Other Rare Conditions of Pseudotumoral and Benign Lesions of Soft Tissues

Abstract

The myxomas are a group of relatively common, entirely benign probably unrelated lesions, which most commonly involve large muscles (intramuscular myxoma) but may also occur around large joints (juxta-articular myxoma) or in the skin (cutaneous myxoma). All are characterized by abundant myxoid matrix, bland stellate to spindled cells, and hypovascularity. These three morphological features are fundamental to differentiate myxoma to myxoid nodular fasciitis and to malignant myxoid neoplasms, such as myxofibrosarcoma and myxoid liposarcoma [1]. Local, complete excision is adequate treatment, but juxta-articular myxoma may recur locally in 30% of cases, particularly if incompletely excised [1].