A comparison of dosimetric parameters between tomotherapy and three-dimensional conformal radiotherapy in rectal cancer

作者：Yu Mina; Lee Joo Hwan; Jang Hong Seok; Jeon Dong Min; Cheon Jae Suk; Lee Hyo Chun; Lee Jong Hoon

来源：Radiation Oncology, 2013, 8: 181.

DOI：10.1186/1748-717X-8-181

• Conformal
• Dosimetry
• Preoperative radiotherapy
• Rectal cancer
• Tomotherapy

Purpose: Tomotherapy for intensity-modulated radiation has been demonstrated to reduce unnecessary irradiations to adjacent organs at risk (OARs). The purpose of this study was to compare the dosimetric parameters between Tomotherapy and three-dimensional conformal radiotherapy (3D-CRT) in rectal cancer patients. %26lt;br%26gt;Materials and methods: We redesigned three-dimensional conformal plans for 20 rectal cancer patients who had received short-course preoperative radiotherapy with Tomotherapy. The target coverage for 3D-CRT and Tomotherapy was evaluated with the following including the mean dose, V-nGy, D-min, D-max, radiation conformality index (RCI), and radical dose homogeneity index (rDHI). %26lt;br%26gt;Results: The mean PTV dose for Tomotherapy is significantly higher than that observed for the 3D-CRT (p = 0.043). However, there is no significant difference in the V-23.25Gy, V-26.25Gy, V-27.5Gy, and RCI values between Tomotherapy and 3D-CRT. However, the average rDHI (p %26lt; 0.001) value for Tomotherapy was significantly lower than that reported for the 3D-CRT. Tomotherapy significantly lowered the mean level of irradiation doses to the bladder, small bowel, and femur heads as compared to 3D-CRT. %26lt;br%26gt;Conclusions: Tomotherapy could produce a favorable target coverage and significant dose reduction for the OARs at the expense of acceptable dose inhomogeneity of the PTV compared with 3D-CRT in rectal cancer patients.

• 出版日期2013-7-16