Sensitivity analysis of tolerance limits for dose escalation

Mark Langer, V. Thai, L. Papiez

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

The potential tradeoff between small relaxations in a dose volume limit and large increases in minimum tumor dose is unavailable in current planning programs. This study shows how the sensitivities to individual limits can be discovered using an optimization program based on combinatorial mathematics. Treatment for a prostate tumor was planned from a set of 36 beams with intensities chosen using a previously described integer program. Tumor dose was maximized for a range of rectal dose volume limits. Changing the volume of rectum that must meet a threshold level of dose produced a more severe effect than changing the threshold dose level for any given volume to protect. A 5% reduction, from 80% to 75%, in the rectal volume that must receive a dose <75 Gy allowed the minimum tumor dose to rise from 76 Gy to 89 Gy, a 17% gain. Making the dose threshold higher or lower than 75 Gy produced only gradual changes in the tumor dose. The sensitive limits were discovered from a three dimensional plot of dose and volume bounds against tumor dose. A large gain in tumor dose can be obtained by changing some limits a small amount. Those limits that affect tumor dose by the greatest amount should be identified, and tolerance studies designed to reduce their uncertainties. By understanding the tradeoffs between tighter limits and lower doses, physicians and patients can choose constraints that best the serve the needs of improving tumor control at an acceptable level of risk.

Original languageEnglish
Title of host publicationAnnual International Conference of the IEEE Engineering in Medicine and Biology - Proceedings
EditorsJ.D. Enderle
Pages698-700
Number of pages3
Volume1
StatePublished - 2000
Event22nd Annual International Conference of the IEEE Engineering in Medicine and Biology Society - Chicago, IL, United States
Duration: Jul 23 2000Jul 28 2000

Other

Other22nd Annual International Conference of the IEEE Engineering in Medicine and Biology Society
CountryUnited States
CityChicago, IL
Period7/23/007/28/00

Fingerprint

Sensitivity analysis
Tumors
Combinatorial mathematics
Planning

Keywords

  • Optimization
  • Sensitivity analysis
  • Tolerance

ASJC Scopus subject areas

  • Bioengineering

Cite this

Langer, M., Thai, V., & Papiez, L. (2000). Sensitivity analysis of tolerance limits for dose escalation. In J. D. Enderle (Ed.), Annual International Conference of the IEEE Engineering in Medicine and Biology - Proceedings (Vol. 1, pp. 698-700)

Sensitivity analysis of tolerance limits for dose escalation. / Langer, Mark; Thai, V.; Papiez, L.

Annual International Conference of the IEEE Engineering in Medicine and Biology - Proceedings. ed. / J.D. Enderle. Vol. 1 2000. p. 698-700.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Langer, M, Thai, V & Papiez, L 2000, Sensitivity analysis of tolerance limits for dose escalation. in JD Enderle (ed.), Annual International Conference of the IEEE Engineering in Medicine and Biology - Proceedings. vol. 1, pp. 698-700, 22nd Annual International Conference of the IEEE Engineering in Medicine and Biology Society, Chicago, IL, United States, 7/23/00.
Langer M, Thai V, Papiez L. Sensitivity analysis of tolerance limits for dose escalation. In Enderle JD, editor, Annual International Conference of the IEEE Engineering in Medicine and Biology - Proceedings. Vol. 1. 2000. p. 698-700
Langer, Mark ; Thai, V. ; Papiez, L. / Sensitivity analysis of tolerance limits for dose escalation. Annual International Conference of the IEEE Engineering in Medicine and Biology - Proceedings. editor / J.D. Enderle. Vol. 1 2000. pp. 698-700
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