Audiences are Aglow With Interest in
Radiation Casualities

By Peter Emanuel, M.D.

Terrorism and Radiation – Are We Ready? That was the headline in Issue 1 of ASH News Daily preceding the Educational Session entitled The Hematologist and Radiation Casualties. After attending this session on Sunday morning all I can say is, WE BETTER BE READY.

Dr. Jamie Waselenko of Walter Reed Army Medical Center provided some gloomy predictions of the outcome of a one kiloton explosion. For reference, the bomb dropped on Hiroshima was on the order of about 15 kilotons. A simple, small one kiloton bomb would result in more than 7,000 near instantaneous deaths but also would result in an estimated 300,000 patients flooding the healthcare system for real or perceived ailments.

Dr. Jim Armitage from the University of Nebraska led off this session with the stark statement that, following the 9/11 incident, a committee was convened, and it was quickly realized that not only was there no existing implementation plan in the event of a radiation attack, there was an obvious lack of education regarding radiation exposure topics across broad groups of audiences.

Dr. Nick Dainiak and Dr. Waselenko delivered quick but lucid primers for the audience to begin the education process. Dr. Dainiak discussed the two forms of ionizing radiation: electromagnetic, which includes x-rays and gamma rays; and particulate, which includes neutrons, protons, and electrons. An incredible estimate is that each day the cells of our body are hit by 1012 collisions with ionizing particles and rays. Dr. Dainiak covered symptoms and signs of the acute radiation syndrome, which occurs at 1 Gy or higher of exposure. He also covered the hematopoietic syndrome (occurring at 2-3 Gy or higher), the gastrointestinal syndrome (occurring at 5-12 Gy), the cutaneous syndrome (occurring at 3-4 Gy or higher), and the neurovascular syndrome (occurring at 15-30 Gy).

We really do need to know about all of this and be ready because there already exists good evidence in the literature that appropriate and timely delivery of supportive care can make a significant difference in patient outcomes. The LD50 for acute radiation exposure, which occurs at 60 days after exposure, is 3.5-4 Gy for unsupported patients vs. 6-7 Gy for patients receiving appropriate supportive care. And much of that care is supposed to be delivered by hematologists. Don’t believe it? Go to the government’s Radiation Emergency Assistance Center (REACT) website where it specifically tells radiation accident victims to “consult with a hematologist.”

Dr. MacVittie finished up this exciting session with a discussion of agents to treat hematopoietic radiation toxicity, including currently approved cytokines, up-and-coming cytokines such as IL-7 and keratinocyte growth factor (KGF), or the potential of cytokine cocktails. There are also emerging novel therapeutics, such as Hollis-Eden Pharmaceutical’s HE2100 compound, highlighted in the presentation of abstract #20.