A 40-year analysis of a colonoscopic surveillance program for neoplasia in ulcerative colitis suggested surveillance colonoscopy may play an important role in reducing colorectal cancer risk and need for colectomy.
Researchers aimed to report updated data from the St. Mark’s Hospital UC surveillance program (started in 1971) to explicate several uncertainties that remain since earlier studies of colorectal cancer (CRC) screening in UC patients. These questions included:
- the magnitude of CRC risk and how it has changed over time;
- interval CRC risk;
- prevalence of multifocal lesions in UC patients; and
- risk of progression to CRC from sporadic adenoma, indefinite for dysplasia, low-grade dysplasia and high-grade dysplasia.
The researchers collected data from medical records, endoscopy and histology reports on 1,375 UC patients (55.3% male) who were followed for 15,234 patient-years (median, 11 years per patient [IQR = 7-17 years]). In total, 8,650 colonoscopies were performed (median, 5 per patient [IQR = 3-8]), 1,098 of which were chromoendoscopy, which was gradually implemented from 2003 onward. Primary end points were defined as death, colectomy, withdrawal from surveillance, or the censor date of January 1, 2013.
They identified CRC in 72 patients (5.2%; IR = 4.7 per 1,000 patient-years). Colectomy for dysplasia decreased over the study period (linear regression, R = – 0.43; P = .007) and advanced CRC and interval CRC have steadily decreased (Pearson’s correlation, – 0.99; both trends P = .01). Early CRC increased 2.5-fold in the current decade (2003-2012) compared with the past decade (1993-2002; P = .045), but 10-year survival was 79.6%. Dysplasia increased 1.5-fold in the current decade compared with the past decade (P = .01), possibly due to the recent increases in the proportion of chromoendoscopies per year over the past 10 years (linear regression, R = 0.98; P < .001), which has twice the effectiveness in detecting dysplasia compared with white-light endoscopy (P < .001). CRC was accompanied by synchronous CRC or spatially distinct dysplasia in 37.5% of cases. CRC risk was comparable between indefinite for dysplasia and low-grade dysplasia.
“The advent of chromoendoscopy in recent years has increased the rate of dysplasia detection. This has not led to the reduction in overall CRC risk, but has allowed the early identification of high-risk patients and played an important role in reducing the risk of advanced and interval cancer,” the researchers wrote. “The colectomy rate for dysplasia has significantly reduced over the past four decades with continued reduction in advanced cancer risk, but perhaps at the cost of a rise in early cancer incidence. However, given the good postsurgical outcome of early cancers, patients may be able to retain their colon despite a dysplasia diagnosis, although they should be fully informed of the risk and benefits associated with undergoing endoscopic or surgical management of dysplasia. Finally, patients with any grade of dysplasia should be regarded as a significant risk, and given the frequency of multifocal neoplasia, these patients require careful inspection of the entire colon with advanced techniques to ensure lesions are not missed.” – by Adam Leitenberger
Disclosure: The researchers report no relevant financial disclosures.