Version May 2024
INTRODUCTION — A wide variety of lesions occurs on the vulva. Some of the disorders causing these lesions are limited to the vulva, while others also involve skin or mucocutaneous membranes elsewhere on the body. This topic provides a morphology-based classification system that can help clinicians with the differential diagnosis of these lesions after performing a history and physical examination. This classification system is also useful for guiding the choice of diagnostic tests and procedures.
This topic will focus on the differential diagnosis of pigmented vulvar lesions, including black, brown, and blue lesions. Discussion of red, yellow, erosive and ulcerative, and white lesions are presented in related content.
●(See "Vulvar lesions: Differential diagnosis of red lesions".)
●(See "Vulvar lesions: Differential diagnosis of yellow, skin-colored, and edematous lesions".)
●(See "Vulvar lesions: Differential diagnosis of vesicles, bullae, erosions, and ulcers".)
●(See "Vulvar lesions: Differential diagnosis of white lesions".)
The pertinent history, physical examination, and diagnostic tests and procedures used to evaluate patients with vulvar lesions are described separately (see "Vulvar lesions: Diagnostic evaluation"). Treatment is also discussed separately in topic reviews on these disorders.
In this topic, when discussing study results, we will use the terms "woman/en" or "patient(s)" as they are used in the studies presented. However, we encourage the reader to consider the specific counseling and treatment needs of transgender and gender-expansive individuals.
MORPHOLOGIC DEFINITIONS FOR MUCOCUTANEOUS VULVAR LESIONS — Mucocutaneous vulvar lesions can be classified using the morphologic definitions described in the table (table 1).
DIAGNOSTIC EVALUATION
Practical tips — Based on the authors' experience, clinicians should be aware of the following points when evaluating dermatologic lesions of the vulva:
●Alternate appearance of vulvar lesions – Many skin conditions may appear differently on the vulva than on other parts of the skin as the vulva is so moist and the area is commonly subject to friction.
●Concomitant conditions – Concomitant conditions to consider with vulvar lesions include infections, other dermatoses, and neoplasia/cancer. For example, irritant contact dermatitis from the use of caustic soaps or overwashing is commonly seen in individuals with vulvar lichen sclerosus.
●Impact of topical therapies – Vulvar conditions may be significantly altered by the use of topical treatments. The authors ask patients about use of prescription, over-the-counter, compounded, and alternative topical preparations.
●Role of biopsy – Be prepared to perform a biopsy, especially if a vulvar lesion is atypical, bleeding, the patient is immunocompromised, the lesion is not responding to appropriate treatment, or there is concern for a premalignant or malignant condition [1]. For any lesions with variable or irregular areas, more than one biopsy may be needed. At times, the biopsy results can be inconclusive. If there are ever concerns or questions about the biopsy report, it is important to speak with the pathologist. Sending a clinical photograph to the pathologist can also aid the diagnosis.
●Consider possibility of systemic disease – Vulvar lesions can represent diseases that commonly present on the vulva (eg, herpes simplex virus) or systemic diseases that manifest in multiple sites including the vulva (eg, psoriasis). Providers are encouraged to ask patients with vulvar lesions about generalized symptoms and presence of lesions or skin changes on other body parts.
●Specialist referral – Patients whose symptoms do not respond, or worsen, despite usual treatment should be referred to a gynecologist, dermatologist, family medicine physician, or other health care providers who specialize in vulvar skin disorders.
How to use this topic — After a history, physical examination, and morphologic classification (table 1) have been performed, the information in this topic can be used to begin a differential diagnosis of the lesion. Diagnostic entities are listed for each morphologic classification and often listed under more than one morphologic classification since many lesions have more than one presentation (morphologic type, color). The complete description of the diagnostic entity is provided only once; for morphologic variants, the entity is noted and linked to its descriptive section.
This topic is an overview of pigmented dermatologic lesions of the vulva. Detailed text specific to each type of vulvar lesion is available separately, and links are provided throughout the text where available. Brief summaries of pertinent history, physical examination, and diagnostic tests and procedures are provided in this topic. Discussions of the presentation, evaluation, and diagnosis of vulvar lesions are described in detail separately.
●(See "Vulvar lesions: Diagnostic evaluation".)
●(See "Approach to the clinical dermatologic diagnosis".)
●(See "Skin biopsy techniques".)
COMMON ETIOLOGIES — The differential diagnosis of common causes of pigmented vulvar lesions is reviewed here (table 2) [2,3]. Biopsies may be required to confirm the diagnosis and/or exclude precancerous or malignant lesions. While all of these are common vulvar findings, the relative frequency of each may vary based on the patient population and type of clinical practice (gynecology, internal medicine, or dermatology).
