Adjuvant chemotherapy in soft tissue sarcoma (STS): A meta-analysis of published data

Abstract

10526 Background: The beneficial use of adjuvant chemotherapy to reduce risk of recurrence and mortality in soft tissue sarcoma STS is still controversial. Data from one meta-analysis (doxorubicin based) showed improved relapse free survival (RFS), but not overall survival (OS). We performed a non individual meta-analysis from the published studies to evaluate if adjuvant doxorubicin − / + ifosfamide improves 5- 10 years DFS and OS in STS. Methods: We performed a review of the available literature identified from multiple databases. The key words used were “soft tissue sarcoma”, “adjuvant chemotherapy” and “randomized trial”. Data were pooled for Meta-analysis using the Peto’s Odds Ratio (OR). Event-based relative odds ratios (OR) with 95% confidence intervals (CI) were derived. A heterogeneity test was applied. A subgroup analysis according to ifosfamide or non ifosfamide regimen was also performed. Results: We included one meta-analysis (SMAC 1997), and four published or presented randomized controlled phase III trials (EORTC 62931, 2 Italian studies and one Austrian study) were selected including a total of 2170 patients. Endpoints of interest for this meta-analysis were: Disease-Free Survival (DFS), Recurrence Free-Survival (RFS) and Overall Survival (OS) at 5 and 10 years. Results are summarized in the table below. Conclusion: This meta-analysis supports previous data stating that adjuvant doxorubicin +/ - ifosfamide regimens are significantly beneficial in terms of DFS and OS at 5 years. We observed a tendency to improved survival at 10 years in the adjuvant arm. The addition of modern regimens with ifosfamide did not improve the data of the previous meta-analysis with doxorubicin based-chemotherapy. End point OR (Odds Ratio) 95% CI P value DFS 5 years 0.71 0.54 - 0.85 0.000 RFS 5 years 0.75 0.61 - 0.92 0.007 OS 5 years 0.79 0.66 - 0.94 *0.005 RFS 10 years 0.71 0.58 - 0.85 0.000 OS 10 years 0.87 0.72 - 1.04 0.12 * Heterogeneity p=0.005. Other comparisons NS for heterogeneity. No significant financial relationships to disclose.