Anal HPV Infection and Abnormal Cytology in HIV-infected Women
Condition: Cervical Cancer Screening; HIV Infections
MeSH terms: Infections; Communicable Diseases; Papillomavirus Infections
Study type: Observational

Summary: 
      The population of HIV infected women seen at Boston Medical Center may have a higher
      frequency of anal cytologic and histologic abnormalities than what is reported for the
      non-HIV infected population.
    

Detailed description: 
      BACKROUND FOR THIS STUDY Anal cancer is a growing problem in the US. The incidence of anal
      cancer has increased among both men (160%) and women (78%) from 1973 to 2000 in the US [1].
      In HIV-infected men the incidence of SCCA (squamous cell cancer of the anus) was found to
      range from 49-92 per 100,000 patient years [2]. This prompted recommendations on screening
      for anal cancer in this population. HIV-infected women are also at increased risk for
      developing anal cancer. A study based on data from AIDS and cancer registries found that the
      risk of anal cancer among women in the general population is about 1.2% and it increases up
      to 3.9% in the HIV-infected women. In addition, HIV-infected women had eight times the risk
      of in situ anal cancer compared with the number of expected cases [3].

      SCCA appears to have many similarities to cervical cancers. HPV has been detected in 88% of
      anal cancer specimens with HPV-16 found in 73% of SCCA and HPV-18 in 7% [1]. In addition,
      SCCA develops in the transformation zone between the squamous epithelium of the anus and the
      columnar epithelium of the rectum, is frequently associated with dysplasia of the anus and
      may be preceded by squamous intraepithelial changes which are also associated with HPV.

      Cervical cytology, also known as pap smear, can detect cervical cancer and its precursors.
      Countries who have adopted cervical cancer screening programs have had dramatic decreases in
      both the morbidity and mortality rates of cervical cancer.

      Anal cytology may also be used to screen for HPV associated anal lesions, and among
      HIV-infected men who have sex with men, an abnormal cytology is frequently associated with a
      dysplastic squamous cell lesion of the anus. Anal HPV infections (high risk types) have been
      found in 53 ¿ 95% of HIV-infected men. Abnormal anal cytology has been found in 41-81% of
      HIV-infected men screened with high-grade cytologic findings in 2-25% of these patients [2].

      There have been only a few studies looking at anal cytology in HIV-infected women. The
      largest study (n=235), by Holly and Palefsky [4], found that HIV positive women had a 26%
      prevalence of anal cytologic abnormalities (mostly atypical squamous cells of undetermined
      significance [ASCUS] and low grade squamous intraepithelial lesions [LSIL]). Forty-six of
      these women with abnormal cytology (60) underwent high resolution anoscopy (HRA) and 14 were
      found to have biopsy proven HSIL.

      Several risk factors for anal cytologic abnormalities in women have been suggested, such as
      positive anal HPV test, history of anal intercourse, history of cervical squamous
      intraepithelial lesions (SIL), history of vulvar warts, multifocal cervical SIL, history of
      sexually transmitted infections, more than 10 sexual partners, history of cervical, vulvar or
      vaginal cancer, immunosuppression after solid organ transplantation, HIV infection, long-term
      corticosteroids use and cigarette smoking.

      It has been suggested that all HIV-infected women, women with cervical cancer and women with
      high-grade vulvar disease or cancer should be screened for anal cytologic abnormalities.
      However, as described above there is very scanty literature describing the prevalence and
      incidence in this patient population and the largest study was conducted prior to the HAART
      era.

      We plan to estimate the prevalence and 6-12 month incidence of abnormal anal cytology with
      histologic correlates in the HIV-infected women seen at BMC. We hope that the information
      will allow us to make screening recommendations for this patient population.
    

Observational model: Cohort
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        HIV infected women aged between 18-64 years presenting for cervical cytologic screening.
      
Keywords: HIV; women; anal cytology