The retrospective cohort study, published online last week in the journal Spine, used data from the Washington State Comprehensive Hospital Abstract Reporting System, the Washington State Cancer Registry and death certificates from the Evergreen State. The 16,914 patients had spinal fusions between 2002 and 2010 and were matched according to age, sex and year of treatment; subjects with existing cancer diagnoses were excluded. The endpoint was the 1st cancer diagnosis identified in the cancer registry.
Of the 449 patients with a cancer diagnosis, 2.76% (117 of 4,246) were treated with InFuse, compared with 2.62% (332 of 12,668) of patients not treated with the recombinant human bone morphogenetic protein. For every 1,000 person-years, the incidence rate was similar between the groups, at 9.5 for the InFuse group and 9.0 for the non-InFuse cohort. And there were no differences in the rate of cancer between the groups when segmented by site of fusion or surgical method.
“There was no increase in overall cancer incidence among those receiving [recombinant human bone morphogenetic protein],” the study’s authors wrote, cautioning that theirs and other such studies are limited by their short duration.
“The examination of cancer incidence following rhBMP administration must continue beyond just the 1st several years in order to adequately assess the potential of rhBMP to influence the occurrence of 1 or more types of malignancy,” they wrote.