Firefighters exposed to environmental carcinogens during the World Trade Center (WTC) attacks on September 11, 2001, have a higher prevalence of multiple myeloma (MM) precursor disease and may have a higher chance of developing multiple myeloma, according to a study published in JAMA Oncology.
Although the causes of MM and its precursors, such as monoclonal gammopathy of undetermined significance (MGUS) and light-chain MGUS, are not fully understood, environmental factors such as those released during the WTC attacks and subsequent rescue/recovery efforts may be associated with increased risk.
For this case series, researchers assessed the prevalence of MM among WTC-exposed white firefighters between September 1, 2001, and July 1, 2017, and also evaluated a seroprevalence study of MGUS based on serum samples collected from 781 firefighters between December 2013 and October 2015.
Sixteen firefighters had MM diagnosed at the median age of 57 years; the mean age of myeloma diagnosis in the general population is between 65 and 74 years. Of the 14 patients who had evaluable serum/urine monoclonal protein isotype/free light-chain data, half had light-chain multiple myeloma.
A subgroup analysis of 7 patients showed that 5 (71%) were positive for CD20 expression.
The prevalence rate of MGUS and light-chain MGUS combined once standardized for age was 7.63 per 100, which represents a 1.8-fold higher rate compared with the reference population from Olmsted County, Minnesota (the only available screening study that included both MGUS and light-chain MGUS). The age-standardized rate for light-chain MGUS only was more than 3-fold higher compared with the same reference population.
The authors concluded that “that environmental exposure due to the WTC attacks is associated with myeloma precursor disease (MGUS and light-chain MGUS) and may be a risk factor for the development of multiple myeloma at an earlier age, particularly the light-chain subtype.”
Landgren O, Zeig-Owens R, Giricz O, et al. Multiple myeloma and its precursor disease among firefighters exposed to the World Trade Center Disaster [published online April 26, 2018]. JAMA Oncol. doi: 10.1001/jamaoncol.2018.0509