Introducing the Self-Collection Test
The Food and Drug Administration (FDA) approved self-collection as a method to detect human papillomavirus (HPV) — the leading cause of cervical cancer — in May. Screening tests are designed to identify individuals at high risk of cancer or precancer, not to diagnose the disease. With the introduction of these tests, the U.S. joins countries like Australia, Canada, the Netherlands, Denmark, and Sweden, where self-swabbing for HPV is already widely practiced.
Currently, these samples, collected from the vaginal canal, must still be gathered in healthcare settings such as doctor's offices. While some countries have approved at-home self-sampling for HPV, this method is still pending FDA approval in the U.S.
Understanding HPV and Its Link to Cervical Cancer
HPV is a common sexually transmitted infection, primarily spread through sexual intercourse or skin-to-skin contact. Most sexually active individuals will contract at least one type of HPV during their lifetime, but the infection usually resolves on its own.
Among the more than 30 types of HPV that can infect the genitals, only a small number are considered "high-risk" and associated with cancer. Low-risk HPV typically has no symptoms and clears up on its own, although it can sometimes cause genital warts. High-risk HPV, however, can lead to abnormal cell growth if it persists, which may eventually become cancerous.
The HPV vaccine can protect against most cases of cervical cancer. A 2024 study in the Journal of the National Cancer Institute reported zero incidences of invasive cervical cancer among young Scottish women who had received at least one dose of the HPV vaccine. Women who had received three doses — the generally recommended number — were significantly less likely to develop cervical cancer compared to unvaccinated women.
While there is no cure for high-risk HPV, abnormal cervical cells can be removed before they turn into cancer.
What Do Cervical Cancer Screening Tests Look For?
There are two primary methods for checking for cervical cancer: the HPV test and the Pap test.
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HPV Test: Detects the genetic material of high-risk HPV strains that can cause cancer if left untreated.
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Pap Test: Also known as a Pap smear or cervical cytology, this test checks for changes in cervical cells that could lead to cancer. These changes include abnormalities in the cell nucleus, which contains the cell's DNA.
An HPV test can also be performed alongside a Pap test in what's called a co-test. The combined test can detect high-risk HPV and cervical cell changes using the same sample. Recommendations for who should get which test and how often vary by age and other health factors.
It's important to note that these are not diagnostic tests. Instead, they identify individuals at high risk for developing cancer or precancer. A positive result on any of these tests would require further testing, often a colposcopy-directed biopsy, to confirm a diagnosis.
How Do the New Self-Collection Tests Work?
If opting for the new self-collection tests, patients will receive instructions from their medical provider. The test is completed in the clinic, but no medical supervision is required during the self-collection process. Essentially, a doctor doesn't need to be present when the sample is collected.
Patients are generally instructed to insert a long cotton swab into the vagina and gently swirl it for 20 to 30 seconds to collect an adequate sample. The sample is then left at the healthcare provider's office and sent to a lab for analysis.
Advantages of Self-Collection Compared to Pap Smears
The new self-collection option has the potential to increase the number of people who get cervical cancer screenings across the U.S. These tests are more convenient and less invasive than traditional screening methods, potentially reaching patients who may avoid Pap tests for various reasons.
For many patients, screenings involving a speculum can cause physical and emotional discomfort. This is particularly true for patients with a history of sexual violence, older patients with more sensitive vaginal tissues, and individuals with gender dysphoria.
Are There Any Downsides to Self-Collection Tests?
A meta-analysis of studies published in Nature found that self-collected vaginal samples are comparable to cervical samples collected by a doctor in terms of their ability to detect HPV. One study in the analysis found that tests using self-collected samples were about 89% accurate at detecting HPV, while doctor-collected samples had an accuracy of nearly 88%.
However, patients may have concerns about self-collection. These concerns often revolve around performing the test correctly and obtaining a sufficient sample. Although self-collection is somewhat susceptible to user error, the method is highly sensitive. Even if a patient collects only a small number of cells, the tests can adequately detect HPV.
Who Should Be Screened for Cervical Cancer and How Often?
The American Cancer Society (ACS) recommends that regular cervical cancer screenings begin at age 25. These guidelines are the most up-to-date, as recommendations from the U.S. Preventive Services Task Force are currently being revised.
According to the ACS guidelines:
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Adults with a cervix aged 25 to 65 should have a primary HPV test every five years. A primary HPV test checks for HPV alone and is not combined with a Pap test.
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Alternatively, a co-test, which combines an HPV test and a Pap test, can be done every five years.
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Or, a Pap test alone can be done every three years.
Primary HPV tests are the gold standard for preventing cervical cancer, as they are better than Pap smears at identifying precancerous changes in cervical cells.
More frequent screening may be recommended for patients with a personal or family history of cervical cancer or those with HIV or a compromised immune system. The key takeaway is to get screened regularly and follow through with recommended follow-up tests to catch abnormalities early when treatment is most effective.
