@article {WATANABE2701, author = {SHOU WATANABE and HIDEYA YAMAZAKI and TAKYUA KIMOTO and GEN SUZUKI and KEI YAMADA}, title = {Repeated Stereotactic Body Radiotherapy for Lung Malignancies: Toxicity Can Be Reduced by Sparing Lung Irradiation}, volume = {42}, number = {5}, pages = {2701--2709}, year = {2022}, doi = {10.21873/anticanres.15748}, publisher = {International Institute of Anticancer Research}, abstract = {Background/Aim: Evidence on the use of repeated stereotactic body radiotherapy (SBRT) is limited. We investigated the efficacy of repeated SBRT and predictors of lung toxicity. Patients and Methods: We reviewed 20 patients (27 lesions) with primary or metastatic lung cancer who underwent repeated SBRT with CyberKnife{\textregistered}. We generated a composite plan for dosimetric analysis based on equivalent doses in 2.0-Gy fractions (α/β=3). Predictors of Grade 2+ radiation pneumonitis (RP) were examined. Results: The median follow-up duration was 18.0 months. The 1-year and 2-year local control were both 95.2\%. Five patients (25\%) developed Grade 2+ RP, including a Grade 5 RP. The Grade 2+ RP group showed higher composite mean lung dose (MLD) and lower lung volumes spared from 5-20 Gy (VS5-VS20). Conclusion: Repeated SBRT with CyberKnife{\textregistered} showed favorable local control, but a high rate of Grade 2+ RP. Accumulated MLD and VS5-VS20 may predict RP.}, issn = {0250-7005}, URL = {https://ar.iiarjournals.org/content/42/5/2701}, eprint = {https://ar.iiarjournals.org/content/42/5/2701.full.pdf}, journal = {Anticancer Research} }