[Synovial sarcoma of the right forearm].

We report the case of a 60-year old female patient, followed up for hypertensive heart disease for 04 years, presenting to the Dermatological Department with a mass in the right forearm which had evolved and gradually increased in size over the previous year. Clinical examination showed soft rounded, voluminous painless, tumor-like crusted ulcerative lesion measuring 8 cm in large-diameter, fixed with respect to both planes, at the level of the mid-parts of the posterolateral area of the right forearm (A). Standard X-ray showed homogeneous opaque mass with sparing of the opposite cortex (B). Magnetic resonance imaging showed voluminous multicompartmentalized cystic and tissue cutaneous-subcutaneous process infiltrating the subcutaneous grease and in contact with extensor muscles (C). Histology revealed poorly differentiated sarcomatous pleomorphic cells proliferation (D). Immunohistochemical study confirmed the diagnosis of synovial sarcoma. The patient was referred to the Division of Plastic Surgery for surgical treatment.