Hidemasa Kawamura, Presenter: Nothing to Disclose

Takeshi Ebara, Abstract Co-Author: Nothing to Disclose

Hirofumi Shimada, Abstract Co-Author: Nothing to Disclose

Mutsumi Tashiro, Abstract Co-Author: Nothing to Disclose

Tatsuya Ohno MD,PHD, , Abstract Co-Author: Nothing to Disclose

Tatsuaki Kanai, Abstract Co-Author: Nothing to Disclose

Takashi Nakano MD, Abstract Co-Author: Nothing to Disclose

Purpose/Objective(s):To evaluate dosimetric differences between carbon ion radiation therapy (C-RT) and stereotactic body radiotherapy (SBRT) in the treatment of peripheral stage I non-small cell lung cancer.Materials/Methods:The data from 7 stage IA and 6 stage IB consecutive cases of non-small cell lung cancer were analyzed. For comparative planning, each case was planned with C-RT and SBRT using photons. Prescription of the dose and fractionation for stage IA and IB in C-RT were 52.8 GyE/4fr and 60.0 GyE/4fr, respectively and that in SBRT were 52.8 Gy/4fr and 60.0 Gy/4fr, respectively. In C-RT, 2 to 4 beam directions were used, whereas non-coplanar 6 to 10 beam directions were chosen for SBRT. The homogeneity index (HI; maximum dose/minimum dose in target) for GTV and PTV, the conformity index (CI; the volume receiving the minimum target dose/target volume) for the PTV, the mean normal lung dose (MLD), and the relative volumes of normal lung receiving more than a threshold dose (Vdose) were accessed. The normal lung was defined as the both lung minus GTV.Results:The HI for GTV and the CI of C-RT was significantly lower than that of SBRT in both IA and IB. The HI for PTV in both IA and IB were comparable between C-RT and SBRT. Regarding normal lung tissues, the MLD, V5, V10, V15, V20, V25, V30 and V35 of C-RT were significantly lower than that of SBRT for IA. For stage IB, the MLD, V5, V10, V15, V20, V25, V30, V35, V40 and V45 of C-RT were significantly lower than that of SBRT.Conclusions:Compared with SBRT, C-RT has an advantage in both target conformity and sparing of normal lung tissues in peripheral stage I non-small cell lung cancer.

Kawamura, H, Ebara, T, Shimada, H, Tashiro, M, Ohno, T, Kanai, T, Nakano, T, Dosimetric Analysis between Carbon Ion Radiotherapy and Stereotactic Body Radiotherapy in Peripheral Stage I Non-Small Cell Lung Cancer.  Radiological Society of North America 2011 Scientific Assembly and Annual Meeting, November 26 - December 2, 2011 ,Chicago IL. http://archive.rsna.org/2011/11031307.html