INTRODUCTION

Sarcomas are a rare and heterogeneous group of malignant tumors of mesenchymal origin that comprise less than 1 percent of all adult malignancies and 12 percent of pediatric cancers [1-3]. Approximately 80 percent of new cases of sarcoma originate from soft tissue, and the rest originate from bone [3].
The histopathologic spectrum of sarcomas is broad, presumably because the embryonic mesenchymal cells from which they arise have the capacity to mature into striated skeletal and smooth muscle, adipose and fibrous tissue, bone, and cartilage, among other tissues. Although ectodermal in origin, malignant tumors affecting peripheral nerves are included because of similarities in their clinical behavior, management, and outcome.

This topic review will cover the clinical presentation, diagnostic evaluation, and staging of soft tissue sarcoma other than gastrointestinal stromal tumor (GIST), the most common sarcoma, which is discussed in detail elsewhere. Issues specific to soft tissue sarcomas arising in the head and neck, retroperitoneum, and breast are discussed elsewhere, as are bone sarcomas, Kaposi sarcoma, and dermatofibrosarcoma protuberans (DFSP). (See "Head and neck sarcomas" and "Clinical features, evaluation, and treatment of retroperitoneal soft tissue sarcoma" and "Breast sarcoma: Epidemiology, risk factors, clinical presentation, diagnosis, and staging" and "Osteosarcoma: Epidemiology, pathogenesis, clinical presentation, diagnosis, and histology" and "AIDS-related Kaposi sarcoma: Staging and treatment" and "Classic Kaposi sarcoma: Clinical features, staging, diagnosis, and treatment" and "Dermatofibrosarcoma protuberans: Epidemiology, pathogenesis, clinical presentation, diagnosis, and staging".)