Dermatofibrosarcoma Protuberans (DFSP)

Dermatofibrosarcoma protuberans is a type of sarcoma that begins in the connective tissue cells in the middle layer of skin (dermis). The condition is relatively rare, accounting for less than 0.1% of all cancers and about 1% of all soft tissue sarcomas. In the United States, only about 1 to 5 cases are diagnosed per million people each year.

DFSP tends to grow slowly. When detected early, it is highly treatable and can often be cured. However, if left untreated, the tumor can become locally aggressive, potentially spreading into the surrounding fat, muscle and other tissues.

What are the causes and risk factors for dermatofibrosarcoma protuberans?

Scientists have linked DFSP to a specific genetic change involving the rearrangement of chromosomes 17 and 22, which promotes tumor growth. This gene mutation is identified in approximately 90% of cases, although the exact cause remains uncertain.

DFSP is not inherited, and most people who develop the condition do not have any identifiable risk factors. Though highly uncommon, it may develop in an area of skin affected by a prior injury or scar resulting from:

• A burn
• Prior radiation therapy
• A surgical incision
• A tattoo

Is dermatofibrosarcoma protuberans preventable?

DFSP is caused by a nonheritable genetic mutation that has not been linked to any lifestyle choices, such as poor diet, lack of exercise or smoking. For this reason, the condition cannot be prevented. To help ensure an early diagnosis, it is important to have regular skin checks and stay alert to any unusual or persistent skin changes, which should be promptly discussed with a physician.

What are the signs and symptoms of dermatofibrosarcoma protuberans?

Recognizing the symptoms of DFSP can help ensure early detection and effective treatment. In many cases, the condition first appears as a slow-growing skin lesion or a painless lump.

What are the early warning signs of dermatofibrosarcoma protuberans?

In its earliest stages, DFSP can be easily mistaken for a more common and less serious skin condition, such as a scar or cyst. Therefore, it is important to be vigilant for early warning signs, such as:

• A small, flat or slightly raised patch of skin
• A firm lump under the skin
• Subtle variations in skin color, such as shades of violet or reddish-brown in a limited area

What are the most common symptoms of dermatofibrosarcoma protuberans?

As DFSP continues to develop, it may cause more noticeable changes in the skin and underlying soft tissues. Common symptoms include:

• A rubbery lump on the head, neck, trunk, arm or leg
• A firm lump under the skin that steadily increases in size over time
• A raised, irregular or discolored skin patch that may resemble a scar or bruise

What are the symptoms of advanced dermatofibrosarcoma protuberans?

As DFSP progresses, the tumor may grow larger and invade deeper layers of tissue. Symptoms of advanced DFSP include:

• A bulky, protruding tumor that may ulcerate or bleed
• Pain or tenderness as the tumor invades deep structures
• Limited mobility, if the tumor affects a nearby joint or muscle

What are some signs that dermatofibrosarcoma protuberans has spread?

Though rare, DFSP can potentially metastasize, typically to the lungs. Possible warning signs of cancer spread include:

• A persistent cough, shortness of breath or chest discomfort
• Unexplained fatigue or weight loss
• The appearance of new lumps in different areas of the body

How is dermatofibrosarcoma protuberans diagnosed?

Because DFSP can resemble many other skin conditions, an accurate diagnosis requires testing. Usually, the diagnostic process involves a combination of laboratory analysis, imaging studies and biopsy.

What laboratory tests are used to diagnose dermatofibrosarcoma protuberans?

Lab testing can help the physician confirm DFSP at the cellular and genetic level. Diagnostic lab tests may include:

• Biopsy with pathology testing to examine the tumor cells under a microscope
• Genetic analysis to check for the COL1A1-PDGFB fusion gene specific to DFSP

What imaging tests are used to diagnose dermatofibrosarcoma protuberans?

Imaging can help the physician determine the extent of DFSP and whether it has spread. Imaging studies may include:

• Magnetic resonance imaging (MRI) scans to map the tumor depth and involvement of nearby tissues
• Computed tomography (CT) scans, if cancer spread to the chest or lungs is suspected
• Ultrasound for evaluating the tumor boundaries beneath the skin

What procedures are used to diagnose dermatofibrosarcoma protuberans?

