Primary Leiomyosarcoma of Extragnathic Bone: Clinicopathologic Features and Reevaluation of Prognosis

Abstract

Leiomyosarcoma most commonly involves the female genital tract and occasionally arises within the retroperitoneum, abdominal cavity, or the soft tissues of the extremity. Presentation as a primary bone tumor is extraordinarily uncommon, potentially leading to misdiagnosis. The prognosis is traditionally thought to be dismal. However, this conclusion is largely based on individual case reports and small series, in some of which the pathologic diagnosis is not well documented. To review the clinicopathologic features of well-established cases of primary skeletal leiomyosarcoma and reevaluate the prognostic implications thereof. A National Center for Biotechnology Information PubMed search of the English language literature identified 104 authenticated cases of primary leiomyosarcoma of extragnathic bone. An additional 3 cases are reported and illustrated herein. Approximately half of all patients with primary skeletal leiomyosarcoma either presented with metastatic disease or developed metastases within 1 year of diagnosis. The 5-year overall and disease-free survival rates were 59% and 41%, respectively, comparable to that of other skeletal sarcomas. As for other bone and soft tissue sarcomas, high histologic grade and tumor stage are predictive of poor outcome.