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

Area of Science:

• Oncology
• Medical Chemotherapy
• Osteosarcoma Research

Background:

• Effectiveness of second-line palliative chemotherapy for recurrent/metastatic osteosarcoma remains unclear.
• Limited data exists from small studies on ifosfamide as a second-line treatment.
• This study details single-center experience with ifosfamide monotherapy in this patient group.

Purpose of the Study:

• To evaluate the effectiveness of second-line ifosfamide monotherapy in patients with recurrent/metastatic osteosarcoma.
• To compare outcomes between different ifosfamide dosage regimens (5 g/m² vs. 9 g/m²).
• To assess the impact of performance status on survival.

Main Methods:

• Retrospective chart review of osteosarcoma patients treated with ifosfamide (1978-2017).
• Analysis of overall survival (OS) and progression-free survival (PFS).
• Statistical analysis including log-rank test and Cox proportional hazard regression.

Main Results:

• Sixty-two patients received second-line ifosfamide (26 at 5 g/m², 36 at 9 g/m²).
• Univariate analysis showed better OS with 9 g/m² ifosfamide and better performance status (PS).
• Multivariate analysis indicated PS as the only significant factor affecting OS; no PFS difference was observed.

Conclusions:

• Ifosfamide monotherapy is an effective second-line treatment option for recurrent/metastatic osteosarcoma.
• Patient's performance status is a critical determinant of overall survival.
• This study provides a benchmark for future phase II trials in osteosarcoma treatment.