What Is a Cone Biopsy?

A cone biopsy, also called conization, is a surgical procedure that is used to remove a cone-shaped piece of tissue from the cervix and cervical canal. Cone biopsy is useful when diagnosing or treating cervical intraepithelial neoplasia (CIN), a precancerous condition, or cervical cancer.

Doctor discussing cone biopsy with patient
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Purpose of Test

There are a few reasons why your doctor may order a cone biopsy. In some cases, the procedure is recommended if a woman has Pap smear results indicating there are abnormal cells in the cervix, followed by a colposcopy and an endocervical curettage (cells scraped from cervical canal) or punch biopsy (small sample of cervical tissue is removed) that is inconclusive. In this case, the cone biopsy can be used to check for precancerous or cancerous cells on your cervix.

In other cases, a cone biopsy may be used to evaluate the extent of cervical cancer that is already diagnosed.

Cone biopsy may also be used to remove tissue from the cervix as part of treatment for precancerous lesions or the earliest forms of cancer. It is considered a potential treatment for the following:

  • Cervical intraepithelial neoplasia (CIN): abnormal cells on the surface of the cervix
  • Carcinoma in situ (CIS): abnormal cells that have not moved beyond the place where they formed; sometimes referred to as stage 0 disease or CIN 3 (grade 3, severely abnormal cells)
  • Stage IA1 cervical cancer: a very small amount of cancer that has a maximum depth of 3 millimeters (mm)
  • Stage 1A2 cervical cancer: a very small amount of cancer that has a depth that's greater than 3 mm but no more than 5 mm

A cone biopsy may be the preferred treatment for women with the earliest stages of cervical cancer (IA1, IA2) who want to preserve their fertility after cancer treatment.

If the edges of the biopsy have cancer cells, the cone biopsy may need to be repeated or a radical trachelectomy (removal of the cervix as well as upper vagina and nearby tissue) may be considered.

There are three approaches to performing a cone biopsy:

  • Laser surgery, which uses a laser beam to excise a portion of tissue
  • Loop electrosurgical excision (LEEP), which employs a thin wire loop attached to a generator to electrically remove a piece of tissue
  • Cold knife conization (CKC) in which a surgical scalpel is used to remove tissue

Risks and Contraindications

The cone biopsy procedure is usually well tolerated. Your doctor will explain the short-term and long-term risks associated with the procedure, but it can be helpful to have an idea of what those might be so that you can be prepared ask any specific questions.

Potential short-term risks include:

  • Infection
  • Inadequate removal of tissue
  • Bleeding
  • Blood clots

While some vaginal bleeding and/or bloody discharge is common, excessive bleeding rarely occurs. Infection is sometimes possible and is usually characterized by a yellow or green discharge with a foul smell.

After any surgical procedure, there is always a small risk of blood clots in the legs. While this is uncommon with a cone biopsy, it's important be aware of it if you have an increased risk for blood clots.

If the cone biopsy did not remove all of the abnormal tissue, a repeat cone biopsy may be performed or additional treatments may be recommended.

Long-term risks after the procedure may include:

  • Persistence of human papillomavirus (HPV) infection: HPV infection, associated with cervical cancer, may persist, especially in women who have high-risk HPV strains (particularly type 16) as well as high HPV viral loads. In a review of studies, the incidence of persistent HPV infection was found to be 42% with LEEP and 7% with CKC.
  • Recurrence of abnormal cervical cells (dysplasia): The risk tends to be lowest for cold knife conization (less than 2%) when compared to LEEP and cryosurgery (use of cold to destroy abnormal tissue).
  • Preterm delivery: This is uncommon but can happen as a result of a cone biopsy. A 2016 study suggested that the risk following cold knife conization was higher compared to LEEP or cryosurgery. It's important to note, however, that untreated dysplasia (such as CIN 2 or CIN 3) is also associated with premature delivery. If an incompetent cervix occurs, a procedure called a cerclage is sometimes used, in which the cervix is essentially "sewn shut."
  • Inconclusive Pap smears: Cone biopsy may make it harder to interpret future Pap smears.
  • Cervical stenosis: Scarring and narrowing of the cervix may result in sperm being unable to pass through the cervix, and subsequent infertility.

These factors reinforce the importance of consistent, routine follow-ups with your health provider as well as ensuring that any obstetric or gynecologic specialist knows all the details of your medical history.

Contraindications

Contraindications, or reasons the procedure should not be performed, include severe cervicitis (inflammation of the cervix), or, in the case of LEEP, the presence of a demand cardiac pacemaker.

Relative contraindications (which mean the risks and benefits must be weighed for each woman) include pregnancy, a history of bleeding disorders, blood clots, or the use of blood thinners.

Before the Test

At an appointment prior to the surgery, your doctor will explain the procedure and give you a chance to ask any questions. They will discuss which anesthesia will be best for you, whether general or regional.

At that time, tell your doctor if you’re pregnant or think you might be. Also, let your doctor know about any allergies or if you have a bleeding disorder that can affect healing.

Your doctor will also need to know about any medications, either over-the-counter or prescription, or herbal supplements you take, in case there are any that you should discontinue until after your cone biopsy.

Preparations for the procedure include the following:

  • Check with your health insurance to determine how much of the cost is covered before undergoing the procedure.
  • Abstain from sex and using tampons, vaginal creams or medications, and douching for at least 24 hours prior to the procedure.
  • Abstain from eating or drinking for six to eight hours before the procedure due to the anesthesia.
  • Arrange for someone to drive you home afterward, because the anesthesia can make you feel weak and tired after the procedure.
  • Bring all medical paperwork and health insurance cards to the hospital.
  • Bring a sanitary pad to use after the procedure.

