Conventional cytologic diagnosis of human papillomavirus-induced anal intraepithelial neoplasia: The experience of a referral center in Rio de Janeiro, Brazil.

Abstract

Screening of anal cancer is rarely available or performed in Brazil. This study analyzes the diagnostic performance of conventional cytology (CC) in the prevention of anal cancer in a coloproctology and gynecology outpatient clinics in a public hospital in Rio de Janeiro, Brazil. From 2005 to 2017, 1066 conventional cytological samples were collected. We analyze the causes of unsatisfactory samples (11.3%) and compare the cytological diagnoses of 83 samples from persons living with HIV and persons not living with HIV and in specific situations, using as the gold standard high-resolution anoscopy or histopathology in cases biopsied within 6 months after cytology. The sensitivity of cytology with diagnosis of ASC-US for detection of anal intraepithelial neoplasia of any grade was 85%, specificity was 41%, positive and negative predictive values were 64% and 75%, respectively, and positive and negative likelihood ratios were 1.46 and 0.35, respectively. Conventional cytology available in resource-limited settings is a simple, noninvasive, low-cost method that proved feasible for outpatient screening of precursor lesions of the anal canal.