Shohei Komatsu1, Yusuke Demizu2, Nor Shazrina Sulaiman3, Kazuki Terashima3, Masaki Suga4, Masahiro Kido5, Hirochika Toyama5, Sunao Tokumaru3, Tomoaki Okimoto3, Ryohei Sasaki6, Takumi Fukumoto5. 1. Department of Surgery, Division of Hepato-Biliary-Pancreatic Surgery, Kobe University Graduate School of Medicine, Japan. Electronic address: komasho8@med.kobe-u.ac.jp. 2. Department of Radiology, Hyogo Ion Beam Medical Center, Tatsuno, Japan; Department of Radiation Oncology, Hyogo Ion Beam Medical Center Kobe Proton Center, Japan. 3. Department of Radiology, Hyogo Ion Beam Medical Center, Tatsuno, Japan. 4. Department of Radiation Physics, Hyogo Ion Beam Medical Center, Tatsuno, Japan. 5. Department of Surgery, Division of Hepato-Biliary-Pancreatic Surgery, Kobe University Graduate School of Medicine, Japan. 6. Division of Radiation Oncology, Kobe University Graduate School of Medicine, Japan.
Abstract
BACKGROUND: The primary definitive treatment for abdominopelvic sarcomas (APSs) is resection, although incomplete resection has a negative prognostic impact. Although the effectiveness of particle therapy (PT) as a treatment for APS has already been demonstrated, its application for tumors adjacent to the gastrointestinal tract is frequently restricted, due to extremely low tolerance. Space-making PT, consisting of surgical spacer placement and subsequent PT, has been developed to overcome this limitation. MATERIALS AND METHODS: Between June 2006 and June 2018, a total of 75 patients with 12 types of APS underwent space-making PT. RESULTS: The 3-year local control rate of all patients was 90.3%. Fourteen surgery-related complications were observed in 12 patients (16%), and complications of Grade 3b or higher were observed in 3 patients. Ninety-five PT-related complications were seen in 66 patients (88.0%), and 13 patients (17.3%) had complications of Grade 3 or higher. The median V95% (volume irradiated with 95% of the treatment planning dose) of the gross tumor volume and clinical target volume were 99.9% and 99.5%, respectively. The median D95% (dose intensity covering 95% of the target volume) of the gross tumor volume/planned dose and clinical target volume/planned dose were 99.4%, and 99.1%, respectively. CONCLUSION: The feasibility and effectiveness of space-making PT have been demonstrated via dosimetric evaluation, and our results indicate that this new strategy may potentially provide an effective and innovative treatment option for advanced APS.
BACKGROUND: The primary definitive treatment for abdominopelvic sarcomas (APSs) is resection, although incomplete resection has a negative prognostic impact. Although the effectiveness of particle therapy (PT) as a treatment for APS has already been demonstrated, its application for tumors adjacent to the gastrointestinal tract is frequently restricted, due to extremely low tolerance. Space-making PT, consisting of surgical spacer placement and subsequent PT, has been developed to overcome this limitation. MATERIALS AND METHODS: Between June 2006 and June 2018, a total of 75 patients with 12 types of APS underwent space-making PT. RESULTS: The 3-year local control rate of all patients was 90.3%. Fourteen surgery-related complications were observed in 12 patients (16%), and complications of Grade 3b or higher were observed in 3 patients. Ninety-five PT-related complications were seen in 66 patients (88.0%), and 13 patients (17.3%) had complications of Grade 3 or higher. The median V95% (volume irradiated with 95% of the treatment planning dose) of the gross tumor volume and clinical target volume were 99.9% and 99.5%, respectively. The median D95% (dose intensity covering 95% of the target volume) of the gross tumor volume/planned dose and clinical target volume/planned dose were 99.4%, and 99.1%, respectively. CONCLUSION: The feasibility and effectiveness of space-making PT have been demonstrated via dosimetric evaluation, and our results indicate that this new strategy may potentially provide an effective and innovative treatment option for advanced APS.