Correlation Between Radiation Dose and Molecular Bioluminescence Responses of 4T1 Breast Cancer Cells for Adaptive Radiation Therapy
J Park1*, M Bazalova2, E Graves2, J Lee3, H Park4, C Contag2, T Suh1, (1) The Catholic University of Korea, Seoul, Korea (2) Stanford University, Stanford, CA (3) Konkuk University Medical Center, Seoul, Korea (4) Ajou University School of Medicine, Suwon,KoreaSU-E-J-63 Sunday 3:00PM - 6:00PM Room: Exhibit Hall
Purpose: To determine the required radiation dose and to compensate the dose distribution during the fractionated adaptive radiation therapy, correlation of dose and individual bioluminescence responses of 4T1 breast cancers cells was evaluated using the in-vivo bioluminescence tomography (BLT) images.
Methods:After a dose of 20 Gy in a single fraction was delivered by 200-kV X-ray beams to six female BALB/c mice, radiation responses of the cancer cells were monitored with BLT images in every 2-3 days. The dose distributions on mice were predicted in Monte Carlo simulation using EGSnrc codes (BEAMNRC and DOSXYZNRC). As the bioluminescence distributions were deformed onto the dose maps by applying the vector fields acquired in contour-based rigid and deformable registration, mathematical correlation of dose and bioluminescence was analyzed. The spatial and quantitative bioluminescence variations were also mapped on the computed tomography images to track the proliferation and metastasis characteristics particularly in tumor marginal progression.
Results: Radiation treatment showed the negative correlation between radiation dose and bioluminescence intensity with covariance of up to -0.4. By comparing and categorizing the bioluminescence responses depending on doses in treated and untreated mice group, amount of delivered dose and the field size could be adjusted for more effective control of cancer cells. Spatial tracking of the bioluminescence variations on anatomical coordinates provided useful tool to differentiate the infiltrative cancer cells.
Conclusion:Quantitative BLT images were a useful tool to evaluate dose-related molecular bioluminescence responses of cancer cells of radiation treatment. Required effective doses would be adaptively delivered based on the BLT images according to the radiation treatment scheme and characteristics of the cancer cells.
Funding Support, Disclosures, and Conflict of Interest: This research was supported by Leading Foreign Research Institute Recruitment Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (MEST). (Grant No.2009-00420)