OBJECTIVES: To describe the characteristics of @entity135 and to identify factors associated with survival. DESIGN: Retrospective population-based study. @entity1 : The 17-registry Surveillance, Epidemiology, and End Results database was used to identify 578 @entity1 with @entity1822 of the head and neck. INTERVENTIONS: Surgery and primary and adjuvant radiotherapy. MAIN OUTCOME MEASURES: @entity1 demographics and @entity5 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 @entity5 were smaller than 5 cm in greatest dimension (87%) and high grade (44% were moderately differentiated and 39% were poorly differentiated). The @entity5 demonstrated deep extension in 39% of cases, and 2% had lymph node @entity3 . The most common primary site was the skin and soft tissue of the head and neck (83%). Surgical treatment was provided to 89% of @entity1 , 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 @entity1 with well-differentiated @entity5 , 85.7% in @entity1 with moderately differentiated @entity5 , and 52.7% in @entity1 with poorly differentiated @entity5 (P < .001). Survival was better for @entity1 who received surgery alone (median survival, 100.1 months [n = 413]) than for those who received radiotherapy alone (median survival, 16 months [n = 16]) or adjuvant radiotherapy (median survival, 64.2 months [n = 80]) (P < .001). The latter group was more likely to have poorly differentiated, large, locally invasive @entity5 . CONCLUSIONS: @entity1822 typically presents in older @entity1 ; it is often poorly differentiated; and improved survival is associated with surgical treatment.

XXXX of the head and neck: a population-based analysis.

@entity1 :: ('9606', 'Species') :: ['patients', 'PATIENTS', 'Patient'] @entity135 :: ('MESH:D006258', 'Disease') :: ['head and neck leiomyosarcoma'] @entity5 :: ('MESH:D009369', 'Disease') :: ['tumor', 'primary tumor', 'tumors'] @entity1822 :: ('MESH:D007890', 'Disease') :: ['leiomyosarcoma', 'Leiomyosarcoma'] @entity3 :: ('MESH:D009362', 'Disease') :: ['metastases']
@entity1822 :: (MESH:D007890,Disease) :: ['Leiomyosarcoma']
