Dosimetric and Efficiency Comparisons between Volumetric Modulated Arc Therapy and IMRT for Cervical-Thoracic Esophageal Cancers ()
Affiliation(s)
1Department of Radiation Oncology, Southern Theater Command Air Force Hospital, Guangzhou, China.
2School of Medical Information and Engineering, Guangdong Pharmaceutical University, Guangzhou, China.
3Department of Radiation Oncology, Nanfang Hospital, Southern Medical University, Guangzhou, China.
4Department of Radiation Oncology, Xiang’an Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, China.
ABSTRACT
Purpose: This study aims to evaluate the treatment plans of Volumetric-modulated arc therapy (VMAT)
and intensity-modulated radiation therapy (IMRT) techniques for cervical-thoracic esophageal cancers. Methods and Materials: Sixty patients were retrospectively identified.
Several parameters were evaluated based on target conformity and
dose-volume histograms of organs at risk (lung, spinal cord, and heart). A
phantom for time comparison was also assessed for each plan. Results: The IMRT plans (5f-IMRT: V95% = 99.4 ±
0.3, 7f-IMRT: V95% = 99.8 ± 0.1) results in better PTV coverage than RA plans
(Single-arc: V95% = 95.8 ± 3.2, Double-arc: V95% = 95.4 ± 2.3). The target dose
conformity of the 5f-IMRT plan was inferior to all plans (CI = 70.4 ± 7.1). The
Single-arc plan achieved the best conformity (CI = 72.5 ± 4.6), whereas the
Double-arc plan (CI = 72.1 ± 5.1) was slightly inferior to the Single-arc plan
but superior to the 7f-IMRT plan (CI = 71.7 ± 8.6). The total MU was reduced by 42.1% in VMAT plan. The average MU
needed to deliver the dose of 60 Gy for Single-arc (423.5 ± 52.1 MU) was found
to be the least. Similarly, the average MU for the 5f-IMRT, 7f-IMRT and
Double-arc were 868.2 ± 182.0 MU, 870.0 ± 225.3 MU and 548.8 ± 47.2 MU,
respectively. The delivery time in VMAT plans was reduced
from 193.8 seconds to 99.2 seconds by
around 48.8% compared to IMRT plans. Conclusion: For similar PTV parameters, VMAT delivers a
lower dose to organs at risk than IMRT in a shorter time, and this has
warranted clinical implementation.
Share and Cite:
Duan, Y. , Liu, X. , Liu, Z. , Zhan, N. , Zhu, Z. and Deng, Z. (2021) Dosimetric and Efficiency Comparisons between Volumetric Modulated Arc Therapy and IMRT for Cervical-Thoracic Esophageal Cancers.
Journal of Cancer Therapy,
12, 593-601. doi:
10.4236/jct.2021.1211051.