Intensity-modulated radiotherapy for head-and-neck rhabdomyosarcoma.

Abstract

To determine the preliminary results of intensity-modulated radiotherapy (IMRT) for head-and-neck rhabdomyosarcoma. Twenty-eight patients underwent IMRT as a part of multimodality therapy. Twenty-one tumors were parameningeal, three were orbital, and four were in other sites. The median age was 8 years (range, 1-29 years). Most (89%) had Group III disease. Intracranial extension was present in 71% of parameningeal tumors. A 1.5-cm margin was used, and the median dose was 50.4 Gy (range, 30-55.8 Gy). The actuarial 3-year survival rate for patients with parameningeal tumors was 65%. The 3-year actuarial freedom from failure rate was 95% locally, 90% in regional nodes, 88% in the central nervous system, and 80% at distant sites. No failures occurred among patients with orbit tumors; a single central nervous system failure occurred in 1 patient with a lip/cheek tumor. Disease-free survival was significantly worse for patients with alveolar histologic features (p = 0.01). Acute radiation toxicity was similar to that reported by the Intergroup Rhabdomyosarcoma Study Group. Late radiation toxicity was recorded and was mild. IMRT with image fusion results in outstanding local control despite the use of a reduced margin. However, survival among patients with alveolar histologic findings or intracranial extension remains unacceptably low.