Nodular melanoma: 5 questions, answered

Nodular melanoma is a type of skin cancer that can mimic benign conditions, including blood blisters and acne. It’s also one of the more invasive skin cancers since it mostly grows beneath the skin, where it can’t be seen.

To learn more about nodular melanoma, as well as how it's diagnosed and treated, we spoke with dermatologist Kelly Nelson, M.D.

What is nodular melanoma?

It’s a subtype of melanoma that makes up 15% to 30% of all new melanoma cases each year. It’s the second-most common type of melanoma. Only superficial spreading melanoma is more common. 

What does nodular melanoma look like? Is it the same thing as polypoid melanoma?

Nodular melanomas can look like pimples, moles, blood blisters, insect bites and other common skin blemishes. That’s why people often mistake them initially for things that have nothing to do with cancer.

But the word “nodular” is not really a reference to this disease’s appearance to the naked eye. It’s based on the disease’s pathology and growth pattern, or the way it looks under a microscope.

That being said, nodular melanomas can sometimes look a little like polyps, or little balls of skin hanging by a stalk. That’s pretty unusual, though. Normally, nodular melanomas are fairly symmetrical, with papules that are higher than the surrounding skin. They tend to be pink, brown, blue or black.

How is nodular melanoma diagnosed?

Nodular melanoma tends to catch people’s attention because it grows quickly. Sometimes, people feel like something isn’t looking right. But nodular melanoma doesn’t really follow the rules. So, it doesn’t always reflect the ABCDE guide we use to identify melanoma. Those are the traits that help people spot skin cancer more easily, like irregular borders or multiple colors. 

Other melanomas tend to grow outward along the skin before they invade the skin. Nodular melanoma is unique in that it always has some degree of tissue invasion beneath the skin. Though this type of melanoma can have a thicker appearance than others, much like an iceberg, it can mostly still be hidden below the surface.

How is nodular melanoma treated?

Nodular melanoma is treated very similarly to other melanomas.  

If we catch it early enough, surgery might be all that’s needed. But nodular melanoma tends to be pretty invasive, so additional treatment is often necessary, even in the earlier stages.

When that happens, we look for genetic mutations and other markers to see if a patient might benefit from targeted therapy or immunotherapy. After that, we explore options for clinical trials. 

What’s the one thing you want people to know about nodular melanoma? 

If something is growing rapidly and doesn’t look like the rest of what’s on your skin, please see a dermatologist. Rapid growth is the most helpful clue for diagnosing nodular melanoma at an early stage, when it’s easiest to treat.

Request an appointment at MD Anderson online or by calling 1-877-632-6789.