IMRT: Another Point of View

S. Jack Wei, MD
Abramson Cancer Center of the University of Pennsylvania
Last Modified: October 22, 2003

Moderator: Theodore L. Phillips, MD., University of California, San Francisco

Edward C. Halperin, MD, Duke University

  • There is a difference between research and therapy.
  • As a field, we have used research and randomized trials selectively if they show a benefit for radiation, but have dismissed its necessity when we do not have the data.
  • There have been a number of cases where early results from non-randomized data compared to historic controls appeared to show a benefit, but did not show a benefit after randomized testing. Examples include bone marrow transplant for breast cancer, beta-carotene for decreasing cancer incidence, hyperfractionated radiation for pediatric brain stem tumors, etc.
  • Non-randomized data compared to historic controls is not equal to randomized data.
  • The increased treatment time and monitor units due to IMRT result in higher leakage and scatter as is evidenced by the increased rate of second neoplasms with IMRT (1% vs. 1.75% at 10 years).
  • We must not confuse differential dose distributions with differential outcomes.
  • IMRT should be viewed as research, not therapy.