SOFT TISSUE SARCOMAS OF EXTREMITIES: A PICTORIAL REVIEW FROM TERTIARY CARE ONCOLOGY SETUP

Abstract

Radiologists are frequently encountered by soft-tissue sarcomas in their daily practice.  Characterization and exact diagnosis of these soft-tissue sarcomas pose a great challenge, despite advances in imaging. By systematically using clinical history and imaging findings such as lesion location, mineralization on radiographs, and imaging characteristics on magnetic resonance images, one can narrow the differential diagnosis. Malignant neoplastic processes can mimic benign lesions and may be difficult to differentiate.

Radiologists should have a thorough knowledge of the imaging characteristics of these lesions to advise on appropriate surgical management. Features that are more common in malignant lesions include large size (> 5 cm), deep site, inhomogeneous signal intensity, haemorrhage and necrosis, early and inhomogeneous contrast enhancement, irregular margins, surrounding soft tissue oedema and invasion of adjacent structures, including bone and neurovascular bundle. Advanced MRI techniques such as spectroscopy, perfusion and diffusion-weighted imaging may contribute to better soft tissue characterisation. If a lesion is lacking characteristic benign features then it should be regarded as indeterminate, and patient should undergo tissue diagnosis to exclude malignancy. Core biopsy is required as fine needle aspiration is inadequate.

In this review article, we have tried to highlight imaging findings of soft tissue sarcomas mainly discussing the MRI imaging and their characteristic findings which can help a radiologist to narrow differential diagnosis before tissue diagnoses.

Key words: Soft tissue sarcoma, imaging, MRI, malignant