Anal cancer is caused by human papillomavirus (HPV), which can cause changes to the skin around and mucous epithelium inside the anus. Although in the general population is anal cancer a relatively rare neoplasia with incidence between 1 to 2 cases per 100,000 people, estimates of the anal cancer rates among HIV positive men who have sex with men (MSM) range from 70 to 137 cases per 100,000. Anal cytology and HPV detection are important tools for the anal cancer screening. Aim of this study was to compare patient’s characteristics with the anal cytology results.
In this study HIV positive MSM attending Dermatovenereology Department of Nemocnice Na Bulovce who signed an informed were included. Anorectal cytology and HPV specimens sample were taken from the entire length of the anal canal mucosa using a moistened Dacron swab. After sampling, cells from the swab were washed into a vial with liquid-based cytological medium. In the cytological laboratory, samples were processed to evenly disperse as a thin monolayer of cells while removing background obscuring materials. The presence of anal HPV-DNA was detected by PCR with broad spectrum primers followed by hybridization.
The average age of the 80 HIV positive MSM who agreed to participate in the study was 33.8 years (range 23-57). In our study 65 (81.3%) of the patients were on highly active antiretroviral therapy (HAART) for more than 3 months prior to the specimen collection. Average CD4 cell count of the patients at the time of the study was 671 cells/mm3 (range 361-1180). HPV-DNA was detected among 71 (88.8%) of the patients. HR-HPV infection was present among 47 (58.8%) patients. Low-grade squamous intraepithelial lesion (LSIL) was detected in 34 (42.5%) patients, normal cytology (NILM) had 23 (28.8%) patients and none of the patients had high-grade squamous intraepithelial lesion (HSIL). HR-HPV anal infection was significantly more common among patients under 34 years of age (73.3% vs. 40.0%; p < 0.01). Presence of abnormal cytology was not associated with patient’s age, HAART or CD4 cell count.
Our preliminary results suggest that anal HR-HPV infection is more common among younger HIV positive MSM. We did not observed association between the presence of HR-HPV infection and HAART or CD4+ cell count over 350. Similarly abnormal cytology among HIV positive MSM in our stuy was not associated with these factors. Because the results are based on the preliminary data obtained from a small number of patients and none of the patients had CD4 cell count under 350 cells/mm3 they should be interpreted with caution.