State-of-the-Art of High-Resolution Anoscopy as a Tool to Manage Patients at Risk for Anal Cancer

Comparison between anal cytology, high-resolution anoscopy and HPV DNA genotyping by polymerase chain reaction in the post-treatment follow-up of condylomata acuminata

AIM

to evaluate the presence of subclinical HPV-induced anal lesions with anal cytology, High-Resolution Anoscopy (HRA) and HPV genotyping by polymerase chain reaction (PCR) in the follow-up of treated condylomata acuminata (CA).

METHODS

seventy-nine male patients were included. One month after anal CA eradication, the patients underwent brush samples collection for anal cytology and PCR, and HRA with biopsy of acetowhite lesions. These methods were compared within all patients and between groups, according to Human Immunodeficiency Virus (HIV) infection status: HIV-negative; HIV-positive with TCD4 count above and below 350 cells/mm3.

RESULTS

the most frequent HPV types were 6 and 16. HPV DNA was isolated in 92%. HIV infection was associated with a higher number of oncogenic HPV types (p=0.038). All patients with negative PCR had negative HRA and cytology. There were no differences in cytological, HRA or histopathological findings between groups.

CONCLUSION

the association of the findings of cytopathology, HRA and genotyping of HPV refined the diagnosis of HPV-induced lesions. The degree of immunodeficiency was not associated with increase in remnant HPV-induced anal lesions.

Anal cancer screening knowledge, attitudes, and experiences among men who have sex with men in Ottawa, Ontario

Anal cancer is rare; however, men who have sex with men (MSM) are at significantly increased risk compared to the general population. In Canada, no widespread screening programs nor accepted standards of care exist to inform primary care physicians (PCP) regarding screening and prevention for MSM patients. Our objective was to assess the knowledge, attitudes and experience of a sample of MSM regarding anal cancer risk, screening, prevention, and acceptability of HPV vaccination. A cross-sectional survey was conducted at an STI clinic for MSM in Ottawa, Ontario over a 20-week period. Descriptive statistics, Pearson's Chi-square test and binary logistic regression for comparisons between groups were completed. Fifty-five percent of respondents were aware of increased anal cancer risk among MSM; 47.7% were aware that HPV is the primary cause. Only 14.8% of men with a PCP had discussed anal cancer screening and prevention with their PCP. Of those who had not, 86.0% indicated they would be comfortable having that discussion. Just under 8% reported receiving an appropriate screening test. The HPV vaccination rate was 16.2%. The majority of respondents who had not been vaccinated expressed openness to vaccination. A clear deficiency was observed in terms of MSM knowledge regarding anal cancer risk and inclusion of this health concern in their primary care. This highlights the need for more discussion between MSM and their PCPs to ensure MSM are aware of their risk and of available screening and prevention options recognizing the limited evidence-base for anal cancer screening.

[Practical considerations for high resolution anoscopy in patients infected with human immunodeficiency virus]

Anal cancer is uncommon in the general population, however its incidence is increasing significantly in certain risk groups, mainly in men who have sex with men, and particularly those infected with human immunodeficiency virus. High resolution anoscopy technique is currently considered the standard in the diagnosis of anal intraepithelial neoplasia, but at present there is no agreed standard method between health areas. High resolution anoscopy is an affordable technique that can be critical in the screening of anal carcinoma and its precursor lesions, but is not without difficulties. We are currently studying the most effective strategy for managing premalignant anal lesions, and with this article we attempt to encourage other groups interested in reducing the incidence of an increasing neoplasia.

Performance characteristics of anal cytology and human papillomavirus testing in patients with high-resolution anoscopy-guided biopsy of high-grade anal intraepithelial neoplasia

PURPOSE

High-resolution anoscopy is colposcopy of the anus after applying 3 percent acetic acid. High-resolution anoscopy with biopsy was used as the standard for detecting high-grade anal neoplasia and was compared to detection of high-grade anal neoplasia by anal cytology, human papillomavirus testing, or the combination.

METHODS

A total of 125 men who have sex with men (MSM) were enrolled from a group of MSM identified by random digit dialing: HIV-negative = 85, HIV-positive = 35, and unknown status = 5. A specimen was taken for anal cytology and human papillomavirus testing, followed by high-resolution anoscopy with biopsy of any lesions.

RESULTS

Ninety-one percent of HIV-positive and 57 percent of HIV-negative MSM had anal human papillomavirus infection. In HIV-positive men the sensitivity of abnormal cytology to detect high-grade anal neoplasia was 87 percent, and in HIV-negative MSM it was 55 percent. Among HIV-negative men, 9 of 20 cases of high-grade anal neoplasia would have been missed because cytology was negative, but the addition of human papillomavirus positivity increased sensitivity for the combination to 90 percent.

CONCLUSIONS

Sensitivity and specificity of anal cytology and human papillomavirus testing are different in HIV-positive and HIV-negative MSM for detecting high-grade anal neoplasia when patients have high-resolution anoscopy-guided biopsy of lesions. The optimum use of human papillomavirus testing has yet to be defined. High-resolution anoscopy is an effective tool for diagnosing high-grade anal neoplasia.