WHAT IS A KERATOACANTHOMA?A keratoacanthoma is a spherical skin tumor that develops quickly and can grow to several centimeters. The word "tumor" sounds serious and malignant, but it is simply the Latin medical term for "a swelling." A tumor can therefore be malignant or benign. Opinions differ on whether a keratoacanthoma should be considered benign or malignant. Some consider a keratoacanthoma to be a benign tumor that closely resembles a squamous cell carcinoma (which is a malignant skin tumor), but is not. Others consider it a variant of squamous cell carcinoma, but a milder form, that does not behave malignantly (i.e., it does not grow deeply or spread throughout the body).
Despite its rapid growth, there is no need to worry if you are diagnosed with a keratoacanthoma. If the experts can't agree on whether it should be called benign or malignant, you already know it's not very dangerous. And there is an effective treatment: removing the keratoacanthoma. This is usually done with a simple technique: the lump is numbed, then scraped off the skin with a spoon-shaped instrument, and the base is briefly cauterized with electricity.
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kerato-acanthoma |
HOW DOES A KERATOACANTHOMA DEVELOP?Keratoacanthoma arises from hair follicle cells. Regarding the name, acanthoma refers to a swelling originating from the skin or parts of it (such as hair follicles). The suffix "kerato-" refers to the large amount of keratin (horny material) usually seen in the center of a keratoacanthoma. A keratoacanthoma develops when skin cells suddenly begin to divide and multiply much faster than normal. The exact cause is unknown. It is thought that DNA damage caused by sunlight plays a role. Keratoacanthomas primarily develop in areas frequently exposed to sunlight, such as the face, ears, arms, and hands, but they can also develop on the torso, in areas with little sun. Keratoacanthomas typically develop in older adults (60+).WHAT ARE THE PHENOMENA?Over the course of several weeks (rapidly growing), a round, skin-colored or pinkish-red tumor develops on the skin. The tumor can grow to a diameter of several centimeters. A characteristic feature is the presence of a central keratoacanthoma. The keratoacanthoma does not cause pain or itching, and does not bleed (unless scratched). A keratoacanthoma can develop anywhere on the skin, but is more commonly seen in sun-exposed areas, such as the face or hands. Sometimes multiple keratoacanthomas can develop simultaneously, or in quick succession. This is seen in patients with compromised immune systems (for example, patients with a donor kidney) and in certain hereditary diseases.
If left untreated, most keratoacanthomas disappear on their own over time (within a few months). The keratoacanthoma gradually shrinks. Sometimes it disintegrates or partially detaches. Eventually, it disappears completely, but after spontaneous healing, a scar remains. Usually it doesn't get that far, because they are removed by the dermatologist.
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keratoacanthoma |
keratoacanthoma |
HOW IS THE DIAGNOSIS MADE?The dermatologist can make the diagnosis based on the rapid growth and the external characteristics (spherical, lying on top of the skin, with a horn plug, painless). If necessary, the tissue is sent to the pathology laboratory for microscopic examination. However, it's not easy for the pathologist to distinguish between a keratoacanthoma and a mild variant of squamous cell carcinoma. The result is often: "keratoacanthoma, but squamous cell carcinoma cannot be completely ruled out." After which, the diagnosis is again left to the dermatologist's discretion.WHAT IS THE TREATMENT?The simplest treatment for a keratoacanthoma is scraping it off (curettage) under local anesthesia, followed by electrocautery of the base. The tissue of a keratoacanthoma is not very hard and lies largely on top of the skin. Therefore, it is relatively easy to scrape off. The base is then cauterized with an electrocoagulation device. This stops minor bleeding. The heat also destroys the innermost layer of cells in the keratoacanthoma, preventing regrowth. After this procedure, a superficial wound (sometimes a small dent) with a scab remains. This heals over a few weeks, leaving a tolerable scar. The other method is surgical removal: excision followed by suturing. Because keratoacanthomas can be very large, with a base of 2-3 centimeters, excision isn't always the most attractive or practical solution. This also depends on the location. For example, a large keratoacanthomas on the tip of the nose are not likely to be removed due to the damage this causes to the nose.WHAT ARE THE OUTLOOK?The outlook is good. If the keratoacanthoma is completely removed, it will not return. If a small piece remains, it can still be removed. Furthermore, keratoacanthomas are eventually eliminated by the body itself. |
