' '
Deutsch | English    

Forschungsdatenbank PMU-SQQUID

A dosimetric comparison of IORT techniques in limited-stage breast cancer.
Nairz, O; Deutschmann, H; Kopp, M; Wurstbauer, K; Kametriser, G; Fastner, G; Merz, F; Reitsamer, R; Menzel, C; Sedlmayer, F;
STRAHLENTHER ONKOL. 2006; 182(6): 342-348.
Originalarbeiten (Zeitschrift)

PMU-Autor/inn/en

Deutschmann Heinz
Fastner Gerd
Kopp Michael
Menzel Christian
Reitsamer Roland
Sedlmayer Felix
Wurstbauer Karl

Abstract

Background and Purpose: For intraoperative radiotherapy (IORT) during breast-conserving treatment four different techniques have been addressed: interstitial brachytherapy, an inflatable balloon with a central high-dose-rate source (MammoSite), a miniature orthovolt system (Intrabeam), and Linac-based electron radiotherapy (IOERT). The dosimetric properties of these methods are compared. Material and Methods: Planning target volumes (PTVs) of the same size but of different shapes are assumed, corresponding to the techniquexxxs specific situs. Dose distributions for the PTVs and for surrounding tissues are demonstrated by dose-volume histograms and a List of physical parameters. A dose inhomogeneity index (DII) is introduced to describe the deviation of a delivered from the prescribed dose, reaching its minimal value 0 in case of perfect homogeneity. Results: In terms of DII, IOERT reaches the Lowest value followed by the MammoSite, the Intrabeam and interstitial implants. The surrounding tissues receive the smallest average dose with IOERT, closely followed by the orthovolt system. Conclusion: When comparing simplified geometric figures, IOERT delivers the most homogeneous dose distributions. However, in clinical reality PTVs often present asymmetric shapes instead of ideal geometries. Due to a strictly centric dose fall-off, any system with a round central applicator will have technical Limits. During IOERT margin-directed applicator guidance is possible and interstitial brachytherapy allows for polygonal dose shaping. These techniques seem to be superior for asymmetric PTV irradiation.


Useful keywords (using NLM MeSH Indexing)

Breast Neoplasms/radiotherapy*

Breast Neoplasms/surgery*

Humans

Intraoperative Care/methods*

Mastectomy, Segmental/methods*

Radiometry/methods*

Radiotherapy Dosage

Radiotherapy Planning, Computer-Assisted/methods*

Radiotherapy, Conformal

Reproducibility of Results

Sensitivity and Specificity

Treatment Outcome


Find related publications in this database (Keywords)

breast cancer
intraoperative radiotherapy
IORT
PTV
dosimetry