Hyperkeratosis: A Common Skin Condition
The term “hyperkeratosis” refers to a group of skin conditions characterized by thickening or hardening of the skin. The condition may be inherited, acquired, or congenital (congenital means present from birth). There are two main types of hyperkeriaesis: epidermal and dermal.
Epidermolysis bullosa (EBC) is a genetic disorder where the body’s immune system attacks healthy skin cells on the face, hands, feet, legs and other parts of the body. EBC is caused by mutations in one of three genes: EBV1, EBV2 or BRCA1. People with this disease have a higher risk of developing certain cancers. The most common type of EBC is called idiopathic EBC. Other types include:
Dermatofibrosarcoma (DFS): DFS is a rare cancer that affects the hair follicles in the scalp and upper back. It usually occurs in men between ages 15 and 30 years old. It may also cause bone tumors.
Keratoacanthoma (KA): KA is a type of skin cancer that resembles a cyst at first. It begins as a red, plaque-like bump on the skin which then fills with fluid and can develop a central spike (a small hair). Most of these growths develop in areas covered by hair or where the skin has been injured.
The cause of KA is unknown.
While hyperkeratosis may be a sign of an underlying health condition, it’s also a common disorder by itself. It usually does not cause other symptoms (medical problems) in most people.
Acral Keratosis Pictures
What are the different types of hyperkeratosis?
Within the two major categories of hyperkeratosis (epidermal and dermal), there are several sub-types:
 Common acquired epidermal hyperkeratoses include:
[1.1] Actinic keratosis (AK)
These rough, scaly patches that look like ‘corns’ or ‘calluses’ develop in areas of the skin that are repeatedly exposed to the sun. They most commonly appear on the face, ears, neck and bald heads, but can appear anywhere. AKs are not dangerous but they may be an indicator of skin damage that could lead to skin cancer and should be treated by a physician.
[1.2] Seborrheic keratosis (SK)
Seborrheic keratosis are common, benign growths that usually develop in adults age 20 or older. They can appear anywhere on the body but particularly on the trunk, especially in skin folds or areas repeatedly exposed to the sun. SKs do not cause problems but they may be an indicator of an increased risk of skin cancer.
[1.3] Lentigo (or “liver spots”)
Lentigo (or liver spots, or age spots) are flat, brown spots that commonly develop in elderly people. They are more common in people with light complexions. Lentigines are caused by exposure to the sun over a long period of time.
They do not typically cause problems but they may be an indicator of skin damage that could lead to skin cancer and should be treated by a physician.
Mucinosis is a condition in which skin lesions develop due to the formation of abnormal amounts of mucin (a slippery, substance secreted by epithelial cells) in the skin. It may be caused by prolonged exposure to heat, infection, and certain medications. Mucinosis does not typically cause problems but it may be an indicator of skin damage that could lead to skin cancer and should be treated by a physician.
[1.5] Reticulated pigmented epithelioma (RPE)
Reticulated pigmented epithelioma is a rare type of skin cancer with distinctive tumor-like, purple or brown lesions that develop in the skin. RPE is more likely to occur in individuals who have had significant sun exposure over many years. It does not typically cause problems but it may be an indicator of skin damage that could lead to skin cancer and should be treated by a physician.
Reticuloid is a type of skin cancer that develops in the top layers of the skin. It can appear as a wavy, net-like pattern under the top layer of the skin. The color of reticuloid lesions can vary from light yellow or brown to dark brown or black.
Reticuloid does not typically cause problems but it may be an indicator of skin damage that could lead to skin cancer and should be treated by a physician.
[1.7] Skin tags
Skin tags are small, benign growths that commonly form where skin rubs against other skin. They most commonly form in skin folds or under the arms. They are soft to the touch and may be brown, black, or tan.
They are not usually a sign of a skin problem and do not typically cause problems but they may be an indicator of skin damage that could lead to skin cancer and should be treated by a physician.
[1.8] Telangiectatic nevi
Telangiectatic nevi are common, benign moles that have telangectasias (dilated blood vessels). They are a cluster of small, red, purple or brown moles most commonly found on the trunk. Telangectasias are larger than the pores of the skin and visible to the naked eye.
Telangectasias may bleed and scab easier than normal moles do; they do not typically cause problems but they may be an indicator of skin damage that could lead to skin cancer and should be treated by a physician.
