Increased risk of high-grade dysplasia and colorectal cancer in inflammatory bowel disease patients with recurrent low-grade dysplasia

Dysplasia detection rates under a surveillance program in a tertiary referral center for inflammatory bowel diseases: Real-world data

BACKGROUND AND AIMS

Surveillance colonoscopies are crucial for high-risk patients with inflammatory bowel diseases (IBD) to detect colorectal carcinoma (CRC). However, there is no established quality metric for dysplasia detection rate (DDR) in IBD surveillance. This study assessed the DDR in a dedicated surveillance program at a tertiary referral center for IBD.

METHODS

Consecutive patients with quiescent colitis were enrolled in a cross-sectional study evaluating DDR. High-definition colonoscopy with dye chromoendoscopy (DCE) was performed by a specialized operator. Advanced dysplasia (AD) was defined as low-grade dysplasia ≥ 10 mm, high-grade dysplasia, or colorectal cancer. Risk factors for dysplasia detection were analyzed.

RESULTS

In total, 119 patients underwent 151 procedures, identifying 206 lesions, of which 40 dysplastic with seven AD . Per-lesion and per-procedure DDR were 19.4 % and 20.5 %, respectively. The per-procedure AD detection rate (ADDR) was 4.6 %. A Kudo pit pattern of II-V had a sensitivity of 92.5 % for dysplasia detection but a false positive rate of 64.8 % (p < 0.001). Age at diagnosis and at index colonoscopy and past or indefinite dysplasia were associated with per-procedure dysplasia detection.

CONCLUSIONS

In a real-world setting, a dedicated surveillance program achieved a high DDR. We suggest that optimal DDR in high-risk IBD patients be defined and implemented as a standardized quality measure for surveillance programs.

Image-Enhanced Endoscopy Surveillance of Colon and Pouch Dysplasia in IBD

BACKGROUND

Patients with longstanding ulcerative colitis and Crohn's colitis are at risk for developing colorectal cancer and need regular endoscopic surveillance to detect and remove precursor lesions. To do so, different technologies are available.

DATA SOURCES

The sources are observational and controlled studies, meta-analysis, and expert consensus articles available on PubMed.

STUDY SELECTION

The selected materials include articles reporting outcomes of and recommendations on endoscopic surveillance and resection of dysplasia in the gastrointestinal tract, including the ileoanal pouch and the anal transition zone, in patients with inflammatory bowel disease.

MAIN OUTCOME MEASURES

Incidence and detection rate of dysplasia and cancer with different endoscopic techniques in patients with inflammatory bowel disease.

RESULTS

Risk of cancer is proportional to the duration and extent of the disease, and surveillance interval should be tailored on the individual risk in a range of 1 to 5 years. High-definition imaging and virtual chromoendoscopy have improved the detection of dysplasia and are now comparable with conventional dye spray chromoendoscopy. After restorative proctocolectomy with ileoanal pouch, the risk of cancer is modest, but its high mortality warrants endoscopic surveillance. The evidence to guide pouch surveillance is limited, and recently, the first expert consensus provided a framework of recommendations, which include an initial assessment 1 year after surgery and follow-up depending on individual risk factors.

LIMITATIONS

The limitation includes scarcity of data on ileoanal pouch surveillance.

CONCLUSIONS

Virtual chromoendoscopy and high-definition imaging have improved endoscopic surveillance, and more progress is expected with the implementation of artificial intelligence systems.

Inflammatory bowel disease-related colorectal cancer: Past, present and future perspectives

Inflammatory bowel disease-related colorectal cancer (IBD-CRC) is one of the most serious complications of IBD contributing to significant mortality in this cohort of patients. IBD is often associated with diet and lifestyle-related gut microbial dysbiosis, the interaction of genetic and environmental factors, leading to chronic gut inflammation. According to the “common ground hypothesis”, microbial dysbiosis and intestinal barrier impairment are at the core of the chronic inflammatory process associated with IBD-CRC. Among the many underlying factors known to increase the risk of IBD-CRC, perhaps the most important factor is chronic persistent inflammation. The persistent inflammation in the colon results in increased proliferation of cells necessary for repair but this also increases the risk of dysplastic changes due to chromosomal and microsatellite instability. Multiple pathways have been identified, regulated by many positive and negative factors involved in the development of cancer, which in this case follows the ‘inflammation-dysplasia-carcinoma’ sequence. Strategies to lower this risk are extremely important to reduce morbidity and mortality due to IBD-CRC, among which colonoscopic surveillance is the most widely accepted and implemented modality, forming part of many national and international guidelines. However, the effectiveness of surveillance in IBD has been a topic of much debate in recent years for multiple reasons — cost-benefit to health systems, resource requirements, and also because of studies showing conflicting long-term data. Our review provides a comprehensive overview of past, present, and future perspectives of IBD-CRC. We explore and analyse evidence from studies over decades and current best practices followed globally. In the future directions section, we cover emerging novel endoscopic techniques and artificial intelligence that could play an important role in managing the risk of IBD-CRC.

Methylglyoxal Levels in Human Colorectal Precancer and Cancer: Analysis of Tumor and Peritumor Tissue

Colorectal cancer (CRC) is one of the most common cancers worldwide and its incidence is increasing; therefore, an understanding of its oncogenic mechanisms is critical for improving its treatment and management. Methylglyoxal (MGO) has a highly reactive aldehyde group and has been suggested to play a role in oncogenesis. However, no standardized data are currently available on MGO levels in colorectal precancerous and cancerous lesions. We collected 40 matched colorectal tumor and peritumor tissues from patients with low-grade dysplasia (LGD), high-grade dysplasia (HGD), and invasive cancer (IC). MGO levels increased between LGD, HGD, and IC tumor tissues (215.25 ± 39.69, 267.45 ± 100.61, and 587.36 ± 123.19 μg/g protein, respectively; p = 0.014). The MGO levels in peritumor tissue increased and were significantly higher than MGO levels in tumor tissue (197.99 ± 49.40, 738.09 ± 247.87, 933.41 ± 164.83 μg/g protein, respectively; p = 0.002). Tumor tissue MGO levels did not correlate with age, sex, underlying disease, or smoking status. These results suggest that MGO levels fluctuate in progression of CRC and warrants further research into its underlying mechanisms and function in tumor biology.

