High-dose chemotherapy in patients with high-risk Ewing's sarcoma of pelvis. A single-centre experience

This study was initiated in an attempt to improve EFS in pts with high-risk pelvic ES using an intensive treatment program of short duration and HDCT followed by autoPBSCT. From January 1996 to November 2008 27 pts (M/F-11/16) with highrisk pelvic ES (localized 21 pts, metastatic 9 pts (only lungs-2, combined-7) received HDCT with autologous transplantation as a consolidation. The median primary tumor volume (PTV) was 739 cm. CT consisted of 5 courses: 1, 3, and 5 included cyclophosphamide 2100 mg/[m.sup.2]/day on days 1,2, doxorubicin 37.5 mg/[m.sup.2] as a 24-hour infusion on days 1,2, and vincristine 1.5 mg/[m.sup.2] on days 1, 8, and 15. Cycles 2 and 4 consisted of ifosfamide 2400 mg/[m.sup.2]/day on days 1-5 and VP-16 100 mg/ [m.sup.2]/day on days 1-5. No G-CSF was given routinely between cycles. Radiation therapy was given after the fifth cycle of CT at athe median dose of 52 Gy (range, 50-56). Patients with lung involvement uniformly received lung irradiation after the second cycle of CT at a dose of 10.8-12 Gy. As a consolidation all pts received busulfan 16 mg/kg, melphalan 140 mg/[m.sup.2]-based high-dose chemotherapy (HDCT) (n = 8); with the addition of thiotepa (TT) 600-900 mg/[m.sup.2] (n = 10) or etoposide (VP16) 1400 mg/[m.sup.2] (n = 9) followed by autologous stem cell rescue (6.4 (1.9-25.3) x [10.sup.6] CD34+ cells/kg). Median number of days to WBC>1.0x[10.sup.9]/l and Plt>20 and 50 x [10.sup.9]/l was 10 (8-14), 16 (0-52) and 28 (11-66) days, respectively. TRM was 11% (3 pts out of 27). Eight pts relapsed (5 of them with primary metastatic disease). EFS and DFS were 58% and 66% with a median followup of 86 and 96 mo, respectively. EFS and DFS in TT, VP16 and BuMel groups were 56%, 50% and 73% and 63%63% and 73%, respectively. One pt had ileus 3 mo after BMT and had successful surgery. Our results support the hypothesis that pts with high-risk pelvic ES may benefit from BuMel-based regimens and that an addition of any drug to BuMel regimen increases a toxicity with no influence to DFS. Supported by Ronald McDonald House Charities.