Leiomyosarcoma of the Head and Neck<subtitle>A Population-Based Analysis</subtitle>

Objectives To describe the characteristics of head and neck leiomyosarcoma and to identify factors associated with survival. Design Retrospective population-based study. Patients The 17-registry Surveillance, Epidemiology, and End Results database was used to identify 578 patients with leiomyosarcoma of the head and neck. Interventions Surgery and primary and adjuvant radiotherapy. Main Outcome Measures Patient demographics and tumor characteristics were examined. Treatment modalities were compared, and survival was assessed using the log-rank test. Results The mean age at diagnosis was 64 years. Most tumors were smaller than 5 cm in greatest dimension (87%) and high grade (44% were moderately differentiated and 39% were poorly differentiated). The primary tumor demonstrated deep extension in 39% of cases, and 2% had lymph node metastases. The most common primary site was the skin and soft tissue of the head and neck (83%). Surgical treatment was provided to 89% of patients, 14% received adjuvant radiotherapy, and 4% received radiotherapy alone. The median observed survival was 84.7 months. The 5-year disease-specific survival rate was 87.6% in patients with well-differentiated tumors, 85.7% in patients with moderately differentiated tumors, and 52.7% in patients with poorly differentiated tumors (P Conclusions Leiomyosarcoma typically presents in older patients; it is often poorly differentiated; and improved survival is associated with surgical treatment.