Studies support the high incidence

of precancerous lesions in the HIV+ population. Wilkin et al. (2004) analyzed the prevalence of anal precursor lesions in HIV+ men and reported that almost ½ of patients had abnormal cytology on the anal Pap smear and subsequently 40% of these patients were found to have AIN histology by biopsy (14). Kreuter et al (2010) prospectively examined a population of 400 HIV+ MSM over a period of 5 yrs and determined that over 70% had some Inhibitors,research,lifescience,medical degree of AIN (10). 35% had high grade AIN and 2.5% had anal cell cancer detected on screening. More importantly Kreuter et al (2010) demonstrated that untreated AIN can progress to anal cancer in as little as 8 months (10). Previous studies in the mid 1990’s had showed AIN progressing to anal cancer over 3-5 years (14), (15).

Also studies indicate that that the incidence of AIN has increased with the widespread Inhibitors,research,lifescience,medical use of HAART in the HIV+ population (15). The feasibility of screening for anal cancer has been research extensively over the past decade. New York State has Inhibitors,research,lifescience,medical established screening guidelines for anal cancer in HIV+ patients (16). They recommend that all HIV+ patients undergo screening for anal cancer and propose a similar screening scheme to cervical cancer. Initially patients should have an annual visual and digital rectal exam plus an anal PAP. If PAP reveals abnormal anal cytology then a high-resolution anoscopy (HRA) should be performed similar to the colposcopy in cervical cancer. One caveat to anal cancer screening is that while the test is sensitive it is not specific. Both Palefsky et al (1997) and Goldstone et al (2001) showed that over 70%-90% of HIV+

MSM had some abnormal Inhibitors,research,lifescience,medical cytology on anal pap (17), (18). The correlation of abnormal pap with HSIL biopsy was poor. Therefore, Inhibitors,research,lifescience,medical all lesions noted on HRA should be biopsied. If HSIL is detected treatment should be offered, either medical FHPI in vivo ablation or surgical excision. If LSIL is detected the recommendation is to have repeat anal pap smears in 3-6 months. If persistent abnormal pap, these patients should have yearly HRA. Mount Sinai implemented this practice in 2007 for all HIV+ patients (19). Researchers believe such practices are both cost effective and efficacious. Goldie et Thalidomide al (1999) performed a cost analysis on screening for AIN and found that screening increased quality-adjusted life expectancy for all HIV+ patients (20). Goldie et al (1999) calculated that screening with anal pap tests every year around time of diagnosis of HIV resulted in an incremental cost-effectiveness ratio of $16,600 per quality-adjusted life year saved (20). Screening more frequently than yearly did not provide any additional benefit. Once HSIL histology is confirmed, there are a couple of treatment options. However there is still debate on the most efficacious treatment for precursor anal lesions.