Skin Lesions: Everything You Need to Know

Medically Reviewed By Raechele Cochran Gathers, MD
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A skin lesion is any change in the usual character of the skin. It may occur on any part of the body and cover a tiny or large area. A primary skin lesion refers to the initial change in the skin, such as the development of a blister or lump. Secondary skin lesions occur due to changes in the initial skin lesion. Skin lesions include solid lumps, liquid filled blisters, raised areas of scaly skin, and skin tags. When there is a widespread eruption of lesions, this is known as a rash.

A skin lesion may appear as a result of a wide range of causes, such as a scrape from an injury to a more serious underlying medical condition. The patterns, shapes, and colors of skin lesions can help determine the cause.

Read on to learn more about skin lesions, including the different types of lesions and how doctors treat them.

What is a skin lesion?

There is a hand with skin lesions.
Anna Malgina/Stocksy United

A skin lesion is a bump, lump, or sore on the skin. Most skin lesions are benign, and they are not usually problematic. However, some lesions can be a symptom of a more serious condition, such as skin cancer.

There are two categories of skin lesions: primary skin lesions and secondary skin lesions.

Primary skin lesions

A primary skin lesion is an initial change to the skin. This could be a bruise following a fall, a mole or skin tag, or a lump that might indicate a more serious condition, such as skin cancer.

Some examples of primary skin lesions include:

  • Bulla: A bulla is a large, liquid filled blister measuring more than 1 centimeter (cm) in diameter.
  • Macule: A macule is a flat area of discolored skin.
  • Nodule: A nodule is a solid growth or lump up to 2 cm in diameter. It is primarily located in the deepest layers of the skin, and it is usually circumscribed, meaning that it has an outer edge.
  • Papule: A papule is a solid growth or lump up to 1 cm in diameter. Papules can be singular or multiple, and they can vary in shape, such as being either pointed or rounded.
  • Plaque: A plaque is an elevated patch of skin over 1 cm in diameter. Plaques can vary in shape and may occur as a result of multiple papules. Some cases of plaque may have well-defined borders.
  • Pustule: A pustule is a lesion filled with pus. Pustules are white or yellow, and they are not always infected.
  • Vesicle: A vesicle is a small blister up to 1 cm in diameter. Vesicles contain liquid, and they may be singular or multiple.

Secondary skin lesions

A secondary skin lesion occurs due to changes in the primary lesion. This can happen as a result of natural changes in the lesion, because of the individual manipulating or disturbing it, or due to the treatment of the initial lesion or a related condition.

Examples of secondary skin lesions include:

  • Atrophy: Atrophy occurs when the skin in the affected area shrinks and becomes paper thin, with wrinkles and visible vessels.
  • Crust: Crust is a result of dried fluid. It can be made up of blood, serum, or pus.
  • Erosion: An erosion is a sore that occurs due to the partial or superficial breakdown of the skin.
  • Fissure: Fissures are linear breaks in the skin’s surface. They are due to excessively dry skin.
  • Scale: A scale occurs as a result of the excess shedding or accumulating of the outer layer of the skin. This happens because of exfoliation and the atypical production of a protein called keratin.
  • Scar: A scar appears following an injury. It happens when normal tissue is replaced by connective tissue at the site of the skin injury.
  • Ulcer: A skin ulcer is an open sore on the skin. Ulcers can heal with scarring.

What is a benign skin lesion?

A benign skin lesion is a growth that is noncancerous. Anybody of any age can develop a benign skin lesion.

What is a malignant skin lesion?

A malignant skin lesion generally indicates skin cancer. This includes melanoma and non-melanoma skin cancer.

Around 1 in 5 people in the United States will develop skin cancer by the age of 70 years.

It is important to contact your doctor as soon as you notice any new or changing skin lesions, as early diagnosis plus treatment may help increase your likelihood of survival.

Melanoma skin lesions

Some examples of melanoma skin lesions include:

  • Superficial spreading melanoma: This is more common among people with pale skin and freckles. It typically grows outward. However, if superficial spreading melanoma grows downward, it can spread to other parts of the body.
  • Nodular melanoma: This is a fast developing melanoma that can quickly grow into deeper layers of the skin if it is not removed. It typically appears as a changing lump that might be black or red. It most commonly grows on the head, neck, chest, or back, and it can bleed or ooze.
  • Lentigo maligna melanoma: This commonly affects older adults who have spent a lot of time outside. It develops slowly over a number of years and tends to appear in areas that get the most sun exposure, such as the face. Lentigo maligna melanomas look like a larger and darker freckle, and they gradually get bigger. They may also change shape as they grow.
  • Acral lentiginous melanoma: This is a rare type of melanoma that typically grows on the palms of the hands and soles of the feet. It may also develop around a nail. Acral lentiginous melanomas are more common among people with dark skin, but they can develop in people with any skin color.
  • Amelanotic melanoma: This has little or no color. Occasionally, it may be pink or red, with light brown or gray edges.

The average age for a melanoma diagnosis is 65 years. However, the condition can also affect people who are younger than 30 years.

It is important to contact a doctor as soon as you notice a new or changing skin lesion that you cannot explain. Early diagnosis and treatment of localized melanoma skin cancer can increase the survival rate.

Learn more about melanoma here.

Non-melanoma skin lesions

Non-melanoma skin cancer develops slowly in the upper layers of the skin. It typically begins as a lump or discolored patch on the skin that persists for a few weeks before progressing over the course of months or years.

The lesion is typically a firm lump that may turn into an ulcer. Cancerous patches tend to be flat and scaly, but they can also be smooth. Non-melanoma skin cancer tends to develop on areas of the skin that are typically exposed to the sun, such as the face, shoulders, upper chest, hands, and ears.

