Current and Emerging Cervical Cancer Screening Guidelines and Tools

Cervical Cancer Screening Tests
Currently employed screening tests for cervical cancer include the Papanicolaou (Pap) test and the HPV test. The Pap test, a microscopic examination of cells scraped from the cervix (endocervical canal and ectocervix), is the customary approach used to screen for cervical cancer. Although it has a false negative rate of 20% (primarily resulting from sampling error), data indicates that use of this test reduces the incidence of malignancy by 60% to 90%. Once a sample has been obtained, it should be placed on a slide (e.g., conventional Pap test) or in a preservative solution (e.g., Thin Prep Pap test) and sent for analysis. However, upon physical inspection, if suspicious or abnormal specimens are found. a biopsy should be done regardless of cytologic findings.⁹

Approved by the US Food and Drug Administration in 2003, the Hybrid Capture II assay for HPV is another method used to screen women for cervical cancer.  This test, which screens for the presence of high-risk HPV DNA, is indicated for women 30 years of age and older, and is to be used in combination with the Pap test. The HPV test may also be used to interpret ambiguous Pap test findings; additional workup is indicated for women with a Pap test result showing atypical squamous cells of undetermined significance (ASC-US), in conjunction with a positive HPV test.⁹

Current Screening Guidelines
The American Cancer Society (ACS) and US Preventive Services Task Force (USPSTF) currently recommend that all women commence screening either three years after beginning to engage in vaginal intercourse or at 21 years of age, whichever is earlier⁹; guidelines recommend yearly screening with conventional Pap tests or biannual screening with liquid-based Pap tests.¹⁰ In the absence of high-risk factors (e.g., diethylstilbestrol (DES) exposure, HIV infection, other immunodeficiencies), women 30 years of age and older who have had three consecutive normal Pap test results may extend this screening interval to every two to three years.

An alternate option for women 30 years of age and older is to undergo screening every three years with a Pap test and an HPV DNA test. In addition, according to ACS guidelines, women 70 years of age and older with three or more normal consecutive Pap test results and no abnormal results within the last 10 years may discontinue screening. The USPSTF recommends against routine screening for women older than 65 years of age, who have had recent normal Pap tests and are not otherwise at high risk for developing cancer.  Finally, those who have had a total hysterectomy may discontinue cervical cancer screening, unless they have a history of cervical carcinoma or pre-invasive changes.⁹

The American Society for Colposcopy and Cervical Pathology (ASCCP) has developed guidelines for the management of abnormal cervical cytology and histology, as detected by Pap and HPV screening tests. These recommendations are delineated in Table 2.^11,12

Table 2.  Recommendations for the Management of Cervical Abnormalities^11,12

AGC = atypical glandular cells; AIS = adenocarcinoma in situ; ASC-H = atypical squamous cells, cannot rule out high-grade squamous intraepithelial lesions; ASC-US = atypical squamous cells of undetermined significance; CIN = cervical intraepithelial neoplasia; HPV = human papillomavirus; HSIL = high-grade squamous intraepithelial lesions; LSIL = low-grade squamous intraepithelial lesions; Pap = Papanicolaou