Acanthosis nigricans (overview) L83

Author: Prof. Dr. med. Peter Altmeyer

All authors of this article

Last updated on: 16.12.2022

Dieser Artikel auf Deutsch


acanthosis nigricans; Black usury skin; dystrophia papillaris pigmentosa

This section has been translated automatically.

Janovsky, 1890; Politzer & Unna, 1890

This section has been translated automatically.

Clinical descriptive term for gray-brown, papillomatous-hyperkeratotic, mostly asymptomatic, polyetiologic, extensive growths of the skin, which typically occur intertriginously, more rarely additionally in acral expression (nose, ears, palmoplantar skin, also orally). Basically, it is a uniform, "reaction cutanée" in which the skin responds to various endogenous "growth" stimuli with nonspecific proliferation.

Acanthosis nigricans can be:

  • idiopathic
  • reactive in obese individuals
  • associated with endocrinological diseases or pregnancy (carefully exclude gestational diabetes)
  • medicinal
  • as a symptom of genetic defects
  • paraneoplastic (then often called "acanthosis nigricans maligna") in association with adenocarcinomas

occur in the context of adenocarcinomas.

This section has been translated automatically.

A distinction is made between:

This section has been translated automatically.

The pathogenesis depends on the different forms of the disease. An activation of growth factors is assumed, e.g. by formation and activation of growth factor receptors(epidermal growth factor receptor, insulin-like growth factor receptor and fibroblast growth factor receptor (FGFR)) with mitogenic and anti-apoptotic effects on keratinocytes. It is likely that in acanthosis nigricans there is rarely activation of a single growth factor (see Growth Factors below) but rather orchestration of multiple factors.

Drug-induced acanthosis nigricans results from interactions of certain drugs with lipid metabolism.

This section has been translated automatically.

Occurring in all age groups. Men and women fall ill about equally often.

This section has been translated automatically.

In principle, any area of the body can be affected. However, intertrigines, in particular armpits, lateral neck and neck areas, inguinal and genitoanal region are preferentially affected. Less frequently affected are eyelids, nasal entrance, elbows, popliteal or umbilical region. Involvement of palmae, plantae, oral mucosa and tongue is mainly observed in paraneoplastic acanthosis nigricans. In obese women with hyperandrogenism (e.g. in PCOS) without diabetes mellitus, the most frequent localization is the vulvar region.

Clinical features
This section has been translated automatically.

Mostly symmetrical development of initially yellow-brown to black hyperpigmentation, later area-like, velvety to verrucous enhancement of the skin texture, indistinctly demarcated from the surroundings. Possibly development of warty hyperkeratoses, which according to the current status are not seen as an independent clinical picture, but are partial symptoms of acanthosis nigricans, mostly acanthosis nigricans maligna. The growths may protrude in a cockscomb-like groin. The most severe changes are seen in the centers of the growths and in the intertriginous areas(ptychotropism).

On the mucosa rather rarely pronounced; here formation of planar, leukoplakic and rarely hyperpigmented areas. More rare is the development of cutis verticis gyrata.

The different forms do not differ clinically, but the paraneoplastic variant is often more extensive and clinically more pronounced. Furthermore, in the paraneoplastic variant, in addition to the classic intertriginous accentuated appearance, hyperkeratosis of the palmae and plantae as well as the flexor sides of the fingers and toes with pachydermodactyly may occur. In most cases there are no subjective complaints; in the malignant form itching may well occur.

This section has been translated automatically.

Papillomatosis and hyperkeratosis, slight mostly irregular acanthosis, basal hyperpigmentation, partially pseudohorn cysts. No significant inflammatory infiltrate in the dermis. Discrete parakeratosis with papillomatosis and epithelial hyperplasia on the mucosa, typically without proliferation of melanocytes in the epithelium. The "malignant" and "benign" forms of acanthosis nigricans do not differ histologically.

This section has been translated automatically.

Clinical picture and typical localization (the neck is often affected in early stages) are diagnostically groundbreaking.

General therapy
This section has been translated automatically.

Symptomatically in cooperation with the endocrinologist for the treatment of a possible underlying disease. Consistent hygiene of the intertrigines. In the obesity-associated form (Addison's disease, pseudoacanthosis nigricans), the skin changes usually regress when body weight is normalised. In addition, consistent hygiene of the intertriginous areas, washing with syndets.

Notice! The exclusion of malignoma is obligatory for all forms of acanthosis nigricans!

External therapy
This section has been translated automatically.

