Presented in part at the 54th Annual Meeting of the American Society of Radiation Oncology; October 28-31, 2012, Boston, Massachusetts.
Intensity-modulated radiotherapy (IMRT) in pediatric low-grade glioma
Article first published online: 30 APR 2013
© 2013 American Cancer Society
Volume 119, Issue 14, pages 2654–2659, 15 July 2013
How to Cite
Paulino, A. C., Mazloom, A., Terashima, K., Su, J., Adesina, A. M., Okcu, M. F., Teh, B. S. and Chintagumpala, M. (2013), Intensity-modulated radiotherapy (IMRT) in pediatric low-grade glioma. Cancer, 119: 2654–2659. doi: 10.1002/cncr.28118
- Issue published online: 1 JUL 2013
- Article first published online: 30 APR 2013
- Manuscript Accepted: 11 MAR 2013
- Manuscript Received: 17 FEB 2013
- low grade glioma;
- intensity modulated radiotherapy;
- dose painting
The objective of this study was to evaluate local control and patterns of failure in pediatric patients with low-grade glioma (LGG) who received treatment with intensity-modulated radiation therapy (IMRT).
In total, 39 children received IMRT after incomplete resection or disease progression. Three methods of target delineation were used. The first was to delineate the gross tumor volume (GTV) and add a 1-cm margin to create the clinical target volume (CTV) (Method 1; n = 19). The second was to add a 0.5-cm margin around the GTV to create the CTV (Method 2; n = 6). The prescribed dose to the GTV was the same as dose to the CTV for both Methods 1 and 2 (median, 50.4 grays [Gy]). The final method was dose painting, in which a GTV was delineated with a second target volume (2TV) created by adding 1 cm to the GTV (Method 3; n = 14). Different doses were prescribed to the GTV (median, 50.4 Gy) and the 2TV (median, 41.4 Gy).
The 8-year progression-free and overall survival rates were 78.2% and 93.7%, respectively. Seven failures occurred, all of which were local in the high-dose (≥95%) region of the IMRT field. On multivariate analysis, age ≤5 years at time of IMRT had a detrimental impact on progression-free survival.
IMRT provided local control rates comparable to those provided by 2-dimensional and 3-dimensional radiotherapy. Margins ≥1 cm added to the GTV may not be necessary, because excellent local control was achieved by adding a 0.5-cm margin (Method 2) and by dose painting (Method 3). Cancer 2013;119:2654–2659. © 2013 American Cancer Society.