acanthoma

Acanthoma: A Benign Skin Lesion

Acanthoma, also known as clear cell acanthoma (CCA), is a type of benign skin lesion that typically affects older adults. It presents as a small, reddish bump on the skin, often with a sharp demarcation between the lesion and the surrounding skin.

Characteristics:

• Acanthoma is usually a single, painless papule or nodule
• It can be found on various parts of the body, including the trunk, arms, and legs
• The lesion is typically small in size, ranging from 1-3 cm in diameter
• It may have a reddish or brownish color, with a smooth surface

Types:

• Acantholytic acanthoma: a type of acanthoma that involves the breakdown of skin cells (acantholysis)
• Clear cell acanthoma: a type of acanthoma characterized by the presence of clear cells in the lesion
• Other types, such as epidermolytic and glycogenated acanthomas, may also exist

Causes and Treatment:

• The exact cause of acanthoma is unknown, but it is thought to be related to chronic trauma or sun exposure
• Acanthoma is generally a benign condition and does not require treatment unless it becomes symptomatic or causes cosmetic concerns
• In some cases, the lesion may be biopsied to rule out other skin malignancies

References:

• [4] Clear cell acanthoma (CCA) is an epidermal tumor composed of pale-staining, glycogenated keratinocytes with a sharp demarcation between the ...
• [9] Clear cell acanthoma is a benign epidermal tumor, typically of the leg, with acanthosis and accumulation of glycogen in keratinocytes ...
• [12] Acantholytic acanthoma is a single bump found on the trunk of the body. It usually occurs in older people and is typically painless.
• [13] Etiology of keratoacanthoma is unknown. Most experts consider these lesions to be well-differentiated squamous cell carcinomas with a tendency to involute..

Common Signs and Symptoms of Acanthoma

Acanthoma, also known as keratoacanthoma, presents with distinct physical characteristics that can be observed on the skin. The symptoms may vary depending on the type of acanthoma, but here are some common signs and symptoms:

• Volcano-like appearance: Acanthomas often appear as a small, red or skin-colored volcano with a distinctive crater at the top, containing keratin or dead skin cells [1].
• Rapid growth: These skin lesions can grow rapidly, usually within a few weeks, reaching a size of 1-2 centimeters in diameter [15].
• Single or multiple bumps: Acanthomas may appear as single or multiple red bumps on the skin, which can be firm to the touch [9][11].
• Painless: In most cases, acanthomas are painless and do not show any other signs or symptoms apart from their physical appearance [6].
• Hyperkeratosis: Thickening of the outer layer of the skin is a common symptom associated with acanthoma fissuratum [7].
• Fissuring: Cracks or splits in the skin may occur, which can bleed or become inflamed [7].

Types of Acanthomas

Different types of acanthomas have distinct symptoms. For example:

• Keratoacanthoma: Typically presents as a rapidly growing nodule on sun-exposed skin, with a central crater and scaly or crusted appearance [3][11].
• Acantholytic acanthoma: Usually occurs as a single papule or nodule on the trunk of older people, which is typically painless [10].

References

[1] - Context result 1 [3] - Context result 3 [6] - Context result 6 [7] - Context result 7 [9] - Context result 9 [10] - Context result 10 [11] - Context result 11 [15] - Context result 15

Diagnostic Tests for Acanthoma

Acanthoma, also known as clear cell acanthoma, can be diagnosed through various diagnostic tests. Here are some of the common methods used to diagnose this condition:

• Dermatoscopy: This is a non-invasive test that uses a special microscope to examine the skin lesion. Dermatoscopy can show a highly characteristic pattern of blood vessels in clear cell acanthoma, which can aid in diagnosis [4][5].
• Skin Biopsy: A skin biopsy involves taking a small sample of tissue from the affected area and examining it under a microscope. This is often the most definitive way to diagnose clear cell acanthoma, as it can show the characteristic accumulation of clear glycogen-containing cells in the epidermis [5][6].
• Physical Exam: A dermatologist will perform a physical exam to assess the size, shape, and color of the lesion. They may also use dermoscopy during the exam to aid in diagnosis [14].

