Clinical radiation doses for spinal cord: the 1998 international questionnaire

Background and purpose: Emmanuel van der Schueren gave a keynote lecture at the 1988 ASTRO annual conference pointing out that the spinal cord 'tolerance doses' then prescribed were probably unnecessarily cautious. resulting in probable underdosing of some tumours. This lecture was supported both by an international questionnaire which he and two of the present authors had conducted, and by animal experimental data. In 1997 he initiated a 10-year follow-up questionnaire, the results of which are summarised here. Materials and methods: The present report analyses the change in prescriptions fi om 1988 to 1998 and the variation in prescriptions among various regions of the World. Results and conclusions: The main conclusion is that pl escribed dose levels have increased significantly in this period. Large geographical variations still exist. Among responders who use a formula to correct for changed dose per fraction, 90% are now using the linear-quadratic model vs. 33% in 1988. The current status of clinically acceptable doses to spinal cord in 2-Gy fractions is discussed briefly. Further details from the responses to the 1998 questionnaire will be presented in another publication. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved.