Dermatofibrosarcoma protuberans (DFSP)   is a rare locally aggressive malignant cutaneous soft-tissue sarcoma. DFSP develops in the connective tissue cells in the middle layer of the skin (dermis). Estimates of the overall occurrence of DFSP in the United States are 0.8 to 4.5 cases per million persons per year. In the United States, DFSP accounts for between 1 and 6 percent of all soft tissue sarcomas  and 18 percent of all cutaneous soft tissue sarcomas. In the Surveillance, Epidemiology and End Results (SEER) tumor registry from 1992 through 2004, DFSP was second only to Kaposi sarcoma. Presentation
Dermatofibrosarcoma protuberans begins as a minor firm area of skin most commonly about  to 1 to 5 cm in diameter. It can resemble a bruise, birthmark, or pimple. It is a slow-growing tumor and is usually found on the torso but can occur anywhere on the body. About 90% of DFSPs are low-grade sarcomas. About 10% are mixed, containing a high-grade sarcomatous component (DFSP-FS); therefore, they are considered to be intermediate-grade sarcomas. DFSPs rarely lead to a metastasis (fewer than 5% metastasize), but DFSPs can recur locally. DFSPs most often arise in patients who are in their thirties but this may be due to diagnostic delay. Location
Commonly located on the chest and shoulders, the following is the site distribution of DFPS as was observed in Surveillance, Epidemiology, and End Results (SEER) [1] database between 2000 and 2010.
In 2006 the US FDA approved (imatinib mesylate) for the treatment of DFSP. As is true for all medicinal drugs that have a name that ends in "ib," imatinib is a small molecular pathway inhibitor; imatinib inhibits tyrosine kinase. It may be able to induce tumor regression in patients with recurrent DFSP, unresectable DFSP, or metastatic DFSP. There is clinical evidence that imatinib, which inhibits PDGF-receptors, may be effective for tumors positive for the t(17;22) translocation. It is suggested that imatinib may be a treatment for challenging, locally advanced disease and in the rare metastatic cases It was approved for use by adult patients with unresectable, recurrent and/or metastatic dermatofibrosarcoma protuberans (DFSP). Metastatic disease
Distant hematogenous metastases are extremely rare. Metastases to regional lymph nodes are rarer and are most likely in patients who have had multiple local recurrences after inadequate surgical resection. Repeatedly recurring tumors have an increased risk for transformation into a more malignant form (DFSP-FS). The lungs are most frequently affected, but metastases to the brain, bone, and other soft tissues are reported. Studies
DFSP is not extensively studied due to its rarity and low mortality. The majority of studies are small size case studies or meta-analysis. The most extensive research study to date was Perspectives of Patients With Dermatofibrosarcoma Protuberans on Diagnostic Delays, Surgical Outcomes, and Nonprotuberance. The lead researcher Jerad Gardner spoke at a Ted Talk in February 2020 on the topic. History
Taylor, RW, in 1890. first identified DFSP as a keloid sarcoma.