Primary Outcome Measures:
- Maximum tolerated dose and tolerability of sorafenib tosylate [ Designated as safety issue: Yes ]
- Toxicity according to NCI CTCAE v3.0 [ Designated as safety issue: Yes ]
- Bone toxicity as assessed by volumetric MRI analysis, height and growth measurement, dual-energy x-ray absorptiometry, and laboratory measurements for evaluation of bone turnover and
metabolism [ Designated as safety issue: Yes ]
Secondary Outcome Measures:
- PN growth rate as assessed by automated volumetric MRI analysis [ Designated as safety issue: No ]
- Adherence to chronic daily dosing with sorafenib as assessed by pill counts, adherence diaries and questionnaire forms [ Designated as safety issue: No ]
OBJECTIVES:
Primary
- To determine the maximum tolerated dose (MTD), extended tolerability, and recommended phase II dose of sorafenib tosylate in patients with neurofibromatosis type 1 (NF1) and inoperable plexiform neurofibromas (PN).
- To describe and define the toxicities of chronic dosing with this drug in these patients.
- To evaluate potential bone toxicities, such as growth plate expansion and growth retardation, using automated volumetric MRI analysis, multiple measures for height and growth, dual-energy x-ray absorptiometry for assessment of bone mineral density, and laboratory measurements for assessment of bone turnover and metabolism in these patients.
Secondary
- To determine the effect of this drug on the growth rate of PN in these patients using automated volumetric MRI analysis.
- To measure patient adherence to chronic dosing with this drug.
OUTLINE: This is a multicenter study.
Patients receive oral sorafenib tosylate twice daily on days 1-28. Patients with no documented disease progression or maximum radiographic response within the past 2 years continue treatment for up to 6 months in the absence of disease progression or unacceptable toxicity. All other patients continue treatment for as long as benefit is shown.
After completion of study therapy, patients are followed at 30 days.