Dermatofibrosarcoma protuberans

The cause of DFSP is unknown but an injury to the affected skin may be a predisposing factor. Trauma at the affected site has been reported in approximately 10-20% of patients. Recent advances have shown that in approximately 90% of cases, dermatofibrosarcoma protuberans is associated with a rearrangement (translocation) of genetic material between chromosomes 17 and 22 which results in the fusion of two genes. The fused gene produces a protein which some believe may stimulate cells to multiply, leading to the tumor formation seen in dermatofibrosarcoma protuberans. This type of gene change is generally found only in tumor cells and is not inherited.

If dermatofibrosarcoma protuberans spread to other parts of the body, the signs and symptoms vary depending on the size of the metastatic tumor and which organ it affects. Regular physical examinations can help detect recurrence of the tumor in the original location or signs that it has spread to other parts of the body. The physical examination includes a skin examination to look for any changes in the skin's appearance and to feel for any differences in the tissues underneath the skin. Special attention is given to the original site of the tumor and nearby lymph nodes. A sign of spread to the lymph nodes is a firm, movable mass near the original location of the tumor.

Dermatofibrosarcoma protuberans is a slow-growing tumor and does not usually spread to distant parts of the body (metastasize). The overall rate of distant metastasis is estimated to be around 4%, and the rate of metastasis to nearby lymph nodes is 1%.

Dermatofibrosarcoma protuberans has an average recurrence rate of 15.7% after being removed by standard surgery known as wide local excision (when the entire tumor and some of the surrounding normal tissue are removed). Most local recurrences occur within 3 years. Recent studies suggest that a newer surgical technique, Mohs’ micrographic surgery, may help reduce this recurrence rate to approximately 1.3%.

Dermatofibrosarcoma protuberans can affect other organs if it spreads (metastasizes) beyond the original location of the tumor in the skin. The most common site of metastasis for this tumor is the lungs. Shortness of breath can be a sign of lung metastasis.

There is up to a 1% chance that dermatofibrosarcoma protuberans could spread (metastasize) through the lymph system. When cancer cells spread by the lymph, they collect in lymph nodes near the original site of the tumor. As these cells accumulate in a lymph node, the node swells to form a lump or bump that feels firm and is usually painless. A growing mass is a sign that cancer cells may have spread by the lymph system.

Dermatofibrosarcoma protuberans is an uncommon cancer in which tumors arise in the deeper layers of skin. The tumor usually starts as a small, firm patch of skin; it may be purplish, reddish, or flesh-colored. It is commonly found on the torso, usually in the shoulder and chest area. The tumor typically grows slowly but has a tendency to recur after being removed. It rarely spreads to other parts of the body. The cause of DFSP is unknown, but injury to the affected skin may be a predisposing factor. Treatment usually involves surgically removing the tumor. If the tumor is unable to be removed completely, additional therapy may be needed. Regular follow-up is important to monitor for recurrence.

Regular follow-up is needed after tumor removal to monitor for recurrence. Local recurrences arise in 11-20% of cases, usually within three years of the initial surgery. Despite being locally aggressive, the tumor spreads to other parts of the body (metastasizes) in only 5% of cases. A small subset of patients with DFSP have a more aggressive variant known as fibrosarcomatous dermatofibrosarcoma protuberans or FS-DFSP. FS-DFSP tumors are more likely to metastasize than the tumors in other types of dermatofibrosarcoma protuberans.