A Pap test and HPV test both check for signs of cervical cancer. What’s the difference?
A Pap test checks for abnormal cervical cells in the cervix that could lead to cervical cancer if left untreated.
An HPV screening checks for high-risk types of HPV that are more likely to cause pre-cancers of the cervix, which is part of a woman’s reproductive system.
Both tests can also find cervical cancer at an early stage when treatment can be highly successful.
“Screening saves lives,” says Maria Murillo, MD, an OB-GYN at Scripps Clinic in North County. “Cervical cancer used to be one of the leading causes of death for women in the United States, but the death rate has significantly dropped in recent decades due to more women getting screened for cervical cancer.”
The main cause of cervical cancer — one of the main types of gynecological cancers — is infection with human papillomavirus (HPV) — the most common sexually transmitted infection. Only a small number of women with high-risk types of HPV will develop cervical cancer.
Pap test and HPV test are both effective screening tools for cervical cancer. For many years, the Pap test was the only method for cervical screening. HPV testing added a second option. A third option is Pap/HPV co-testing, which checks the same cell sample for high-risk HPV types and abnormal cervical cell changes.
The American Cancer Society, which updated its guidelines in 2020, recommends starting cervical screening at age 25 for women at average risk. Cervical cancer is very rare in women under age 25.
The ACS recommends the primary HPV test as the preferred test for cervical cancer screening for people 25 to 65 years of age. Co-testing with an HPV test and Pap test every five years or a Pap test every three years are considered acceptable options.
People 65 years or older should talk to their doctors to see if screening is still needed.
Doctors may recommend more frequent testing for women who have a history of cervical cancer, HIV or a compromised immune system.
Both tests can be done in a doctor’s office or clinic. During a screening, a physician takes a sample of cells from the cervix, and they are sent to be tested for abnormal cell changes or HPV, depending on the type of test.
If you test positive for HPV infection, your doctor will likely recommend monitoring the infection to see if it clears up on its own.
“It’s a common infection and most cases of HPV clear up on their own, but we want to know if you have it so we can keep an eye on any changes to the cells,” says Dr. Murillo.
The HPV vaccine is recommended during preadolescence to reduce the risk of developing HPV-related cancer.
A positive Pap test result means cell changes likely caused by HPV were found in the cervix.
“A positive Pap test does not mean you have cervical cancer,” Dr. Murillo says. “It means we found abnormal or unusual cells, and that could be due to several reasons. Usually, the first step is to repeat the test. If the result is still positive, we look into further testing.”
Treatment depends on whether there is pre-cancer or cancer, and if it has spread.
Precancerous cells can be removed before they can develop into cervical cancer. They may be treated with procedures using cold, heat, laser or surgery to remove abnormal cells. These treatments have a high success rate and can usually be performed in the doctor’s office on an outpatient basis.