OBJECTIVETo analyze the clinical features, treatment and prognosis of Stage IV alveolar soft part sarcoma.

METHODSTo analyze the clinical and pathological features, therapeutic methods and follow-up results in 21 patients with stage IV alveolar soft part sarcoma. There were 11 males and 10 females, in the age of 26-57 years (average 37.0 years old). All the 21 patients had metastasis: nine cases had multiple pulmonary metastasis, three cases had multiple pulmonary and brain metastasis, two cases had multiple brain metastasis, two cases had multiple pulmonary and bone metastasis, two cases had single pulmonary metastasis, one case had single bone metastasis, one case had single brain metastasis and one case had single soft tissue metastasis. Eight patients were treated by surgical operation, including five cases of complete resection for the primary and (or) metastatic tumor and 3 cases of palliative operation for the primary tumor. All patients received chemotherapy, including seven cases of CAVD regimen and 14 cases of MAID regimen treatment. One patient with single bone metastasis and five patients with multiple brain metastasis received post-operative whole brain radiation therapy.

RESULTSAll the eight patients with surgical operation had healing by first intention, and pathological examination showed that seven patients achieved R0 surgical margin and one case with R2 status. One patient with single brain metastasis had recurrence after operation. The toxic and adverse reactions of all patients treated with chemotherapy were tolerable. Among them, 17 cases had stable disease and 4 cases had disease progression after chemotherapy. The disease control rate (DCR) was 81.0%. The DCR of patients with CAVD regimen chemotherapy was 85.7% and that of patients treated with MAID regimen was 78.6% (P = 0.862). All patients were followed up for 8 - 86 months (average 32.4 months). The median survival time of all patients was 32.6 months. The 2-year survival rate was 55.1% and the 5-year survival rate was 21.8%. The median survival time in the patients with complete resection was 60.0 months, and that in patients with palliative operation was 27.0, showing a significant difference between them (P = 0.048). The median progression-free survival in patients with complete excision was 57.2 months and that in patients with palliative operation or without operation was 19.6 months, with a significant difference (P = 0.029). The median survival time in patients who received CAVD regimen chemotherapy was 30.0 months, and that in patients with MAID regimen was 51.0 months, with a non-significant difference (P = 0.511). The median progression-free time in patients with CAVD regimen chemotherapy was 13.0 months, and that in patients with MAID regimen was 38.0 months, also with a non-significant difference (P = 0.066).

CONCLUSIONSAlveolar soft part sarcomas are rarely seen and highly malignant tumors, and the prognosis of stage IV ASPS is poor. Complete resection of all tumors is the key of successful treatment of Stage IV ASPS, and the site and number of tumor metastasis are important factors affecting prognosis. The curative effects of radiotherapy and chemotherapy for ASPS need to be further investigated.