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cancer (16, 18, 31, 33, and 35); this association increases with progressive immunosuppression (CID 1995;21[suppl 1]:S121; NEJM 1997; 337:1343; JID 2001;184:682).
METHOD : The cervix is scraped circumflexually using an Ayer spatula or a curved brush; a sample from the posterior fornix or the "vaginal pool" may also be included. The endocervical sample is taken with a salinemoistened cotton-tipped applicator or straight ectocervical brush that is rolled on a slide and immediately fixed in ethyl ether plus 95% ethyl alcohol or 95% ethyl alcohol alone. The yield is 7-fold higher with thebrush specimen. The following are important steps in obtaining an adequate sample:
- Collect Pap prior to bimanual exam.
- Avoid contaminating sample with lubricant.
- Obtain Pap before samples for STD testing.
- Carefully remove large amounts of vaginal discharge (if present) with large swab before obtaining Pap smear.
- Obtain ectocervical sample before endocervical sample.
- Defer Pap smear if patient is bleeding heavily (small amounts of blood will not interfere with cytologic sampling).
- Apply collected material to slide uniformly, with no clumping. Fix rapidly to avoid air drying. If spray fix atives are used, the spray should be held at least 10 inches away from the slide to prevent disruption of cells by propellant.
When performing speculum examination, if an ulcerative or exophytic lesion sus picious for invasive cancer is noted, the patient should be referred for possible biopsy.
Newer methods of cytologic evaluation using liquid-based collection and thin-layer processing increase sensitivity, decrease frequency of inadequate smears, permit HPV testing, and provide better resolution of ASCUS.
Analysis for HPV-DNA: Screening of Pap smears for high-risk HPV DNA types (including 16, 18, 31, 33, and 35) was compared with standard thin layer Paps for detecting intraepithelial neoplasia (CIN grade 3) or cancer (JAMA 2002;288:1749). Testing for these high-risk HPV types showed higher sensitivity (91% vs 61%) but less specificity (73% vs 82%).
ANAL PAP SMEAR FOR SIL AND CARCINOMA IN MSM : Anal cancer is similar to cervical cancer in many ways: both are caused by infection with one of several oncogenic HPV subtypes, low grade lesions often progress to high-grade lesions, and Pap smear may be an effective screening method (Am J Med 2000;108:674). The prevalence of HPV in MSM is 60% to 75% (JID 1998;177:361) and the frequency of anal carcinoma in men with HIV infection is 35/100,000 or about 80 times that of the general population ((CID 2006;43:223; JAMA
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