Does early posttreatment surveillance imaging affect subsequent management following stereotactic body radiation therapy for early-stage XXXX ?

@entity1 @entity5 @entity1149 @entity2 @entity3
PURPOSE: Uncertainty exists regarding the optimal surveillance imaging strategy following stereotactic body radiation therapy (SBRT) for early-stage @entity1149 ( @entity1149 ), particularly with respect to timing. We sought to determine how routine use of early (<6 months) posttreatment imaging affects subsequent management. METHODS AND MATERIALS: The records of all @entity1 treated with SBRT between January 2007 and January 2013 for early-stage @entity1149 were reviewed. Eligible @entity1 underwent >=  1 early (defined as within 6 months following SBRT) surveillance imaging study. Radiographic findings and subsequent diagnostic or therapeutic interventions were identified. Proportions and exact 95% confidence intervals (CI) with early posttreatment surveillance findings and altered treatment were calculated, and cases were examined descriptively. RESULTS: Sixty-two @entity1 with 67 @entity2 underwent 92 early surveillance imaging studies (86 computed tomographic [CT] and 6 positron emission/CT) at a median of 2.1 months (range, 0.1-5.9 months). New lung nodules were identified in 8 @entity1 (13%), leading to a diagnosis of @entity3 treated with systemic therapy in 2 @entity1 and biopsy proven solitary lung recurrence in 2 @entity1 , both treated successfully with local therapy. Tumor growth meeting Response Evaluation Criteria in @entity5 (RECIST) criteria was identified in 1 @entity1 , who was followed with subsequent radiographic regression. In aggregate, the treatment of 4 @entity1 (6.5%, 95% CI 1.7%-15.2%) was altered by early imaging; 2 (3.2%, 95% CI 0.4%-10.8%) with a potentially curative intervention. No predictors for utility of early surveillance were identified. CONCLUSIONS: Imaging within 6 months following SBRT for early-stage @entity1149 resulted in a definitive intervention in approximately 3% of @entity1 . In the era of cost-effective health care, a first scan at 6 months posttreatment may be adequate for most @entity1 . Larger scale prospective studies are needed to address the optimal surveillance regimen following SBRT and to identify @entity1 who may benefit from more aggressive surveillance regimens.
