Use of fractional dose-volume histograms to model risk of acute rectal toxicity among patients treated on RTOG 94-06.
Radiother Oncol
; 104(1): 109-13, 2012 Jul.
Article
in En
| MEDLINE
| ID: mdl-22673726
ABSTRACT
BACKGROUND AND PURPOSE:
For toxicities occurring during the course of radiotherapy, it is conceptually inaccurate to perform normal-tissue complication probability analyses using the complete dose-volume histogram. The goal of this study was to analyze acute rectal toxicity using a novel approach in which the fit of the Lyman-Kutcher-Burman (LKB) model is based on the fractional rectal dose-volume histogram (DVH). MATERIALS ANDMETHODS:
Grade ≥2 acute rectal toxicity was analyzed in 509 patients treated on Radiation Therapy Oncology Group (RTOG) protocol 94-06. These patients had no field reductions or treatment-plan revisions during therapy, allowing the fractional rectal DVH to be estimated from the complete rectal DVH based on the total number of dose fractions delivered.RESULTS:
The majority of patients experiencing Grade ≥2 acute rectal toxicity did so before completion of radiotherapy (70/80=88%). Acute rectal toxicity depends on fractional mean rectal dose, with no significant improvement in the LKB model fit when the volume parameter differs from n=1. The incidence of toxicity was significantly lower for patients who received hormone therapy (P=0.024).CONCLUSIONS:
Variations in fractional mean dose explain the differences in incidence of acute rectal toxicity, with no detectable effect seen here for differences in numbers of dose fractions delivered.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Prostatic Neoplasms
/
Rectum
/
Dose Fractionation, Radiation
Type of study:
Etiology_studies
/
Guideline
/
Risk_factors_studies
Limits:
Adult
/
Aged
/
Aged80
/
Humans
/
Male
/
Middle aged
Language:
En
Journal:
Radiother Oncol
Year:
2012
Document type:
Article
Affiliation country: