Kenji Uemoto1,2, Hiroshi Doi3,4, Hiroya Shiomi3, Koichi Yamada3, Daisaku Tatsumi3, Taku Yasumoto3, Masaaki Takashina5, Masahiko Koizumi2, Ryoong-Jin Oh3. 1. Miyakojima IGRT Clinic, Osaka, Japan uemoto@osaka-igrt.or.jp. 2. Division of Health Sciences, Osaka University Graduate School of Medicine and Health Science, Suita, Japan. 3. Miyakojima IGRT Clinic, Osaka, Japan. 4. Department of Radiation Oncology, Kindai University of Medicine, Osaka, Japan. 5. Osaka Heavy Ion Therapy Center, Osaka, Japan.
Abstract
BACKGROUND: This study aimed to assess the need to consider microscopic invasion in terms of treatment planning in stereotactic body radiation therapy (SBRT) for hepatocellular carcinoma and elucidate the appropriate clinical target volume (CTV) margin. PATIENTS AND METHODS: A total of 121 patients (with 146 liver tumors) who underwent SBRT between July 2007 and August 2016 were analyzed, regarding overall survival and local control (LC). RESULTS: The 2- and 5-year LC rates were 91.5% and 89.8%, respectively. Planning target volume (PTV) margin <8 mm was associated with poor LC. Of the 77 patients with PTV margin of <8 mm, age <75 years was associated with poor LC, while alpha-fetoprotein (AFP) ≤20 ng/ml was associated with good LC. CONCLUSION: In patients with high AFP levels, there is a possibility of microscopic invasion around the tumor, suggesting that LC may be improved by adding an additional clinical target volume margin to the gross tumor volume. Copyright
BACKGROUND: This study aimed to assess the need to consider microscopic invasion in terms of treatment planning in stereotactic body radiation therapy (SBRT) for hepatocellular carcinoma and elucidate the appropriate clinical target volume (CTV) margin. PATIENTS AND METHODS: A total of 121 patients (with 146 liver tumors) who underwent SBRT between July 2007 and August 2016 were analyzed, regarding overall survival and local control (LC). RESULTS: The 2- and 5-year LC rates were 91.5% and 89.8%, respectively. Planning target volume (PTV) margin <8 mm was associated with poor LC. Of the 77 patients with PTV margin of <8 mm, age <75 years was associated with poor LC, while alpha-fetoprotein (AFP) ≤20 ng/ml was associated with good LC. CONCLUSION: In patients with high AFP levels, there is a possibility of microscopic invasion around the tumor, suggesting that LC may be improved by adding an additional clinical target volume margin to the gross tumor volume. Copyright