Mayo Clinic | American Hospital

Dermatofibrosarcoma protuberans (DFSP) is a rare type of skin cancer. It starts in connective tissue cells in the middle layer of the skin (dermis).

Dermatofibrosarcoma protuberans might look like a pimple or feel like a firm patch of skin at first. As it grows, lumps of tissue (protuberans) may form near the surface of the skin. This skin cancer often forms on the arms, legs and trunk.

Dermatofibrosarcoma protuberans grows slowly and rarely spreads beyond the skin.

Overview

Causes

The cause of dermatofibrosarcoma protuberans often isn't known.

This skin cancer happens when cells in the skin develop changes. The changes happen in the cells' chromosomes. Chromosomes are threadlike structures inside cells that contain DNA and proteins. The changes in the chromosomes cause the cells to make many more cells quickly. The cancer cells form a growth that starts underneath the skin and may push up to create a lump over time. Other lumps may appear as well.

Preparing for an appointment

Make an appointment with a doctor or other healthcare professional if you have any symptoms that worry you. If your health professional believes you may have skin cancer, that person may refer you to a specialist. Often this is a doctor who specializes in treating skin conditions, called a dermatologist.

Appointments can be short, and being prepared can help. Here's some information that may help you get ready.

What you can do

When you make the appointment, ask if there's anything you need to do in advance, such as fasting before having a specific test. Make a list of:

Your symptoms, including any that don't seem related to the reason for your appointment.
Key personal information, including major stresses, recent life changes and family medical history.
All medications, vitamins or other supplements you take, including the doses.
Questions to ask your healthcare professional.

Take a family member or friend along, if possible, to help you remember the information you're given.

For dermatofibrosarcoma protuberans, some basic questions to ask your health professional include:

Do I have cancer?
If the lump or lumps aren't cancerous, do I still need to have them removed?
Do I need more tests?
What are my treatment options?
What are the potential risks of these treatment options?
Do any of the treatments cure dermatofibrosarcoma protuberans?
Can I have a copy of my pathology report?
How much time can I take to consider my treatment options?
Are there brochures or other printed material that I can take with me? What websites do recommend?
What would happen if I chose not to have treatment?

Don't hesitate to ask other questions.

What to expect from your doctor

Your healthcare professional is likely to ask you several questions, such as:

When did your symptoms begin?
Have your symptoms been happening all the time or do they come and go?
How severe are your symptoms?
What, if anything, seems to improve your symptoms?
What, if anything, appears to worsen your symptoms?

Risk factors

Risk factors for dermatofibrosarcoma protuberans include:

Age. This cancer can happen at any age. But it happens most often in adults ages 20 to 50.
Race. This cancer happens more often in Black people than it does in people of other races.
Prior skin injury. People with skin that has been burned, treated with radiation or scarred from surgery may be more likely to have this cancer.
History of dermatofibrosarcoma protuberans. This cancer can come back locally after surgical removal.

There is no way to prevent dermatofibrosarcoma protuberans.

Diagnosis

Tests and procedures used to diagnose dermatofibrosarcoma protuberans include:

Skin exam. Your healthcare professional may inspect your skin to look for signs of skin cancer.
Skin biopsy. Your healthcare professional may remove a small amount of tissue for testing. Tests in the lab can see if cancer cells are present.
Imaging tests. Sometimes imaging tests, such as an MRI, are needed to see the extent of the cancer and to help with treatment planning.

Treatment

Dermatofibrosarcoma protuberans treatment typically involves surgery to remove the cancer. Other treatments may be used to kill cancer cells that might remain after surgery.

Treatment options may include:

Surgery to remove the cancer. Dermatofibrosarcoma protuberans tends to grow in a shape that's not regular. This makes the cancer hard to remove completely. Your healthcare professional may recommend a procedure to remove the cancer and some of the healthy tissue around it. This makes it more likely that all the cancer cells are removed.
Mohs surgery. Mohs surgery is a type of surgery that involves cutting away thin layers of cancer-containing skin until only cancer-free tissue is left. After each layer of skin is removed, it's examined for signs of cancer. The process keeps going until there are no signs of cancer. Mohs surgery may be helpful for treating larger cancers.
Radiation therapy. Radiation therapy uses powerful energy beams, such as X-rays and protons, to kill cancer cells. Your health professional may recommend radiation therapy if all the cancer couldn't be removed during surgery.
Targeted therapy. Targeted therapy medicines attack specific chemicals present in cancer cells. By blocking these chemicals, targeted therapy medicines cause cancer cells to die. Some people with dermatofibrosarcoma protuberans have cancer cells that produce an excess protein. A medicine called imatinib (Gleevec) can target those cells and cause them to die. Your health professional may recommend this treatment if surgery is not an option or if your cancer returns after surgery.
Clinical trials. Clinical trials to test new treatments may be an option. Ask your health professional whether you're eligible to participate in a clinical trial.