Dosimetric evaluation of Tomotherapy and four-box field conformal radiotherapy in locally advanced rectal cancer.
10.3857/roj.2013.31.4.252
- Author:
Mina YU
1
;
Hong Seok JANG
;
Dong Min JEON
;
Geum Seong CHEON
;
Hyo Chun LEE
;
Mi Joo CHUNG
;
Sung Hwan KIM
;
Jong Hoon LEE
Author Information
1. Department of Radiation Oncology, St. Vincent's Hospital, The Catholic University of Korea College of Medicine, Suwon, Korea. koppul@catholic.ac.kr
- Publication Type:Original Article
- Keywords:
Rectal neoplasms;
Helical tomotherapy;
Conformal radiotherapy;
Radiation dosimetry;
Preoperative procedure
- MeSH:
Appointments and Schedules;
Chemoradiotherapy;
Humans;
Organs at Risk;
Pelvis;
Preoperative Care;
Radiometry;
Radiotherapy, Conformal*;
Radiotherapy, Intensity-Modulated;
Rectal Neoplasms*
- From:Radiation Oncology Journal
2013;31(4):252-259
- CountryRepublic of Korea
- Language:English
-
Abstract:
PURPOSE: To report the results of dosimetric comparison between intensity-modulated radiotherapy (IMRT) using Tomotherapy and four-box field conformal radiotherapy (CRT) for pelvic irradiation of locally advanced rectal cancer. MATERIALS AND METHODS: Twelve patients with locally advanced rectal cancer who received a short course preoperative chemoradiotherapy (25 Gy in 5 fractions) on the pelvis using Tomotherapy, between July 2010 and December 2010, were selected. Using their simulation computed tomography scans, Tomotherapy and four-box field CRT plans with the same dose schedule were evaluated, and dosimetric parameters of the two plans were compared. For the comparison of target coverage, we analyzed the mean dose, V(n Gy), D(min), D(max), radical dose homogeneity index (rDHI), and radiation conformity index (RCI). For the comparison of organs at risk (OAR), we analyzed the mean dose. RESULTS: Tomotherapy showed a significantly higher mean target dose than four-box field CRT (p = 0.001). But, V(26.25 Gy) and V(27.5 Gy) were not significantly different between the two modalities. Tomotherapy showed higher D(max) and lower D(min). The Tomotherapy plan had a lower rDHI than four-box field CRT (p = 0.000). Tomotherapy showed better RCI than four-box field CRT (p = 0.007). For OAR, the mean irradiated dose was significantly lower in Tomotherapy than four-box field CRT. CONCLUSION: In locally advanced rectal cancer, Tomotherapy delivers a higher conformal radiation dose to the target and reduces the irradiated dose to OAR than four-box field CRT.