Emerging Technology Aids in Cervical Cancer Screenings
Vaccination against the human papillomavirus (HPV) strains that increase cervical cancer risk are expected to reduce cervical cancer rates in decades to come. For the time being, screening and early detection remain crucial fronts in cancer control.
Early detection with Pap tests and liquid-based cytology has dramatically reduced mortality rates, and newer HPV DNA testing for high-risk lesions promises to lower those rates even further. The past year has seen the release of new research and screening guidelines for cervical cancer, as well as emerging screening technologies and strategies.
Less than a decade after widespread HPV vaccination began in the United States, and despite relatively low vaccination rates (eg, 23% among women aged 18 to 26)1, a new study suggests public health benefits might already be discernable.2 The study reports significant trends toward declining rates of high-grade cervical lesions and adenocarcinoma in situ among women between the ages of 21 and 39 since the initiation of vaccination efforts.2
The full benefits of HPV vaccination against high-risk HPV subtypes aren't expected to fully materialize for several years; however, a wave of new revisions to cervical cancer screening guidelines since the vaccines' approval represents an important evolution in cervical cancer control efforts.
In the past year and a half alone, the Cochrane Gynaecological Cancer Group has published a new meta-analysis of HPV testing versus repeat cytology, and the United States Preventive Services Task Force (USPSTF), American Congress of Obstetricians and Gynecologists (ACOG), the American Cancer Society (ACS), and other organizations have all revised their screening guidelines.3-8
These new guidelines include a reduced reliance on Pap results and increased reliance on Pap and HPV DNA testing (“co-testing”), among other important changes. The changes might well improve patient participation rates, thanks to reduced recommended number and frequency of screenings, as well as increased patient convenience.9
The Joint Consensus American Cancer Society Guidelines for Cervical Cancer Screening7
• Girls and women younger than 21 years of age should not undergo cervical cancer screening.
• Except for immunocompromised women, no woman, regardless of age, should undergo annual screening, either with Pap tests or HPV DNA tests.
• Cervical cancer screening should begin at age 21, regardless of risk factors, with women age 21 to 29 undergoing cytology (conventional Pap smears or liquid-based cytology) every 3 years.
• HPV DNA testing should not be used among women younger than 30 years of age.
• Women between the ages of 30 and 65 should undergo screening every 5 years with cytology plus HPV testing (“co-testing”), but can also continue cytology-only screening every 3 years if they so choose.
• Women greater than 65 years of age, who have had three consecutive negative cytology tests or two consecutive 5-year cytology plus HPV DNA co-tests, and with the most recent test no more than 5 years before age 65, should stop undergoing screenings.
• No screening is indicated for women who have had the cervix or entire uterus removed and who do not have any history of cervical intraepithelial neoplasia 2 (CIN2) or more severe diagnosis.
• Women with a history of CIN2 or more severe should undergo screening for at least 20 years, even beyond 65 years of age.
• Immunocompromised women (eg, those undergoing cancer chemotherapy, organ transplantation, or who are HIV-positive) should undergo screening twice during the first year after diagnosis, and then annually.
The ACS consensus recommendations, which were released jointly with those of the American Society of Colposcopy and Cervical Pathology and the American Society of Clinical Pathologists, include HPV DNA testing and extend testing intervals for many women.7,9