During the Test

Cone biopsies typically are performed in a hospital or a surgery center, usually by an obstetrician-gynecologist. A cone biopsy takes about 15 minutes. However, you should plan to be at the hospital for several hours, as you'll need time to fill out forms and for pre- and post-operative care.

On the day of your cone biopsy, your health care team will include a preoperative nurse, an anesthesiologist or nurse anesthetist, and your obstetrician-gynecologist. They can answer any questions you may have before the procedure.

Pre-Test

When you get to the hospital, the preoperative nurse will conduct an exam and make sure you’ve had all the needed tests prior to the procedure. After you change into a hospital gown, you may be given a blanket to keep warm.

An anesthesiologist will talk to you about your medical history. Anesthesia is either given intravenously (through a needle into a vein) or through a mask. You and your doctor will decide beforehand whether you should be given general anesthesia or medicines to help you relax and stay sleepy.

For the procedure you'll be lying on your back with your feet in stirrups to keep your legs apart and provide access to your cervix. The doctor will insert a lubricated tool called a speculum into your vagina to widen it. If a LEEP biopsy is performed, you may be injected with a medication to numb the cervix.

Throughout the Test

During the procedure, the surgical team will monitor your vital signs to make sure that everything is going smoothly.

Whatever method is used to excise a sample, the amount of tissue collected will likely measure around 1.5 centimeters (cm) wide and 1 cm deep. Later, that sample of tissue is analyzed with a microscope to determine whether it has cancerous cells or precancerous cells.

Post-Test

After a cone biopsy, your cervix may be packed with a pressure dressing. Your doctor will give you instructions on when and how to remove it.

Expect to spend three to four hours in the recovery room before you're allowed to leave the hospital or surgical center. Again, you will need to have someone drive you home or arrange to be picked up by a cab or car service.

After the Test

It will take four to six weeks for your cervix to heal after the procedure. Follow your doctor’s instructions for at-home care, which may include:

  • Take showers instead of baths: Don’t soak in water, including hot tubs and swimming pools.
  • Avoid strenuous physical activity: This includes vacuuming, yard work, or carrying heavy groceries and laundry.
  • Don't lift anything over 10 pounds: The strain could increase your bleeding.
  • Do not use tampons or douches or have sexual intercourse: Any of these could prolong the amount of time it takes your cervix to heal and increase the chance of infection.

Managing Side Effects

Recovery varies from person to person. You may feel tired and have abdominal cramping for a couple of days after having a cone biopsy. You may also have bloody discharge for two to three weeks after the procedure. You’ll probably need to wear sanitary pads during this time.

Your doctor can advise you about what medicines you can take for pain relief.

While your doctor will likely recommend that someone stay with you for 24 hours following the procedure, you should consider having a friend or family member stay with you for several days if you live alone to help with any heavy lifting and chores.

Seek urgent medical care if you experience any of the following symptoms after a cone biopsy:

  • Persistent pelvic pain
  • Heavy bleeding
  • Foul-smelling discharge
  • Chills
  • Fever greater than 101 F
  • Pain, redness, or swelling in one or both of your legs

In addition, if you have any sudden symptoms after the cone biopsy that seem alarming to you, it's important to contact your physician or seek urgent medical attention.

Interpreting Results

You will likely get the results of your cone biopsy within five to seven business days. A normal result means there are no precancerous or cancerous cells in the cervix.

Abnormal results mean that precancerous or cancerous cells have been detected. Precancerous cells fall into these categories:

  • CIN 1: Slightly abnormal cells, also called low-grade or mild dysplasia. These often go away without treatment but can become cancerous in some instances.
  • CIN 2: Moderately abnormal cells, also called high-grade or moderate to marked dysplasia. For roughly 50% of women, the changes will regress, while for others, the changes may remain the same or progress without treatment. CIN 2 is not cancer, but may become cancer if not treated.
  • CIN 3: Highly abnormal cells that may be classified as high-grade or severe dysplasia or carcinoma in situ. CIN 3 is considered a direct precursor to cancer, and if not treated, it may become cancer.

In each case, your doctor will let you know whether the cone biopsy was able to remove all the abnormal tissue.

Follow-Up

You will likely be instructed to schedule a follow-up appointment for around four weeks after your procedure.

Further treatment and future monitoring will depend on the results of your cone biopsy.

If the biopsy shows that there may still be abnormal cells, the cone biopsy may need to be repeated or your doctor may discuss other options, such as a radical trachelectomy or hysterectomy.

If the cone biopsy removes all of the abnormal tissue, you will still need to be monitored, with the frequency of monitoring dependent on your results as well as your age, pregnancy status, whether you have a persistent HPV infection, and your history of abnormal Pap smears in the past.

Most often, HPV testing will be recommended in six months, and if normal, will be followed by yearly testing (either HPV testing or a combination of a Pap smear and HPV testing) until you have at least three consecutive negative tests.

Long-term monitoring is important as well. Once you have completed the recommended short term follow-up, this usually means either HPV testing or a combination of a Pap smear and HPV testing every three years for at least 25 years.

A Word From Verywell

It’s normal to feel anxious or worried when waiting for or receiving test results. To ease your nervousness, turn to trusted family members, friends, and, of course, your doctor. Don't hesitate to ask them any and all questions you have before your procedure. And if you're in doubt about whether you need a cone biopsy, feel free to get a second opinion.

It can also be helpful to reach out to someone else who's had a cone biopsy, but be selective. As with other fields of medicine, cone biopsies are constantly improving. The chance that your procedure will be effective and without complications is higher than for someone who may have had the procedure in the distant past.

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Article Sources
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