Ryo Toya1, Tetsuo Saito2, Shinya Shiraishi3, Yudai Kai4, Ryuji Murakami5, Tomohiko Matsuyama2, Takahiro Watakabe2, Fumi Sakamoto3, Noriko Tsuda3, Yoshinobu Shimohigashi4, Yasuyuki Yamashita3, Natsuo Oya2. 1. Department of Radiation Oncology, Kumamoto University Hospital, Kumamoto University, Kumamoto, Japan ryo108@kumamoto-u.ac.jp. 2. Department of Radiation Oncology, Kumamoto University Hospital, Kumamoto University, Kumamoto, Japan. 3. Department of Diagnostic Radiology, Kumamoto University Hospital, Kumamoto University, Kumamoto, Japan. 4. Department of Radiological Technology, Kumamoto University Hospital, Kumamoto University, Kumamoto, Japan. 5. Department of Medical Imaging, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan.
Abstract
BACKGROUND/AIM: We evaluated the influence of previous treatments on the parametric discrepancies between dose-volume histograms (DVHs) and dose-function histograms (DFHs) generated based on 99mTc-GSA SPECT images of hepatocellular carcinoma (HCC) patients treated with stereotactic body radiation therapy (SBRT). PATIENTS AND METHODS: Twelve patients underwent SBRT at 30-40 Gy. Registration between planning CT and SPECT/CT images was performed, and DFH parameters were calculated as follows: Fx=(sum of the counts within the liver volume receiving a dose of more than x Gy/sum of the counts within the whole liver volume) ×100. The discrepancy between Fx and Vx (Dx) was also calculated. RESULTS: The number of previous treatments for lesions other than SBRT-treated lesions (≥2 vs. <2) exhibited a significant influence on the absolute values of D10, D15, and D20 (p<0.05). CONCLUSION: Previous treatment significantly influences the parametric discrepancy between DFH and DVH. Copyright
BACKGROUND/AIM: We evaluated the influence of previous treatments on the parametric discrepancies between dose-volume histograms (DVHs) and dose-function histograms (DFHs) generated based on 99mTc-GSA SPECT images of hepatocellular carcinoma (HCC) patients treated with stereotactic body radiation therapy (SBRT). PATIENTS AND METHODS: Twelve patients underwent SBRT at 30-40 Gy. Registration between planning CT and SPECT/CT images was performed, and DFH parameters were calculated as follows: Fx=(sum of the counts within the liver volume receiving a dose of more than x Gy/sum of the counts within the whole liver volume) ×100. The discrepancy between Fx and Vx (Dx) was also calculated. RESULTS: The number of previous treatments for lesions other than SBRT-treated lesions (≥2 vs. <2) exhibited a significant influence on the absolute values of D10, D15, and D20 (p<0.05). CONCLUSION: Previous treatment significantly influences the parametric discrepancy between DFH and DVH. Copyright