ILLUSTRATIVE CASE
A 40-year-old woman presents to your office to establish care. During your interview you realize that she has never been screened for cervical cancer. In fact, she has not had a pelvic exam because she is fearful of the procedure. She would like to know if alternatives exist for cervical cancer screening. What can you suggest?
Although deaths from cervical cancer decreased in the United States from 1975 to 2017, demographic and social disparities in the burden of the disease remain.2,3 Data from 2016 reveal that cervical cancer incidence per 100,000 women is lowest among white (7.5), Asian-Pacific Islander (5.8), and American Indian/Alaska native (5.6) women, and highest among Hispanic (9.8) and black (8.7) women, which could be explained by lower screening rates in these populations.4,5 The National Cancer Institute’s publication on reducing cancer health disparities states that the most effective way to reduce cervical cancer incidence and mortality is by increasing screening rates among women who have not been screened or who have not been screened regularly.6
The US Food and Drug Administration (FDA) approved the first human papillomavirus (HPV) screening test in 2003.7 Evidence now suggests that high-risk HPV screening provides greater protection against cervical cancer than screening with cytology alone.8 The American College of Obstetricians and Gynecologists (ACOG) and the US Preventive Services Task Force (USPSTF) have changed their recommendations to include primary HPV testing as an alternative method to Pap smears for cervical cancer screening.9
An advantage of primary HPV screening is that it can be performed on a specimen collected by the patient, which could potentially increase rates of screening and help to decrease demographic and social disparities. A randomized trial of almost 2000 women ages 21 to 65 years that evaluated the acceptability of this method to patients revealed that more than half of women prefer the idea of a self-collected specimen to one that is collected by a clinician because it is more convenient and obviates the need for a pelvic exam.10
A meta-analysis of 36 studies and more than 150,000 women concluded that when self-collected samples were used with signal-based assays, the tests were not as sensitive or specific as when clinician-collected samples were used.11 However, the meta-analysis also found that some polymerase chain reaction (PCR)-based HPV tests were similarly sensitive for both self- and clinician-collected samples.
STUDY SUMMARY
PCR vs signal amplification HPV tests with collection by patients vs clinicians
This meta-analysis compared the accuracy of high-risk HPV self-screening with clinician collection of samples (56 diagnostic accuracy trials; total N not provided) in identifying cervical intraepithelial neoplasia grade 2 or worse (CIN 2+) with signal amplification and PCR tests evaluated separately.1 In addition, this review evaluated strategies to screen women who are underscreened or not screened, which was defined as women who were irregularly or never screened, or did not respond to reminder letters about cervical cancer screening (25 randomized controlled trials [RCTs]; total N not provided).
In the diagnostic accuracy studies, patients collected a vaginal sample themselves and then had a sample taken by a clinician. CIN 2+ or 3+ was confirmed by either colposcopy and biopsy performed on all patients or by a positive high-risk HPV test result. Studies were further divided into those using assays based on signal amplification or PCR.
Continue to: In signal amplification assays...
