Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology 2014-08
Stereotactic ablative radiotherapy (SABR) using 70 Gy in 10 fractions for non-small cell lung cancer: exploration of clinical indications.
Abstract
Background and purpose
We report our outcomes for patients with NSCLC treated with SABR to 70 Gy in 10 fractions and propose indications for this regimen as well as new dose-volume constraints.
Materials and methods
Volumetric image-guided SABR was used to treat 82 patients with clinical challenging NSCLC, not suitable for 50 Gy in 4 fractions, to a final dose of 70 Gy in 10 fractions. Endpoints included overall survival (OS), toxicity, and disease control.
Results
At a median follow-up time of 21.1 months, 2-year OS and local control rates were 66.9% and 96.2%, respectively. The most common side effects were radiation pneumonitis (14.6% grade 2, 2.4% grade 3), followed by chest wall pain (4.9% grade 2, 1.2% grade 3). Multivariate analysis revealed chest wall V50>60 cm(3) to be associated with chest wall pain. No patient developed brachial plexopathy. One patient with bronchial tree tumor invasion died of hemoptysis.
Conclusions
SABR with 70 Gy in 10 fractions appears to achieve excellent local control and acceptable toxicity for clinically challenging cases with improved tolerance of the chest wall and brachial plexus as compared with 50 Gy in 4 fractions. This regimen may not be suitable in patients with tumor invading critical central structures. More studies are needed to validate our conclusions.
Related Questions
Is there a chest wall constraint you typically use for 60 Gy in 15 fraction NSCLC treatment?
We generally keep chest wall Dmax <110% and keep as much 105% out of the chest wall as possible, with a very low-priority goal of V4000 cGy <30 cc. I am definitely not strict about this in most cases, especially the volumetric goal.
What dose constraints do you use when treating ultra-central lung tumors with a hypofractionated/ultra-hypofractionated approach using 8-10 fractions?
Typically, ultra-central lung tumors mean that they abut/invade critical central structures such as the bronchial tree, tracheal, esophagus, major vessels, etc. For these critical structures, particularly for the esophagus, bronchial tree and tracheal, ablative dose could cause severe chronic toxici...
In patients with oligometastatic disease, would you offer SBRT to a metastatic lymph node abutting the trachea and/or esophagus?
I have treated oligometastatic lymph nodes abutting esophagus and trachea. I do not do this routinely and the risks and benefits need to be weighed in terms of whether the patient is truly oligometastatic and if there are potentially effective systemic options.For these ultracentral locations, I fav...
How do you treat inoperable T1-2N0 apical lung cancers near the brachial plexus but without extension outside the lung?
This is a challenging question, and there are certainly a range of reasonable answers. I would agree with @Dr. First Last that the Forquer/Timmerman paper establishes there is significant risk of plexopathy when exceeding 24-26 Gy in 3 fractions. On the other hand SBRT offers superior local control ...