Objective: Soft tissue sarcoma (STS) originating from the non-extremities has a poor prognosis and risk for visceral crisis; therefore, combination chemotherapy with a high response rate is desired.
Methods: We retrospectively reviewed the cases of 30 patients with advanced STS that originated from the non-extremities who were treated between October 2005 and February 2012 at our institute with the CYVADIC chemotherapy regimen, which consists of cyclophosphamide, vincristine, doxorubicin, and dacarbazine. The patients' objective responses, progression-free survival (PFS), and overall survival (OS) were evaluated, and a statistical analysis was conducted to identify the predictive factors related to response and survival.
Results: The median follow-up time was 16.5 months. The response rate was 33%, the median PFS was 7.4 months, and the 1-year OS was 81% (the OS did not reach the median). The median number of treatment cycles was six. Eleven patients failed to complete 6 cycles due to disease progression. The number of involved organs (>3) was a significant predictive factor of early refractoriness by the logistic regression analysis. Thirteen patients had an objective response or PFS longer than 1 year, and an alkaline phosphatase (ALP) level within the normal limits were the significant predictive factors of a good response.
Conclusion: The patients' responses to the CYVADIC therapy for advanced STS originating from the non-extremities were moderate; therefore, CYVADIC therapy may be a treatment option of choice as combination chemotherapy for such patients. We propose that the number of involved organs and ALP concentration may be useful measures to predict the response to the CYVADIC therapy.