High-dose ifosfamide with mesna and granulocyte-colony-stimulating factor (recombinant human G-CSF) in patients with unresectable malignant mesothelioma

BACKGROUND: The current study was conducted to assess the activity and toxicity of high-dose ifosfamide and mesna with recombinant human granulocyte-colony-stimulating factor (rhG-CSF), given in an outpatient setting, in the treatment of patients with unresectable malignant mesothelioma. METHODS: Between September 1994 and September 1996, 41 patients with histologically verified, unresectable malignant mesothelioma were registered, 38 of whom were analyzable (2 were ineligible and 1 was nonanalyzable). Patients received intravenous ifosfamide at a dose of 2.8 g/m2 over 3 hours (total dose of 14 g/m2), plus mesna at a dose of 0.56 g/m2 prior to and at 4 hours and 8 hours after ifosfamide infusion daily for 5 days every 21 days. rhG-CSF at a dose of 5 microg/kg/day was administered subcutaneously on days 6-15. RESULTS: Response assessment could be determined adequately in 21 patients. Two patients obtained responses; 1 was a confirmed partial response (3%; 95% confidence interval 95% CI], 0-14%) and 1 was an unconfirmed response (3%; 95% CI, 5-14%). Eleven patients had stable disease (29%), 7 patients developed disease progression (18%), 1 patient had an early death (3%), and 17 patients had inadequate assessment (45%). At the time of last follow-up, 36 of the 38 eligible patients had developed disease progression, with a median progression-free survival of 5 months (95% CI, 3-7 months) and 34 patients had died with a median survival of 7 months (95% CI, 6-9 months). Twenty-four patients (63%) and 7 patients (18%), respectively, had Grade (according to Southwestern Oncology Group Toxicity Criteria) 4 hematologic toxicities and Grade 4 nonhematological toxicities. There was one treatment-related death, the result of infection, pulmonary edema, and renal failure. CONCLUSIONS: This regimen demonstrated a low overall objective response rate with substantial toxicity, and in the opinion of the authors does not warrant further investigation in the treatment of patients with unresectable malignant mesothelioma.