Predicting Colorectal Cancer Occurrence in IBD

Patients with colonic inflammatory bowel disease (IBD) are at an increased risk of developing colorectal cancer (CRC), and are therefore enrolled into a surveillance programme aimed at detecting dysplasia or early cancer. Current surveillance programmes are guided by clinical, endoscopic or histological predictors of colitis-associated CRC (CA-CRC). We have seen great progress in our understanding of these predictors of disease progression, and advances in endoscopic technique and management, along with improved medical care, has been mirrored by the falling incidence of CA-CRC over the last 50 years. However, more could be done to improve our molecular understanding of CA-CRC progression and enable better risk stratification for patients with IBD. This review summarises the known risk factors associated with CA-CRC and explores the molecular landscape that has the potential to complement and optimise the existing IBD surveillance programme.

Dysplastic Progression to Adenocarcinoma is Equivalent in Ulcerative Colitis and Crohn's Disease

BACKGROUND

We sought to determine the rate of progression from dysplasia to adenocarcinoma in ulcerative colitis [UC] vs Crohn's diseases [CD] and describe the risk factors unique to each.

METHODS

All adult patients [≥18 years] with a known diagnosis of either UC or CD who underwent a surveillance colonoscopy between January 1, 2010 and January 1, 2020 were included.

RESULTS

A total of 23 751 surveillance colonoscopies were performed among 12 289 patients between January 1, 2010 and January 1, 2020; 6909 [56.2%] had a diagnosis of CD and 5380 [43.8%] had a diagnosis of UC. There were a total of 668 patients [5.4%] with low-grade dysplasia [LGD], 76 patients [0.62%] with high-grade dysplasia [HGD], and 68 patients [0.55%] with adenocarcinoma in the series; the majority of the dysplastic events were located in the right colon. Significantly more UC patients had a dysplastic event, but the rate of LGD and HGD dysplasia progression to adenocarcinoma was not significantly different in CD or UC [p = 0.682 and p = 1.0, respectively]. There was no significant difference in the rate of progression from LGD/HGD to adenocarcinoma based on random biopsies vs targeted biopsies of visible lesions [p = 0.37]. However, the rate of progression from LGD vs HGD to adenocarcinoma was significantly greater for HGD [p < 0.001].

CONCLUSION

While more UC patients were found to have neoplasia on colonoscopy, the rate of progression from LGD and HGD to adenocarcinoma was equivalent in UC and CD, suggesting that endoscopic surveillance strategies can remain consistent for all IBD patients.

Diagnostic interobserver variability in Crohn's disease- and ulcerative colitis-associated dysplasia: a multicenter digital survey from the IG-IBD Pathologists Group

BACKGROUND

Crohn's disease (CD) and ulcerative colitis, two forms of inflammatory bowel disease (IBD), are chronic and relapsing conditions of the gastrointestinal tract both characterized by long lasting chronic inflammation and increased risk of dysplasia and colorectal cancer (CRC). The aim of our study was to evaluate the interobserver agreement about IBD-associated dysplasia among pathologists belonging to the Italian Group for Inflammatory Bowel Diseases (IG-IBD P).

METHODS

The present multicenter survey was performed using telepathology, supported by an open source E-learning platform. Biopsy specimens from 30 colonoscopies and from 20 patients were included. The glass slides of any case, including clinical and endoscopic data, were digitalized and uploaded on the E-learning platform. All the digital slides were grouped in 54 diagnostic "blocks". Blinded histopathological evaluation on all the digital slides was performed by 20 gastrointestinal pathologists. Closed-ended questions about (1) the occurrence of IBD; (2) the classification of IBD (as UC or CD); (3) the presence of active versus quiescent disease; (4) the presence of dysplasia; (5) the possible association of dysplasia with the sites of disease (dysplasia-associated lesion or mass-DALM vs adenoma-like mass-ALM); (6) the grading of dysplasia according to the ECCO guidelines (negative, indefinite, low grade, high grade categories) and (7) the presence of associated serrated features, were proposed in each case. Inter-observer agreement was evaluated by mean agreement percentage and kappa statistic, when suitable.

RESULTS

The diagnosis of IBD was confirmed in 19 of 20 patients, 17 of 19 being classified as UC, 2 as CD. The mean interobserver agreement percentages about (1) the evidence of IBD, (2) the presence of either UC or CD and (3) the activity grading resulted to be 80%, 69% and 86%, respectively. Dysplasia was detected in 8/20 patients, with moderate agreement between pathologists (mean 72%, k 0.48). Particularly, low grade dysplasia was found in 13 biopsies (combined k 0.38), whereas high grade dysplasia in 8 (combined k 0.47). When the endoscopic and histopathological data were combined, features consistent with DALM were found in 6 of 20 patients with low grade dysplasia and those consistent with ALM in 2 patients with low grade dysplasia in a single biopsy (mean agreement: 86%). An associated serrated pattern was discovered in 4 patients (7 biopsies).

CONCLUSIONS

Our study showed moderate interobserver agreement about the histopathological detection and classification of IBD-associated dysplasia. Further efforts should be undertaken to integrate the histopathological data with both the ancillary tests and molecular investigations.