Volumetric Modulated Arc Therapy (VMAT) Reduces Treatment Time and Improves Dosimetry Compared to Conventional Intensity Modulated Radiotherapy (IMRT) for Frontal and Temporal High-grade Gliomas (HGG)

Purpose. Spine stereotactic radiosurgery (SRS) delivers an accurate and efficient high radiation dose to vertebral metastases in 1–5 fractions. We aimed to compare volumetric modulated arc therapy (VMAT) to static beam intensity modulated radiotherapy (IMRT) for spine SRS.Methods and Materials. Ten spine lesions of previously treated SRS patients were planned retrospectively using both IMRT and VMAT with a prescribed dose of 16 Gy to 100% of the planning target volume (PTV). The plans were compared for conformity, homogeneity, treatment delivery time, and safety (spinal cord dose).Results. All evaluated parameters favored the VMAT plan over the IMRT plans.Dminin the IMRT was significantly lower than in the VMAT plan (7.65 Gy/10.88 Gy,p<0.001), the Dice Similarity Coefficient (DSC) was found to be significantly better for the VMAT plans compared to the IMRT plans (0.77/0.58, resp.,p value<0.01), and an almost 50% reduction in the net treatment time was calculated for the VMAT compared to the IMRT plans (6.73 min/12.96 min,p<0.001).Conclusions. In our report, VMAT provides better conformity, homogeneity, and safety profile. The shorter treatment time is a major advantage and not only provides convenience to the painful patient but also contributes to the precision of this high dose radiation therapy.

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Volumetric Modulated Arc Radiotherapy for Early Stage Non-Small-Cell Lung Carcinoma: Is It Better Than the Conventional Static Beam Intensity Modulated Radiotherapy?

Journal of Radiotherapy ◽

10.1155/2014/164165 ◽

2014 ◽

Vol 2014 ◽

pp. 1-5

Author(s):

Vincent Wing Cheung Wu ◽

Man In Pun ◽

Cho Pan Lam ◽

To Wing Mok ◽

Wah Wai Mok

Keyword(s):

Early Stage ◽

Small Cell Lung Carcinoma ◽

Volumetric Modulated Arc Therapy ◽

Intensity Modulated Radiotherapy ◽

Small Cell ◽

Small Cell Lung ◽

Cell Lung Carcinoma ◽

Intensity Modulated ◽

Significant Difference ◽

Arc Therapy

This study compared the performance of volumetric modulated arc therapy (VMAT) techniques: single arc volumetric modulated arc therapy (SA-VMAT) and double arc volumetric modulated arc therapy (DA-VMAT) with the static beam conventional intensity modulated radiotherapy (C-IMRT) for non-small-cell lung carcinoma (NSCLC). Twelve stage I and II NSCLC patients were recruited and their planning CT with contoured planning target volume (PTV) and organs at risk (OARs) was used for planning. Using the same dose constraints and planning objectives, the C-IMRT, SA-VMAT, and DA-VMAT plans were optimized. C-IMRT consisted of 7 static beams, while SA-VMAT and DA-VMAT plans consisted of one and two full gantry rotations, respectively. No significant difference was found among the three techniques in target homogeneity and conformity. Mean lung dose in C-IMRT plan was significantly lower than that in DA-VMAT plan P=0.04. The ability of OAR sparing was similar among the three techniques, with no significant difference in V20, V10, or V5 of normal lungs, spinal cord, and heart. Less MUs were required in SA-VMAT and DA-VMAT. Besides, SA-VMAT required the shortest beam on time among the three techniques. In treatment of early stage NSCLC, no significant dosimetric superiority was shown by the VMAT techniques over C-IMRT and DA-VMAT over SA-VMAT.

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