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Imaging Features, Differential Diagnosis and Management of Leiomyosarcomas: Case Series and Review of the Literature

Abstract

Stramare R, Orsatti G, Attar S, Rastrelli M, Brunello A, Bortolanza C, Ortolan P and Coran A

Leiomyosarcoma (LMS) is a relatively rare malignant tumor showing smooth-muscle differentiation and accounting for 7-10% of all soft tissue tumors (STTs). LMS occurs most commonly in retroperitoneum and extremities but can potentially involve every site of the body. Diagnosis is finally provided by a histological examination; nevertheless multiplanar imaging can suggest a radiological diagnosis of soft tissue sarcoma prior to biopsy and allow a precise assessment of primary tumor extent and systemic spreading. Computerized tomography (CT) is often the first imaging modality assessment especially for abdominopelvic LMSs and also the cornerstone of staging. CT usually shows a large, heterogeneous and unspecific mass with central areas of hemorrhage or necrosis and peripheral contrast enhancement. Magnetic resonance imaging (MRI) findings are not specific and show a nonfatty mass iso-intense to skeletal muscle on T1-weighted images and high-signal in T2-weighted images with a decreasing rim-to-center pattern of enhancement after gadolinium administration. Imaging also helps in differential diagnosis that mainly concern other STT, gastrointestinal stromal tumors (GISTs), primitive neuroendocrine tumors (PNETs), and lymphomas. Prognosis of LMS is poor and patients should be referred to hospitals with extensive experience in managing sarcomas using multidisciplinary therapeutic approach including surgery, chemotherapy and radiotherapy. The aim of this review is to underline the most important radiological features that could indicate a diagnosis of LMS and in particular to draw the attention to LMSs of the limbs as one of the most frequent location even if often overlooked in literature.