Alveolar soft part sarcoma: clinical presentation, treatment, and outcome in a series of 33 patients at a single institution.

BACKGROUND: 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.
METHODS: Demographics, tumor sizes, sites and extent of disease, treatments provided, progression-free survival, and overall survival were evaluated.
RESULTS: 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).
CONCLUSIONS: 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.