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Title: Estimating differences in volumetric flat bone growth in pediatric patients by radiation treatment method

Abstract

Purpose: To estimate potential differences in volumetric bone growth in children with sarcoma treated with intensity-modulated (IMRT) and conformal (CRT) radiation therapy using an empiric dose-effect model. Methods and Materials: A random coefficient model was used to estimate potential volumetric bone growth of 36 pelvic bones (ischiopubis and ilium) from 11 patients 4 years after radiotherapy. The model incorporated patient age, pretreatment bone volume, integral dose >35 Gy, and time since completion of radiation therapy. Three dosimetry plans were entered into the model: the actual CRT/IMRT plan, a nontreated comparable IMRT/CRT plan, and an idealized plan in which dose was delivered only to the planning target volume. The results were compared with modeled normal bone growth. Results: The model predicted that by using the idealized, IMRT, and CRT approaches, patients would maintain 93%, 87%, and 84%, respectively (p = 0.06), of their expected normal growth. Patients older than 10 years would maintain 98% of normal growth, regardless of treatment method. Those younger than 10 years would maintain 87% (idealized), 76% (IMRT), or 70% (CRT) of their expected growth (p = 0.015). Post hoc testing (Tukey) revealed that the CRT and IMRT approaches differed significantly from the idealized one but notmore » from each other. Conclusions: Dose-effect models facilitate the comparison of treatment methods and potential interventions. Although treatment methods do not alter the growth of flat bones in older pediatric patients, they may significantly impact bone growth in children younger than age 10 years, especially as we move toward techniques with high conformity and sharper dose gradient.« less

Authors:
 [1];  [2];  [3];  [3]
  1. Division of Radiation Oncology, Department of Radiological Sciences, St Jude Children's Research Hospital, Memphis, TN (United States). E-mail: Chia-Ho.Hua@stjude.org
  2. Department of Radiation Oncology, University of Iowa, Iowa City, IA (United States)
  3. Division of Radiation Oncology, Department of Radiological Sciences, St Jude Children's Research Hospital, Memphis, TN (United States)
Publication Date:
OSTI Identifier:
20944701
Resource Type:
Journal Article
Resource Relation:
Journal Name: International Journal of Radiation Oncology, Biology and Physics; Journal Volume: 67; Journal Issue: 2; Other Information: DOI: 10.1016/j.ijrobp.2006.08.069; PII: S0360-3016(06)02830-6; Copyright (c) 2007 Elsevier Science B.V., Amsterdam, Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
62 RADIOLOGY AND NUCLEAR MEDICINE; ANIMAL GROWTH; CHILDREN; DOSIMETRY; INTEGRAL DOSES; PATIENTS; PEDIATRICS; RADIOTHERAPY; SARCOMAS; SKELETON; TESTING

Citation Formats

Hua Chiaho, Shukla, Hemant I., Merchant, Thomas E., and Krasin, Matthew J. Estimating differences in volumetric flat bone growth in pediatric patients by radiation treatment method. United States: N. p., 2007. Web.
Hua Chiaho, Shukla, Hemant I., Merchant, Thomas E., & Krasin, Matthew J. Estimating differences in volumetric flat bone growth in pediatric patients by radiation treatment method. United States.
Hua Chiaho, Shukla, Hemant I., Merchant, Thomas E., and Krasin, Matthew J. Thu . "Estimating differences in volumetric flat bone growth in pediatric patients by radiation treatment method". United States. doi:.
@article{osti_20944701,
title = {Estimating differences in volumetric flat bone growth in pediatric patients by radiation treatment method},
author = {Hua Chiaho and Shukla, Hemant I. and Merchant, Thomas E. and Krasin, Matthew J.},
abstractNote = {Purpose: To estimate potential differences in volumetric bone growth in children with sarcoma treated with intensity-modulated (IMRT) and conformal (CRT) radiation therapy using an empiric dose-effect model. Methods and Materials: A random coefficient model was used to estimate potential volumetric bone growth of 36 pelvic bones (ischiopubis and ilium) from 11 patients 4 years after radiotherapy. The model incorporated patient age, pretreatment bone volume, integral dose >35 Gy, and time since completion of radiation therapy. Three dosimetry plans were entered into the model: the actual CRT/IMRT plan, a nontreated comparable IMRT/CRT plan, and an idealized plan in which dose was delivered only to the planning target volume. The results were compared with modeled normal bone growth. Results: The model predicted that by using the idealized, IMRT, and CRT approaches, patients would maintain 93%, 87%, and 84%, respectively (p = 0.06), of their expected normal growth. Patients older than 10 years would maintain 98% of normal growth, regardless of treatment method. Those younger than 10 years would maintain 87% (idealized), 76% (IMRT), or 70% (CRT) of their expected growth (p = 0.015). Post hoc testing (Tukey) revealed that the CRT and IMRT approaches differed significantly from the idealized one but not from each other. Conclusions: Dose-effect models facilitate the comparison of treatment methods and potential interventions. Although treatment methods do not alter the growth of flat bones in older pediatric patients, they may significantly impact bone growth in children younger than age 10 years, especially as we move toward techniques with high conformity and sharper dose gradient.},
doi = {},
journal = {International Journal of Radiation Oncology, Biology and Physics},
number = 2,
volume = 67,
place = {United States},
year = {Thu Feb 01 00:00:00 EST 2007},
month = {Thu Feb 01 00:00:00 EST 2007}
}
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