[1.9] Skin cancer
Skin cancer is a condition in which skin cells divide and grow into malignant tumors. There are three main types of skin cancer: basal cell carcinoma, squamous cell carcinoma, and melanoma. All three types of skin cancer can be treated if detected early but left untreated all three types of cancer may metastasize (spread) to other parts of the body causing serious health complications.
Here at the Centers for Disease and Control (CDC), we work to promote healthy habits, preventative medicine, and good-health practices. Skin cancer, though the least deadly of all cancers, is still a very real threat. There are multiple types of skin cancer, all of which develop in the top layers of the skin.
The most common types of skin cancer are listed below:
[2.1] Basal Cell Carcinoma
Basal cell carcinomas (BCC) are a very common type of skin cancer that develops in the basal cells, which are found at the base of the outer layers of the skin. They typically appear as a raised lump or wart-like spot on the skin. Most BCCs are pink or flesh-colored but they can also appear dark brown or black.
If you discover a new growth on your skin, especially one that is discolored, it is a good idea to have it checked by a physician (American Cancer Society, 2009).
[2.2] Squamous Cell Carcinoma
Squamous cell carcinomas (SCC) develop from the epidermis’s squamous cells. They generally arise in older people who spent a lot of time in the sun during their younger years. They are most common on the face and areas that have sustained a lot of sun damage.
SCCs can develop into large growths and in some cases can become cancerous (American Cancer Society, 2009).
Melanomas are a very dangerous type of skin cancer that can become malignant if left untreated. They develop from pigment-producing cells called melanocytes and they tend to occur in younger people. Most melanomas start as a new dark spot on the skin but in some cases, they can develop from a preexisting mole.
It is extremely important that you have any new or changed moles examined by a physician (American Cancer Society, 2009).
There are several ways to lower your risk of developing skin cancer:
? Try to avoid intense, unprotected sun exposure and always use sunscreen with an SPF of 15 or higher.
? Wear protective clothing, such as a wide-brimmed hat and UV-treated sunglasses (American Cancer Society, 2009).
? If you have fair skin that easily sunburns, it is especially important for you to avoid the sun between 10 AM – 4 PM, when the sun’s rays are the strongest. Also try to spend as little time outdoors as possible during this time (American Cancer Society, 2009).
? Avoid tanning salons. UV radiation is not good for your skin no matter how old you are and tanning salons are known to significantly increase your risk of developing skin cancer (American Cancer Society, 2009).
? Examine your skin on a regular basis. It is recommended that you look for any new or unusual moles or spots on your body once a month. If you find anything suspicious, have it checked out by a physician right away (American Cancer Society, 2009).
? If you smoke, quit. Tobacco use is a major risk factor for developing all types of skin cancer (American Cancer Society, 2009).
? Avoid direct exposure to woodstoves, fireplaces, or other sources of direct heat. Infrared radiation is carcinogenic (American Cancer Society, 2009).
The purpose of this project is to create a display that informs the public about skin cancer and how it is contracted. The National Institutes of Health and the American Academy of Dermatology offer a wealth of information about skin cancer. I have taken their facts and presented them in an attention-grabbing and non-biased way.
The display board will be divided into six sections: 1) What is skin cancer? 2) Who Is at Risk? 3) What are the Symptoms? 4) How Is it Diagnosed? 5) How Is It Treated? 6) What is the Prognosis?
These sections will contain relevant information about skin cancer, such as its causes, the types of it, who is at risk, how to recognize it, how it is treated and its survival rate. I will use tables and graphs to make the information more organized and easier to read. The tables and graphs will be created in Microsoft Word and then transfered onto the display board using magnets. Each table and graph will be labeled and explained underneath it.
The board will be displayed in the main entrance of the school for one week. During this time, an observation sheet will be placed next to the display board so that passersby can write down any questions they have about the display and then take the sheet up to their classroom to ask their teacher. After a week, the display board will be taken down and hopefully someone in the school will have written down some good questions.
Sources & references used in this article:
Histopathologic concept of epidermolytic hyperkeratosis by AB Ackerman – Archives of Dermatology, 1970 – jamanetwork.com
Clinical heterogeneity in epidermolytic hyperkeratosis by JJ DiGiovanna, SJ Bale – Archives of dermatology, 1994 – jamanetwork.com
Corns and calluses resulting from mechanical hyperkeratosis by DB Freeman – American family physician, 2002 – aafp.org