Imaging diagnosis of soft-tissue tumours: current concepts and clinical guidance

Soft tissue tumours (STTs) represent a heterogeneous group of lesions that go from benign entities to aggressive sarcomas. Their variable clinical presentation and low incidence of malignancy make imaging an indispensable tool to both diagnosis and management. This narrative review provides an updated, clinically oriented overview of the diagnostic role and appropriate use of conventional radiography, ultrasonography (US) computed tomography (CT), magnetic resonance imaging (MRI), and hybrid techniques such as positron emission tomography (PET)/CT and PET/MRI of STTs. Emphasis is placed on MRI as the modality of choice for local staging, with attention to emerging functional and multiparametric applications, including diffusion-weighted imaging and dynamic contrast-enhanced studies. The complementary role of CT in detecting calcifications and metastases, as well as the expanding potential of US with elastography and contrast-enhanced applications, are also addressed. In addition, image-guided biopsy (primarily US- and CT-guided) remains essential for histological confirmation and treatment planning. Recent advances such as radiomics and hybrid imaging approaches are discussed for their potential to refine diagnosis, guide therapy, and improve patient outcomes. Strengths and limitations of each modality are outlined, with particular focus on malignant lesions, underscoring the importance of early referral to specialised centres and multidisciplinary management.