Cervical cancer starts in the cervix, which is the passageway between the vagina and the uterus. Cervical lesions are patches of abnormal cells growing on the cervix.

Sometimes, cervical lesions are made of precancerous cells. Other times, cervical lesions contain cancerous cells.

Thanks to regular screening methods, cervical cancer is not as common as it used to be. The National Cancer Institute estimates that 14,100 people in the United States will be newly diagnosed with cervical cancer in 2022. This will make up about 0.7 percent of all new cancer diagnoses.

Keep reading to learn about the different types of cervical cancer lesions and how they’re diagnosed and treated.

Precancerous cervical lesions happen when cells in the cervix begin to develop abnormal changes. This means they have the potential to develop into cancerous lesions.

Most precancerous cervical lesions go away on their own, without causing any problems. But in some people, these precancerous lesions develop into cancer. Treating precancerous lesions can prevent cervical cancer.

A doctor might use a variety of medical terms when talking about precancerous cervical lesions, including:

  • cervical dysplasia
  • cervical intraepithelial neoplasia (CIN)
  • squamous intraepithelial lesion (SIL)

When examined under a microscope, precancerous cervical lesions are classified into one of three categories. These categories depend on how much of the cervix appears abnormal:

  • CIN1 (mild dysplasia): Only a few of the cells appear abnormal. This type will often go away on its own without treatment.
  • CIN2 and CIN3 (moderate dysplasia): More of the cells are abnormal. Because this type sometimes goes away on its own, you may choose to get regular screenings instead of treatment after talking with your doctor.
  • High grade SIL (severe dysplasia): This is the most serious type. It needs to be treated right away.

Cancerous cervical lesions are classified according to the location of the cancerous cells. These can include cells of the:

  • Exocervix: This is the outer part of your cervix that faces down into your vagina. It’s the part that a doctor looks at as a part of a pelvic exam. The cells of the exocervix are called squamous cells.
  • Endocervix: This is the inner part of your cervix that faces up toward the uterus. The cells here are called glandular cells.

As such, the main types of cervical cancers are:

  • Squamous cell carcinoma: Squamous cell carcinoma begins in the cells of the exocervix, often at the meeting point between the exocervix and endocervix.
  • Adenocarcinoma: Adenocarcinoma begins in the glandular cells of the endocervix.
  • Adenosquamous carcinoma: Adenosquamous carcinoma affects both squamous and glandular cells in the cervix.

Overall, squamous cell carcinoma is the most common type of cervical cancer. According to the American Cancer Society, it accounts for 9 out of 10 cervical cancers.

The main cause of cervical lesions is an infection with human papillomavirus (HPV). According to the Centers for Disease Control and Prevention (CDC), HPV causes more than 9 out of 10 cervical cancers.

Not all types of HPV can cause cervical cancer. There are about 14 types of HPV that are considered high risk and are responsible for the majority of cancers that are caused by HPV.

HPV infection is very common. Most people contract HPV at some point after becoming sexually active. While the immune system typically clears the infection, sometimes high risk types of HPV can remain and lead to cancer.

The good news is that cervical cancer is now a very preventable cancer because of the HPV vaccine. A 2020 study found that, when given before age 17, the HPV vaccine reduced the risk of cervical cancer by almost 90 percent.

Cervical cancer risk factors

In addition to HPV infection, other risk factors for cervical cancer are:

  • having a family history of cervical cancer
  • smoking
  • having a weakened immune system
  • taking birth control pills for a long time
  • currently or previously having chlamydia, a sexually transmitted infection (STI)
  • factors related to pregnancy, such as being 17 years or younger at the time of your first full-term pregnancy or having three or more full-term pregnancies
  • factors related to sexual history, which can raise the risk of contracting HPV, such as:
    • having had many sexual partners
    • becoming sexually active at a younger age
    • having a sexual partner who has a known HPV infection or who has had many sexual partners

Cervical cancer screening is vital in preventing cervical cancer. This can include an HPV test, a Pap test, or both.

The HPV test uses a sample of cervical cells to test for HPV. While it doesn’t specifically detect cervical lesions, it can alert your doctor to the presence of a high risk type of HPV that could lead to precancerous or cancerous changes in the future.

A Pap test also uses a sample of cells collected from the cervix. The cells are examined under a microscope to check for abnormal changes.

The current American Cancer Society cervical cancer screening guidelines are that all people with a cervix between the ages of 25 and 65 get a primary HPV test every 5 years.

If HPV primary testing isn’t available, HPV-Pap co-testing every 5 years, or a Pap test every 3 years, may also be used.

What if my screening result is abnormal?

If the results of your HPV or Pap test come back abnormal, your doctor may do a colposcopy or cervical biopsy. These are two procedures that let them examine the cells of your cervix more closely to check for precancer or cancer.

During a colposcopy, a doctor uses a speculum to open the vagina so they can see the cervix. They then insert a device called a colposcope that has a light and a magnifying glass to help them get a better view of the cervix.

It’s possible that a biopsy may be taken during the colposcopy. In a biopsy, a small sample of cervical cells is removed. The sample is then examined in a lab for signs of precancerous or cancerous cells.

Symptoms of cervical lesions

Precancerous cervical lesions often don’t cause symptoms. Because of this, many people don’t know they have them.

The same can be said about early cancerous lesions. Overall, most people with cervical cancer don’t have symptoms until the cancer has become more advanced. Some of the most common symptoms can include:

The fact that precancerous and early cervical cancer lesions don’t typically lead to symptoms makes regular cervical cancer screenings very important for early detection.

For some people, precancerous cervical lesions will go away without treatment. However, if you do have precancerous cervical lesions, getting treatment can go a long way in preventing them from becoming cancerous in the future.

Treatment involves removing the precancerous lesions. This can be accomplished in a few ways.

Ablation-based treatments work by destroying precancerous lesions. This can be done using cold (cryotherapy) or heat (laser surgery).

Excisional treatments remove the precancerous lesions. This can be done with a scalpel that removes a cone-shaped section of tissue (cold knife conization) or by using a thin wire loop containing an electrical current (LEEP).

It takes a long time to develop cervical cancer. According to the World Health Organization (WHO), it can take 15 to 20 years for cervical cancer to develop.

However, the WHO also notes this time frame is different for people with weakened immune systems. This can include people who are:

In people with a weakened immune system, the WHO states cervical cancer can develop in a shorter span of time — about 5 to 10 years.

Precancerous cervical lesions are abnormal changes in cells of the cervix that are not yet cancerous. Some precancerous lesions go away on their own. Others will need to be treated to prevent cancer from developing.

Cervical lesions are mainly caused by HPV infection. Screening tests can detect HPV as well as abnormal changes to cervical cells. An HPV vaccine is available that can greatly reduce the risk of HPV infection and cervical cancer.

It’s not common for precancerous or early cancerous cervical lesions to cause symptoms. This makes regular cervical cancer screenings all the more vital for detecting and treating these lesions early.