@misc{oai:repo.qst.go.jp:00066777,
 author = {今井, 礼子 and 今井 礼子},
 month = {Apr},
 note = {Abstract
Background and purpose: Since 1996 carbon ion radiotherapy (C-ion RT) for unresectable sarcomas has been organized and treated cases have been accumulated. The most major sarcoma treated with C-ion RT was sacral chordoma. This study aimed for investigating that the findings of MRI images at the time of local recurrence and those after re-irradiation predict prognosis.
Material and Methods: Between 1996 and 2013, 188 sacral chordomas without prior surgery were treated with C-ion RT. Among 188 cases, 41 had local recurrence. We measured: A) the ratio of the lowest value in the recurrent tumor and the value in the muscle on T2WI images (A). B) the lowest value of recurrent tumor on the DWI images (B). We evaluated the correlation between A, B and survival after re- C-ion RT and between A, B and local control after re- C-ion RT.
Results: Among 41 local recurrent cases 20 cases received re-C ion RT and assessed. The MRI images taken 6-12 months after C-ion RT was evaluated.
Using t-test, B had a significe between the local recurrence cases and the local control cases. Between A>6.5 and <6.5, 3-year overall survival rate at 88% and 49%, respectively had a significance. 
Conclusion: The ratio of the lowest values in the recurrent tumor and in the 
muscle on T2WI images, and the lowest value of recurrent tumor on the DWI images could predict the prognosis after recurrence and after re-C-ion RT., H29年度HIMAC共同利用研究成果発表会},
 title = {仙骨脊索腫重粒子線治療後、局所再発症例のMRI画像の検討},
 year = {2018}
}