Zhu J et al. – Adding bevacizumab to carboplatin and paclitaxel chemotherapy was not associated with better survival among Medicare patients with advanced NSCLC.Methods
- Retrospective cohort study of 4168 Medicare beneficiaries aged 65 years or older with stage IIIB or stage IV non?squamous cell NSCLC diagnosed in 2002-2007 in a Surveillance, Epidemiology, and End Results (SEER) region.
- Patients were categorized into 3 cohorts based on diagnosis year and type of initial chemotherapy administered within 4 months of diagnosis: (1) diagnosis in 2006-2007 and bevacizumab-carboplatin-paclitaxel therapy; (2) diagnosis in 2006-2007 and carboplatin-paclitaxel therapy; or (3) diagnosis in 2002-2005 and carboplatin-paclitaxel therapy.
- The associations between carboplatin-paclitaxel with vs without bevacizumab and overall survival were compared using Cox proportional hazards models and propensity score analyses including information about patient characteristics recorded in SEER-Medicare.
- The median survival estimates were 9.7 (interquartile range [IQR], 4.4-18.6) months for bevacizumab-carboplatin-paclitaxel, 8.9 (IQR, 3.5-19.3) months for carboplatin-paclitaxel in 2006-2007, and 8.0 (IQR, 3.7-17.2) months for carboplatin-paclitaxel in 2002-2005.
- One-year survival probabilities were 39.6% (95% CI, 34.6%-45.4%) for bevacizumab-carboplatin-paclitaxel vs 40.1% (95% CI, 37.4%-43.0%) for carboplatin-paclitaxel in 2006-2007 and 35.6% (95% CI, 33.8%-37.5%) for carboplatin-paclitaxel in 2002-2005.
- Neither multivariable nor propensity score–adjusted Cox models demonstrated a survival advantage for bevacizumab-carboplatin-paclitaxel compared with carboplatin-paclitaxel cohorts. In propensity score–stratified models, the hazard ratio for overall survival for bevacizumab-carboplatin-paclitaxel compared with carboplatin-paclitaxel in 2006-2007 was 1.01 (95% CI, 0.89-1.16; P = .85) and compared with carboplatin-paclitaxel in 2002-2005 was 0.93 (95% CI, 0.83-1.06; P = .28).
- The propensity score–weighted model and propensity score–matching model similarly failed to demonstrate a statistically significant superiority for bevacizumab-carboplatin-paclitaxel.