Imaging of Soft Tissue Tumors

Abstract

Soft tissue tumors (STTs) arise from mesenchymal tissues and can occur in various body regions. They make up 4% of adult neoplasms and 7-10% of childhood neoplasms, with most being benign. Factors like genetics, environmental influences, and syndromic conditions contribute to their development. The WHO's 2020 classification divides STTs into eleven groups based on genotypic and phenotypic traits, categorizing them into malignant, intermediate, and benign tumors. Imaging is crucial for STT diagnosis and management. While traditional radiographs help detect lesions and calcifications, advanced imaging techniques like ultrasonography (US), computed tomography (CT), and magnetic resonance imaging (MRI) provide detailed evaluations. MRI is particularly valuable, offering comprehensive information about the lesion’s location, content, and relationship with surrounding tissues, using advanced sequences like T1- and T2-weighted imaging, MR perfusion, spectroscopy, and diffusion MRI. US is useful for superficial lesions and guiding interventional procedures, while CT is advantageous for complex anatomical assessments. Diagnosis involves a thorough clinical history, physical examination, and systematic radiological evaluation. Specific STTs have distinct imaging features. Synovial sarcoma appears as a heterogeneous mass near joints, often with increased contrast enhancement. Liposarcomas show significant fatty content with enhancing septa or nodules. Peripheral nerve sheath tumors (PNSTs), such as schwannomas and neurofibromas, present as fusiform masses on MRI. Hemangiomas are identified by high signal intensity on T2-weighted MRI, and giant cell tumors of the tendon sheath (GCTTS) show low signal intensity due to hemosiderin. In summary, a multidisciplinary approach with advanced imaging techniques, especially MRI, is essential for accurate diagnosis and effective management of STTs.