Mainly symptomatic therapy. Local therapy with covering, possibly zinc-containing powder or creams for dehydration (e.g. R294, R025 ). If necessary, keratolytic external therapy with creams containing salicylic acid(e.g. R216 ) or urea(e.g. R102 or basodexan); if necessary, low doses of vitamin A acid (e.g. R256 or Cordes VAS, Airol cream).

Internal therapy
This section has been translated automatically.

Therapy trials with acitretin (neotigason) or isotretinoin (e.g. isotretinoin-ratiopharm; acne normin) in low dosages have been described. In case of itching use antihistamines if necessary.

Operative therapie
This section has been translated automatically.

In the case of papillomatous growths, electrocaustic ablation can be attempted as a palliative measure, but this is usually only temporarily effective, as the skin changes can quickly reappear postoperatively.

This section has been translated automatically.

Malignant form

Benign forms


in addition to the typical localizations, frequent involvement of palmae, plantae, oral mucosa, tongue and eyelids

in overweight women with hyperandrogenemia often vulva area


mostly extensive involvement, partly generalized

less extensive affection


in addition to the classic appearance, hyperkeratosis may occur, especially on palmae and plantae as well as flexor sides of fingers and toes with pachydermatoglyphy ("tripe palms")

mucous membrane involvement

more frequently

more rarely

Subjective complaints

localized or generalized itching; in mucosal papillomatosis, pain and possibly dysphagia may occur

usually none

Associated symptoms

Malignancy of the internal organs, usually gastric carcinoma. Optionally, other paraneoplastic syndromes such as Leser-Trélat sign, hypertrichosis lanuginosa, pemphigus, palmoplantar keratoses or "tripe palms" may exist.

Diabetes mellitus, insulin resistance, obesity, hyperhidrosis, fibroma pendulans, hyperandrogenemia


acute onset and rapid spread, variable course, often fading after rehabilitation of the underlying malignancy with flare-up in case of metastasis

often improvement with weight reduction or regulation of the endocrinological disorder

This section has been translated automatically.

Unfortunately, the language rules are inconsistent in Acanthosis nigricans. Some authors define Acathosis nigricans - here called Acanthosis nigricans maligna - as originally described strictly and 100% as a paraneoplastic syndrome. The much more frequent benign variant - here called acanthosis nigricans benigna - is called pseudoacanthosis nigricans. There is no clearly discernible trend in the international literature. There are still no clinically proven morphological distinguishing features between these two groups. In this respect the clinical picture is to be considered as a uniform skin reaction to different endogenous proliferation factors. Helpful for the assumption of a paraneoplastic etiology is the exclusion of obesity and hormonal stimuli as well as the advanced age of the (tumor) patients.

This section has been translated automatically.

  1. Ceylan C, Alper S, Kilinc I. (2002) Reader's Trelat sign. Int J Dermatol 41: 687-688
  2. Janovsky V (1890) Acanthosis nigricans. In: Unna PG et al (Ed.) International Atlas of Rare Skin Diseases. Volume 11, Voss, Leipzig
  3. Lenzner U et al (1998) Acanthosis nigricans maligna. Case description and literature review. Dermatologist 49: 41-47
  4. Mellor-Pita S, Yebra-Bango M, Alfaro-Martinez J, Suarez E (2002) Acanthosis nigricans: a new manifestation of insulin resistance in patients receiving treatment with protease inhibitors. Clin Infect Dis 34: 716-717
  5. Pollitzer S (1890) Acanthosis nigricans. In: Unna PG et al (Ed.) International Atlas of Rare Skin Diseases. Volume 11, Voss, Leipzig
  6. Pollitzer S (1891) Acanthosis nigricans. In: Unna PG et al (eds.) International Atlas of Rare Skin Diseases. Lewis, London, pp. 1-3
  7. Schroeder B, Ding X, Pfaff-Amesse T (2002) From HAIR-AN to eternity. J Pediatr Adolesc Gynecol 15: 235-240
  8. Schwartz RA (1994) Acanthosis nigricans. J Am Acad Dermatol 31: 1-22
  9. Stulberg DL et al (2003) Common hyperpigmentation disorders in adults: Part II. Melanoma, seborrheic keratosis, acanthosis nigricans, melasma, diabetic dermopathy, tinea versicolor, and postinflammatory hyperpigmentation. On Fam Physician 68: 1963-1968
  10. Torley D, Bellus GA, Munro CS (2002) Genes, growth factors and acanthosis nigricans. British Journal of Dermatology 147: 1096-1101
  11. Yamazaki H et al (2003) Acanthosis nigricans is a reliable cutaneous marker of insulin resistance in obese Japanese children. Pediatric Int 45: 701-705


Please ask your physician for a reliable diagnosis. This website is only meant as a reference.


Last updated on: 16.12.2022