Alveolar soft part sarcoma in children and adolescents: The European Paediatric Soft Tissue Sarcoma study group prospective trial (EpSSG NRSTS 2005)

Background: As alveolar soft part sarcomas (ASPS) are rare with no prospective series within pediatric sarcoma trials, the European Paediatric Soft Tissue Sarcoma Study Group (EpSSG) examined the clinical data and outcomes of ASPS enrolled in a multinational study of nonrhabdomyosarcoma soft tissue sarcomas (NRSTS). Patients and methods: Twenty-two patients with ASPS were enrolled into the EpSSG NRSTS 2005 study. After surgical resection, subsequent treatment depended on the stratification of patients for completeness of resection and Intergroup Rhabdomyosarcoma Study (IRS) stage, size, and French Federation of Cancer Centres Sarcoma Group (FNCLCC) grade. Chemotherapy using ifosfamide and doxorubicin was performed in IRS group III. Radiotherapy was performed in IRS groups II and III, and FNCLCC grades 2 and 3 tumors. Results: The median age at diagnosis was 11.5 years (range 2.7-17.5 years). The majority in the series had localized disease (20), with small IRS I tumors (12), and in total 19 had surgical resection upfront. Of the four patients who received conventional chemotherapy, there were no responses. Three of 20 patients with localized tumors and all metastatic patients developed metastases. The median follow up of patients with localized disease is 61.7 months (range 25.7-135.5 months) from diagnosis. The 5-year event-free survival is 94.7% (95% confidence interval: 68.1-99.2), and therefore the overall survival (OS) is 100%. Conclusion: This report demonstrates the ability to run prospective pediatric studies in NRSTS in multiple European countries, despite the small numbers of ASPS patients. We can conclude that for the majority with small resected tumors, there were few events and no deaths.