Physiologic hyperpigmentation — Physiologic hyperpigmentation presents as asymptomatic, symmetric, flat, smooth, brown or brown-black patches on the labia majora and outer edge of the labia minora. It is more prominent in women with naturally dark skin color. Endogenous or exogenous sex hormones may lead to further darkening. The diagnosis is clinical and can be differentiated from postinflammatory hyperpigmentation because the latter is not as symmetric and even in color. (See "Congenital and inherited hyperpigmentation disorders".)
Postinflammatory hyperpigmentation — Postinflammatory hyperpigmentation may arise at sites of previous inflammation from any cause, including trivial insults such as a scratch, contact dermatitis, or a burn. The color varies from light tan to gray, blue, brown, or black. The pigmentation is flat and usually smooth, but slight scale may be present when the preceding inflammation was related to an eczematous process. The site and pattern will depend on the preceding inflammation. Postinflammatory hyperpigmentation resulting from lichen sclerosus typically appears as reticulated or patchy pigmented macules or regular patches along the peripheral edges of the vestibule or perineum (picture 1 and picture 2 and picture 3). Much less frequently these changes are seen in lichen planus.
A history of a prior inflammatory process or trauma will help to make the diagnosis. When the pattern is black or irregular, vulvar melanosis (lentiginosis) and melanoma must be considered. Several biopsies may need to be taken to make a definitive diagnosis and exclude malignancy. (See "Postinflammatory hyperpigmentation".)
Squamous intraepithelial lesions — Pigmentation is noted at times with vulvar squamous intraepithelial lesions (SIL), both low-grade SIL (LSIL) and high-grade SIL (HSIL).
●LSIL, including genital warts/human papillomavirus (HPV) effect, can present as skin-colored (table 3), white (table 4 and table 5), and/or red lesions (table 6 and table 7), but tan and brown hues may also be present.
●HSIL of the vulva is in the differential diagnosis of red (table 6), white (table 4 and table 5), and skin-colored lesions (table 3). However, they may be brown, gray, or black as the result of retained melanin granules in the thickened epithelium [4].
Differentiated vulvar intraepithelial neoplasia is often white in color. It usually is not pigmented.
A detailed discussion of vulvar SIL, including terminology, presentation, and treatment, is presented separately. (See "Vulvar squamous intraepithelial lesions (vulvar intraepithelial neoplasia)".)
A history of the terminology of these conditions is noted in the table (table 8).
Discussions specific to the presentation of vulvar SIL by color and morphology include:
●(See "Vulvar lesions: Differential diagnosis of yellow, skin-colored, and edematous lesions".)
Melanocytic nevi — Melanocytic nevi are common; 90 percent of nevi are the typical, benign type, presenting as symmetric, tan, or brown macules (junctional nevi) or papules (compound or intradermal nevi). The edges are sharply marginated, the color is homogenous, and most are less than 1 cm in diameter. Slight variation in color and outline is normal. They do not change in appearance over time. They are not symptomatic unless rubbed or irritated. They can be congenital or acquired.
●(See "Congenital melanocytic nevi".)
●(See "Acquired melanocytic nevi (moles)".)
These nevi are differentiated from melanoma by their symmetry, sharp border, homogenous color, uniform pigmentation, and small size (5 mm or less) [4]. They are differentiated from other pigmented lesions, such as seborrheic keratoses and HPV infections, by their smooth surface. Intradermal nevi are usually skin colored or only lightly pigmented. Nevi and, rarely, malignant melanomas can occur within the lesions of lichen sclerosus. Any questionable lesion should have a complete narrow excision or adequate biopsy.
●(See "Approach to the clinical dermatologic diagnosis".)
●(See "Skin biopsy techniques".)
Seborrheic keratoses — Seborrheic keratoses are small, benign, warty growths that occur anywhere on the body, but most commonly on the torso. When they occur in the anogenital area, they are restricted to nonmucosal, keratinizing skin. They typically develop after 35 to 40 years of age. The lesions are sharply marginated, tan, brown, or black papules with a warty, stuck-on appearance. Size is variable from 3 mm to over 2 cm, and the surface is elevated 2 to 10 mm above the surrounding normal skin surface. The surface scale can be scraped off with resulting pinpoint bleeding. On high magnification, there may be minute pits or milia-like keratin inclusions.
