Malignant fibrous histiocytoma of soft tissue. A population‐based epidemiologic and prognostic study of 137 patients

Epidemiology and prognosis were analyzed in a consecutive, population‐based series of 137 patients with malignant fibrous histiocytoma of soft tissue in the extremities and trunk wall, with a complete follow‐up of minimum 3 years. All but one patient were treated by surgery in 28 cases combined with adjuvant radiotherapy or chemotherapy. The annual incidence was 0.42/10⁵. The ratio men to women was 1.1. The median age was 64 years (range, 22 to 87 years). The thigh was the most common location. The median size was 6 cm. Superficial tumors constituted 43% and were smaller than deep‐seated tumors. Eighty‐three tumors were storiform‐pleomorphic, 53 were myxoid, and one was of inflammatory type. The myxoid tumors were smaller and more often superficial. The cumulative 5‐year survival rate for all patients was 0.7, but differed markedly between the histologic types; it was 1.0 in patients with myxoid tumors and 0.5 in patients with storiform‐pleomorphic tumors. In the 77 patients with storiform‐pleomorphic tumors without metastases at presentation, only tumor size larger than 10 cm and tumor necrosis independently impaired survival. The 23 patients who had none of these risk factors had a 5‐year survival rate of 0.8.