Increase in the use of lung stereotactic body radiotherapy without a preceding biopsy in the United States

Background

Stereotactic body radiotherapy (SBRT) is an efficacious treatment for early stage non-small cell lung cancer (NSCLC). Patients with clinically suspected NSCLC may have medical comorbidities that increase biopsy risks, making them more likely to receive SBRT without biopsy. This study characterizes the pervasiveness of this management approach nationally.

Methods

Patients with stage I NSCLC who received SBRT from 2003 to 2011 were identified within National Cancer Database. Changes in the proportion treated without biopsy were compared by year of diagnosis using binomial logistic regression. Demographics were compared between patients with and without biopsy with Chi-square and t-tests. Multivariate logistic regression was used to determine factors independently associated with SBRT delivery without biopsy.

Results

We identified 6960 patients. Most had biopsy before SBRT (95.5%). Over time the proportion treated without biopsy increased (OR 1.11, p = 0.038). Univariate comparisons demonstrated that older, medically inoperable patients treated at academic centers located in the New England or Pacific regions were less likely to have biopsy before SBRT. Facility type and location (p < 0.001), medical inoperability (p < 0.001), and smaller tumor size (p = 0.013) were associated with odds of SBRT without biopsy in multivariate analyses. A trend toward increased use of SBRT with a biopsy with later year of diagnosis (p = 0.093) was observed in multivariate analysis.

Conclusions

The percentage of patients nationally undergoing SBRT without biopsy has increased over time. The reasons for this trend and ramifications of this approach on cost-effectiveness of care must be studied.