Psoriasis, a common skin condition, is often found on the elbows, knees, scalp, and nails. In psoriasis, the skin appears silvery with scaly patches. Psoriasis can occur in the vulva without affecting other areas of the body. The disorder occurs commonly on the labia majora and often spreads to the groin folds and the mons pubis.
Psoriasis lesions on the vulva can appear as they do on other areas of the body, or they can be salmon pink with a very well-demarcated edge. If the woman has psoriasis on other areas of the body, vulvar psoriasis is more likely to come to mind and be identified. A family, rather than a personal, history of psoriasis should also raise suspicion of vulvar psoriasis, but making the diagnosis can be difficult without the aid of a biopsy.
Neoplasias include vulvar intraepithelial neoplasia (VIN); squamous cell carcinoma of the vulva; and anal cancers, which arise from HPV. VIN is not cancer but may develop into an invasive cancer if not treated. It can occur anywhere on the vulva or around the anal area.
Diagnosis of VIN is challenging, as it can manifest as a single lesion or multiple lesions that vary in color from white to brown to red and can be rough, smooth, flat, or raised. The lesions can be easily confused with condylomas or even a common mole. When an abnormal or new lesion is identified, vulvar biopsy is indicated
When to do a biopsy
A vulvar biopsy will help to identify or confirm your suspicions about a lesion or abnormality because histologic analysis can differentiate benign from neoplastic lesions. Biopsy that results in removal of the entire lesion can be a curative treatment as well as a diagnostic procedure. Clinicians tend to treat and re-treat rather than perform a biopsy to determine a diagnosis. More errors result from not doing a biopsy.
Consider a biopsy when you observe a pigmented lesion (white, red, or dark), skin texture that is rough or has heightened architecture, areas that appear to be altered or changed, and any obvious abnormal growth or lesion. If you are suspicious that a pigmented lesion might be a melanoma, referral to dermatology for biopsy is advised.
Another indication for vulvar biopsy is as an aid in treatment. If a woman has persistent symptoms or does not seem to respond to prescribed therapy, a biopsy might be necessary. Consider poor adherence to the prescribed treatment before deciding that the treatment was ineffective. A conversation with the woman will hopefully turn up issues with adherence.
Also review and rethink your original diagnosis. Reevaluate for infection and for irritant or allergic contact dermatitis. Consider the possibility that the original diagnosis was inaccurate or that there are multiple diagnoses.
Choosing the biopsy site
Once the decision has been made to obtain a biopsy, site selection is the most important decision that must be made. Look for areas of change. Examine the thickest portion of the lesion, the most irregular color change, or the edge of the lesion. If possible, remove the entire lesion. As previously noted, taking a biopsy sample from an area that is simply erythematous will likely show inflammation, which is apparent, and the results will not be specific enough to direct management.
If possible, avoid the clitoris, as the woman may experience postbiopsy neuropathic pain because of the high concentration of nerve endings in this sensitive area. The urethra is also an area to be avoided. If this is the area of concern, referral to a urogynecologist or urologist should be considered.
If the skin surface or mucous membranes appear normal in an area of perceived symptoms, such as pain or burning, biopsy is not necessary. In these cases, symptoms are usually neuropathic in origin. Often, clinicians will biopsy to prove to the patient that there is no abnormality. This can be helpful in directing the management for some patients.
How to do a biopsy
A punch biopsy is a simple, clean (not sterile) procedure with minimal risk of infection or bleeding. Inform the woman that the biopsy will leave a scar. Women today are very concerned with the cosmetic appearance of the vulva, and it is important that they know what to expect postbiopsy. Obtaining informed consent is advised. Local anesthesia using 1% lidocaine applied with a small-gauge needle will provide comfort for your patient during the biopsy.
Using a punch is straightforward (Figure 4). A biopsy need not be deep to obtain useful clinical information. A punch size between four and six millimeters will provide sufficient tissue for pathology. The procedure involves the following steps:
- Stabilize the skin with the thumb and forefinger, and stretch slightly in a direction perpendicular to the skin tension lines.
- Hold the punch perpendicular to the surface, and rotate into the skin with a firm, constant pressure until the desired depth has been reached.
- Do not remove the punch to check your progress, as this will result in a ragged wound and a shredded biopsy sample.
- Once you have reached the desired depth, remove the punch, and apply downward finger pressure at the sides of the wound to pop up the core.
- Grasp the specimen with forceps and cut it off at the base.3,4
Another approach is to use a fine-toothed forceps and fine scissors. Inject the local anesthesia, grasp the abnormal tissue with the pickups, and then cut off the lesion at the base.
After the biopsy sample has been obtained, apply direct pressure to the wound. Hemostasis with silver nitrate sticks or Monsel solution is adequate. Suturing is not normally necessary when a Keyes punch or fine-toothed forceps is used, as long as the biopsy was not performed too deeply. The site will heal by secondary intention.
Instruct the woman to keep the biopsy site clean. Rinsing the area after voiding or moving the bowels is helpful. An ice pack or nonsteroidal anti-inflammatory medication can be used, if needed, for local discomfort.
Documentation of the biopsy is necessary and should include the reason for biopsy and a description of the procedure, including skin preparation, type of local anesthetic, and size of Keyes punch. Specify the location of the biopsy, the disposition of the specimen, and the follow-up care for the patient. Schedule an appointment to review the pathology results and inspect the biopsy site.
Adequate communication with the pathologist is crucial. Take the time to complete the pathology request form carefully, so that it includes a brief clinical history, visual description of the lesion or abnormality, and your suspicions regarding the diagnosis. The more information you are able to give the pathologist, the more focused the results will be. If you have the option, request a dermatopathologist or a pathologist with an interest in skin disease.
Unfortunately, many dermatoses have nonspecific histopathology, so clinical judgment and skills need to guide your treatment/management. Be aware that if you just keep treating and treating, but the symptoms are not resolving, the best approach is to stop and reevaluate. If you are fortunate and have a vulvar specialist in your area, refer the patient for evaluation and management.
Susan Hoffstetter, PhD, WHNP, FAANP, is an associate professor in the Department of Obstetrics, Gyneology and Women’s Health Services, Division of Urogynecology, Saint Louis University School of Medicine, St. Louis, Mo., and a fellow in the International Society for the Study of Vulvovaginal Disease.
- Wilkinson EJ, Stone IK. Atlas of Vulvar Disease. Philadelphia, Pa.: Lippincott Williams & Wilkins; 2008.
- Fisher GO. The commonest causes of symptomatic vulvar disease: a dermatologist’s perspective. Australas J Dermatol. 1996;37:12-18.
- Grekin RC. Simple dermatological surgical procedures. Res Staff Phys. 1989;35:61-67.
- Dinehart SM, Hanke CW, Geronemus RG. Dermatologic Surgery for Medical Students. Schaumburg, Ill.: Association of Academic Dermatologic Surgeons; 1993.