Table of Contents
Definition / general | Epidemiology | Diagnosis | Case reports | Clinical images | Microscopic (histologic) images | Differential diagnosis | Additional referencesCite this page: Nagarajan P. Pigmented lesions. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/vulvapigmented.html. Accessed March 30th, 2023.
Definition / general
- This topic covers common nonmelamoma pigmented lesions of vulva
Epidemiology
- Very common, present in 10 - 12% of adult white women (Dermatol Clin 1992;10:361)
Diagnosis
- Dermoscopy is useful for distinguishing between various lesions (Br J Dermatol 2011;164:54)
Case reports
- 6 year old girl with acquired (idiopathic) intradermal nevus (Eur J Pediatr 2009;168:1405)
- 11 year old girl with Spitz nevus of genital mucosa (Indian J Dermatol Venereol Leprol 2009;75:167)
- 15 year old girl with cellular blue nevus of vulva mimicking Bartholin gland abscess (Arch Gynecol Obstet 2012;285:1009)
- 22 year old woman with angiokeratoma of clitoris with vulvar varicosity (J Obstet Gynaecol Res 2010;36:1249)
- 24 year old woman with melanocytic dysplasia and melanoma of vulva (Eur J Gynaecol Oncol 2002;23:323)
- 41 year old woman with Dowling-Degos disease on vulva (Ann Dermatol 2011;23:205)
- 78 year old woman with unusual pigmented basal cell carcinoma arising from vulva (Acta Dermatovenerol Alp Pannonica Adriat 2011;20:81)
- 87 year old woman with extensive pigmented vulvar basal cell carcinoma (Dermatol Online J 2011;17:8)
- Unilateral angiokeratoma of vulva (J Dermatol 2013;40:763)
- Pigmented seborrheic keratoses of vulva (Clin Exp Dermatol 2005;30:17)
Clinical images
Microscopic (histologic) images
Contributed by Priya Nagarajan, M.D., Ph.D.
Images hosted on other servers:
Differential diagnosis
- Acanthosis nigricans (Indian J Dermatol 2011;56:678, Fertil Steril 1993;59:583)
- Clinical presentation:
- Pigmented / brown velvety plaques
- Histologic features:
- Mild epidermal acanthosis, papillomatosis (usually with elongated, delicate papillae), hyperkeratosis, horn pseudocysts
- Mild increase in basal layer pigmentation
- Clinical presentation:
- Angiokeratoma (Eur J Gynaecol Oncol 2011;32:597, Acta Dermatovenerol Croat 2010;18:271)
- Clinical presentation:
- Dark papules and nodules
- Histologic features:
- Epidermal hyperkeratosis, acanthosis (often irregular) and low papillomatosis in close proximity to thin walled dilated blood vessels filled with red blood cells in papillary dermis
- Clinical presentation:
- Dowling-Degos disease (Ann Dermatol 2011;23:205)
- Clinical presentation:
- Multiple symmetric pigmented papules
- Histologic features:
- Elongation and prominent pigmentation of epidermal rete ridges
- No increase in melanocyte density
- Suprapapillary plate thinning, pigment incontinence and hyperkeratosis may be present
- Clinical presentation:
- Genital dysplastic nevi
- Clinical presentation:
- Irregular pigmented lesion, often on labia majora
- Histologic features:
- Features overlap with atypical genital nevi (J Cutan Pathol 2008;35:24, Am J Surg Pathol 2008;32:51)
- More lentiginous spread and elongation of rete ridges may be seen
- Lamellar eosinophilic fibroplasia of papillary dermis is present
- Variable amounts of lymphohistiocytic inflammatory infiltrate may be present
- Clinical presentation:
- Genital melanocytic nevi (Eur J Gynaecol Oncol 2002;23:323, J Cutan Pathol 2008;35:889, Dermatology 2010;221:55, Dermatol Online J 2010;16:9)
- May affect about 2% of women
- Any type of nevus can be seen in the vulva
- Clinical presentation:
- Irregular pigmented lesion up to 1 cm in size
- Lesions typically involve labia minora, labia majora or mucosal aspect of clitoris
- Histologic features:
- Some degree of architectural disorder is allowed in special sites such as vulva
- Nevi may be junctional or compound and may be asymmetrical
- Junctional component is composed frequently of lentiginous proliferation of melanocytes, which is often nested
