Crohnʼs Disease-Associated Colonic Dyplasia & Cancer: Lessons Learned from 93 Cases

Abstract

Purpose: Endoscopic surveillance is not always employed for patients with colonic Crohn's disease (CD). In addition, management of CD-associated colonic dysplasia or cancer, once detected, is debatable. The aims of the study were to characterize clinical, endoscopic, and histologic features & natural history of CD-associated dysplasia/cancer as a source of information for 1) surveillance recommendations; 2) risk factors for progression from dysplasia to cancer; & 3) surgical treatment. Methods: Database search was performed for patients with CD-associated dysplasia/cancer during the last 30 years. Biopsies and surgical specimens were reviewed by an expert GI pathologist. Demographic, clinical, endoscopic and surgical variables were studied. Results: 93 patients with CD-associated dysplasia/cancer were identified: 32 (34%) had dysplasia, 22 (24%) had dysplasia and cancer and 39 (42%) had cancer without dysplasia. High-grade dysplasia (HGD) was found in 49/93 (53%) [72% of the dysplasia group and 43% of the cancer group] and was multifocal in 27/49 (55%) [57% in dysplasia group, and 54% in cancer group]. Low-grade dysplasia (LGD) was found in 29/93 (31%) [59% in dysplasia group, and 16.4% in cancer group] and was multifocal in 13/29 (45%) [47% in dysplasia group, and 40% in cancer group]. 18/61(30%) of cancer patients had dysplasia found in at least 1 preoperative endoscopy. CD characteristics are shown in Table 1. Patients with dysplasia who were treated with 5-aminosalicilates (5ASA) at any time, were less likely to progress to cancer (OR 2.94, 95% CI 1.22–7.12 P= 0.016) than those without 5ASA treatment. Conclusion: 1) Dysplasia in colonic CD often is multifocal; 2) Concurrent dysplasia was found in a substantial number of CD-associated colon cancers; and 3) 5ASA use may protect from progression of dysplasia to cancer. Our findings support routine endoscopic surveillance for colonic CD as in ulcerative colitis and chemoprevention with 5ASA. Colonic CD with dysplasia may require radical surgery due to the multifocal nature of dysplasia and the risk for future cancer.Table: Risk Factors for Dysplasia Progression to Cancer