If you have a wound or irritation on your skin that doesn't seem quite right or isn't healing as it should, chances are it might be some kind of lesion. But is the skin lesion cancerous or not? That's the important question. 

Lesions are defined as almost any type of change on an organ or tissue resulting from disease or injury – and as it so happens, the skin is the largest organ in your body. There are numerous types of lesions with different names, and they are categorized by whether or not they are cancerous. 

A dermatologist can check your skin for marks and determine whether you have a lesion that should be tested. He or she will remove the lesion and send it to the lab for testing. From there, the tests will determine whether the lesion is benign, malignant or has the possibility of becoming malignant. If it the legion is potentially malignant, it is referred to as a premalignant lesion. 

Lesions are often categorized by the pattern they might form, location, the person who first discovered or described them, or their size. There are bulls eye or target lesions named for their shape, coin lesions with round shadows that look like coins on an x-ray, gross lesions (large enough to be seen without magnifying), microscopic lesions, central lesions (of the brain or spinal cord), and more. 

Benign Skin Lesions 

Seborrheic keratosis

The most common type of skin tumor, seborrheic keratosis, is usually scaly and brown. Sometimes greasy, they vary in size and thickness and sometimes look as if they have been attached or stuck onto the skin. Seborrheic keratosis can show up anywhere on the skin except the palms, soles of feet or any mucous membranes. 

Usually, treatment includes removing the lesion, possibly with cryotherapy, or freezing. Sometimes the appearance of many lesions at once on the trunk or chest may be a sign of cancer. In many cases, they are usually benign. It's best to get a doctor's opinion. 

Dermatosis papulosa nigra

Dermatosis papulosa nigra are hyperkeratotic, hyperpigmented lesions, usually found on the face and neck. They are dark, slightly raised benign spots. Almost 50 percent of the black population has some degree of dermatosis papulosa nigra, and it tends to affects women more regularly than it does men. 

In most cases, they are not removed unless they become a nuisance and are itchy or irritated. 

Sebaceous hyperplasia

An enlargement of the sebaceous glands, sebaceous hyperplasia is characterized by a yellow or flesh-colored papule with a small dip in the center. They usually form on the faces of adult patients. Sebaceous hyperplasia is most common in men who have undergone organ transplants and often resemble cancerous lesions, but they are benign. 

Generally, they are removed by cutting, cryotherapy or laser therapy. 

Ephilides

Ephilides, or freckles, are another type of skin lesion. These are small, hyperpigmented spots on sun-exposed skin. They mostly affect people who are fair skinned. They aren't necessarily tumors, but over-pigmented spots of the skin. If you have a large numbers of freckles, it may indicate a greater risk of melanoma, so freckles should be monitored. 

Freckles themselves are not treated. Sometimes, people will try to bleach or lighten them for cosmetic reasons, but there is no medical reason for removing ephilides. 

Lentigines

Lentigines, commonly referred to as "liver spots," are darkened patches that resemble moles. They are usually brown or tan and tend to increase as we age. Generally, they show up on sun-exposed parts of the skin, and like freckles, a large number of them can signal a risk of skin cancer. These lesions themselves, however, are not harmful. 

Treatment for liver spots is mostly cosmetic. 

Nevus

A nevus, or mole, is a common benign lesion that is usually darker than the surrounding skin and is raised. There are many factors that contribute to the development of moles, such as race, age and sun exposure. Most moles are benign, but some can be atypical and should be checked by a doctor. See below for signs of atypical lesions. 

Other types of lesions

There are many other types of lesions that are benign. Skin tags, dermatofibroma (reddish brown spots found on extremities), cherry angiomas (red vascular growths), lipomas, cysts and milia, are all types of lesions that you may find on your skin. Only a dermatologist or qualified doctor can diagnose what type of lesion you have, so it's best to check anything suspicious with a professional. 

Malignant skin lesions 

The types of moles that you should worry about are melanomas or non-melanomas -- skin cancer. Skin cancer is the most common form of cancer. These two types of skin cancer vary in diagnosis and treatment, but it's important to know their signs and differences. 

Melanomas are the most dangerous form of skin cancer. They are rarer than non-melanomas but are far more problematic. Melanomas cause malignant tumors that can spread to different parts of the body. They begin in a part of the skin called the melanocyte, which creates melatonin, the skin's pigment. This is why they are often brown or black in color. Many times, melanomas can start on the back or chest in men and on the legs in women. It's important to note that people with darker skin have less risk of developing melanomas, but they still can get melanomas. 

Non-melanomas are the most common type of skin cancer. They include basal cell carcinomas and squamous cell carcinomas. There are other types of non-melanomas, but basal cell and squamous cell account for the most non-melanomas. Basal cell carcinomas comprise eight out of 10 cases of non-melanomas and usually show up in areas where there has been a lot of sun exposure. Squamous cell carcinoma accounts for about two in10 cases of non-melanoma and appears on sun-exposed skin, but it can be present in scars or chronic skin sores. 

Know your ABCDEs 

There are simple ways to spot potentially troublesome moles or lesions that could be cancerous. Knowing your ABCDEs -- asymmetry, border, color, diameter, evolving. 

Asymmetry is an unevenness of the mole. If you draw a line through the middle of the spot, it should be symmetrical, or the same on both sides. If it's not the same on both sides, the mole is asymmetrical and may be cancerous. 

Borders of a normal mole or freckle are usually even. The borders of an early melanoma tend to be crooked or scalloped. 

Color is often another indicator of trouble. Moles that show different shades can be cancerous. Cancerous lesions can be multiple shades of tan, brown or black. It's also common to find melanomas that have red or blue coloring to them. 

The diameter of a melanoma is usually larger than a pencil eraser. Sometimes when detected early, they can be smaller, but it's important to watch large moles or lesions closely because they may be cancerous. 

An evolving mole may be a sign of cancer. A mole that changes size, shape, color, elevation or another characteristic may be a cancerous mole. Additionally, other changes such as bleeding, itching or crusting are signs of trouble. 

If you see new growths or notice that skin lesions have changed, then it's important to see a dermatologist as soon as you can. Melanoma is a survivable cancer when caught in the early stages. When allowed to metastasize – in other words, spread to internal organs, the survival rate decreases dramatically. Reduce your risk by not exposing yourself to the sun and having a dermatologist check your skin annually.