Risk of cancer following lumbar fusion surgery with recombinant human bone morphogenic protein-2 (rhBMP-2): An analysis using a commercially insured patient population

Abstract

Background: Recombinant human bone morphogenetic protein-2 (rhBMP-2) is frequently used to promote new bone growth after lumbar fusion surgery. However, because BMP receptors are found on cancer cells, there is concern about potential cancer following treatment with rhBMP-2. Data from clinical trials have reported divergent results and have been limited by small sample sizes and relatively short follow-up. We therefore examined the long-term risk of cancer following treatment with rhBMP-2 after lumbar fusion surgery. Methods: Using the MarketScan Commercial Claims and Encounters database, we identified all patients < 65 years without prior cancer who underwent lumbar fusion surgery between October 2003 and December 2009 and were followed at least 3 years after surgery. Development of any Surveillance Epidemiology and End Results malignancy in follow-up was identified through diagnosis and procedure codes. Results: Among 39 448 eligible patients, 2345 (5.9%) received rhBMP at surgery; the median follow-up in this population was 4.87 years. Cancer in follow-up was observed in 49 BMP-treated patients (0.43/100 person years) and 1072 nontreated patients (0.58/100 person years). Use of rhBMP was associated with a cancer risk similar to that of untreated patients in both univariate (hazard ratio, 0.80; 95%, CI 0.54-1.19) and multivariate proportional hazards analyses (hazard ratio, 0.81; 95% CI, 0.54-1.20). Similar findings were observed in a secondary analysis after adjustment for likelihood of rhBMP administration. Conclusions: In this retrospective cohort with at least 3 years of follow-up, administration of rhBMP during lumbar fusion surgery was not associated with an increased risk of subsequent cancer. Level of Evidence: 4 Lumbar Spine.