When seborrheic keratoses occur on the vulva, differentiation from HSIL of the vulva can be difficult. HPV lesions are usually small and multiple, whereas seborrheic keratoses are often solitary on the vulva, but there may be a large number elsewhere on the skin. Other pigmented lesions that can mimic vulvar seborrheic keratoses include basal cell carcinoma, dysplastic nevi, and melanoma. A biopsy is diagnostic. (See "Overview of benign lesions of the skin", section on 'Seborrheic keratosis'.)
Angiokeratomas — The papules of angiokeratomas are in the differential diagnosis of red papules and nodules (table 7), but they are often blue, violaceous, or even black. (See "Vulvar lesions: Differential diagnosis of red lesions", section on 'Angiomas'.)
Skin tags (acrochordons) — Skin tags (acrochordons or fibroepithelial polyps) are common, benign, soft, skin-colored, tan, or brown papules with short, thin stalks that are 1 to 3 mm. They occur on keratinized skin as single lesions or in groups on the inguinal folds. They are more commonly found, and more numerous in number, in obese women. When traumatized, they can be blue, purpuric, or black. Swelling may be present.
A fibroepitheliomatous polyp is a larger, solitary, skin-colored or brown lesion with a long, narrow stalk and broad tip. Differentiating these from pedunculated nevi may not be possible, except with biopsy. (See "Overview of benign lesions of the skin", section on 'Acrochordon (skin tag)'.)
LESS COMMON ETIOLOGIES — The differential diagnosis of less common causes of pigmented vulvar lesions are reviewed here (table 2) [2,3]. With the possible exception of varicosities, most will require a biopsy to confirm these diagnoses.
Lentiginosis/vulvar melanosis — Lentigines are asymptomatic flat, tan, brown, or black pigmented macules 2 to 8 mm in diameter. The lesions can be small but are often large, up to 2 cm in diameter. These lesions may be poorly demarcated, irregular in outline, and asymmetric in shape (often quite angular in shape). They are found mostly on the labia minora. They are typically seen in women in their 40s, which is younger than women with vulvar melanoma. (See "Benign pigmented skin lesions other than melanocytic nevi (moles)", section on 'Lentigo'.)
Vulvar melanosis, a benign condition, presents as a large, asymptomatic, hyperpigmented patch. The color is dark and is usually deep brown, or black. Vulvar melanosis accounts for 60 to 70 percent of all vulvar pigmented lesions [5]. The lesions may be poorly demarcated, irregular in outline, and asymmetric in shape. Vulvar melanosis develops in adult women and is most often located along the edges of the labia minora and the vulvar trigone, usually on the modified mucous membranes bilaterally. It may develop within lesions of lichen sclerosus. Vulvar melanosis tends to occur in younger women, whereas vulvar melanoma tends to occur in older women. The differential diagnosis includes postinflammatory hyperpigmentation, high-grade squamous intraepithelial lesions of the vulva, dysplastic nevi, and melanoma [6]. Several biopsies may be needed for diagnosis.
Lichen planus lesions — Lichen planus presents in classic, hypertrophic, and erosive forms and is in the differential diagnosis of red patches and plaques (table 6), white patches and plaques (table 5), and vulvar erosions (table 9) [7]. Lichen planus pigmentosus is a rare pattern of lichen planus seen mostly in darker skinned patients. It is a papulosquamous, pigmented eruption of papules forming varying sized plaques with irregular edges (picture 4) [8]. The color can be blue-gray to brown. Classically, it involves the skin folds in the groin, under the breasts, and in the axillae. It should be differentiated with a skin biopsy from postinflammatory hyperpigmentation, intertrigo, psoriasis, and fixed drug eruption.
●(See "Vulvar lichen planus".)
Atypical melanocytic nevus — Atypical nevi are found mainly on the perigenital skin. Individuals and family members with a history of many nevi with atypical patterns are referred to as familial atypical mole melanoma (FAMM) syndrome. (See "Atypical (dysplastic) nevi", section on 'Terminology and historical background'.)
Atypical nevi usually occur in older children and young women. The pigmented macules are smooth surfaced, >6 mm in diameter, with one or more atypical features, such as asymmetry, nonsharp margins, larger size, and variable pigmentation within the lesion. As the differential diagnosis includes malignant melanoma, an excisional biopsy is recommended. (See "Atypical (dysplastic) nevi".)
