Second-generation trials (postifosfamide)
Subsequent chemotherapy trials were performed using anthracycline and ifosfamide combinations in patients who primarily had extremity or truncal soft tissue sarcomas. The data are conflicting, and the issue is still not settled. In a small feasibility study, 59 patients with high-risk soft tissue sarcomas, 58 of whom had an extremity or trunk as the primary site, underwent primary resection plus PORT and were randomly assigned to observation versus a dose-dense regimen of six 14-day courses of ifosfamide, dacarbazine (DTIC), and doxorubicin (IFADIC regimen) with granulocyte colony-stimulating factor (G-CSF) bone marrow support and mesna uroprotection. There were no statistically significant differences in OS or relapse-free survival (RFS), but the study was severely underpowered.
In a second trial performed by the Italian National Council for Research, high-risk patients were treated with local therapy (i.e., wide resection plus preRX or PORT, or amputation as clinically necessary) and were then randomly assigned to observation versus five 21-day cycles of 4-epidoxorubicin (epirubicin) plus ifosfamide (with mesna and G-CSF).[25,29] Based on power calculations, the planned study size was 190 patients, but the trial was stopped after 104 patients had been entered because an interim analysis revealed a statistically significant (P = .001) difference in DFS favoring the chemotherapy arm. By the time of the initial peer-reviewed report of the study, the DFS still favored the chemotherapy group (median DFS of 48 months vs. 16 months), but the P value had risen to .04.
Although there was no difference in metastasis-free survival at the time of the report, there was an improvement in median OS (75 months vs. 46 months, P = .03). However, at the follow-up report (at a median of 89.6 months in a range of 56–119 months), OS differences were no longer statistically significant (58.5% vs. 43.1% [P = .07]). The DFS difference had also lost statistical significance (47.2% vs. 16.0% [P = .09). In summary, the trial was underpowered because it was stopped early, and the early promising results that led to stopping the trial diminished as the trial matured.