Radiation oncology (London, England) 2015-02-18
Outcomes of stereotactic body radiotherapy (SBRT) treatment of multiple synchronous and recurrent lung nodules.
Abstract
Background
Stereotactic body radiotherapy (SBRT) is evolving into a standard of care for unresectable lung nodules. Local control has been shown to be in excess of 90% at 3 years. However, some patients present with synchronous lung nodules in the ipsilateral or contralateral lobe or metasynchronous disease. In these cases, patients may receive multiple courses of lung SBRT or a single course for synchronous nodules. The toxicity of such treatment is currently unknown.
Methods
Between 2006 and 2012, 63 subjects with 128 metasynchronous and synchronous lung nodules were treated at the Mayo Clinic with SBRT. Demographic patient data and dosimetric data regarding SBRT treatments were collected. Acute toxicity (defined as toxicity < 90 days) and late toxicity (defined as toxicity > = 90 days) were reported and graded as per standardized CTCAE 4.0 criteria. Local control, progression free survival and overall survival were also described.
Results
The median age of patients treated was 73 years. Sixty five percent were primary or recurrent lung cancers with the remainder metastatic lung nodules of varying histologies. Of 63 patients, 18 had prior high dose external beam radiation to the mediastinum or chest. Dose and fractionation varied but the most common prescriptions were 48 Gy/4 fractions, 54 Gy/3 fractions, and 50 Gy/5 fractions. Only 6 patients demonstrated local recurrence. With a median follow up of 12.6 months, median SBRT specific overall survival and progression free survival were 35.7 months and 10.7 months respectively. Fifty one percent (32/63 patients) experienced acute toxicity, predominantly grade 1 and 2 fatigue. One patient developed acute grade 3 radiation pneumonitis at 75 days. Forty six percent (29/63 patients) developed late effects. Most were grade 1 dyspnea. There was one patient with grade 5 pneumonitis.
Conclusion
Multiple courses of SBRT and SBRT delivery after external beam radiotherapy appear to be feasible and safe. Most toxicity was grade 1 and 2 but the risk was approximately 50% for both acute and late effects.
Related Questions
How do you modify your dose constraints when giving lung SBRT to a new lesion in a patient previously treated with lung SBRT?
Hi @Dr. First Last. I don’t usually change it for lung constraints with a few caveats. Here’s the way I think about it, more or less…First of course, is the patient. How’s their lung function? Are they on O2 or limited in their ADLs? That raises the bar for treatment and constraints. Could they tole...
Would you consider SBRT for multiple bilateral lung primaries and/or a lung primary with metastases to multiple lobes?
This is a difficult situation. There is not a ton of information on SBRT for synchronous lung nodules. Ironically I'm on one of the articles (Owen et al. Radiation Oncology, 2015). We treated 60+ patients with multiple nodules but many of them were metachronus, which is a bit different situation. Si...