Published in:
01-12-2020 | Radiotherapy | Original Research
Dosimetric comparison of three-dimensional conformal radiotherapy and static and dynamic intensity-modulated radiotherapy for the treatment of early-stage glottic cancer
Published in: Journal of Radiation Oncology | Issue 3-4/2020
Login to get accessAbstract
Background
The aim of this study was to compare dosimetric variations using the three-dimensional conformal radiotherapy (3DCRT), dynamic intensity-modulated radiation therapy (D-IMRT), and static intensity-modulated radiation therapy (S-IMRT) techniques for glottic cancer.
Materials and methods
Ten patients with early-stage glottic cancer were retrospectively selected and evaluated. The 3DCRT and IMRT treatment plans were performed using the solution commercialized by Varian with the Eclipse treatment planning system (TPS). For each patient, five different treatment plans were created and compared with respect to the doses received by the organs at risk (OARs) including the carotid arteries, thyroid gland, and spinal cord; the dose homogeneity index (DHI); conformity indexes (CI); and total monitor unit (MU) counts required for the treatment. The Mann-Whitney U test was used for statistical analyses.
Results
Statistically significant differences for the 3DCRT, D-IMRT, and S-IMRT techniques were observed for the planning target volume (PTV) mean and maximum doses. The results of this study indicated an increase in DHI for 3DCRT compared with D-IMRT and S-IMRT. Furthermore, the S-IMRT technique led to the superior decreased dose to the OAR. The 3DCRT plans performed better at the Dmax of the spinal cord and MU counts.
Conclusion
The D-IMRT and S-IMRT techniques allowed more homogeneous dose distributions in PTV. Considering the dose to OAR, S-IMRT was more appropriate rather than 3DCRT and D-IMRT.