Soft-Tissue Sarcoma

Soft-tissue sarcomas (STS) are rare heterogeneous tumors of mesenchymal origin arising in connective tissues, representing less than 1% of adult malignancies. Due to their varied subtypes, they are a challenge to diagnose and treat. Sarcomas are classified according to the “World Health Organization Classification of Tumours of Soft Tissue and bone” providing universal nomenclature for use worldwide. Each subtype of STS has common clinical, therapeutic and prognostic features. Extremities are the most common site for STS, accounting to up to 60%, followed by trunk (19%), retroperitoneum (15%) and head and neck (9%). Approximately 80% arise in soft tissue and the rest from connective tissues within the bone. The etiology of most STS is still unknown. In few cases, genetic and environmental factors such as exposure to chemicals (e.g., vinyl chloride, arsenic), exposure to radiation, viral infection (Herpes virus), immunodeficiency (Epstein–Barr virus), prior injury (scars, burns), chronic tissue injury, neurofibromatosis and certain germ line mutations (Li–Fraumeni syndrome (p53 mutations), RB1 gene mutations) can lead to variants of STS. Given their low incidence, most clinicians and pathologists have limited experience in their presentation which can lead to delay in diagnosis and treatment. The overall 5-year survival rate for STS in extremities is 65–75%. In this chapter, we outline the current principles of diagnosis and treatment protocols for STS.