What is Clear Cell Acanthoma (Benign Skin Tumor Usually of the Legs)?
Clear cell acanthoma (CCA), sometimes referred to as “Degos acanthoma” or “acanthome cellules Claires of Degos and Civatte,” was first identified by researchers named Degos et al. in 1962. It’s a unique, harmless thin layer of cells or tumor with an unknown origin. Although they often appear on the lower limbs of the body, it’s possible for them to occur elsewhere like the torso, forearm, face, groin area, and even on and around the nipple, which is quite rare. Usually, only one of these tumors is found on a person, but on rare instances, a person can have more than one in different parts of the body.
These tumors typically show in middle-aged to older people as a painless, gradually growing, red or reddish-brown, dome-like bump. What’s unique about them is that they also have a crisp, wafer-like flake or ring around them. The good news is, because they are benign, meaning they’re not dangerous, people who have them can expect a good outcome. Doctors usually need to take a small sample of the skin, a process known as a biopsy, to properly diagnose it, but there are other ways it can be identified and removed too.
What Causes Clear Cell Acanthoma (Benign Skin Tumor Usually of the Legs)?
The exact cause of clear cell acanthoma, a specific type of skin condition, is still unknown. Some scientists think it’s a benign skin growth, while others believe it’s a type of skin inflammation that reacts to certain triggers. If considered a growth, there’s debate about whether it originates from the skin’s outermost layer, hair follicle, or sweat glands. Most professionals believe it’s a skin layer tumor, as initially suggested.
Some experts propose it might be a variant of another skin condition, seborrheic keratosis, where skin cells contain a lot of a substance called glycogen. Another theory is that this condition could be an inflammatory skin issue. This idea is backed up by studies showing the skin lesions in clear cell acanthoma have certain proteins called cytokeratins, often seen in other inflammatory skin conditions such as psoriasis.
Further support for this theory comes from cases where clear cell acanthomas have been found on existing psoriasis skin patches. Research has also found links between clear cell acanthomas and other conditions like persistent skin inflammation, varicose veins, viral infections, and insect bites.
Risk Factors and Frequency for Clear Cell Acanthoma (Benign Skin Tumor Usually of the Legs)
Clear cell acanthoma is a type of skin growth that can affect anyone, regardless of gender. Most of the time, it’s middle-aged individuals, especially those between 50 and 60 years old, who are most likely to develop it. However, it’s rare in children. This condition doesn’t favor any particular race or ethnicity either.
- Clear cell acanthoma can occur in both males and females equally.
- It is most common in middle-aged individuals, particularly between 50 and 60 years of age.
- Children are unlikely to develop the condition.
- There are no particular races or ethnic groups more affected by this skin condition.
Signs and Symptoms of Clear Cell Acanthoma (Benign Skin Tumor Usually of the Legs)
A clear cell acanthoma is a kind of skin growth that usually appears as a solitary, reddish or reddish-brown, dome-shaped bump or lump. It often has a flaky “collar” around the edge, though not always. The surface of the growth could be crusted or moist and might even bleed if it’s slightly injured. These growths slowly get bigger over several years and can be anywhere from a few millimeters to 2 centimeters in size. Some people describe clear cell acanthomas as looking like they’re “stuck on.”
The growths are most frequently found on the lower legs. They can also appear, though less commonly, on the trunk, forearms, face, groin area, nipples, scalp, and the red part of the lip. There are a variety of forms of clear cell acanthoma, including ones that are large, hanging, pigmented, erupting, atypical, and cystic.
Testing for Clear Cell Acanthoma (Benign Skin Tumor Usually of the Legs)
Dermoscopy, a technique used to examine the skin, can be an important tool in helping diagnose a type of skin growth known as clear cell acanthoma. This method reveals a unique pattern that can assist doctors in identifying this condition.
Under the dermoscope, blood vessels appear as tiny pinpoint or glomerular shapes. They are arranged in a curved, net-like pattern that looks like a string of pearls, commonly referred to as a “pearl necklace” appearance. This pattern is different from other skin conditions that also show these pinpoint vessels, making clear cell acanthoma distinct.
In the end, while dermoscopy can be helpful, a definitive diagnosis is usually confirmed through a skin biopsy. This involves taking a small sample of the skin growth to be examined under a microscope.
Treatment Options for Clear Cell Acanthoma (Benign Skin Tumor Usually of the Legs)
When it comes to managing clear cell acanthomas, which can show up as skin growths, the preferred strategy usually involves completely removing them. There are several ways this can be done, and the choice depends on factors like the location of the growth, its size, and how many there are.
One common method is a procedure called ‘shave removal’ or ‘curettage’, which is often paired with electrofulguration – a form of treatment that uses heat produced by an electric current. There are other options as well, including cryotherapy (where extreme cold is used to kill abnormal cells), performing electrofulguration by itself, standard surgical removal, or using a type of laser known as a carbon dioxide laser.
If a patient has multiple growths, then treatments like cryotherapy or carbon dioxide laser might often be the best choices.
What else can Clear Cell Acanthoma (Benign Skin Tumor Usually of the Legs) be?
When a doctor is considering the diagnosis for clear cell acanthoma, they would also consider a range of other conditions with similar symptoms. These can include skin conditions such as:
- Pyogenic granuloma (a type of skin growth)
- Benign lichenoid keratosis (a harmless skin lesion)
- Inflamed seborrheic keratosis (a noncancerous skin growth)
- Eccrine poroma (a rare, benign sweat gland tumor)
- Basal cell carcinoma (a kind of skin cancer)
- Squamous cell carcinoma (another kind of skin cancer)
- Amelanotic melanoma (a type of skin cancer with no pigment)
- Psoriasis (a skin disorder causing red, itchy scaly patches)
Each of these potential diagnoses has its own appearance and traits. Clear cell acanthoma, in particular, has a unique pattern of blood vessels that can be seen when examined with a special skin microscope (dermoscopy). This allows doctors to distinguish it from the other conditions listed.
What to expect with Clear Cell Acanthoma (Benign Skin Tumor Usually of the Legs)
Clear cell acanthomas are generally harmless skin growths. They usually grow slowly over several years and can remain on the skin. There has only been one reported case noted by Garcia-Gavin et al., where the growths disappeared on their own. This happened in a patient who had multiple growths that vanished naturally, leaving behind skin darkening after inflammation.
Several case reports mention “atypical” clear cell acanthomas, but none of these became harmful or came back after treatment. Removing a clear cell acanthoma through different methods can entirely cure it.
Possible Complications When Diagnosed with Clear Cell Acanthoma (Benign Skin Tumor Usually of the Legs)
When all of a mole or spot is removed, there could be a few issues that arise. These include scarring, changes in skin color (either lighter or darker), and infection. These complications can vary based on the method used to remove the mole or spot. Patients need to be aware that scarring is a potential side effect of any method that involves removing tissue. Using a method called cryotherapy, which freezes the mole or spot, can lead to lighter skin patches. This is especially noticeable in people with darker skin, because the treatment destroys skin cells that produce color, known as melanocytes.
Preventing Clear Cell Acanthoma (Benign Skin Tumor Usually of the Legs)
When the diagnosis is clear, the doctor should reassure the patient that their condition is not harmful. However, it’s important to understand that the issue won’t just go away by itself. The patient should be informed about various ways to remove the problem, but they should also know that any method is likely to leave a scar. If the diagnosis isn’t certain, the doctor might suggest taking a sample of the problematic area, a procedure also known as a biopsy. This process, while helpful in making a diagnosis, may also cause a scar.
