Alveolar Soft Part Sarcoma: Clinical Presentation, Treatment, and Outcome in a Series of 33 Patients at a Single Institution

Alveolar soft part sarcoma (ASPS) is a rare soft tissue tumor that usually affects young patients. A comprehensive retrospective review was performed of clinical presentation, treatment, outcome, and patterns of failure in a consecutive series of patients with localized or metastatic ASPS between 1975 and 2008. Demographics, tumor sizes, sites and extent of disease, treatments provided, progression-free survival, and overall survival were evaluated. A total of 33 patients were identified. Preoperative imaging misdiagnosed a vascular malformation in three cases (9%), delaying treatment. The most common location of primary tumor was the thigh. The median diameter of the mass was 9 cm (range, 2-15 cm). The tumor was deeply located in most cases (78.7%). A R0 resection was obtained in 27 cases. Adjuvant radiotherapy was delivered in 12 cases, in 6 cases in association with chemotherapy; preoperative systemic chemotherapy was delivered in 4 cases, in the adjuvant setting in another 3 cases. Twenty-one (63.6%) of 33 patients exhibited metastases either at presentation (10 patients, 30.3%) or later. Metastatic sites included lymph nodes, lung, bone, and liver. Median overall follow-up was 72 months. Overall survival was 68.7% at 5 years and 53.4% at 10 years. Metastectomies were performed in 33% of metastatic cases (7 of 21 patients). Prognosis of ASPS is basically related to the characteristics of the disease and the quality of surgery. Overall, the occurrence of distant metastases is quite common, with a typical indolent course. New agents are eagerly needed to complement surgery to eradicate this disease.