Second time’s a charm.
The Study: This is a retrospective look at over 900 patients prospectively registered in an MD Anderson database of definitive SBRT for inoperable early stage lung cancer. The median age was 78, and all patients had initial PET staging. Everyone received 50 Gy in 4 fractions if constraints on central structures were met (79%) and 70 Gy in 10 fractions (14%) or something lower (8%) if not. Plus, some got simultaneous boosts to 60 Gy in 4 or 85 Gy in 10 inside the GTV when possible. Only 92 patients (11%) had an isolated recurrence. Half were in the treatment field at a median of 14 months, and the other half in regional nodes at a median of 9 months. Of these failures, 85% received salvage therapy per an NCCN-esque algorithm outlined in Figure 1, with no salvage treatment-related mortality. Rates of overall survival at 5 years from initial SBRT were the same for those treated with salvage therapy for local recurrence (58%) as for those without recurrence at all (55%). For those treated with salvage therapy for nodal recurrence it was 33%, which is right on par with that of those treated upfront for locally-advanced disease.
Bottom Line: Not many people have local recurrences after SBRT for early stage lung cancer, but there are safe and effective re-treatment algorithms if they do. | Brooks, JAMA 2018