Acrochordon

4/11/2009 · Kategori: Dermatology

Acrochordon

Author: Robert A Schwartz, MD, MPH, Professor and Head, Dermatology, Professor of Pathology, Pediatrics, Medicine, and Preventive Medicine and Community Health, UMDNJ-New Jersey Medical School
Coauthor(s): Agnieszka Terlikowska, MD, Staff Physician, Department of Dermatology, Medical University of Warsaw, Poland; Wanda M Patterson, MD, Department of Dermatology, UMDNJ-New Jersey Medical School

Introduction

Background

An acrochordon is a small, soft, common, benign, usually pedunculated neoplasm that is found particularly in persons who are obese. It is usually skin colored or hyperpigmented, and it may appear as surface nodules or papillomas on healthy skin. Most acrochordons vary in size from 2-5 mm in diameter, although larger acrochordons up to 5 cm in diameter are sometimes evident. The most frequent localizations are the neck and the axillae, but any skin fold, including the groin, may be affected.

Birt-Hogg-Dube (BHD) syndrome is a rare autosomal dominant genodermatosis characterized by skin tumors, including multiple fibrofolliculomas, trichodiscomas, and acrochordons.¹ These patients tend to develop renal and colonic carcinomas.² The defective gene in BHD syndrome has been identified and is suspected of being a tumor suppressor gene. Several mutations of the BHD gene have been reported.³ All skin lesions in the syndrome may actually represent fibrofolliculomas cut in various planes of section.

Related eMedicine articles of possible interest include Premalignant Fibroepithelial Tumor (Pinkus Tumor), Benign Vulvar Lesions, and Skin, Benign Skin Lesions.

Pathophysiology

Previous theories have suggested that a localized paucity of elastic tissue may result in sessile or atrophic lesions. It is also thought that pendulous variations may be caused by losses of large confluent areas of elastin; however, a 1999 study of elastic tissue in fibroepithelial polyps (FEPs) showed no significant abnormalities.⁴

Frequency

International

Acrochordons have been reported to have an incidence of 46% in the general population.

Mortality/Morbidity

Acrochordons are benign tumors. On rare occasions, histologic examination of a clinically diagnosed FEP reveals a basal or squamous cell carcinoma. In a recent study, 5 of 1335 clinically diagnosed FEP specimens were malignant. Four were basal cell carcinomas, and one was a squamous cell carcinoma in situ. None of these specimens was submitted by a dermatologist. This study concluded that clinically diagnosed FEPs have a low probability of having malignant characteristics on histologic examination.

Sex

An equal prevalence of acrochordons exists in males and females.

Age

When present, acrochordons increase in frequency up through the fifth decade. As many as 59% of persons may have acrochordons by the time they are aged 70 years.

Clinical

History

Acrochordons are flesh-colored pedunculated lesions that tend to occur in areas of skin folds.

• A family history sometimes exists of acrochordons.
• These tumors are usually asymptomatic, and they do not become painful unless inflamed or irritated.
• Patients may complain of pruritus or discomfort when an acrochordon is snagged by jewelry or clothing.
• Acrochordons may occur at unusual sites of the body. A huge acrochordon has been described on the penis.⁵ A lymphedematous acrochordon of the glans penis unassociated with condom catheter use also has been described.⁶ An acrochordon may be associated with vulval itching without the symptom being the result of fungal infection.⁷
• Endoscopy may reveal FEPs arising in a ureter.⁸
• Multiple skin tags are often linked with type 2  diabetes mellitus and with obesity, prompting a study of 58 people with skin tags. It showed that people with skin tags had significantly higher serum cholesterol and lower density lipoprotein levels, but not serum leptin levels, when compared with a healthy control group lacking skin tags.⁹

Physical

• Skin tags may occur singly or multiply, and they are most often found in intertriginous areas (eg, axillae, neck, eyelids) (see Media File 1). They are also commonly located on the trunk, the groin, the abdomen, and the back.

• FEPs of the oral mucosa, anus, and vulvovaginal areas may be found.
• These lesions may be flesh colored or hyperpigmented.
• Three types of acrochordons are described.
  • Small, furrowed papules of approximately 1-2 mm in width and height, located mostly on the neck and the axillae
  • Single or multiple filiform lesions of approximately 2 mm in width and 5 mm in length occurring elsewhere on the body
  • Large, pedunculated tumor or nevoid, baglike, soft fibromas that occur on the lower part of the trunk
• Pedunculated lesions may become twisted, infarcted, and fall off spontaneously.

Causes

• Frequent irritation seems to be an important causative factor, especially in persons who are obese. An opinion also exists that acrochordons are simply the effect of skin aging, with many factors responsible for their development.
  • Hormone imbalances may facilitate the development of acrochordons (eg, high levels of estrogen and progesterone during pregnancy, high levels of growth hormone in acromegaly).
  • Epidermal growth factor (EGF) and alpha tissue growth factor (TGF) have also been implicated in the development of tumors such as these.
  • Whether any infective factors initiate acrochordon growth is still not clear.
• Human papillomavirus (HPV) types 6/11 DNA were found in a high percentage of skin tag biopsy samples obtained from 49 white patients (see Human Papillomavirus). According to the authors of the study, viral infection should be considered as a pathogenic cofactor.¹⁰
• Acrochordons associated with fibrofolliculomas and trichodiscomas have been described as components of BHD syndrome, an autosomal dominant disorder. They have been reported to accompany other neoplasms, especially tumors of the gastrointestinal tract and kidneys.
  • Neoplasms are suggested to produce and release growth factors that cause acrochordon growth into the circulation.
  • The results of a recent study refute the theory that an association of acrochordons and colonic polyps actually exists.
• An association with type 2 diabetes mellitus has been observed.^11,12
  • A study of 118 research subjects with acrochordon reported an incidence of 40.6% of either overt type 2 diabetes mellitus or impaired glucose tolerance.
  • Reports exist suggesting that the mechanism is through the effect of insulin and glucose starvation.¹³
  • The previous study showed no correlation between the location, size, color, or number of acrochordons with impairment of glucose tolerance.