Ayşe Nur DEMİRAL, Ayşegül YURT, Nuri KARABAY, Barbaros AYDIN, Sevecen Seyhun NASİR, Cenk UMAY

Correlation Between CT-Simulator and Dynamic Magnetic Resonance Images in Determining The Location of Gross Tumor Volume in Radiotherapy Treatment Planning for Lung Cancer

Objective: This study aimed to determine the accuracy of the average tumor location in CT-simulator images and PTV margins in radiotherapytreatment planning by detecting lung tumor mobility in dynamic MRI scans of patients presenting with lung cancer.Materials and Method: Dynamic MRI examination was performed in 12 lung cancer patients scheduled for 3-dimensional conformal RT(3D-CRT) using CT-simulator. In this study, maximum tumor displacement (CC-MRI, ML-MRI, AP-MRI) was measured that occurred in CC,AP and ML axes in expiratory and inspiratory phases of dynamic MRI. The distance from the upper limit of GTV to the reference line (CC-CT)was measured in CT-simulator images. CC-CT and CCmean-MRI values were compared with the Wilcoxon signed-rank test. Furthermore,correlation of these values was evaluated with Spearman’s correlation test.Results: In comparison of CC-CT and CCmean-MRI values, no statistically significant difference was detected between CT-simulator anddynamic MRI modalities (p=0.172). In addition, a high level of correlation was found between these two imaging methods (p

PDF

___

1. Heelan RT, Demas BE, Carevelli JF, et al. Superior sulcus tumors: CT and MR imaging. Radiology 1989;170:637–641. [CrossRef]
2. Pauls S, Breining T, Muche R, et al. The role of dynamic, contrastenhanced MRI in differentiating lung tumor subtypes. Clin Imaging 2011;35:259–265. [CrossRef]
3. Kramer H, Groen HJM. Current concepts in the mediastinal lymph node staging of nonsmall cell lung cancer. Ann Surg 2003;238:180– 188. [CrossRef]
4. Tavlayan E. The effect of CT and MRI image registration on target volume determination and dose distribution in the radiotherapy planning of brain tumors. Master of Science Thesis. İzmir; 2006. pp.1–6.
5. Shimizu S, Shirato H, Kagei K, et al. Impact of respiratory movement on the computed tomographic images of small lung tumors in three-dimensional (3D) radiotherapy. Int J Radiat Oncol Biol Phys 2000;46:1127–1133. [CrossRef]
6. Stevens CW, Munden RF, Forster KM, et al. Respiratory-driven lung tumor motion in depend of tumor size, tumor location, and pulmonary function. Int J Radiat Oncol Biol Phys 2001;51:62–68. [CrossRef]
7. Gierada DS, Curtin JJ, Erickson SJ, Prost RW, Strandt JA, Goodman LR. Diaphragmatic motion: fast gradient-recalled-echo MR imaging in healthy subjects. Radiology 1995;194:879–884. [CrossRef]
8. Napadow VJ, Mai V, Bankier A, Gilbert RJ, Edelman R, Chen Q. Determination of regional pulmonary parenchymal strain during normal respiration using spin inversion tagged magnetization MRI. J Magn Reson Imaging 2001;13:467–474. [CrossRef]
9. Plathow C, Fink C, Ley S, et al. Measurement of tumor diameterdependent mobility of lung tumors by dynamic MRI. Radiother Oncol 2004;73:349–354. [CrossRef]
10. Harada T, Shirato H, Ogura S, et al. Real-time tumor-tracking radiation therapy for lung carcinoma by the aid of insertion of a gold marker using bronchofiberscopy. Cancer 2002;95:1720–1727. [CrossRef]
11. Wong JW, Sharpe MB, Jaffray DA, et al. The use of active breathing control (ABC) to reduce margin for breathing motion. Int J Radiat Oncol Biol Phys 1999;44:911–919. [CrossRef]
12. Lohr F, Debus J, Frank C, et al. Noninvasive patient fixation for extracranial stereotactic radiotherapy. Int J Radiat Oncol Biol Phys 1999;45:521–527. [CrossRef]
13. Ohara K, Okumura T, Akisada M, et al. Irradiation synchronized with respiration gate. Int J Radiat Oncol Biol Phys 1989;17:853–857. [CrossRef]
14. Kubo HD, Hill BC. Respiration gated radiotherapy treatment: a technical study. Phys Med Biol 1996;41:83–91. [CrossRef]
15. Shimizu S, Shirato H, Aoyama H, et al. High-speed magnetic resonance imaging for four-dimensional treatment planning of conformal radiotherapy of moving body tumors. Int J Radiat Oncol Biol Phys 2000;48:471–474. [CrossRef]
16. Lagerwaard FJ, Van Sornsen de Koste JR, Nijssen-Visser MR, et al. Multiple slow CT scans for incorporating lung tumor mobility in radiotherapy planning. Int J Radiat Oncol Biol Phys 2001;51:932–937. [CrossRef]
17. Hof H, Herfarth KK, Münter M, Essig M, Wannenmacher M, Debus J. The use of the multislice CT for the determination of respiratory lung tumor movement in stereotactic single-dose irradiation. Strahlenther Onkol 2003;8:542–547. [CrossRef]
18. Kovacs A, Hadjiev J, Lakosi F, et al. Dynamic MR Based Analysis of Tumor Movement in Upper and Mid Lobe Localized Lung Cancer. Pathol Oncol Res 2009;15:269–277. [CrossRef]