Soft-tissue malignant fibrous histiocytoma (high-grade undifferentiated pleomorphic sarcoma) arising in a desmoid tumor in a patient with Milroy’s disease

Abstract

Malignant fibrous histiocytoma, now termed high-grade undifferentiated pleomorphic sarcoma, is a term used to refer to a group of malignant soft-tissue tumors characterized by a storiform or cartwheel-like growth pattern [1–4]. This lesion is the most common malignant soft-tissue tumor of adult life, representing approximately 25% of all soft tissue sarcomas [5]. The undifferentiated pleomorphic sarcoma will demonstrate a wide range of histological appearances, and is often further subclassified, although in general large and deep lesions have a poorer prognosis [1]. Desmoid tumors are benign, locally aggressive, softtissue tumors that typically arise in association with fascia, aponeurosis and associated muscle. Often termed musculoaponeurotic fibromatosis, these non-metastasizing lesions show an infiltrative pattern of growth and a significant predilection for local recurrence [6, 7]. We report the extremely unusual association of an undifferentiated pleomorphic sarcoma arising within a desmoid tumor in a patient with Milroy’s disease (chronic hereditary lymphedema of unknown origin). To our knowledge, there have been no similar previous reports. Case report