TMC PULSE

t m c » p u l s e | s e p t e m b e r 2 0 1 9 4 Remembering Chernobyl Two physicians flew to Moscow in 1986 to treat patients exposed to radiation H BO and Sky Atlantic's recent miniseries, "Chernobyl," drama- tizes the nuclear accident that took place on April 26, 1986 in the former Soviet Union. But the medical after- math of that event was part of a real- life drama for two Texas Medical Center doctors who traveled to Moscow to treat first responders exposed to excessive amounts of radiation at the scene. The disaster occurred after oper- ators disabled the control system on the nuclear reactor as part of a safety test, creating unstable power levels. Combined with a flawed reac- tor design, this caused a massive explosion and fires that pumped at least 5 percent of the radioactive core into the air, according to the World Nuclear Association. Within two weeks of the acci- dent, four doctors from the United States arrived in Moscow, where victims—primarily firefighters who were the first on the scene of the explosion and exposed to high amounts of radiation—were evacu- ated for treatment. Depictions of the victims in the Emmy-nominated five-episode miniseries were extremely realistic, according to Richard E. Champlin, M.D., who was among the doctors who worked with a Russian hospital to perform potentially lifesaving bone marrow transplants. He was a part of the bone marrow trans- plant program at the University of California, Los Angeles at the time. "It was an emergency in which people had received, in many cases, lethal doses of radiation," recalled Champlin, now chair of the department of stem cell transplan- tation and cellular therapy at The University of Texas MD Anderson Cancer Center. "The one treatment B y S h a n l e y P i e r c e that might help them was a bone marrow transplant, since radia- tion is primarily toxic to the bone marrow and suppresses your blood counts where people then die of infections." As a result of the nuclear reactor explosion, 134 people involved with the clean-up were confirmed to have acute radiation syndrome. Within a few weeks, 28 of them died due to radiation. "When people are exposed to high doses of radiation, it can cause fatal bone marrow suppression," Champlin said. "With radiation accidents, if you receive a low dose of radiation, you don't need a transplant, but if you are exposed to a dose that is around 300 to 500 rads of radiation [a rad is a unit of absorbed radiation dose]—that is potentially fatal. You can be saved with a bone marrow transplant. If you get much higher doses of that, it unfortunately destroys other organs of the body and that is what happened to many of the victims in Chernobyl. They died of gastroin- testinal toxicity and radiation." Although the victims did not carry any radiation dosimetry devices to measure the doses of radiation they received, doctors ran biological tests to estimate how much radiation was absorbed. According to Champlin, they received 500 rads of radiation. "For the victims involved, they had terrible injuries. No treatment could have saved most of them," Champlin said. "Bone marrow trans- plantation is of very little benefit in the overall scheme of things in managing patients with radiation injuries. The primary lesson is to prevent this type of accident from happening in the future." One of the other doctors recruited to treat radiation exposure after the Chernobyl disaster was immunologist Yair Reisner, Ph.D., now a professor in the department of stem cell transplantation at MD Anderson. Reisner specialized in bone marrow transplantation from mismatched donors and had devel- oped a procedure to avoid graft versus host disease, a condition in which the donor bone marrow and the recipient's own bone marrow attack each other. Due to the limited resources avail- able in Moscow, Reisner shipped 16 crates of supplies to build his small lab in a Russian hospital. Over the course of two weeks in Moscow, Reisner, Champlin and the other two doctors performed bone marrow transplants on 13 patients. Only two survived. "The bone marrow transplant worked in those two patients and, ultimately, their own bone marrow slowly recovered over time, but the transplant helped them survive the immediate effects of the radiation," Champlin said. "They were very sick and, in many cases, too sick, and received too much radiation to their GI tract for the bone marrow transplant to save them." Champlin brought his insights and experience from treat- ing Chernobyl patients to MD Anderson, where he uses bone marrow transplantation to success- fully treat leukemia, lymphoma and blood cancer. Chernobyl was "an international event with a lot of interest around the world in the outcome of the treatment of the patients," he said. "It was an exciting medical opportu- nity, but, obviously, a tragic event for the victims involved." For Reisner, it was not only a poignant medical and scientific experience, but a human experience, as well. "Being there during the Cold War with the Russians, for me, as a young man, was very special … to be able to talk to them, learn about their lives and so on," Reisner recalled. "It's not less important than the science." The miniseries "Chernobyl" dramatizes the 1986 nuclear accident in the former Soviet Union. Credit: HBO courtesy photo

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