9/11 and Cancer: Behind the Headlines

As we seem to learn every month or so, reporting on statistics is tricky business (When Skyrocketing Isn’t July 19, 2016). The latest example concerns health risks associated with exposure to the terror attack on the World Trade Center (WTC) on 9/11.

The headlines could easily be interpreted as saying that the cancer risk among people exposed to the WTC disaster has tripled in the past few years, or even that those exposed to the disaster have three times the risk of developing cancer.

It doesn’t say either of those. What is does say is important, and could be easily lost in the coverage.

Cancer was first designated as a WTC-related condition in October of 2012. Coverage of cancer by the WTC health program is based on the presence of probable and known carcinogens in the dust and fumes resulting from the building collapse.

The new reported number (5,441) represents the number of cancers certified for coverage (the number may reflect more than one cancer in a given individual).

The fact is, we really don’t know what number of cancers would be expected in WTC-exposed populations. So far, epidemiological studies of populations who had WTC-exposure generally find modest increases in overall cancer risk, on the order 10 to 30 percent higher than average.

It is important to recognize that it often takes 20 or more years after an exposure for cancers to occur. Only then will we know the real risk. Until then, health officials continue to monitor those exposed to potential carcinogens to identify potential emerging cancer risks.

If you want to learn more about this issue, the American Cancer Society’s Elizabeth M. Ward, PhD, senior vice president of intramural research, recently hosted a roundtable discussion on “Cancer and the World Trade Center Health Program.” Dr. Ward  serves as chair of the World Trade Center Health Program (WTCHP) Scientific and Technical Advisory Committee (STAC).