High-Resolution Anoscopy for Anal and Perianal Cancer Precursors in Patients With Long-term Pharmacologically-Induced Immunosuppression

Abstract

Introduction: Immunosuppressed patients have a higher risk of human papillomavirus (HPV) infection and HPV-related cancers, like anal squamous cell carcinoma (SCC). Information regarding precancerous anal lesions (high-grade anal squamous intraepithelial lesions) in the long-term immunosuppressed patients of pharmacological origin is lacking, especially when high resolution anoscopy (HRA), the most reliable examination tool, is employed. Methods: Retrospective analysis of long-term pharmacologically immunosuppressed patients that have been evaluated and followed with HRA. Results: Data search revealed 48 patients under immunosuppression due to pharmacological agents. In this analysis, we excluded those with multiple causes such as HIV positivity (n=1) and men who have sex with men (n=4). Of the remaining 43 patients, 37 were women, mean age was 49 ±18 years. The most common conditions were Inflammatory bowel disease (n=11, 26%), renal transplantation (n=9, 21%) and systemic lupus erythematosus (n=8, 19%). The most commonly used drugs were prednisolone (n=29), azathioprine (n=21) and tacrolimus (n=9), with a mean duration of immunosuppression of 12±11 years. Twenty-one patients (50%) were current or previous smokers. At the first evaluation with HRA, 23 patients (53%) were diagnosed with anal and/or perianal high-grade squamous intraepithelial lesions (HSIL) and in one case perianal SCC was diagnosed. A mean of 4±2 lesions of the anal canal and a mean of 3±2 lesions of perianus were detected. Considering also the previous history and follow-up with HRA, overall 29 patients (67%) in our series had anal and/or perianal HSIL. Sixteen patients (55%) had both anal and perianal HSIL, 10 (35%) had only anal and 3 patients (10%) only perianal high-grade lesions. In total, 3 patients had perianal SCC, one patient with a previous history and two were detected in the HRA clinic. Prednisolone was a risk factor for anal HSIL (OR=4.7, 95%CI=1.209-18.468, P=0.026) and anal HSIL was a risk factor for perianal HSIL (OR=7.5, 95%CI=1.706-32.676, P=0.008). Conclusion: In our cohort of immunosuppressed patients due to pharmacological agents, anal and perianal HSIL/cancer was common. HRA enabled the detection of these lesions which were likely to be missed by other methods of examination.