Diagnostic procedures are usually performed to obtain tissue samples and ensure accurate testing. Options may include:

• Punch or excisional biopsy to remove part or all of the suspicious lesion for microscopic examination by a pathologist
• Wide local excision to remove the entire tumor with margins for both diagnostic and treatment purposes

How is dermatofibrosarcoma protuberans treated?

DFSP treatment can vary depending on the location, size and extent of the tumor. Most patients benefit from a multispecialty approach that may involve surgery, radiation therapy, targeted therapy or participation in a clinical trial.

How is surgery used to treat dermatofibrosarcoma protuberans?

Surgery is the primary and most effective treatment for DFSP. Surgical options may include:

• Wide local excision, which involves removing the tumor along with a small margin of surrounding tissue
• Mohs micrographic surgery, which involves removing and examining the lesion layer by layer to ensure all cancerous cells are removed while sparing healthy tissue
• Reconstructive surgery, such as a skin graft or flap, which can improve function and appearance after a large tumor is removed

How is radiation therapy used to treat dermatofibrosarcoma protuberans?

In certain cases, radiation therapy may be used as a supplement to surgery to:

• Shrink the tumor and make it easier to remove
• Target residual cancer cells after incomplete tumor removal

Radiation therapy may also be used to provide symptom relief in an advanced case of DFPS.

How is targeted therapy used to treat dermatofibrosarcoma protuberans?

Targeted therapy is an important treatment option for certain patients with advanced, recurrent or inoperable DFSP. Options may include imatinib (Gleevec®), a medication that can block the abnormal proteins fueling tumor growth. Additional targeted drugs for resistant DFSP cases are currently under study in clinical trials.

How is chemotherapy used to treat dermatofibrosarcoma protuberans?

Chemotherapy is not a standard treatment for DFSP. However, it may be considered in an advanced case if:

• The cancer has not responded to other treatment options
• The tumor has spread beyond the skin and surgical removal is not possible

How is immunotherapy used to treat dermatofibrosarcoma protuberans?

Immunotherapy is not widely used for DFSP, but research is ongoing. Clinical trials may explore the role of this emerging treatment for dermatofibrosarcoma protuberans and other rare sarcomas.

Are there other treatment options for dermatofibrosarcoma protuberans?

Beyond standard therapies, some patients may benefit from additional or supportive care options, which may include:

• Clinical trials, which may provide access to promising new targeted therapies, immunotherapies or combination treatments not yet widely available in other settings
• Repeat surgery, which may be required in a case of cancer recurrence
• Supportive care focused on pain management and quality of life if DFSP cannot be fully removed or has spread

Frequently asked questions (FAQs) about dermatofibrosarcoma protuberans

Due to the unique nature of DFSP, many people have questions about what it is, how it behaves and what treatment involves. Below are answers to some of the most commonly asked questions:

Is dermatofibrosarcoma protuberans cancerous?

Yes. DFSP is a rare form of soft tissue sarcoma, which means it is a type of cancer that originates in the connective tissue of the skin. Although it grows slowly and rarely spreads to other parts of the body, it can be locally aggressive if not treated properly.

Can dermatofibrosarcoma protuberans come back after treatment?

Yes. DFSP recurrence is possible, especially if the tumor is not completely removed during surgery. Because residual cancer cells may grow into the surrounding tissue, the patient will be monitored closely after treatment to detect and address any signs of recurrence early.

What is the prognosis for a patient with dermatofibrosarcoma protuberans?

The prognosis is generally very good. When DFSP is diagnosed and treated early—typically through surgical removal with clear margins—most patients experience an excellent long-term outcome. Regular follow-up appointments can help ensure ongoing monitoring and continued health.

Benefit from world-class care at Moffitt Cancer Center

If you have questions about dermatofibrosarcoma protuberans, you can request an appointment with a specialist in the Cutaneous Oncology Program at Moffitt by calling 1-888-663-3488 or completing our new patient registration form online. We do not require referrals.