non-neoplastic lesions.

Advances in endoscopic imaging in ulcerative colitis

Modern strategies for the treatment of ulcerative colitis require more accurate tools for gastrointestinal imaging to better assess mucosal disease activity and long-term prognostic clinical outcomes. Recent advances in gastrointestinal luminal endoscopy are radically changing the role of endoscopy in every-day clinical practice and research trials. Advanced endoscopic imaging techniques including high-definition endoscopes, optical magnification endoscopy, and various chromoendoscopy techniques have remarkably improved endoscopic assessment of ulcerative colitis. More recently, optical biopsy techniques with either endocytoscopy or confocal laser endomicroscopy have shown great potential in predicting several histological changes in real time during ongoing endoscopy. Here, we review current applications of advanced endoscopic imaging techniques in ulcerative colitis and present the most promising upcoming headways in this field.

Erythropoietin attenuates intestinal inflammation and promotes tissue regeneration

BACKGROUND

The prevalence of inflammatory bowel disease (IBD) is increasing. Since patients usually need long-term treatment and suffer from reduced quality of life, there is a need to develop new therapeutic strategy. The aim of this study was to investigate the therapeutic potential of erythropoietin (EPO) for the treatment of IBD.

METHODS

Murine colitis was induced by 3.0% Dextran Sulfate Sodium (DSS). Recombinant human EPO (rhEPO) was given to evaluate the anti-inflammatory and regenerative effects on intestinal inflammation. The effect of rhEPO on human colon epithelial cells was also evaluated. Immunohistochemical analysis of EPO receptor was performed in human IBD tissues.

RESULTS

While about 62% of control mice with severe colitis induced by 5-day DSS died, 85% of mice treated with rhEPO survived. Histological analysis confirmed that EPO treatment reduced the colonic inflammation. Furthermore, EPO treatment significantly downregulated the local expressions of IFN-γ, TNF-α and E-selectin in the colon, suggesting that the effect was associated with inhibiting local immune activation. In a 4-day DSS-induced colitis model, rhEPO significantly improved the recovery of body weight loss compared to controls. Furthermore, proliferating cell nuclear antigen expression was significantly upregulated in the colon tissue from mice treated with rhEPO compared to controls. In addition, rhEPO increased the growth of cultured human colon epithelial cells in a dose-dependent manner. Furthermore, EPO-receptor expression was confirmed in human IBD colon tissues.

CONCLUSION

Three major functions of EPO, hematopoiesis, anti-inflammation and regeneration, may produce significant effects on intestinal inflammation, therefore suggesting that rhEPO might be useful for IBD.

Application and Efficacy of Super-Magnifying Endoscopy for the Lower Intestinal Tract

Endoscopy plays a significant role in the diagnosis, management, and surveillance of colorectal cancer (CRC) and inflammatory bowel diseases (IBDs). Moreover, magnifying endoscopy and image-enhanced endoscopy has a crucial role in the clinical setting. Recently, a super-magnifying endoscope has been developed, and two devices, confocal laser endomicroscopy (CLE) and an endocytoscopy system (ECS), which allow in vivo microscopic inspection of the microstructural mucosal features of the gastrointestinal tract, are currently available. Studies on the use of ECS in CRC were reported by a Japanese group. Additionally, a few studies on the use of ECS in IBD have been reported. CLE has been shown to be reliable in assessing the activity of the disease in IBDs in both ulcerative colitis and Crohn’s disease. Various published studies evaluated the use of CLE during colonoscopy to distinguish colorectal polyp pathology and neoplasia. However, these studies are heterogeneous, and further evidence is necessary to confirm the efficacy of CLE.

Clinical usefulness of endocytoscopy in the remission stage of ulcerative colitis: a pilot study

BACKGROUND

Histopathology can be used to detect ulcerative colitis (UC) relapse, but diagnosis of the disease activity by histopathology requires multiple biopsies to be taken. Magnifying endocytoscopy provides a method for real-time ultra-magnifying imaging. It was recently reported that the endocytoscopy system score (ECSS) correlates well with the histopathology of UC. Here we evaluated the clinical usefulness of endocytoscopy for accurately monitoring UC during remission.

