Recurrence Patterns and Second Primary XXXX After Stereotactic Body Radiation Therapy for Early-Stage Non-Small-Cell Lung Cancer: Implications for Surveillance.

@entity1 @entity286 @entity1149 @entity2
BACKGROUND: @entity1 treated with stereotactic body radiation therapy (SBRT) for early-stage @entity1149 ( @entity1149 ) are subject to locoregional and distant recurrence, as well as the formation of second @entity2 (SPLCs). The optimal surveillance regimen for @entity1 treated with SBRT for early-stage @entity1149 remains unclear; we therefore investigated the posttreatment recurrence patterns and development of SPLCs. METHODS: Three hundred sixty-six @entity1 with pathologically proven inoperable early-stage @entity1149 treated with SBRT between 2006 and 2013 were assessed. @entity1 underwent a computed tomographic (CT) scan of the chest every 3 months during years 1 and 2, every 6 months during years 3 and 4, and annually thereafter. Competing risk analysis was used for all time-to-event analyses. RESULTS: With a median follow-up of 23 months, the 2-year cumulative incidence of local, nodal, and distant treatment failures were 12.2%, 16.1%, and 15.5%, respectively. In @entity1 with disease progression after SBRT (n  = 108), 84% (n  = 91) of cases occurred within the first 2 years. Five percent (n  = 19) of @entity1 experienced SPLCs. The median time to development of an SPLC was 16.5 months (range, 6.5-71.1 months), with 33% (n  = 6) of these @entity1 experiencing SPLCs after 2 years. None of the never smokers, but 4% of former @entity286 smokers and 15% of current @entity286 smokers, experienced an SPLC (P  = .005). CONCLUSION: Close monitoring with routine CT scans within the first 2 years after SBRT is effective in detecting early disease progression. In contrast, the risk for the development of an SPLC remains elevated beyond 2 years, particularly in former and current smokers.
