21. Risk of anal neoplasia and cancer associated with glucocorticoid use and immune-related conditions

Abstract

Background: Corticosteroid use is associated with increased risk of anal neoplasia in transplant patients. We investigated the relationship between these medications, indications for their use, and risk of anal neoplasia in the general population. Methods: Men (n = 119) and women (n = 187) diagnosed with anal carcinoma in situ or anal cancer (AC) in the Seattle area (1986–2004) were compared with controls (n = 239 men and n = 1445 women), matched for sex and age. In-person interviews included questions about medical history and medications used for >6 months. Odds ratios (OR), and 95% confidence intervals (CI), were used to approximate the relative risk and adjusted for age, smoking, and number of partners. Results: AC was associated with corticosteroid use for women (OR 2.4, 95% CI 1.5–3.9) but not men (OR 1.4, 95% CI 0.5–4.0). We also investigated conditions associated with corticosteroids including diabetes, asthma, sinusitis, chronic kidney disease, and arthritis. Two immune-related conditions were associated with increased risk of AC in women but not men, specifically chronic kidney disease (women: OR 5.8, 95% CI 2.3–14.9; men: OR 1.0) and arthritis (women: OR 2.8, 95% CI 1.4–5.4; men: OR 0.3, 95% CI 0.1–1.7). Conclusions: Our population-based study suggests that women who use corticosteroids or have immune-related conditions may be at increased risk of AC. Future studies that examine dose and duration of corticosteroid use are needed to confirm these findings. As screening guidelines for anal neoplasia develop, consideration of women with a history of indications for immune suppression are warranted.