Skip to main content
Journal cover image

Monte Carlo-based dosimetry of head-and-neck patients treated with SIB-IMRT.

Publication ,  Journal Article
Sakthi, N; Keall, P; Mihaylov, I; Wu, Q; Wu, Y; Williamson, JF; Schmidt-Ullrich, R; Siebers, JV
Published in: Int J Radiat Oncol Biol Phys
March 1, 2006

PURPOSE: To evaluate the accuracy of previously reported superposition/convolution (SC) dosimetric results by comparing with Monte Carlo (MC) dose calculations for head-and-neck intensity-modulated radiation therapy (IMRT) patients treated with the simultaneous integrated boost technique. METHODS AND MATERIALS: Thirty-one plans from 24 patients previously treated on a phase I/II head-and-neck squamous cell carcinoma simultaneous integrated boost IMRT protocol were used. Clinical dose distributions, computed with an SC algorithm, were recomputed using an EGS4-based MC algorithm. Phantom-based dosimetry quantified the fluence prediction accuracy of each algorithm. Dose-volume indices were used to compare patient dose distributions. RESULTS AND DISCUSSION: The MC algorithm predicts flat-phantom measurements better than the SC algorithm. Average patient dose indices agreed within 2.5% of the local dose for targets; 5.0% for parotids; and 1.9% for cord and brainstem. However, only 1 of 31 plans agreed within 3% for all indices; 4 of 31 agreed within 5%. In terms of the prescription dose, 4 of 31 plans agreed within 3% for all indices, whereas 28 of 31 agreed within 5%. CONCLUSIONS: Average SC-computed doses agreed with MC results in the patient geometry; however deviations >5% were common. The fluence modulation prediction is likely the major source of the dose discrepancy. The observed dose deviations can impact dose escalation protocols, because they would result in shifting patients to higher dose levels.

Duke Scholars

Published In

Int J Radiat Oncol Biol Phys

DOI

ISSN

0360-3016

Publication Date

March 1, 2006

Volume

64

Issue

3

Start / End Page

968 / 977

Location

United States

Related Subject Headings

  • Radiotherapy, Intensity-Modulated
  • Radiotherapy Dosage
  • Oncology & Carcinogenesis
  • Monte Carlo Method
  • Humans
  • Head and Neck Neoplasms
  • Carcinoma, Squamous Cell
  • Algorithms
  • 5105 Medical and biological physics
  • 3407 Theoretical and computational chemistry
 

Citation

APA
Chicago
ICMJE
MLA
NLM
Sakthi, N., Keall, P., Mihaylov, I., Wu, Q., Wu, Y., Williamson, J. F., … Siebers, J. V. (2006). Monte Carlo-based dosimetry of head-and-neck patients treated with SIB-IMRT. Int J Radiat Oncol Biol Phys, 64(3), 968–977. https://doi.org/10.1016/j.ijrobp.2005.09.049
Sakthi, Nirmal, Paul Keall, Ivaylo Mihaylov, Qiuwen Wu, Yan Wu, Jeffrey F. Williamson, Rupert Schmidt-Ullrich, and Jeffrey V. Siebers. “Monte Carlo-based dosimetry of head-and-neck patients treated with SIB-IMRT.Int J Radiat Oncol Biol Phys 64, no. 3 (March 1, 2006): 968–77. https://doi.org/10.1016/j.ijrobp.2005.09.049.
Sakthi N, Keall P, Mihaylov I, Wu Q, Wu Y, Williamson JF, et al. Monte Carlo-based dosimetry of head-and-neck patients treated with SIB-IMRT. Int J Radiat Oncol Biol Phys. 2006 Mar 1;64(3):968–77.
Sakthi, Nirmal, et al. “Monte Carlo-based dosimetry of head-and-neck patients treated with SIB-IMRT.Int J Radiat Oncol Biol Phys, vol. 64, no. 3, Mar. 2006, pp. 968–77. Pubmed, doi:10.1016/j.ijrobp.2005.09.049.
Sakthi N, Keall P, Mihaylov I, Wu Q, Wu Y, Williamson JF, Schmidt-Ullrich R, Siebers JV. Monte Carlo-based dosimetry of head-and-neck patients treated with SIB-IMRT. Int J Radiat Oncol Biol Phys. 2006 Mar 1;64(3):968–977.
Journal cover image

Published In

Int J Radiat Oncol Biol Phys

DOI

ISSN

0360-3016

Publication Date

March 1, 2006

Volume

64

Issue

3

Start / End Page

968 / 977

Location

United States

Related Subject Headings

  • Radiotherapy, Intensity-Modulated
  • Radiotherapy Dosage
  • Oncology & Carcinogenesis
  • Monte Carlo Method
  • Humans
  • Head and Neck Neoplasms
  • Carcinoma, Squamous Cell
  • Algorithms
  • 5105 Medical and biological physics
  • 3407 Theoretical and computational chemistry