Ifosfamide-Based Combination Chemotherapy in Advanced Soft-Tissue Sarcoma: A Practice Guideline

Questions: In adult patients with inoperable locally advanced or metastatic soft-tissue sarcoma, do combination chemotherapy regimens containing ifosfamide have an advantage in terms of response rate, time to progression, or survival, as compared with similar regimens without ifosfamide when used as first-line therapy? What are the adverse effects and effects on quality of life of ifosfamide-containing combination chemotherapy as compared with similar regimens without ifosfamide? Perspectives: The prognosis for patients with inoperable or metastatic soft-tissue sarcoma (STS) remains grim. Although the surgical resection of pulmonary metastases may be curative in 15%–30% of patients with isolated slow-growing metastases, most patients receive chemotherapy for palliative purposes. Ifosfamide has documented activity in patients who have received prior treatment with, or who have progressed on, doxorubicin. A number of studies have suggested a schedule and a dose–response relationship for ifosfamide in metastatic STS. Ifosfamide has also been assessed in combination with other drugs such as doxorubicin and dacarbazine (DTIC); results of such studies have led some authors to suggest that polychemotherapy using “appropriate doses” of ifosfamide and doxorubicin may represent the “most effective systemic treatment” in this population. Given the limited effective therapeutic options available for patients with metastatic STS, the Sarcoma Disease Site Group (DSG) felt that a need existed to more specifically evaluate the potential benefits of ifosfamide-containing combination chemotherapy in that setting. The Sarcoma DSG developed an evidencebased series report through systematic review, evidence synthesis, and input from practitioners across Ontario. Outcomes: Outcomes of interest included survival, response rate, adverse events, and quality of life. Methodology: A systematic review and meta-analysis served as the evidentiary base for this clinical practice guideline. The report was reviewed and approved by the Sarcoma DSG, which comprises medical oncologists, radiation oncologists, surgeons, methodologists, and patient representatives. The results of an external review by Ontario practitioners, obtained through a mailed survey, were incorporated into this report. Final approval of the evidence-based series report was obtained from the Report Approval Panel of Cancer Care Ontario’s Program in Evidence-Based Care (PEBC). Results: The current practice guideline reflects a combination of the draft recommendations (based on the evidence identified in a systematic review and meta-analysis) and the external feedback from Ontario practitioners and the PEBC’s Report Approval Panel. Practice Guideline: In patients with metastatic STS, the addition of ifosfamide to standard first-line doxorubicin-containing regimens is not recommended over single-agent doxorubicin. However, in patients with symptomatic, locally advanced, or inoperable STS, in whom tumour response might potentially result in reduced symptomatology or render a tumour resectable, use of ifosfamide in combination with doxorubicin is reasonable. Qualifying Statement: In combination with a doxorubicin-containing regimen, the dose of ifosfamide should not exceed 7.5 g/m², given as either a split bolus or a continuous infusion.