Measurement Characteristics of Anal Cytology, Histopathology, and High-Resolution Anoscopic Visual Impression in an Anal Dysplasia Screening Program

Abstract

These data suggest that the reproducibility of key screening measures is moderate at best but of similar magnitude to that of other studies of anal and cervical dysplasia screening. As candidate interventions to treat or prevent precursor lesions enter clinical development, standardization and improvement of measurement methods are essential.

Early Impact and Performance Characteristics of an Established Anal Dysplasia Screening Program: Program Evaluation Considerations

“…The rates of IAC reported in the current study, spanning the first 10 years of potent antiretroviral therapy, are higher than that reported in a cohort of HIV infected patients observed during the period 1996-2003 (92 per 100,000) [23] and comparable to a recent report of IAC incidence among patients with AIDS living in San Diego County between 1996-2000 (144 per 100,000) [19]. There is also evidence that screening procedures thus far recommended [24], based as they are on the model of cervical cancer screening, are relatively simple and safe, with operating characteristics not dissimilar from those reported for cervical cancer screening [5]. Although the addition of HPV typing to cytology is increasingly associated with improved cervical cancer screening program characteristics [25,26], its role in screening for anal cancer precursors, especially among HIV infected patients, is uncertain.…”

“…Other programmatic concerns regarding rescreening relate to the follow up of patients already known to have abnormal cytology. In the same clinic population, we showed that the prevalence of AIN 3 at HRA-directed biopsy was 21% and 27% for ASCUS and LSIL cytology results [5]. Evidence-based guidance regarding optimal frequency of interval examination for those with abnormal cytology is lacking.…”

“…The clinic guideline is annual cytology screening for all patients and this target was approximately achieved for all cytology result categories except for ASCUS (median interval 1305 days). Previous research from the study clinic estimated that the prevalence of AIN 3 at biopsy among those with ASCUS cytology was 21% [5], both justifying referral for HRA and indicating the advisability of regular follow up of such patients. The optimal frequency for repeat screening to reduce important IAC-related endpoints has not been determined and likely depends on factors similar to those reported for cervical cancer: the duration of pre-clinical disease, the progression and regression rates of precursor lesions, the sensitivity of and costs associated with screening tests, and the stage-specific curability of detected disease [61,62].…”

“…In 2001, we implemented a comprehensive screening program for anal cancer and its precursor lesions in the UCSD Owen Clinic, an academic multidisciplinary adult HIV clinic in San Diego and have previously presented our observations regarding the prevalence of detected *Address correspondence to this author at the University of California, San Diego, 200 West Arbor Drive. San Diego, CA 92103-8681, USA; Tel: (619) 543-3939; Fax: (619) 543-7841; E-mail: cmathews@ucsd.edu abnormalities, their association with degree of immunosuppression, and the reproducibility of screening component measurements [5][6][7]. In the current work, we present preliminary findings regarding implementation of our screening program and discuss challenges to scientific evaluation of such a screening program using observational cohort data.…”

Diagnostic methods for prevention of anal cancer and characteristics of anal lesions caused by HPV in men with HIV/AIDS

“…Among the remaining 83 anuscopic findings suggestive of a lesion ≥ HSIL, 62 corresponded to a lesion ≥ AIN 2 at biopsy [37].…”