Introduction

According to Western guidelines, endoscopic resection (ER) is acceptable for neoplastic lesions with clear boundaries, even within areas affected by ulcerative colitis (UC), and this has increased the opportunities for endoscopic resection However, this procedure is also difficult due to advanced fibrosis of mucosa associated with previous inflammation within areas affected by UC. Underwater endoscopic mucosal resection (UEMR)has become popular in recent years and has been useful for lesions with advanced fibrosis, such as lesions on scars after endoscopic resection. However, there are no reports on lesions on fibrotic mucosa caused by previous inflammation within areas affected by UC.

Aims & Methods

In this study, we verified the safety and usefulness of UEMR for lesions diagnosed as sporadic neoplasms (SN) before ER, among neoplastic lesions that developed within areas affected by UC. We enrolled 35 lesions in 26 patients that underwent UEMR for neoplastic lesions 20 mm or smaller in diameter, which had developed within areas affected by UC, from December 2021 to February 2023 at Keio University Hospital. The primary endpoint was R0 resection rate, while the secondary endpoints were en bloc resection rate, procedure time. and adverse events. Before ER, chromoendoscopy with indigo carmine-dye spraying was performed to confirm the absence of flat type dysplasia around the lesion, then the patients diagnosed with SN were recruited into the study. UEMR was performed on all cases with background mucosa in remission (Mayo Endoscopic Subscore 0 or 1).

Results

The disease types of the subjects consisted of pancolitis in 22 patients (84.6%) and left-sided colitis type in four patients (15.4%), the mean tumor diameter of resected lesions was 11.1 mm, and background mucosa consisted of normal mucosa (regenerated mucosa after inflammation) in nine lesions (25.7%), atrophic mucosa in 20 lesions (57.1%), and atrophic mucosa with ulcer scars in six lesions (17.2%). A total of 34 lesions (97.1%) underwent en bloc resection; of them, 29 lesions (85.3%) underwent R0 resection, while only one (2.9%) underwent piecemeal resection. Median procedure time was 8 minutes. The final pathological diagnosis was SN for all cases: two cases (5.7%) of tubular adenocarcinoma, 21 cases (60%) of tubular adenoma, and 12 cases of sessile serrated lesions (34.3%). In terms of procedural accidents, there were no cases of intraoperative perforation, delayed perforation, post polypectomy coagulation syndrome, and delayed bleeding. Endoscopies performed 1 year later revealed no local recurrence in all cases.

Conclusion

UEMR may be safe and effective endoscopic resection method for SN within areas affected by UC.

References

[1] Yamashina T, Uedo N, Akasaka T, Iwatsubo T, Nakatani Y, Akamatsu T, et al. Comparison of Underwater vs Conventional Endoscopic Mucosal Resection of Intermediate-Size Colorectal Polyps. Gastroenterology. 2019;157:451-61.e2.
[2] Takabayashi K, Kato M, Sasaki M, Iwao Y, Ogata H, Kanai T, et al. Underwater endoscopic mucosal resection for a sporadic adenoma located at severe longitudinal ulcer scars in ulcerative colitis. Endoscopy. 2022;54:E30-e1.

Introduction

Clinical remission and mucosal healing have been advocated as treatment goals for patients with ulcerative colitis (UC). Novel molecularly targeted drugs for the treatment of UC have enabled to target not only clinical remission but also endoscopic remission and even histologic remission.
Recently, the usefulness of novel image enhanced endoscopy (IEE) such as texture and color enhancement imaging (TXI) and red dichromatic imaging (RDI) have been reported in endoscopic evaluation of UC. We aimed to verify the usefulness of the novel IEE in prediction of maintenance of clinical remission in UC patients.

Aims & Methods

Patients with UC in clinical remission who underwent colonoscopy with IEE from March 2021 to December 2023 at our hospital were enrolled in this prospective study.
Disease activities in six segments (cecum, ascending colon, transverse colon, descending colon, sigmoid colon, and rectum) were assessed using white-light imaging (WLI), TXI and RDI. Endoscopic evaluation of disease activity using WLI was performed using Mayo endoscopic score (MES) and the Ulcerative Colitis Endoscopic Index of Severity (UCEIS). IEE evaluation was performed using predefined TXI score (0-2: 2 indicates maximum severity) and RDI score (1-4: 4 indicates maximum severity) for UC. MES of ≤1 and UCEIS of ≤1 were defined as endoscopic remission. With IEE, TXI score 0-1 and RDI score 1 were defined as endoscopic remission in accordance with previous reports. We evaluated the correlation of those scores by Spearman’s rank correlation coefficient. Moreover, relationships between endoscopic remission of WLI, TXI and RDI, and maintenance of clinical remission were evaluated by Kaplan-Meier analysis. Relapse was defined as worsening of clinical symptoms that required additional medical therapies for UC.

Results

Total 117 patients with UC were enrolled. Of these, 17 were excluded because adequate images could not be obtained. Therefore, total 100 patients were assessed. The median MES, UCEIS, TXI, and RDI scores were 1 (range 0-3), 1 (range 0-5), 2 (range 1-3) and 2 (range 1-4), respectively. The average follow-up period was 10.1 months, and 8 cases showed clinical relapse during the observation period.
Evaluation of endoscopic images at each colonic site revealed that UCEIS (P<0.001), TXI score (P<0.001), and RDI score (P<0.001) were significantly associated with MES, respectively. In addition, scores at the most inflamed area showed a positive correlation between MES and UCEIS (r=0.91, P<0.001), MES and TXI (r=0.73, P<0.001), and MES and RDI (r=0.77, P<0.001).
In Kaplan-Meier analysis, MES remission (log-rank, P=0.245), UCEIS remission (log-rank, P=0.701), and RDI remission (log-rank, P=0.827) were not significantly associated with subsequent maintenance of clinical remission. On the other hand, TXI remission (log-rank, P=0.045) was significantly associated with subsequent maintenance of clinical remission.

Conclusion

TXI score and RDI score were significantly associated with existing endoscopic score. In particular, TXI remission was significantly associated with subsequent maintenance of clinical remission. Novel IEE may be useful option in prediction of maintenance of remission in UC patients.