Effect of heterogeneity correction on dosimetric parameters of radiotherapy planning for thoracic esophageal cancer.
Med Dosim
; 39(1): 31-3, 2014.
Article
in En
| MEDLINE
| ID: mdl-24200673
ABSTRACT
The present study aimed to investigate the effect of heterogeneity correction (HC) on dosimetric parameters in 3-dimensional conformal radiotherapy planning for patients with thoracic esophageal cancer. We retrospectively analyzed 20 patients. Two treatment plans were generated for each patient using a superposition algorithm on the Xio radiotherapy planning system. The first plan was calculated without HC. The second was a new plan calculated with HC, using identical beam geometries and maintaining the same number of monitor units as the first. With regard to the planning target volume (PTV), the overall mean differences in the prescription dose, maximum dose, mean dose, and dose that covers 95% of the PTV between the first and second plans were 1.10Gy (1.8%), 1.35Gy (2.2%), 1.10Gy (1.9%), and 0.56Gy (1.0%), respectively. With regard to parameters related to the organs at risk (OARs), the mean differences in the absolute percentages of lung volume receiving greater than 5, 10, 20, and 30Gy (lung V5, V10, V20, and V30) between the first and second plans were 7.1%, 2.7%, 0.4%, and 0.5%, respectively. These results suggest that HC might have a more pronounced effect on the percentages of lung volume receiving lower doses (e.g., V5 and V10) than on the dosimetric parameters related to the PTV and other OARs.
Key words
Full text:
1
Database:
MEDLINE
Main subject:
Thoracic Neoplasms
/
Algorithms
/
Radiotherapy Planning, Computer-Assisted
/
Esophageal Neoplasms
/
Artifacts
Type of study:
Diagnostic_studies
/
Observational_studies
/
Risk_factors_studies
Limits:
Humans
Language:
En
Journal:
Med Dosim
Journal subject:
RADIOTERAPIA
Year:
2014
Type:
Article