Learn more about common sites for skin cancer here.

What causes skin lesions?

Skin lesions have a wide variety of possible causes. Some may occur due to injury, while others may appear as a result of an underlying condition that requires medical attention.

Some causes of skin lesions include:

  • acne, with lesions appearing due to a combination of inflammation, clogged pores, an increase in oily secretions, and increased Propionibacterium acnes bacteria
  • folliculitis, which can occur due to inflammation of the hair follicles and the presence of Staphylococcus aureus bacteria
  • fragile skin, which may result in the appearance of bruising
  • xerosis, or dry skin, which typically causes rough patches of skin and sometimes rashes
  • dermatitis, which can cause itchy, scaly skin and rashes
  • injuries, such as inflamed and raised skin lesions as a result of mechanical injury
  • insect bites, which can result in lumps or blistering
  • extreme cold, which can cause frostbite, resulting in blistering and damage to the top layer of the skin
  • sunburn, which can result in blisters and precancerous lesions in the future
  • allergic reactions, which can cause raised, itchy rashes known as hives
  • bacterial skin infections, such as impetigo and cellulitis, which can result in sores and blisters
  • viral infections, such as chickenpox and measles, which can produce spots and rashes
  • diabetes, with symptoms including blisters, wounds, sores, bumps, skin tags, and scaly patches of skin
  • skin cancer, which can result in a lump for non-melanoma skin cancer or a range of lumps and growths for melanoma skin cancer

Skin lesions may accompany other symptoms, which will vary depending on the underlying disease, disorder, or condition. Symptoms that frequently affect the skin may also involve other areas of the body.

Symptoms that may occur alongside skin lesions include:

Contact your doctor if you experience any of these symptoms alongside a skin lesion that you cannot explain. They will be able to carry out tests to determine the underlying cause.

When to contact a doctor

Contact your doctor if you notice any changes to an existing skin lesion. For example, an existing mole may begin to change in shape, color, or size.

If you notice a new skin lesion that you cannot explain, contact your doctor for advice — particularly if it is sore, painful, or accompanied by any other symptoms.

Diagnosing skin lesions

To diagnose the underlying cause of the skin lesion, your doctor will ask you a series of questions. These questions will depend on the type of skin lesion you have, but they might include:

  • When did you first notice the lesion?
  • Do you have any other skin lesions?
  • Do you have any other symptoms?
  • Does the lesion itch or burn?
  • Does the lesion have a discharge, such as pus?
  • Has the lesion changed in size, shape, or color?
  • Have you had similar lesions before?
  • Does anything relieve or worsen your symptoms?
  • Did you start any new medications or try any new types of food before you noticed the lesion?

A sample of the lesion may be required for testing in a laboratory. A dermatologist may carry out a procedure such as a punch biopsy, wherein they punch a small hole into the skin to remove a sample of the lesion for testing.

Treatments for skin lesions

Depending on the type of skin lesion you have, it may be possible to treat the condition and remove the lesion.

For example, you may wish to have a benign lesion removed if it is painful. Also, your doctor may recommend surgically removing a malignant skin lesion to reduce or prevent the spread of the condition.

Some examples of treatments for skin lesions include:

  • Excision of the lesion: During an excision, a surgeon will cut away the lesion to remove it. They will then suture, or close up, the wound and apply a dressing while it heals.
  • Shave biopsy: During a shave biopsy, a surgeon will shave off the skin lesion using a scalpel blade. Your doctor may recommend this technique for skin tags, warts, and scaly skin lesions.
  • Curettage: During curettage, a surgeon will scrape off the lesion using a sharp spoon-like instrument called a curette. This option may be suitable for warts, scaly skin, cysts, and skin bumps.
  • Mohs micrographic surgery: Your doctor may recommend Mohs surgery for a skin cancer lesion. A surgeon will use a local anesthetic to anesthetize the area, and they will take layers of tissue until they have completely removed the cancer.
  • Cryotherapy: Cryotherapy procedures use the extremely cold substance liquid nitrogen to freeze away skin lesions. This option may be suitable for benign lesions and precancerous scaly skin.
  • Dermabrasion: During dermabrasion, your doctor will exfoliate the skin lesion. This is a minimally invasive procedure that may take place in your doctor’s office.
  • Laser/light therapy: Your dermatologist can carry out laser/light therapy, which is a noninvasive approach to repairing damaged skin. During the procedure, the dermatologist will treat the affected area with a laser.

Complications of skin lesions

Depending on the cause of your skin lesion and how you approach it, it may lead to certain complications. For example, if you pick at the lesion or do not treat it, it may develop into a more serious condition.

Skin surgery to remove lesions may also result in complications. It is important for you to follow the treatment or aftercare plan that your doctor or surgeon recommends. This will help reduce the risk of the following complications:

  • infections
  • bleeding
  • scarring
  • changes in skin color
  • nerve damage
  • swelling

Contact your doctor or dermatologist if you experience any reactions or complications following skin lesion surgery.


When there is a visible change to the appearance of the skin, it is known as a skin lesion. This can include a blister following an injury, scaly patches from fragile or frail skin, or lumps from an underlying medical condition.

Many skin lesions are benign, which means that they are harmless. However, if a skin lesion begins to change shape, size, or color unexpectedly, it could mean that it is malignant. This tends to indicate a serious condition, such as skin cancer.

Following diagnosis, it may be possible to remove a skin lesion. Examples of surgical options to remove skin lesions include cutting them away, scraping away the damaged skin, freezing off the skin lesion, and undergoing laser therapy.

Contact a doctor if you notice any changes in an existing skin lesion or if you see a new skin lesion that you cannot explain.

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Medical Reviewer: Raechele Cochran Gathers, MD
Last Review Date: 2022 Mar 30
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