Takaya Yamamoto1, Yuzuru Niibe2, Kazunari Yamada3, Masahiko Aoki4, Hiroshi Onishi5, Kuniaki Katsui6, Yasuhiro Dekura7, Atsushi Nishikawa8, Yoshihiko Manabe9, Hideomi Yamashita10, Keiichi Jingu11. 1. Department of Radiation Oncology, Tohoku University Graduate School of Medicine, Sendai, Japan. Electronic address: t.yamamoto@rad.med.tohoku.ac.jp. 2. Department of Radiology, Toho University Omori Medical Center, Tokyo, Japan; Department of Primary Care and Medical Education, Okayama University, Japan. 3. Department of Radiation Oncology, Seirei Mikatahara General Hospital, Hamamatsu, Japan. 4. Department of Radiation Oncology, Hirosaki University, Japan. 5. Department of Radiology, Yamanashi University, Japan. 6. Department of Proton Beam Therapy, Okayama University, Japan. 7. Department of Radiation Oncology, Keiyu-kai Sapporo Hospital, Japan. 8. Department of Radiation Oncology, Shikoku Cancer Center, Ehime, Japan. 9. Department of Radiology, Nagoya City University, Japan. 10. Department of Radiology, University of Tokyo, Japan. 11. Department of Radiation Oncology, Tohoku University Graduate School of Medicine, Sendai, Japan.
Abstract
BACKGROUND AND PURPOSE: The rate of oncologic pulmonary death after stereotactic body radiotherapy for pulmonary oligometastases has never been reported. The purpose of current study was to investigate the rate of freedom from oncologic pulmonary death (FOPD) and to analyze factors affecting for FOPD. MATERIALS AND METHODS: The inclusion criteria for this retrospective study were that SBRT was performed between 2004 and 2015, the number of metastases was 5 or less, the primary lesion and extrathoracic metastases needed to be controlled before SBRT and a biological effective dose (BED10) of 75 Gy or more was needed. The Kaplan-Meier estimator and the log-rank test were used to calculate and compare the stratified rates of FOPD. The Cox proportional hazards model was used for multivariate analyses (MVA). Primary disease death from a non-oncologic pulmonary cause was censored in model 1 and was excluded in model 2. RESULTS: A total of 1172 patients with 1315 tumors were enrolled. During a median follow-up period of 24.5 months, oncologic pulmonary deaths accounted for 101 of 221 primary disease deaths. The 1-year, 3-year and 5-year FOPD rates in model 1 were 98.2%, 89.4% and 84.0%, respectively. MVA for FOPD revealed that local failure of the irradiated tumor, squamous cell carcinoma pathology, and chemotherapy after SBRT had significant relationships with lower FOPD rates in both model 1 and model 2. CONCLUSIONS: Successful local control of pulmonary oligometastases by SBRT contributed to a higher FOPD rate.
BACKGROUND AND PURPOSE: The rate of oncologic pulmonary death after stereotactic body radiotherapy for pulmonary oligometastases has never been reported. The purpose of current study was to investigate the rate of freedom from oncologic pulmonary death (FOPD) and to analyze factors affecting for FOPD. MATERIALS AND METHODS: The inclusion criteria for this retrospective study were that SBRT was performed between 2004 and 2015, the number of metastases was 5 or less, the primary lesion and extrathoracic metastases needed to be controlled before SBRT and a biological effective dose (BED10) of 75 Gy or more was needed. The Kaplan-Meier estimator and the log-rank test were used to calculate and compare the stratified rates of FOPD. The Cox proportional hazards model was used for multivariate analyses (MVA). Primary disease death from a non-oncologic pulmonary cause was censored in model 1 and was excluded in model 2. RESULTS: A total of 1172 patients with 1315 tumors were enrolled. During a median follow-up period of 24.5 months, oncologic pulmonary deaths accounted for 101 of 221 primary disease deaths. The 1-year, 3-year and 5-year FOPD rates in model 1 were 98.2%, 89.4% and 84.0%, respectively. MVA for FOPD revealed that local failure of the irradiated tumor, squamous cell carcinoma pathology, and chemotherapy after SBRT had significant relationships with lower FOPD rates in both model 1 and model 2. CONCLUSIONS: Successful local control of pulmonary oligometastases by SBRT contributed to a higher FOPD rate.