Dosimetric comparison of volumetric modulated arc therapy with robotic stereotactic radiation therapy in hepatocellular carcinoma.

Eun Kyung Paik; Mi-Sook Kim; Chul Won Choi; Won Il Jang; Sung Hyun Lee; Sang Hyoun Choi; Kum Bae Kim; Dong Han Lee

Purpose: To compare volumetric modulated arc therapy of RapidArc with robotic stereotactic body radiation therapy (SBRT) of CyberKnife in the planning and delivery of SBRT for hepatocellular carcinoma (HCC) treatment by analyzing dosimetric parameters. Materials and Methods: Two radiation treatment plans were generated for 29 HCC patients, one using Eclipse for the RapidArc plan and the other using Multiplan for the CyberKnife plan. The prescription dose was 60 Gy in 3 fractions. The dosimetric parameters of planning target volume (PTV) coverage and normal tissue sparing in the RapidArc and the CyberKnife plans were analyzed. Results: The conformity index was 1.05 ± 0.02 for the CyberKnife plan, and 1.13 ± 0.10 for the RapidArc plan. The homogeneity index was 1.23 ± 0.01 for the CyberKnife plan, and 1.10 ± 0.03 for the RapidArc plan. For the normal liver, there were significant differences between the two plans in the low-dose regions of V1 and V3. The normalized volumes of V60 for the normal liver in the RapidArc plan were drastically increased when the mean dose of the PTVs in RapidArc plan is equivalent to the mean dose of the PTVs in the CyberKnife plan. Conclusion: CyberKnife plans show greater dose conformity, especially in small-sized tumors, while RapidArc plans show good dosimetric distribution of low dose sparing in the normal liver and body.

LIVER cancer; CANCER treatment; STEREOTACTIC radiotherapy; RADIATION dosimetry; CANCER research

Radiation Oncology Journal, 2015, Vol 33, Issue 3, p233

2234-1900

Academic Journal

10.3857/roj.2015.33.3.233