Perianal Crohn’s Disease and the Development of Colorectal and Anal Cancer: A Systematic Review and Meta-analysis

Abstract

Background and aims The aim of this systematic review was to assess the literature on the incidence and risk factors for colorectal cancer and anal cancer in patients with perianal Crohn’s disease. Method A systematic review of the literature was performed using PubMed, Embase and Google Scholar. A meta-analysis was then conducted using a random-effect model. Results Five studies were included in the systematic review. Out of all patients, 26.5% had perianal Crohn’s Disease. The median follow-up was six years. In total, 127 cases of colorectal cancer were found (0.43% of the included Crohn’s disease patients). Perianal involvement was present in 50% of colorectal cancer patients (0.89% of the population). Three of the studies specified the cancer to be rectal or anal, which were present in 68 and 24 cases (0.3% and 0.1% of patients), respectively. In a subgroup analysis of rectal- and anal cancer, perianal involvement was most frequent in anal cancer, accounting for 46% of the cases. In the rectal cancer group, 37% had perianal involvement. The higher incidence of colorectal cancer in patients with perianal Crohn’s was confirmed in a meta-analysis. Conclusion Half of patients with colorectal cancer and anal cancer were found to have perianal Crohn’s. In patients with perianal involvement, there was a higher percentage of anal cancer compared with rectal cancer. These results support the theory that patients with perianal Crohn’s are at increased risk for developing colorectal- and anal cancer. Studies, collecting more detailed data about patients and their cancers, are necessary to further specify the disease course.

Colorectal Cancer: Epidemiology, Risk Factors, and Prevention

“…Specific comorbidities were suggested as risk factors for developing CRC. Patients with inflammatory bowel disease (IBD), including ulcerative colitis or Crohn disease, are at high risk of CRC [116][117][118][119]. Higher risks of CRC were also reported in patients with other comorbidities, including cystic fibrosis [120,121], renal transplantation [122], cholecystectomy [123], coronary heart disease [124], bacterial and viral infections (e.g., human papilloma virus, Helicobacter pylori) [125][126][127][128], antibiotic use [129,130], and diabetes mellitus and insulin resistance [131][132][133].…”

Nonfistulizing Perianal Crohn's Disease

“…The risk is increased in CD patients with anal or perianal disease and some authors postulate that conjunction of human papillomavirus (HPV) infection and CD-related chronic local inflammation contributes to this increased risk. [49][50][51] The clinical presentation, diagnosis, and management of anal cancer in CD patients does not differ from that of sporadic anal cancer, except when it occurs in a fistula. "Anal cancer" broadly represents (1) cancer of the anal canal, (2) perianal cancer, and (3) fistula-associated cancer.…”

“…The risk is increased in CD patients with anal or perianal disease and some authors postulate that conjunction of human papillomavirus (HPV) infection and CD-related chronic local inflammation contributes to this increased risk. 49 50 51…”

Overcoming cancer risk in inflammatory bowel disease: new insights into preventive strategies and pathogenesis mechanisms including interactions of immune cells, cancer signaling pathways, and gut microbiota

“…A recent meta-analysis revealed a higher incidence of anal cancer in patients with perianal CD compared to the general patient population. Notably, perianal involvement accounted for the majority of cases of anal cancer, representing 46% of the cases ( 12 ). Another meta-analysis highlighted an increased risk of anal cancer in patients diagnosed with both CD and UC.…”