Other Diagnostic Methods

While less common, other diagnostic methods include:

• Immunohistochemistry: This test can be used to confirm the diagnosis of clear cell acanthoma by examining the expression of certain proteins in the skin cells.
• Histopathological Examination: A histopathologist will examine the tissue sample taken from the biopsy to look for characteristic features of clear cell acanthoma.

References

[4] Dermoscopy is an excellent diagnostic test, since it shows a highly characteristic pattern. The test shows glomerular or punctiform vessels arranged in linear patterns, with a pearl necklace appearance [10].

[5] The diagnosis of the typical clear cell acanthoma is usually simple, especially through dermoscopy. Dermoscopic pattern of clear cell acanthoma as a necklace-like arranged capillaries was first time featured by Blumm in 2001 [9].

[6] Clear cell acanthoma shows a characteristic accumulation of clear glycogen-containing cells in the epidermis, which can be seen under a microscope during a skin biopsy [5].

Based on the provided context, it appears that there are various treatment options for acanthoma, including drug treatments.

Intralesional triamcinolone may be used to hasten resolution of the lesion [1]. This is a type of corticosteroid injection that can help reduce inflammation and promote healing. However, it's essential to note that this treatment is not always necessary, as acanthoma fissuratum will often resolve on its own if the source of skin irritation is removed [6].

Additionally, intralesional corticosteroid injection can improve symptoms [6]. This suggests that drug treatment may be beneficial in managing symptoms associated with acanthoma.

It's also worth noting that conservative measures aimed at reducing friction and pressure are often recommended as the first line of treatment for acanthoma fissuratum [9]. While this approach is more focused on lifestyle changes rather than direct drug treatment, it highlights the importance of addressing underlying causes of skin irritation in managing acanthoma.

In summary, while there are various treatment options available for acanthoma, intralesional triamcinolone and corticosteroid injections may be used to hasten resolution of the lesion or improve symptoms. However, conservative measures aimed at reducing friction and pressure should also be considered as a first line of treatment.

References: [1] S Ramroop · 2020 · Cited by 7 — Typical treatment involves removal of the cutaneous irritant. Intralesional triamcinolone may hasten resolution of the lesion, possibly through its potent anti‐ ... [6] Treatment is not required as acanthoma fissuratum will resolve if the cause of the irritation is removed. Intralesional corticosteroid injection can improve ... [9] Conservative Measures. The first line of treatment for acanthoma fissuratum involves conservative measures aimed at reducing friction and pressure. These may ...

Differential Diagnosis of Acanthoma

Acanthoma, a type of skin lesion, can be challenging to diagnose due to its varied clinical appearance and overlapping features with other conditions. The differential diagnosis for acanthoma includes:

• Basal cell carcinoma: A common skin cancer that can present as a small, shiny bump or nodule.
• Squamous cell carcinoma: Another type of skin cancer that can appear as a firm, red nodule or a flat, scaly patch.
• Seborrheic keratosis: A benign growth that can look like a brown spot or a raised patch on the skin.
• Pyogenic granuloma: A small, red bump that can bleed easily and is often mistaken for a skin cancer.
• Eccrine poroma: A rare type of skin tumor that can appear as a small, painless nodule.
• Lichenoid keratosis: A benign growth that can look like a small, scaly patch or a raised bump on the skin.

These conditions can be difficult to distinguish from acanthoma due to their similar clinical appearances. However, dermatoscopy and histopathological examination are essential tools for accurate diagnosis (7).

In some cases, the differential diagnosis may also include:

• Clear cell acanthoma: A rare type of skin tumor that can appear as a small, pinkish patch or nodule.
• Sebaceous carcinoma: A rare type of skin cancer that can present as a firm, yellowish nodule.

It's essential to note that the diagnosis of acanthoma is rarely made before a skin biopsy (6). However, dermatoscopy can be characteristic in some cases, showing lined vessels and a pinkish background (14).

References

• Haake DL, et al. Am J Dermatopathol. 2009 Jun;31(4):391-2.
• Nousari CH, et al. Am J Dermatopathol. 2009 Jun;31(4):393-5.
• PubMed Search: Acanthoma (9)