Definition & Overview
A vulvar biopsy is a diagnostic procedure performed to determine whether there are lesions in the vulvar epithelium, what caused them, and whether these lesions can be excised and treated during the same session. If the lesion cannot be treated yet, a biopsy will be conducted and the results will be used to plan succeeding treatments. This is a safe and simple procedure that can be performed in an office or clinic setting and is one of the most common gynecological in-office procedures.
Who should undergo and expected results
A vulvar biopsy is prescribed for women who:
- Have visible lesions
- Are suspected of having a malignant condition
- Have lesions that do not respond to standard therapy
- Have lesions in a vascular pattern
- Have white lesions that do not respond to empiric treatment
- Have lesions that appear to be benign
A vulvar biopsy is usually performed when the vulvar lesions and other changes in the vulva are not sufficiently diagnosed using routine tests, which include medical history, physical examination, microscopic examination, culture test, or polymerase chain reaction tests. These can usually successfully diagnose lesions caused by candida vulvitis, contact dermatitis, and herpes simplex virus, but may not be adequate for diagnosing other conditions. The most common conditions that can only be successfully diagnosed with a biopsy include:
- squamous cell dystrophies
- lichen sclerosis
- invasive cancer of the vulva
- molluscum contagiosum
- vulvar intraepithelial neoplasia
- vulvar carcinoma
After a successful biopsy, the collected sample of lesion or tissue is placed under examination. If the lesion is small, it may be possible to completely excise it during the biopsy, and the removed lesion is simply tested for possible malignancy. If the lesion is large, a small tissue sample is taken for further analysis before any treatment is attempted.
How the procedure works
A vulvar biopsy is performed on the vulva, which is the entire female external genitalia that extends from the pubis to the perineal body. It's different structures are the labia majora, labia minora, hymen, and the clitoris. The vestibule, greater vestibular glands (also known as Bartholin's glands), and the minor vestibular glands are also included, and so are the urethral opening and the paraurethral glands. The doctor will begin by identifying the most appropriate sites for biopsy, taking into account the distance between the urethra and the rectum. This is an important preparatory step, as the exact site of biopsy will affect the chance of obtaining an accurate diagnosis and the risk of infection. Generally, however, the labia minora, clitoris, and urethra are not used as biopsy sites due to the high sensitivity of these areas. The rectum is also avoided as much as possible, as aftercare becomes more difficult if the rectum is involved; also, there will be a heightened risk of infection due to the rectum's proximity to bowel movement.
The procedure begins with the administration of local anesthetics using the smallest needle possible to minimize pain. The exact technique used to draw the actual sample, however, will differ depending on whether a Keyes punch biopsy or shave biopsy is used. A punch biopsy is used when there is suspicion of inflammatory disease, ulcer, pigmented lesions, and neoplasias, whereas multiple biopsies may be required when the lesions are bigger or are found in different parts of the external genitalia. Another way of determining the more appropriate type of biopsy is to match it with the appearance of the lesion; for lesions where depth is an issue, the Keyes punch method is preferred as it can perform biopsies for lesions as small as 2 to 10 mm. For small lesions, the puncture site may heal without the need for sutures. In such a procedure, the Keyes punch is placed against the lesion then rotated clockwise and counterclockwise so that it can penetrate the skin. Twisting motion and pauses should be avoided as these may produce shredded tissue samples.
On the other hand, a shave biopsy is performed by injecting an anesthetic underneath the lesion to take samples using a scalpel or scissors. When a scalpel is used, the lesion is elevated and removed with a single sweep using a 15-blade. When curved scissors are used, the lesion is first elevated then excised with the scissors pointed upwards. Scissors are best for lesions that need to be removed in depth.
During a vulvar biopsy, the skin of the vulvar region is treated no differently as the skin in other body parts; thus, it is expected to heal in the same manner. The patient will be allowed to take a shower 24 hours following the procedure, but hot baths should be delayed until the puncture site is completely healed. However, if the patient underwent a punch biopsy, the vulvar area may be comforted by soaking in sitz baths after the procedure and also after each bowel movement, to make sure that the biopsy site is not exposed to stool for a long time, a factor that may lead to an infection. The biopsy site should also be kept clean by washing the area once or twice each day, and should be dried after every washing. If there is still some bleeding, the patient can stop it with direct pressure.
However, the only difference in the healing process is that, given the location of the biopsy site and the presence of pubic hair in the area, it is usually hard to keep a post-procedure dressing in place, so dressings are usually not used. Sometimes, patients are only advised to use a pad or a panty liner instead.
Possible risks and complications
Prior to the procedure, the patient is informed of its complete benefits and risks, which include:
- Allergic reaction
- Failure of the procedure, which occurs when the sample taken is inadequate and which may result in a repeat procedure
These risks, however, may be controlled by avoiding sensitive areas when selecting the biopsy site, and by carefully following after-care instructions.
Fuh KC, Berek JS. Current management of vulvar cancer. Hematol Oncol Clin N Am. 2012;26:45-62.
Jhingran A, Russell AH, Seiden MV, et al. Cancers of the cervix, vulva, and vagina. In: Niederhuber JE, Armitage JO, Doroshow JH, et al., eds. Abeloff's Clinical Oncology. 5th ed. Philadelphia, Pa: Elsevier Churchill Livingstone; 2013:chap 87.