Caution on the use of altered fractionation for nasopharyngeal carcinoma.

Randomized trials and overviews on the value of altered fractionation for head and neck cancers are reviewed. Attention is drawn to the unexpectedly high incidence of temporal lobe necrosis incurred in patients with nasopharyngeal carcinoma. Preliminary analyses suggest that incomplete repair is likely to be the major factor, even a 6-h interfraction interval may be inadequate if substantial volumes of nervous tissues are included within the target volume.