Abstract
Purpose: To minimize toxicity while maintaining tumor coverage with stereotactic body radiation therapy (SBRT) for centrally or superiorly located stage I non-small-cell lung cancer (NSCLC), we investigated passive-scattering proton therapy (PSPT) and intensity-modulated proton therapy (IMPT). Methods and Materials: Fifteen patients with centrally or superiorly located (within 2 cm of critical structures) stage I NSCLC were treated clinically with three-dimensional photon SBRT (50 Gy in 4 fractions). The photon SBRT plan was compared with the PSPT and IMPT plans. The maximum tolerated dose (MTD) was defined as the dose that exceeded the dose - volume constraints in the critical structures. Results: Only 6 photon plans satisfied the >95% planning target volume (PTV) coverage and MTD constraints, compared to 12 PSPT plans (p = 0.009) and 14 IMPT plans (p = 0.001). Compared with the photon SBRT plans, the PSPT and IMPT plans significantly reduced the mean total lung dose from 5.4 Gy to 3.5 Gy (p < 0.001) and 2.8 Gy (p < 0.001) and reduced the total lung volume receiving 5 Gy, 10 Gy, and 20 Gy (p < 0.001). When the PTV was within 2 cm of the critical structures, the PSPT and IMPT plans significantly reduced the mean maximal dose to the aorta, brachial plexus, heart, pulmonary vessels, and spinal cord. Conclusions: For centrally or superiorly located stage I NSCLC, proton therapy, particularly IMPT, delivered ablative doses to the target volume and significantly reduced doses to the surrounding normal tissues compared with photon SBRT.
Original language | English (US) |
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Pages (from-to) | 1015-1022 |
Number of pages | 8 |
Journal | International Journal of Radiation Oncology Biology Physics |
Volume | 80 |
Issue number | 4 |
DOIs | |
State | Published - Jul 15 2011 |
Keywords
- Centrally located lesion
- Non-small-cell lung cancer
- Proton therapy
- Stage I
- Stereotactic body radiation therapy
ASJC Scopus subject areas
- Radiation
- Oncology
- Radiology Nuclear Medicine and imaging
- Cancer Research