Chemotherapy treatment patterns and clinical outcomes in patients with metastatic soft tissue sarcoma. The SArcoma treatment and Burden of illness in North America and Europe (SABINE) study

Background: To describe chemotherapy treatment patterns and clinical outcomes in metastatic soft tissue sarcoma (mSTS) patients with favorable response to chemotherapy. Patients and methods: Multicenter (25) multi-country (9) retrospective chart review of mSTS patients with favorable response to chemotherapy, defined as stable disease or better following four cycles. Results: Two hundred and thirteen patients (58% female; mean age 54.7 years) received a mean of 2.7 lines of chemotherapy and 5.2 cycles per line. The most common first-line regimens were doxorubicin (34%) and anthracycline plus ifosfamide (30%). Favorable response was achieved by 83% to first-line and 42% and 38% in second-and third-line chemotherapy. The most common reason for chemotherapy discontinuation in lines with a favorable response was reaching a predefined number of cycles in first line (64% of 213) and disease progression in second or later lines (41% of 138). The mean time off chemotherapy was 38.0 weeks after first line, falling to 2.7-6.4 weeks in second or later lines. Median overall and progression-free survival were 23.5 (95% confidence interval 20.5-28.1) and 8.3 (7.4-9.9) months from first favorable response to chemotherapy. Conclusions: mSTS patients achieving favorable response to chemotherapy have poor outcomes. Additional treatment options are needed.