METHODS

We performed endocytoscopy on 26 patients with UC in remission that had been diagnosed by conventional colonoscopy at our institution between January and April 2013. Endocytoscopy was performed at the area of the rectum where UC had been detected with conventional endoscopy. Biopsies were also taken from the same area and histopathology was evaluated by a single pathologist according to the Matts' grading system. The correlation between the relapse rate of UC and both the ECSS and the Matts' histopathological grade was evaluated.

RESULTS

The ECSS of the intestinal mucosa in UC showed a correlation with the Matts' histopathological grade (Spearman's |r| = 0.647). The patients were classified into two groups: those with an ECSS of 0-2 (Grade A, 12 cases) and those with an ECSS of 3-6 (Grade B, 10 cases). To date, three Grade B cases have relapsed and no Grade A cases have relapsed. The average post-endocytoscopy surveillance period was 446 ± 92 days.

CONCLUSIONS

The ECSS may be a predictive indicator for UC relapse since there was a correlation between the ECSS and the degree of inflammation as determined by histopathology.

Differential Diagnosis of Colonic Strictures: Pictorial Review with Illustrations from Computed Tomography Colonography

Strictures of the colon can lead to significant morbidity requiring surgical management. The etiology of strictures is broad and generally categorized as benign, malignant, or pseudostrictures. Computed tomography (CT) is a crucial imaging modality in the assessment and characterization of colonic pathologies but colonoscopy remains the diagnostic gold standard. However, in the setting of incomplete colonoscopy due to strictures, the imaging features of CT will be relied on. This review will focus on the CT features of different colon pathologies leading to strictures and will be illustrated with images from 10 years of experience with CT colonography at our institutions from 2002-2012 (Hotel Dieu Hospital, Queen's University and Mount Sinai Hospital, University of Toronto).

Atonal homolog 1 protein stabilized by tumor necrosis factor α induces high malignant potential in colon cancer cell line

Patients with inflammatory bowel disease (IBD) have an increased risk of developing colitis-associated colorectal cancer (CAC). CAC cells often develop chemoresistance, resulting in a poorer prognosis than that of sporadic colorectal cancer (CRC). The mechanism by which CAC enhances malignant potential remains unknown. We have previously reported that the proteasomal degradation of the transcription factor Atonal homolog 1 (Atoh1) protein results in the non-mucinous form of CRC. It also remains unknown whether Atoh1 protein is expressed in CAC. Therefore, in the present study, we investigated whether Atoh1 protein stabilizes in CAC. Consequently, the treatment with TNF-α stabilized Atoh1 protein through the inactivation of GSK-3β via Akt, resulting in the mucinous form of CRC cell lines. Atoh1 protein also enriched cancer stem cells with upregulated Lgr5 expression and cells in G0/G1 cell cycle phase, resulting in both the chemoresistance to 5-fluorouracil and oxaliplatin and the promotion of cell migration. Immunofluorescence of the human mucinous CAC specimens showed the accumulation of NF-κB p65 at nuclei with the expression of Atoh1 in mucinous cancer. In conclusion, the inflammation associated with carcinogenesis may preserve the differentiation system of intestinal epithelial cell (IEC), resulting in the acquisition of both the mucinous phenotype and high malignant potential associated with the enrichment of cancer stem cell.

Ulcerative colitis-associated colorectal cancer

The association between ulcerative colitis (UC) and colorectal cancer (CRC) has been acknowledged. One of the most serious and life threatening consequences of UC is the development of CRC (UC-CRC). UC-CRC patients are younger, more frequently have multiple cancerous lesions, and histologically show mucinous or signet ring cell carcinomas. The risk of CRC begins to increase 8 or 10 years after the diagnosis of UC. Risk factors for CRC with UC patients include young age at diagnosis, longer duration, greater anatomical extent of colonic involvement, the degree of inflammation, family history of CRC, and presence of primary sclerosing cholangitis. CRC on the ground of UC develop from non-dysplastic mucosa to indefinite dysplasia, low-grade dysplasia, high-grade dysplasia and finally to invasive adenocarcinoma. Colonoscopy surveillance programs are recommended to reduce the risk of CRC and mortality in UC. Genetic alterations might play a role in the development of UC-CRC. 5-aminosalicylates might represent a favorable therapeutic option for chemoprevention of CRC.