- Nests may be large with retraction artifact and usually arise from the sides of rete ridges and may involve the suprapapillary plate
- Adnexal extension may be seen
- Dermal melanocytes mature with dermal descent
- Overlying epidermis may be hyperplastic
- Due to frequent irritation, features of trauma such as focal pagetoid spread of melanocytes, pigmented parakeratosis and transepidermal elimination of melanocytic nests may be seen
- Genital melanosis (J Reprod Med 1993;38:5, Am J Dermatopathol 1985;7:51)
- Clinical presentation:
- Variably extensive and slowly developing pigmentation
- Histologic features:
- Hyperpigmentation of basal keratinocytes
- Melanocyte density is usually normal or very mildly increased
- Pigment incontinence in superficial dermis may be present
- Clinical presentation:
- Lichen simplex chronicus (Dermatol Clin 2010;28:669)
- Clinical presentation:
- Dark, pigmented, thickened skin
- Histologic features:
- Epidermal acanthosis (may be slightly irregular), hyperkeratosis (often with presence of stratum lucidum), hypergranulosis
- Fibrosis or presence of thickened, vertically oriented collagen fibers in papillary dermis
- Superficial perivascular lymphohistiocytic infiltrate
- Pigment incontinence may be present
- Clinical presentation:
- Mucosal melanotic macules (J Am Acad Dermatol 2000;42:640, J Am Acad Dermatol 2014;70:e81)
- Clinical presentation:
- Dark asymmetrical macules
- Histologic features:
- Hyperpigmentation of basal keratinocytes
- Melanocyte density is usually normal or very mildly increased
- No nested or confluent proliferation of melanocytes
- Clinical presentation:
- Normal vulvar pigmentation
- When compared to the rest of the body, genital skin is usually more pigmented
- Histologically, it is common to see at least some amount of melanin pigmentation within the basal keratinocytes
- Therefore, it is important to know the baseline pigmentation of the patient, since the presence of basal keratinocytic pigmentation can be misleading, especially in small biopsies
- Pigmented basal cell carcinoma (Dermatol Online J 2011;17:8, Acta Dermatovenerol Alp Pannonica Adriat 2011;20:81)
- Pigmented condyloma acuminatum (J Dermatol 2014;41:337, J Dermatol 2012;39:860)
- Clinical presentation:
- Dark warty growths with fleshy or filiform appearance
- Often multiple
- Histologic features:
- Epidermal acanthosis with hyperkeratosis and at least focal parakeratosis, with an undulating surface
- Deep aspect of the lesion is fairly regular and sharply demarcated
- Superficial keratinocytes with perinuclear halo, hyperchromatic nuclei and irregular / wrinkled nuclear contours (koilocytes), consistent with human papilloma viral cytopathic effect
- Clinical presentation:
- Pigmented seborrheic keratosis (Clin Exp Dermatol 2005;30:17)
- Clinical presentation:
- Often multiple
- Dark, brown papules or nodules with a stuck on appearance
- Histologic features:
- Epidermal acanthosis, low papillomatosis, hyperkeratosis and horn pseudocysts
- Clinical presentation:
- Pigmented vulvar intraepithelial neoplasia / pigmented bowenoid papulosis (Gynecol Oncol 1980;10:201, An Bras Dermatol 2014;89:825, J Am Acad Dermatol 2010;62:597)
- Clinical presentation:
- Dark plaques, papules
- Histologic features:
- Usual type vulvar intraepithelial neoplasia (squamous cell carcinoma in situ or Bowen disease) with full thickness keratinocytic atypia
- Melanin pigment often in small dense clusters within the epithelium
- Pigment incontinence may be present
- Lichenoid lymphohistiocytic inflammatory infiltrate may be present
- Clinical presentation:
- Postinflammatory pigmentary alteration (Dermatol Ther 2010;23:449)
- Clinical presentation:
- Slowly increasing pigmentation which is often the result of an inflammatory condition
- Initiating inflammatory disease is frequently asymptomatic
- Histologic features:
- Prominent pigment incontinence with melanin lying free in the superficial dermis or more frequently, increased numbers of pigmented melanophages
- Clinical presentation:
Additional references