Safety and efficacy of adjuvant single-agent ifosfamide in uterine sarcoma

The role of adjuvant therapy for completely resected uterine sarcoma continues to be debated. Previous chemotherapy trials have shown little, if any, advantage over surgery alone, with significant added toxicity. To our knowledge, the current study is the first to evaluate adjuvant ifosfamide in completely resected uterine sarcomas.

Between 1992 and 1999, 13 consecutive patients with completely resected moderate- to high-grade uterine sarcoma received three cycles of adjuvant ifosfamide (1.5 g/m(2)/day x 3 days, repeated every 28 days). Mesna was given 30 min prior to infusion. Postinfusion mesna was administered to 10 of the patients in the outpatient setting utilizing a subcutaneous infusion pump. The remaining 3 patients received traditional intravenous mesna at 4 and 8 h after infusion.

The median follow-up of the patient population was 26 months. For early-stage patients (n = 10), the 2-year progression-free survival was 60%, with a median of 26 months. The 2-year overall survival was 100%, dropping to 67% at 3 years. Early-stage patients showed an advantage in both progression-free and overall survival. Early-stage patients with mixed müllerian tumor (MMT) had a significantly longer time to progression that those with leiomyosarcoma (LMS) (2-year progression-free survival of 100% versus 33%; P = 0.019). Three patients required dose reduction secondary to grade 2-3 toxicities (neutropenia x2, nausea and vomiting x1). All significant toxicity was eliminated with dose reduction.

Adjuvant ifosfamide appears to be safe and well tolerated in patients with completely resected uterine sarcoma. It can easily be given in the outpatient setting if mesna is administered via a subcutaneous pump. Our data, consistent with previous studies in advanced sarcoma, suggest a potentially greater role for ifosfamide in MMT than in LMS.