Crohn’s disease was significantly associated with anal canal high-risk human papillomavirus (HPV) infection in a prospective, single-center study of patients undergoing colonoscopy for various indications.
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High-risk HPV and HPV strain 16 were detected in 30% of patients with Crohn’s disease and 18% of patients without Crohn’s disease (P = .005), said Lucine Vuitton, MD, of University Hospital of Besançon (France) and her associates. “Increasing our knowledge of HPV infection of anal tissues could help physicians identify populations at risk and promote prophylaxis with vaccination and adequate screening,” the investigators wrote in the November issue of Clinical Gastroenterology and Hepatology.
Most anal cancers are squamous cell carcinomas, for which infection with high-risk HPV (especially high-risk HPV16) is a driving risk factor. Case studies and literature reviews have linked Crohn’s disease to increased rates of anal canal cancers, but population-based data were lacking, the researchers wrote. Therefore, they prospectively analyzed anal tissue samples from 467 consecutive patients undergoing colonoscopy at a tertiary care center in France. Median age was 54 years (interquartile range, 18-86 years), and 52% of patients were women. No patient had detectable macroscopic neoplastic lesions at the anal margin at baseline.
The researchers used the QIAamp DNA Blood minikit (Qiagen) for DNA extraction and the INNO-LiPA HPV Genotyping Extra kit (Fujirebio Diagnostics) for HPV DNA detection and genotyping. These methods identified HPV DNA in anal tissue samples from 34% of the patients and high-risk HPV DNA in 18% of patients. The most prevalent genotype was HPV16 (detected in 7% of samples), followed by HPV51, HPV52, and HPV39.
A total of 112 patients were receiving at least one immunosuppressive treatment for inflammatory bowel disease or another condition. Seventy patients had Crohn’s disease, and 29 patients had ulcerative colitis. The prevalence of anal canal high-risk HPV and HPV16 infection in patients with ulcerative colitis was similar to that seen in those without inflammatory bowel disease. However, patients with Crohn’s disease were more likely to have anal canal high-risk HPV infection (30%) and HPV16 infection (14%), compared with patients without Crohn’s disease (18% and 7%, respectively). Additionally, among 22 patients with Crohn’s disease and perianal involvement, 11 had HPV DNA in the anal canal versus 30% of other patients with inflammatory bowel disease.
Women were more likely to have anal canal high-risk HPV (23%) infection than were men (13%; P = .004). In a multivariable analysis of self-reported data and medical data, significant risk factors for high-risk HPV infection included female sex, a history of sexually transmitted infections, having more than 10 sexual partners over the life course, having at least one sexual partner during the past year, current smoking, and immunosuppressive therapy. The multivariable analysis also linked Crohn’s disease with anal canal high-risk HPV16 infection (odds ratio, 3.8), but the association did not reach statistical significance (95% confidence interval, 0.9-16.9).
Most patients with Crohn’s disease were on immunosuppressive therapy, “which markedly affected statistical power,” the researchers commented. Nonetheless, their findings support HPV vaccination for patients with Crohn’s disease, as well as efforts to target high-risk patients who could benefit from anal cancer screening, they said.
The work was funded by the APICHU research grant from Besançon (France) University Hospital and by the Région de Franche-Comté. Dr. Vuitton disclosed ties to AbbVie, Ferring, MSD, Hospira, Janssen, and Takeda. Three coinvestigators disclosed relationships with AbbVie, MSD, Hospira, Mayoli, and Roche.
SOURCE: Vuitton L et al. Clin Gastroenterol Hepatol. 2018 Nov. doi: 10.1016/j.cgh.2018.03.008.