Regular screenings play a vital role in helping women prevent cervical cancer, which used to be one of the most common causes of death for women in the United States.
However, many women may wonder which tests they need and how often to get them. The guidelines were recently updated, with important new recommendations about Pap smears, human papillomavirus (HPV) tests, and pelvic exams.
To eliminate the guesswork, MSK’s Deborah Goldfrank explains the current recommendations and which tests women need — and don’t need. Dr. Goldfrank is a surgeon and Head of Memorial Sloan Kettering’s General Gynecology Department.
What is the difference between a Pap test, an HPV test, and a pelvic exam?
The Pap test, also called a Pap smear, and the HPV test both look for changes in cells of the cervix that may turn into cancer or make a woman more likely to develop cancer. Both require taking a small sample of cells from the cervix, putting them into a liquid, and then testing the cells.
The Pap test was a huge advance in women’s health. But it came out before we understood the role of HPV in cervical cancer. Most cervical cancer is caused by HPV, which is widespread in both men and women. Because the HPV test looks specifically for the presence of the virus, it is a very helpful screening test to predict who is at risk of developing cervical cancer.
A pelvic exam involves an internal manual exam to assess organs, including the uterus, the ovaries, and the pelvis. A Pap test and HPV test could be done at the same doctor’s visit as a pelvic exam.
What are the current recommendations for Pap and HPV tests?
In August 2018, the US Preventive Services Task Force issued new guidelines that got a lot of attention. Most groups focusing on gynecologic health, including MSK, have the same recommendations. They are:
- Women 21 to 29 should be screened every three years with a Pap test only.
- Women 30 to 65 should be screened every three years if the Pap test is used alone and every five years if the HPV test is used in combination with the Pap test.
- Women over 65 do not need to be screened if they have been screened according to the guidelines before they reached 65 and are otherwise not at a high risk for cervical cancer.
- Women who have a compromised immune system, who have had precancerous lesions, or whose mothers used the drug diethylstilbestrol when they were pregnant should be screened more often.
Why should women between ages 21 and 29 get only a Pap test but women between ages 30 and 65 get a Pap test and an HPV test?
Most women and men under the age of 30 have been exposed to HPV. For most people, the virus will be suppressed by their immune system within a few years and won’t turn into cancer.
So we test women under 30 with the Pap test only to see if their cervix is undergoing unusual changes that could become cancer. If we used the HPV test too, most women under 30 would undergo unnecessary procedures to test and treat the virus, which for most of them will not turn into cancer. That would be overtreating women and could do more harm than good.
In women from ages 30 to 65, the presence of HPV at the cervix is more likely to turn into cancer. So having the greater sensitivity of the HPV test in that age group is important.
What should women over 65 know about Pap smears and HPV tests?
The guidelines don’t find strong evidence that Pap smears and HPV tests help prevent cervical cancer in women over age 65. However, that is true only for women who have been screened regularly and are not at risk otherwise. This recommendation does not mean that all women over 65 should stop screening.
What should women over 65 know about pelvic exams?
Women should discuss this with their doctor. There is strong evidence that Pap tests and HPV tests help prevent cancer. But for pelvic exams, the research just hasn’t been done to prove that they save lives, despite being the standard of care in the past.
Many women find them invasive. But some doctors feel they are helpful as part of an annual visit. They can reveal some issues that develop over time.
If a woman has received the HPV vaccine, does she still need to follow the cervical cancer screening guidelines?
Yes. There are many types of the HPV virus. The current vaccine protects against nine, including the two types responsible for most cervical cancers, which are HPV 16 and 18. These, along with other HPV types that can make it more likely for a woman to develop cervical cancer, are called high-risk types of HPV.
It’s also important that children receive the HPV vaccine, preferably before age 13. It is very effective at preventing cervical cancer, as well as anal cancer, some head and neck cancers, vaginal cancer, and penile cancer. This vaccine is safe and easy to receive.
What if a woman is tested and is found to have the high-risk types of the virus?
That happens frequently. If a woman is HPV positive, we recommend that she is screened more closely. If she has HPV 16 or 18, we recommend a colposcopy, which uses a kind of microscope to look closely at the cervix. We may also take a small tissue sample, called a biopsy, for more testing. We’ll then follow closely to see if there are changes to the cells of the cervix or if the situation resolves itself and the virus is suppressed by the immune system, which often happens.