Systematic review with meta‐analysis: IBD‐associated colonic dysplasia prognosis in the videoendoscopic era (1990 to present)

Abstract

Background Introduction The prognosis of dysplasia in patients with IBD is largely determined from observational studies from the pre‐videoendoscopic era (pre‐1990s) that does not reflect recent advances in endoscopic imaging and resection. Aims To better understand the risk of synchronous colorectal cancer and metachronous advanced neoplasia (ie high‐grade dysplasia or cancer) associated with dysplasia diagnosed in the videoendoscopic era, and to stratify risk according to a lesion's morphology, endoscopic resection status or whether it was incidentally detected on biopsy of macroscopically normal colonic mucosa (ie invisible). Methods A systematic search of original articles published between 1990 and February 2020 was performed. Eligible studies reported on incidence of advanced neoplasia at follow‐up colectomy or colonoscopy for IBD‐dysplasia patients. Quantitative and qualitative analyses were performed. Results Thirty‐three studies were eligible for qualitative analysis (five for the meta‐analysis). Pooled estimated proportions of incidental synchronous cancers found at colectomy performed for a pre‐operative diagnosis of visible high‐grade dysplasia, invisible high‐grade dysplasia, visible low‐grade dysplasia and invisible low‐grade dysplasia were 13.7% (95% CI 0.0‐54.1), 11.4% (95% CI 4.6‐20.3), 2.7% (95% CI 0.0‐7.1) and 2.4% (95% CI 0.0‐8.5) respectively. The lowest incidences of metachronous advanced neoplasia, for dysplasia not managed with immediate colectomy but followed up with surveillance, tended to be reported by the studies where high definition imaging and/or chromoendoscopy was used and endoscopic resection of visible dysplasia was histologically confirmed. Conclusions The prognosis of IBD‐dysplasia diagnosed in the videoendoscopic era appears to have been improved but the quality of evidence remains low. Larger, prospective studies are needed to guide management. PROSPERO registration no: CRD42019105736.

Multi-centre derivation and validation of a colitis-associated colorectal cancer risk prediction web-tool

“…The development of advanced endoscopic resection techniques of non-polypoid dysplasia such as endoscopic submucosal dissection (ESD) and hybrid ESD/endoscopic mucosal resection (EMR), have allowed a greater number of these lesions to be endoscopically resected, when previously they would have been consigned to colectomy surgery 10 . More recent case series and smaller cohort studies from centres where high definition chromoendoscopy surveillance and advanced endoscopic resection techniques have been used have demonstrated lower rates of truly invisible dysplasia detection and lower AN progression rates after dysplasia has been endoscopically resected 8–10 . The univariate analyses in our study have indicated that whether or not a visible LGD lesion can be completely endoscopically resected is a more prominent risk factor than its morphology.…”

“…Due to a high CRC risk, high-grade dysplasia (HGD) warrants preventive colectomy surgery or e n bloc endoscopic resection with intensive surveillance follow-up if unifocal 4–7 . The natural history of low-grade dysplasia (LGD) progression is less well defined with a wide range of rates reported for progression of LGD lesions to advanced neoplasia (HGD or CRC) due to the inclusion of historical data from small population studies with heterogenous terminology and limited follow-up 8 . The quality of endoscopic surveillance has also evolved over the past three decades with standardisation of surveillance technique, advances in imaging technology such as high definition white-light imaging and chromoendoscopy, and resection techniques such as endoscopic mucosal resection and submucosal dissection.…”

“…The quality of endoscopic surveillance has also evolved over the past three decades with standardisation of surveillance technique, advances in imaging technology such as high definition white-light imaging and chromoendoscopy, and resection techniques such as endoscopic mucosal resection and submucosal dissection. These advances have been linked with higher rates of visible dysplasia detection, lower proportions of dysplasia categorised as “invisible” and lower AN progression rates 8–10 . A recent systematic review of studies from the videoendoscopic era has found wide variation in AN progression rates after endoscopic resection from 0 – 23% at 5 years for polypoid LGD and 0 – 22% at 2 years for non-polypoid LGD 8 .…”

“…These advances have been linked with higher rates of visible dysplasia detection, lower proportions of dysplasia categorised as “invisible” and lower AN progression rates 8–10 . A recent systematic review of studies from the videoendoscopic era has found wide variation in AN progression rates after endoscopic resection from 0 – 23% at 5 years for polypoid LGD and 0 – 22% at 2 years for non-polypoid LGD 8 . A large observational study evaluating the effect of endoscopic resection on long-term LGD prognosis is required to be able to better inform patients of their cancer risk if they continue surveillance rather than have a colectomy.…”

Multicentre derivation and validation of a colitis-associated colorectal cancer risk prediction web tool

“…[4][5][6][7] The natural history of low-grade dysplasia (LGD) progression is less well defined with a wide range of rates reported for progression of LGD lesions to advanced neoplasia (AN; HGD or CRC) due to the inclusion of historical data from small population studies with heterogeneous terminology and limited follow-up. 8 The quality of endoscopic surveillance has also evolved over the past three decades with standardisation of surveillance technique, advances in imaging technology such as high-definition white-light imaging…”