Melanomas — Vulvar melanomas are the second most common type of cancer of the vulva, after squamous cell carcinoma. Melanomas represent approximately 5 to 10 percent of all vulvar neoplasms [9]. They are more common in Caucasians and predominantly seen in women in their late 60s. Lesions suspicious for melanoma are often characterized by the ABCDEs. They are asymmetric (A); have an irregular or scalloped border (B); often black in color (C) or variegate with shades of red, white, or blue; may have a diameter (D) greater than 6 mm; and are evolving (E). Early signs include change in size, shape, and color of a lesion. On rare occasions, melanomas of the vulva can lack pigmentation [10]. Usually, melanomas are asymptomatic early in their course; however, pruritus may be an early symptom. Late signs and symptoms include bleeding, ulceration, pain, and tenderness. It is important to always biopsy any suspicious lesion. The unique molecular features of vulvar melanomas (as well as vaginal melanomas) render this disease a distinct subtype of melanoma [11]. Detailed discussion of melanoma can be found separately. (See "Melanoma: Clinical features and diagnosis".)
Varicosities — Varicose veins on the vulva are often seen in pregnant patients (picture 5). In most cases, they can be diagnosed on clinical examination [12]. They can be isolated or in groups. The small ones are moderately dark red or black, and the larger ones tend to be blue in color. Compression with a glass slide results in lesion disappearance, confirming the diagnosis. (See "Vulvovaginal varicosities and pelvic congestion syndrome".)
RARE DISEASES — These rare pigmented vulvar lesions typically require a biopsy or additional testing to confirm the diagnosis (table 2) [2,3].
●Pigmented basal cell carcinomas – The lesions of pigmented basal cell carcinomas generally occur on the labia majora in older women as solitary, usually skin-colored to pink and sometimes tan-to-brown papules, small plaques, or nodules. Sometimes, the surface is eroded or ulcerated. (See "Basal cell carcinoma: Epidemiology, pathogenesis, clinical features, and diagnosis".)
●Papillary hidradenomas – Papillary hidradenomas (mammary-like gland adenomas) are rare, benign, smooth-surfaced, soft-to-firm, 0.5 to 1.0 cm, translucent, skin-colored (picture 6), pink-red, or occasionally dark lesions on the vulva [13]. In a study of 52 clinical photographs of histologically confirmed papillary hidradenomas, commonly affected areas included the interlabial sulcus, skin adjacent to the labia, or the perineum [14]. Although previously considered apocrine tumors, papillary hidradenomas are now considered adenomas of mammary-like anogenital glands based on histologic findings. (See "Cutaneous adnexal tumors", section on 'Hidradenoma papilliferum'.)
●Acanthosis nigricans – Acanthosis nigricans is a rare vulvar condition affecting those with obesity (picture 7), thyroid disease, and, occasionally, metabolic syndrome. It presents as brown areas in the body folds, especially around the neck and in the axillae, but also in the crural folds. The surface is thickened and velvety, which gives the skin a dirty appearance. A biopsy will confirm the clinical diagnosis. (See "Acanthosis nigricans".)
SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Vulvar dermatitis".)
SUMMARY AND RECOMMENDATIONS
●Initial evaluation – For individuals with vulvar lesions, evaluation begins with a history, physical examination, and morphologic classification of the lesion (table 1), which allows formation of differential diagnosis. (See 'Morphologic definitions for mucocutaneous vulvar lesions' above.)
●Clinical points – Based on the authors' experience, clinicians should be aware of alternate appearances of vulvar lesions, concomitant conditions, topic therapies, role of biopsy, and possibility of systemic disease when evaluating dermatologic lesions of the vulva (see 'Practical tips' above):
•Patients whose symptoms do not respond, or worsen, despite usual treatment should be referred to a gynecologist, dermatologist, family medicine physician, or other health care providers who specialize in vulvar skin disorders.
●Differential diagnosis of pigmented vulvar lesions – The differential diagnosis of pigmented (black, brown, blue) vulvar lesions is presented in the table (table 2).
•Common etiologies include physiologic hyperpigmentation, postinflammatory hyperpigmentation, squamous intraepithelial lesions, melanocytic nevi, seborrheic keratoses, angiokeratomas, and skin tags (acrochordons). These diagnoses are often suggested by patient history and physical examination, but biopsy may be required for diagnosis and/or exclusion of malignancy. (See 'Common etiologies' above.)
•Less common etiologies include lentiginosis or vulvar melanosis, lichen planus, atypical melanocytic nevus, melanoma, and varicosity. With the possible exception of vulvar varicosities, biopsy is generally necessary for these diagnoses.
•Rare etiologies include pigmented basal cell carcinoma, papillary hidradenomas, and acanthosis nigricans. Biopsy is indicated to confirm the diagnosis and exclude malignancy.
ACKNOWLEDGMENT — The UpToDate editorial staff acknowledges Drs. T Minsue Chen, Aileen Langston, and Peter Lynch, who contributed to earlier versions of this topic review.
آیا می خواهید مدیلیب را به صفحه اصلی خود اضافه کنید؟
