PURPOSE: Stereotactic body radiotherapy (SBRT) has gained popularity in the treatment of early-stage non-small-cell lung cancer (NSCLC) because of its ability to deliver conformal radiation doses to small targets. However, photon-based SBRT (xSBRT) is associated with significant grade 3+ toxicities. In this study, we compare xSBRT treatment plans with proton-based SBRT (pSBRT) to determine whether dose to normal structures could be reduced if SBRT was delivered with protons. MATERIALS AND METHODS: Eight patients with medically inoperable, peripherally located stage I NSCLC were treated with xSBRT to 48 Gy in 4 12-Gy fractions. These patients were retrospectively re-planned using the same treatment volumes with 3-dimensional conformal double-scatter proton therapy. A Wilcoxon paired test compared dosimetric parameters between the plans for each patient. RESULTS: Compared with xSBRT there was a dosimetric improvement with pSBRT for these volumes: lung V5 (median difference [MD]=10.4%, p=0.01); V10 (MD=6.4%, p=0.01); V20 (MD=2.1%, p=0.01); V40 (MD=1.5%, p=0.05); and mean lung dose (MD=2.17 Gy, p=0.01). There were also benefits (p=<0.05) in D0.1cm3 and D5cm3 with pSBRT to the heart, esophagus, and bronchus. CONCLUSIONS: In a dosimetric comparison between photon and proton-based SBRT, protons resulted in lower doses to critical organs at risk and a smaller volume of non-targeted normal lung exposed to radiation (V5, V10, V20, and V40). The clinical significance and relevance of these dosimetric improvements remain unknown.
PURPOSE: Stereotactic body radiotherapy (SBRT) has gained popularity in the treatment of early-stage non-small-cell lung cancer (NSCLC) because of its ability to deliver conformal radiation doses to small targets. However, photon-based SBRT (xSBRT) is associated with significant grade 3+ toxicities. In this study, we compare xSBRT treatment plans with proton-based SBRT (pSBRT) to determine whether dose to normal structures could be reduced if SBRT was delivered with protons. MATERIALS AND METHODS: Eight patients with medically inoperable, peripherally located stage I NSCLC were treated with xSBRT to 48 Gy in 4 12-Gy fractions. These patients were retrospectively re-planned using the same treatment volumes with 3-dimensional conformal double-scatter proton therapy. A Wilcoxon paired test compared dosimetric parameters between the plans for each patient. RESULTS: Compared with xSBRT there was a dosimetric improvement with pSBRT for these volumes: lung V5 (median difference [MD]=10.4%, p=0.01); V10 (MD=6.4%, p=0.01); V20 (MD=2.1%, p=0.01); V40 (MD=1.5%, p=0.05); and mean lung dose (MD=2.17 Gy, p=0.01). There were also benefits (p=<0.05) in D0.1cm3 and D5cm3 with pSBRT to the heart, esophagus, and bronchus. CONCLUSIONS: In a dosimetric comparison between photon and proton-based SBRT, protons resulted in lower doses to critical organs at risk and a smaller volume of non-targeted normal lung exposed to radiation (V5, V10, V20, and V40). The clinical significance and relevance of these dosimetric improvements remain unknown.
Authors: Arya Amini; Katherine Ciura; James Welsh; Ngoc Nguyen; Matt Palmer; Pamela K Allen; Michael Paolini; Zhongxing Liao; Jaques Bluett; Radhe Mohan; Daniel Gomez; James D Cox; Ritsuko Komaki; Joe Y Chang Journal: Med Dosim Date: 2013 Impact factor: 1.482
Authors: Charles B Simone; David Ly; Tu D Dan; John Ondos; Holly Ning; Arnaud Belard; John O'Connell; Robert W Miller; Nicole L Simone Journal: Radiother Oncol Date: 2011-06-12 Impact factor: 6.280
Authors: Joe Y Chang; Wencheng Zhang; Ritsuko Komaki; Noah C Choi; Shen Chan; Daniel Gomez; Michael O'Reilly; Melenda Jeter; Michael Gillin; Xiaorong Zhu; Xiaodong Zhang; Radhe Mohan; Stephen Swisher; Stephen Hahn; James D Cox Journal: Radiother Oncol Date: 2017-01-28 Impact factor: 6.280
Authors: Tejan P Diwanji; Pranshu Mohindra; Melissa Vyfhuis; James W Snider; Chaitanya Kalavagunta; Sina Mossahebi; Jen Yu; Steven Feigenberg; Shahed N Badiyan Journal: Transl Lung Cancer Res Date: 2017-04