Anal Dysplasia in Kidney Transplant Recipients

Background: Although the risk of anal cancer in immunosuppressed individuals is significantly higher than in the general population, methods for detecting precancerous anal dysplasia have not been well studied in solid-organ transplant recipients. We sought to identify the incidence of anal dysplasia in kidney transplant recipients and associated factors that increase the likelihood of dysplasia. Study Design: We prospectively analyzed kidney transplant recipients who had been immunosuppressed for at least 6 months with a functioning allograft. We interviewed willing participants and performed anal cytology sampling and high-resolution anoscopy; if we found microscopic abnormalities, we performed biopsies. We used univariate analysis to measure the association between variables and anal dysplasia. Results: Of the 40 participants, 15 were women and 25 were men; their mean age was 61 years. Their median duration of immunosuppression was 5.6 years; 23 (59%) had fewer than 5 lifetime sexual partners, and 2 (5%) reported ever practicing anal intercourse. Of all cytology specimens, 35 (88%) had sufficient cells for interpretation and 2 (6%) demonstrated dysplasia. We performed biopsies in 11 patients; 6 had dysplasia (4 low-grade, 2 high-grade). Of these patients, five had normal anal cytology. The sensitivity of cytology to predict histologic evidence of dysplasia was 17%. Overall, seven (18%) had dysplasia according to either cytology or histology specimens; two (5%) had high-grade dysplasia. We found no significant associations between the tested variables and the presence of dysplasia. Conclusions: A significant proportion of kidney transplant recipients harbor anal dysplasia. One time anal cytology sampling was not predictive of histologic findings. Although these findings confirm their high risk for dysplasia, a larger sample is required to more accurately quantify risk factors for dysplasia and progression to cancer.