A cone biopsy is an extensive form of a cervical biopsy. It is called a cone biopsy because a cone-shaped wedge of tissue is removed from the cervix and examined under a microscope. A cone biopsy removes abnormal tissue that is high in the cervical canal. A small amount of normal tissue around the cone-shaped wedge of abnormal tissue is also removed so that a margin free of abnormal cells is left in the cervix.

A cone biopsy can:

• Remove a thin or a thick cone of tissue from the cervix, depending on how much tissue is needed for examination.
• Be used to diagnose and sometimes to treat abnormal cervical tissue. The abnormal tissue is removed and sent to a lab for examination.

A sample of tissue can be removed for a cone biopsy using:

• A surgical knife (scalpel).
• A carbon dioxide (CO₂) laser.
• Loop electrosurgical excision procedure (LEEP).

How it is done

A cone biopsy is usually done as an outpatient procedure (you do not have to spend a night in the hospital).

The hospital or surgery center may send you instructions on how to get ready for your surgery or a nurse may call you with instructions before your surgery.

You will need to take off your clothes below the waist and drape a paper or cloth covering around your waist. You will then lie on your back on an examination table with your feet raised and supported by footrests (stirrups). Your health professional will insert an instrument with curved blades (speculum) into your vagina. The speculum gently spreads apart the vaginal walls, allowing the inside of the vagina and the cervix to be examined.

Medication that makes you unconscious (general anesthetic) or that makes the entire genital area numb (regional anesthesia, such as a spinal or epidural) may be used.

A cone biopsy using LEEP may be done in your health professional's office with an injected medication that numbs the cervix (cervical block). If a cervical block is used, an oral pain medication or pain medication given into a vein (intravenous, or IV) may be used in addition to the local anesthetic.

What To Expect After Surgery

Right after surgery, you will be taken to a recovery area where nurses will care for and observe you. Usually you will stay in the recovery area for 1 to 4 hours, and then you will go home. In addition to any special instructions from your doctor, your nurse will explain information to help you in your recovery. You will usually go home with a sheet of care instructions and who to contact if a problem arises.

Most women are able to return to their normal activity level in 1 week.

After a cone biopsy

• Some vaginal bleeding is normal for up to 1 week.
• Some vaginal spotting or discharge (bloody or dark brown) may occur for about 3 weeks.
• Sanitary napkins should be used instead of tampons for about 3 weeks.
• Sexual intercourse should be avoided for about 3 weeks.
• Douching should not be done.

When to call your health professional

Call your health professional for any of these symptoms:

• A fever
• Moderate to heavy bleeding (more than you would usually have during a menstrual period)
• Increasing pelvic pain
• Bad-smelling or yellowish vaginal discharge, which may indicate an infection

Why It Is Done

A cone biopsy may be done after a Pap test indicates moderate to severe cell changes and:

• The abnormal tissue cannot be seen with colposcopy but was found in cells collected from a biopsy of the cervical canal, or the abnormal tissue seen with colposcopy extends high into the cervical canal. A cone biopsy is done to remove and examine the abnormal tissue.
• The abnormal cells found on a Pap test cannot be seen with colposcopy or found in cells collected from a cervical biopsy. The cone biopsy may be used to diagnose the cause of the abnormal cell changes and remove the abnormal tissue at the same time.
• Cervical cancer is suspected based on Pap test results, colposcopy, and cervical biopsy. A cone biopsy can determine the extent, depth, and severity of the cancerous tissue and can guide treatment decisions.

How Well It Works

The cone biopsy may remove all of the abnormal tissue. This would mean that no further treatment is needed other than follow-up Pap tests.

The edges of the cervical tissue removed by a cone biopsy may contain abnormal cells, meaning that abnormal tissue may be left in the cervix. The cone biopsy may be repeated to remove the remaining abnormal cells. If follow-up tests show normal cells, then no further treatment may be needed. If abnormal cells remain, you and your health professional may discuss other treatments, such as removal of the uterus (hysterectomy).

The cone biopsy may show cancer that has grown deep into the cervical tissue (cervical cancer). Further treatment, such as surgery, radiation, or chemotherapy, will be recommended.

Risks

A cone biopsy is a surgical treatment with some risks.

• After surgery, a small number of women (less than 10%) may have bleeding that requires vaginal packing or a blood transfusion.¹
• Narrowing of the cervix (cervical stenosis) that causes infertility may occur (rare).
• Inability of the cervix to remain closed during pregnancy (incompetent cervix) may occur, causing pregnancies to end in miscarriage or premature labor (rare).

What To Think About

Cone biopsy (conization) can be done using a carbon dioxide laser or loop electrosurgical excision procedure (LEEP). One possible disadvantage of these methods is that the abnormal tissue at the margin with the normal tissue can be changed by the heat from the laser beam or the wire loop. This may make the laboratory study of the biopsied tissue more difficult.

If you have a cone biopsy, you need regular follow-up Pap tests and colposcopic examinations. A Pap test should be repeated every 4 to 6 months or as recommended by your health professional. Once several Pap test results are normal, you and your health professional can decide how often to schedule future Pap tests.

The healing and scarring process after a cone biopsy may make it difficult to identify abnormal tissue in the future.

Complete the surgery information form (PDF)(What is a PDF document?) to help you prepare for this surgery.

Citations

1. Nuovo J, et al. (2000). Treatment outcomes for squamous intraepithelial lesions. International Journal of Gynecology and Obstetrics, 68(1): 25–33.