Introduction The natural history of low- grade dysplasia (LGD) found during colonoscopic surveillance of ulcerative colitis is not clear. The optimum strategy, either continued surveillance or immediate colectomy, is debated. The rate of progression of LGD to more advanced neoplasia has been reported to be as low as 0% after 10 years and as high as 53% after a mean follow-up of 5 years.^1,2

Methods All cases of LGD detected at colonoscopy in patients with ulcerative colitis performed between May 1995 and May 2010 were identified, retrospectively, from the pathology database at a single tertiary centre. Endoscopy records and case notes were reviewed and the outcomes for patients undergoing either immediate colectomy or further surveillance endoscopy were included.

Results 22 patients with LGD were identified. 9 patients had endoscopically resectable adenoma – like lesions, and were excluded from further analysis. 13 patients were identified as having unifocal, flat, LGD. The median age was 68 (range 44–87). The median time from diagnosis of ulcerative colitis was 14 years (range 1 to 29 years). All patients were on 5-ASA’s throughout the time period sampled.

8 patients elected to have an immediate colectomy. 5 of 8 resection specimens were negative of LGD, with features of the underlying Ulcerative Colitis. Unifocal LGD was identified in 3 of 8 patients. No advanced neoplasia (HGD or cancer) was identified.

4 patients continued surveillance with a median follow-up of 6.5 years (range 5–9) and a median number of colonoscopies of 5 (range 3–7). LGD was identified on further colonoscopy in 1 patient. This patient then opted for colectomy, but no LGD was identified in the resected specimen. 3 patients had further LGD identified during surveillance endoscopy. The remaining patients had LGD identified at colonoscopies performed outside their scheduled surveillance interval. To date those undergoing surveillance have had no subsequent LGD, HGD or carcinoma.

Conclusion The finding of LGD in patients with ulcerative colitis is associated with a low risk of synchronous or subsequent advanced neoplasia. Continued surveillance may be a reasonable option in this group of patients.

References

1. Befrits R et al. Dis Colon Rectum. 2002;45:615–20

2. Ullman TA et al. Am J Gastroenterol. 2002;97:922–7

Disclosure of Interest None Declared.