Sarcomas are a diverse group of malignant tumors that develop from fat, muscles, nerves, joints, blood vessels, bones, and deep skin tissues. Sarcomas are difficult to differentiate from other malignancies when they are found within organs; thus, they are frequently misdiagnosed and highly underreported. As a result, although the incidence estimates presented here include the best available data, they are probably low. Because sarcomas often afflict people in the prime of life, the number of years of life lost is substantial despite the relatively low incidence. It is estimated that approximately 11,590 Americans will be diagnosed with sarcoma and 4,890 will die from the disease in 2007.

Soft tissue sarcoma and osteosarcoma (bone sarcoma) incidence rates have remained relatively constant over the past 30 years; however, soft tissue sarcoma is more deadly due to the lack of detectable symptoms at early disease stages. Several subtypes of osteosarcoma and soft tissue sarcoma exist; the exact number of Americans with each sarcoma subtype is unknown.