How Fast Does Skin Cancer Grow? What You Should Know

Skin cancer occurs when skin cells mutate and grow uncontrollably. The most common cause of skin cancer is cell damage from the sun’s ultraviolet (UV) rays. Skin cancer is common: About 1 in 5 people in the United States will develop it by age 70. 

How fast skin cancer grows depends on several factors, including the type of skin cancer. Checking your skin and raising any concerns to a healthcare provider can help you prevent or detect skin cancer before it spreads, making it easier to treat.

Skin cancer growth rate refers to how quickly the cancer cells multiply and spread throughout your body. Cancers that spread quickly tend to be more challenging to treat. 

Slow-Growing Skin Cancers

The two most common types of skin cancer are basal cell carcinoma and squamous cell carcinoma. These skin cancers tend to grow slowly.

Basal cell carcinoma: This cancer develops in basal cells found in the outermost layer of your skin, called the epidermis. About 8 in 10 cases of skin cancer in the United States are caused by basal cell carcinoma. The average growth rate for basal cell carcinoma is 0.7 millimeters per month, but this varies depending on the subtype and where the cancer develops.

Squamous cell carcinoma: This cancer develops in the flat outer cells of the epidermis and makes up about 2 in 10 cases of skin cancer in the U.S. Squamous cell carcinoma grows slightly faster than basal cell carcinoma but is still considered a slow-growing cancer.

Aggressive Skin Cancers

Other skin cancers tend to be more aggressive, meaning they grow more quickly. These include melanoma and a rare type called Merkel cell carcinoma.

Melanoma: This is a more aggressive form of skin cancer that develops in melanocytes, the skin cells that produce pigment to give skin its color. It’s much less common than basal and squamous cell carcinoma.

Melanoma can spread quickly, depending on the type and where it develops. The four subtypes of melanoma include:

• Superficial spreading melanoma: This type is less aggressive because it tends to spread outward on the skin instead of deeper into the body.
• Nodular melanoma: This type grows and spreads rapidly. 
• Lentigo maligna melanoma: This type is slow-growing and less aggressive than other types of melanoma. 
• Acral lentiginous melanoma: This cancer usually develops under your nails or on the soles of your feet, making it harder to detect before it grows.

It’s difficult to determine the exact growth rate of melanoma. Some types can grow quickly, while others may take years to develop. 

Merkel cell carcinoma: This is a rare and aggressive skin cancer. These cancer cells usually spread quickly, and treatment may be challenging. 

The growth rate of skin cancer varies depending on the cancer type, location, stage, and other factors. Older adults and people with lighter skin tones are at the highest risk of developing skin cancer. Factors that affect skin cancer growth rates include:

• Cancer type: The type of cancer affects how quickly it will grow. Basal and squamous cell carcinomas usually grow slowly, while melanoma grows quickly. Skin cancer subtypes tend to grow at different rates. 
• Genetics: Certain genetic mutations may cause skin cancer to be more aggressive and spread quickly. Healthcare providers may test your blood for biomarkers, which are molecules that give clues about affected genes. 
• Location: The location of skin cancer may affect its growth. Skin cancer on the scalp or in hard-to-see areas can grow undetected, leading to a delayed diagnosis.
• Sunburn history: A history of severe sunburns significantly increases skin cancer risk. Five or more sunburns in your lifetime double your risk of melanoma, a fast-growing cancer.
• Healthcare access: Skin cancer is often treatable when diagnosed in the early stages of the disease.

The key to early skin cancer detection and treatment is noticing changes in your skin. The earlier a new skin growth is identified, the sooner you can receive an accurate diagnosis and an appropriate treatment plan.

You can monitor your skin health with these tips:

• See a dermatologist (a doctor specializing in diagnosing and treating skin conditions) for a yearly skin check.
• Look at your skin carefully and take note of any moles, freckles, or other marks.
• Perform a skin self-exam by inspecting all areas of your skin. Use a mirror for hard-to-see areas.
• See a dermatologist if you notice a new skin growth or a changing area. 

To monitor your skin for signs of melanoma, use the ABCDE rule. This stands for:

• Asymmetry: The two sides of a mole look different
• Border: The edges are jagged or uneven 
• Color: The mole has different colors
• Diameter: The mole is larger than 6 millimeters across
• Evolving: The mole’s appearance changes

Most cases of skin cancer are due to skin damage from UV rays. You can be exposed to UV rays from the sun, indoor tanning beds, and sunlamps. Lower your risk of skin cancer by taking these precautions to avoid UV damage:

• Never use tanning beds.
• Wear sunscreen with a sun protection factor (SPF) of at least 30.
• Wear sunglasses when spending time outdoors.
• Wear a wide-brimmed hat to help protect your face.
• Cover your arms and legs with lightweight pants and long-sleeve shirts.
• Stay in the shade during the hottest times of day.

It’s important to see a healthcare provider if you have any concerns about your skin. If your primary healthcare provider suspects that you may have skin cancer, they will refer you to a dermatologist for testing and treatment.

It’s also important to see your provider if you develop a new skin lesion or sore that does not heal on its own. The sore may feel painful or itchy. See your provider right away if you notice that a mole is changing in color, shape, or size.

Skin cancer occurs when skin cells mutate and grow uncontrollably. There are several different types of skin cancer, and they grow at different rates.

Basal cell carcinoma is the most common type and tends to grow slowly. Squamous cell carcinoma is the second most common type and also usually grows slowly. Melanoma is less common than the other types, but much more aggressive and fast-growing.