Single-Center Experience with Ifosfamide Monotherapy as Second-Line Treatment of Recurrent/Metastatic Osteosarcoma.

BACKGROUND: The effectiveness of second-line palliative chemotherapy in patients with recurrent/metastatic osteosarcoma is not well defined. Several small studies (6-19 patients) have reported on ifosfamide as second-line treatment. In this study we report our single-center experience with second-line ifosfamide monotherapy in patients treated for recurrent/metastatic osteosarcoma. METHODS: A chart review was conducted of all patients with osteosarcoma treated with ifosfamide from 1978 until 2017. Until 1997 a 5 g/m2 regimen was used, and from 1997 onwards a 9 g/m2 regimen was used. Overall survival (OS) from start of ifosfamide was the primary endpoint. Progression-free survival (PFS) from start of treatment was also studied. To assess difference in survival between groups the log rank test was applied. To investigate the effect of ifosfamide dose and World Health Organization performance status (PS) a Cox proportional hazard regression model was estimated. RESULTS: Sixty-two patients were selected with recurrent/metastatic osteosarcoma treated with second-line ifosfamide monotherapy (dose of 5 g/m2 , n = 26; 9 g/m2 , n = 36). OS was significantly better in univariate analysis for 9 g/m2 compared with 5 g/m2 (10.9 months [95% confidence interval (CI), 9.3-12.6] vs. 6.7 months [95% CI, 5.9-7.6], respectively) and for PS (median OS PS 0, 13.0 months [95% CI, 2.3-23.8]; PS 1, 8.2 months [95% CI, 5.4-11.1]; PS ≥2, 6.2 months [95% CI, 2.2-10.3]; and unknown PS, 5.4 months [95% CI, 2.2-8.5]). In multivariate analysis only PS showed a significant difference. No difference in PFS was found between 5 and 9 g/m2 ifosfamide treatment or PS. CONCLUSION: This study suggests that ifosfamide is an effective second-line treatment for patients with recurrent/metastatic osteosarcoma. IMPLICATIONS FOR PRACTICE: Ifosfamide monotherapy is commonly used as second-line treatment in osteosarcoma, although large series to support this are lacking. This retrospective study reports overall and progression-free survival for regimens with 5 g/m2 and with 9 g/m2 . This study was unable to show a significant difference in survival between 5 and 9 g/m2 but showed an important impact of World Health Organization performance status on overall survival. This study sets a standard and reference for comparison with the multiple phase II studies under development.

Survival of soft tissue sarcoma patients after completing six cycles of first-line anthracycline containing treatment: an EORTC-STBSG database study.

BACKGROUND: Doxorubicin based chemotherapy is standard first line treatment for patients with soft tissue sarcoma. Currently several options to improve survival after doxorubicin based chemotherapy are being studied. This study reports on survival after completing 6 cycles of doxorubicin containing first line treatment, which is important when designing studies trying to improve outcomes of first line treatment. METHODS: A retrospective database analysis was performed on 2045 patients from 12 EORTC sarcoma trials (inclusion period 1980-2012) receiving first line doxorubicin based chemotherapy for advanced soft tissue sarcoma in order to establish progression free survival and overall survival after completing 6 cycles of first line doxorubicin based chemotherapy. Endpoints were overall survival and progression free survival. Factors studied were histologic subtype and type of doxorubicin chemotherapy. RESULTS: 748 of 2045 (36.6%) received at least 6 cycles and did not progress during or at the end of chemotherapy. 475 of 2045 (23.2%) of patients received exactly 6 cycles and did not progress during or at the end of chemotherapy. Median progression free survival after 6 cycles of doxorubicin based chemotherapy was 4.2 months (95% confidence interval 3.7-4.8) and median overall survival 15.7 months (14.0-17.8). Median progression free survival and overall survival from randomisation/registration were 8.7 months (95% confidence interval 8.2-9.1) and 20.1 months (95% confidence interval 18.3-22.3) respectively. Significant differences in progression free survival were found between chemotherapy regimens, but not for overall survival. These data are also reported for patients receiving 7 or more cycles of chemotherapy and for patients with 3 or more cycles of chemotherapy. CONCLUSION: This large retrospective study is the first to report progression free survival and overall survival after completion of 6 cycles of first line doxorubicin containing chemotherapy. These results are important when designing new studies exploring for example maintenance therapy after doxorubicin based chemotherapy.