Abdominal and pelvic tumors with musculoskeletal histology.

This article is a case-based review of the broad spectrum of tumors with musculoskeletal histology that can arise in the abdomen or pelvis and involve the soft tissues, muscle, and bone. In this article, pathology-proven cases are presented with a focus on radiographic, computed tomography, magnetic resonance imaging, and positron emission tomography-computed tomography findings. The imaging features that differentiate tumors with musculoskeletal histology from more common abdominal tumors are discussed. Representative cases include malignant fibrous histiocytoma, chondrosarcoma, Ewing sarcoma, hemangiopericytoma, desmoplastic fibroma, neurofibrosarcoma, osteosarcoma, intimal sarcoma, liposarcoma, leiomyosarcoma, synovial sarcoma, teratoma, and chordoma. A variety of tumors with musculoskeletal histology can arise in the abdomen and pelvis. In some cases, unique imaging characteristics allow a confident diagnosis, whereas other cases have a more nonspecific appearance. Recognition of imaging features that suggest a musculoskeletal tumor including direct extension from a bone or neural foramen, the presence of cartilaginous or osseous matrix, or macroscopic fat would allow the radiologist to suggest the proper diagnosis. Recognizing imaging characteristics of tumors with musculoskeletal histology is important clinically as management and prognosis differ from that of more common abdominal tumors.