In this article, we look at the symptoms, diagnosis, and treatment of some of the most common causes of bumps on the skin.
Common bumps on the skin
Image credit: Sand et al., Head & Face Medicine, 2010
One common type of bump that appears on the skin is a papule, which is a type of pimple. Unlike pustules, which are the type of pimple that have a yellowish, liquid blister of pus, papules are solid to the touch.
Both papules and pustules appear when the pores of the skin become so clogged with dead skin cells, oil, and bacteria that the walls of the pore break.
Papules can be treated with over-the-counter medicines. If these do not work, a doctor who specializes in skin known as a dermatologist can prescribe medications.
Skin tags are another common type of bump on the skin. The medical name for a skin tag is acrochordon. Skin tags are skin-colored growths that hang from the surface of the skin by a "stalk."
Skin tags are more common in older people, and often develop after weight gain or pregnancy. They usually appear in the skin folds of the neck, armpits, torso, chest, or genitals.
These bumps do not cause pain and are considered a cosmetic concern rather than a medical problem. They are not a form of skin cancer and cannot become cancerous.
Basal cell carcinoma
Some skin growths can be cancerous. The most common of these is basal cell carcinoma, which can look like pink growths, open sores, shiny bumps, or red patches.
More than 4 million cases of basal cell carcinoma are diagnosed every year in the United States.
Basal cell carcinoma is usually caused by intense sun exposure. It is extremely rare that the carcinoma spreads beyond the original tumor site, but it is important to have basal cell carcinoma treated. If left untreated, it may cause nerve and muscle injury.
The most serious type of skin cancer is melanoma. Melanoma can affect any area of the body - it can grow deeply into the skin and may also affect the lymph nodes and blood vessels.
In 2016, over 87,000 adults in the U.S. were diagnosed with melanoma. Despite accounting for about 1 percent of all skin cancers diagnosed in the U.S., melanoma is responsible for the majority of deaths from skin cancer.
Melanomas are often dark brown or black in appearance.
Skin cancers are usually caused by excessive sun exposure. Exposure to ultraviolet radiation - from any type of sun exposure - can also actinic keratosis.
Actinic keratosis can appear on areas of the body exposed to sun or an indoor tanning bed. These areas include:
- the face
- back of the hands
Actinic keratosis looks like crusty, scaly growths that sometimes resemble warts and are rough and sandpapery in texture.
Hemangiomas are a type of noncancerous tumor that can grow on the skin.
If someone has multiple hemangiomas on their skin, they are at increased risk for also having an internal hemangioma. Internal hemangiomas grow in the internal organs; most often, the liver.
A basal cell carcinoma may be caused by intense sun exposure.
Although it can be tempting to squeeze pimples, people should not squeeze papules as they do not have any pus inside of them, and squeezing can cause the skin to scar instead.
The best way to prevent papules is to follow good skin care. Wearing sunscreen may also help. As sun exposure can cause the skin to become inflamed, which can drive the development of papules.
To prevent getting actinic keratosis, basal cell carcinoma, melanoma, and other skin cancers, it is important to follow sun-safety habits. People should avoid direct sunlight for prolonged periods, especially between the hours of 10am and 4pm.
People are advised to apply 1 ounce of sunscreen with a sun protection factor (SPF) of 15 or higher to their entire body 30 minutes before going outside. Those who plan on being outside for a long time should use a broad spectrum sunscreen with an SPF of 30 or higher.
Tanning also increases risk for skin cancer, and people should never use ultraviolet tanning beds
When to see a doctor
Skin tags do not go away on their own. If someone has a skin tag that they want removed, they will need to see a doctor.
The removal process is quick and easy. Doctors can cut skin tags away with scissors or a sharp blade, and may use an electric cauterizing tool to prevent bleeding.
It is important to remember that skin tags do not normally cause medical problems and cannot become cancerous.
Doctors can normally diagnose skin tags easily by looking at them. However, if it is not obvious that a growth is a skin tag, a doctor may cut a portion of the growth away and send it to a laboratory to be tested. This is called a biopsy.
Basal cell carcinoma can only be diagnosed by a trained doctor. The appearance of the carcinoma can often resemble other skin conditions, such as psoriasis or eczema. The doctor will need to take a biopsy in order to diagnose basal cell carcinoma.
There are several different surgery options available for basal cell carcinoma. Radiation therapy and special light therapies are effective treatments. There are also some creams, gels, and solutions that can treat basal cell carcinoma.
Skin abnormalities that look black, change size or color, or bleed can be signs of melanoma, and so should be checked out by a doctor. New and unusual moles can also be a sign of melanoma, so it is important for these to be checked.
As with basal cell carcinoma, a biopsy will usually be taken to confirm whether or not a skin abnormality is melanoma. The usual treatment for melanoma is to surgically remove the tumor and some surrounding healthy tissue.
If untreated, actinic keratosis lesions can also rarely develop into skin cancer, so people should get these growths checked out by a doctor.