Alveolar soft part sarcoma in children and adolescents: clinical features and outcome of 11 patients.

The clinical features and response to therapy of pediatric alveolar soft part sarcoma, a rare soft tissue sarcoma of uncertain histogenesis, have not been previously described in detail in the literature. We retrospectively reviewed the clinical characteristics of all patients with alveolar soft part sarcoma who were seen at our institution over a 32-year period. We found 11 patients with the diagnosis of alveolar soft part sarcoma. Their ages ranged from 2.8-16 years (median 9.8). Staging was determined using the Intergroup Rhabdomyosarcoma Study clinical grouping system and the UICC TNM system. Accordingly, there were six patients with grossly resected tumors (clinical groups I and II) and five with unresected or metastatic disease (clinical groups III and IV). Children with resected disease were more likely to have smaller noninvasive tumors. The main feature predictive of survival was tumor resectability, since chemotherapy in various combinations failed to produce significant tumor responses. Nine patients are disease-free with a median follow-up of 11.9 years. Surgical resection remains the mainstay of therapy for pediatric alveolar soft part sarcoma. Since active chemotherapy agents have not been identified, patients with unresected or metastatic disease may benefit from experimental agents. The survival rate of this cohort is superior to that seen in adults.