Annual anal sampling using DNA screening to identify men who have sex with men at increased risk for anal cancer

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Project Summary/Abstract Since anal cancer incidence is increasing, a uniform standard for anal cancer screening procedures is under investigation with men having sex with men (MSM). But since public health screening is, by nature, a repeated activity, it is not known what proportion of MSM might comply with a repeated screening regimen. Also, as with cervical cancer, anal cancer screening is likely to include HPV DNA testing and visualization of tissue at increased risk for precancerous lesions. This affords the opportunity to investigate home-based screening since it is easier to collect DNA specimens in the home as compared to anal Pap specimens. It also affords the opportunity to assess the proportion of men who will agree to clinic-based visualization of the anal canal using high-resolution anoscopy. Thus, an experiment of repeated DNA screening can efficiently test the following questions: Will MSM comply with annual DNA screening? Will home-based sampling increase compliance? What other factors are associated with repeated annual screening? And, what proportion of men will agree to high-resolution anoscopy? Our long-term goal is to reduce morbidity and mortality from anal cancer given increasing incidence of disease. Our primary objective is to determine compliance with annual DNA-based screening among Houston HIV-positive and HIV-negative MSM, aged ≥27 years, after randomizing the men to home-based DNA collection (arm 1) or clinic-based collection (arm 2). Men randomized to arm 1 will receive an HPV DNA home-based collection kit in the mail at 0 and 12 months and those in arm 2 will be invited to attend an appointment at a clinic where a clinician will collect the DNA specimen at 0 and 12 months. Then, men complying at both time points will be invited in a second consenting process to receive high-resolution anoscopy-directed biopsy to determine the proportion of men who will do this invasive procedure. We will recruit a total of 400 men, with oversampling of African American and Latino men. We hypothesize that a majority of men will comply with annual screening with increased compliance among men in the home-based arm vs clinic-based arm. We will test our hypothesis with 3 specific aims: 1. Determine men's compliance with annual anal HPV DNA specimen collection; 2. Determine factors associated with annual screening compliance. 3. Of those men who comply, establish the proportion in each arm who agree to have HRA. The current research will deliver: 1) The first estimates of compliance with an annual DNA screening program among MSM; 2) The first estimates of the relative ability of HPV DNA home-based screening to increase annual compliance; and 3) Evidence of the influence that home-based vs clinic-based screening has on uptake of HRA. We believe the proposed research could indicate that inexpensive and simple annual PCR testing may identify at-risk MSM who then agree to follow up with HRA; thus, we will determine how high-risk men are identified in light of limited screening resources - crucial knowledge regardless of what anal cancer screening protocol is ultimately recommended.