Overview

Dermatofibrosarcoma protuberans (DFSP) is a very rare type of skin cancer that begins in connective tissue cells in the middle layer of your skin (dermis).

Dermatofibrosarcoma protuberans may at first appear as a bruise or scar. 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.

Diagnosis

Tests and procedures used to diagnose dermatofibrosarcoma protuberans include:

• Skin examination. Your doctor will carefully inspect your skin to understand your condition.
• Skin biopsy. Your doctor will remove a small amount of tissue for testing. Specialized laboratory tests can determine if cancer cells are present.
• Imaging tests. In certain cases, your doctor may recommend imaging tests, such as an MRI, to better understand the extent of your 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. For most cancers, your doctor may recommend a procedure to remove the cancer and some of the healthy tissue that surrounds it (excisional surgery with a normal margin of tissue). This makes it more likely that all of the cancer cells are removed during surgery.

• Mohs surgery. Mohs surgery is a specialized type of surgery that involves progressively removing thin layers of cancer-containing skin until only cancer-free tissue remains. After each layer of skin is removed, it's examined for signs of cancer. The process continues until there are no signs of cancer.

  Mohs surgery may be particularly helpful for treating larger cancers because dermatofibrosarcoma protuberans tends to grow in an irregular shape that makes it difficult to remove completely.

• Radiation therapy. Radiation therapy uses powerful energy beams, such as X-rays and protons, to kill cancer cells. Your doctor may recommend radiation therapy if all of your cancer couldn't be removed during surgery.
• Targeted therapy. Targeted therapy uses drugs that attack cancer cells by focusing on particular traits that make them vulnerable. Some people with dermatofibrosarcoma protuberans have cancer cells that produce an excess protein. A drug called imatinib (Gleevec) can target those cells and cause them to die. Your doctor may recommend this treatment if your cancer returns after surgery.
• Clinical trials. Clinical trials to test new treatments may be an option. Ask your doctor whether you're eligible to participate in a clinical trial.