Are we ready for primary HPV testing for the prevention of cervical cancer?

Primary cervical cancer screening with cytology

Primary screening with cervical cytology alone remains an option supported by many authorities and professional society guidelines.¹¹ Most studies report that HPV testing has greater sensitivity than cervical cytology alone, especially for the detection of adenocarcinoma of the cervix.¹² In one Canadian study, 10,154 women were randomly assigned to HPV or cervical cytology testing. The sensitivity of HPV testing and cervical cytology for detecting cervical intraepithelial neoplasia grade 2 or 3 was 95% and 55%, respectively, with a specificity of 94% and 97%, respectively.¹³ When used together the sensitivity and specificity of cotesting was 100% and 93%, respectively, but resulted in an increased number of colposcopies, which may be costly and add stress for the patient. Many countries are beginning to move away from cervical cancer screening with cytology or cotesting to programs built upon a foundation of primary HPV testing.

Primary cervical cancer screening with HPV testing

The knowledge that hrHPV is a more sensitive test for cervical cancer and its precursors, as well as the relatively lower sensitivity of cytology, is the foundation for transitioning from primary screening with cervical cytology to primary screening with HPV testing. In the Netherlands¹⁴ and Australia^15,16 HPV testing with reflex cytology is the nationwide approach to cervical cancer screening. The basic components of the Dutch primary HPV screening program, as explained by Dr. Lai van Zulyan Mandres, are¹⁴:

1. Samples are collected by a general practitioner and sent to one of 5 central testing facilities for DNA testing for hrHPV.
2. If all previous samples tested negative, the screening occurs at ages 30, 35, 40, 50, and 60 years, a minimum of 5 screens per woman.
3. If there is a history of a previously positive hrHPV, the screening is intensified, with additional specimens collected at ages 45, 55, and 60 years.
4. If the sample is hrHPV negative, the patient continues screening at the standard intervals. No cytology testing is performed.
5. If the sample is hrHPV positive, reflex cytology is performed using the original collected sample. If the cytology shows no intraepithelial lesion or malignancy (NILM), another specimen is obtained for cytology within 6 months. If the second cytology specimen shows atypical squamous cells of undetermined significance (ASCUS) or a more worrisome cytology finding, the patient is sent for colposcopy. If two NILM cytology specimens have been obtained, the patient resumes primary hrHPV screening every 5 years.
6. If the specimen is hrHPV positive and cytology is ASCUS or more worrisome the patient is referred for colposcopy (FIGURE).¹⁴ The Dutch estimate that primary hrHPV screening will reduce the number of cervical cytology specimens by 90% annually.

Australia also has implemented nationwide primary HPV testing for cervical cancer screening. This change was implemented following a 10-year program of universal school-based vaccination of girls and boys, and biennial cytology screening for all women. The Australian screening program initiates hrHPV testing at age 25 years and thereafter every 5 years until age 74. If the hrHPV test is positive, reflex testing for HPV types 16 and 18 are performed on the original specimen along with cervical cytology. Women who test positive for HPV 16 or 18 are immediately referred for colposcopy. If the hrHPV test is positive and reflex testing for HPV 16 and 18 is negative, cervical cytology demonstrating ASCUS, low- or high-grade squamous intraepithelial lesions, or more worrisome results trigger a referral for colposcopy. The Australian program supports testing of self-collected vaginal samples for women who are underscreened or have never been screened.^15,16

Read about Pros and cons of switching approaches