Dr. Sergei Koralov: A Profile in Courage

They call it the most grueling one-day sporting event in the world, and only those who cross the finish line can lay claim to the title “Ironman.” Nobody would have thought Sergei Koralov among the finishers at the 2016 Lake Placid Ironman—especially not those who saw him immobilized by a recurrent cancer. But Koralov has made a life of shattering expectations and beating the odds.


Born in Moscow, Russia, the son of a linguist and a mathematician, Sergei Koralov grew up in a family immersed in academia. Those who know him today, a leading figure in immunology research at NYU Medical Center, just nod and imagine the apple did not fall far from that tree. But it was never self-evident to his teachers that he would end up following the academic route. While his parents published research papers and his brother burned the midnight oil studying, young Sergei spent most of his time outdoors, climbing onto anything that he could grab hold of. “Are you sure that you are related to your brother?” his teachers would ask, rhetorically. Although most schoolwork bored him, he was captivated by one subject—chemistry. He remembers spending hours concocting explosive and colorful mixtures in his backyard in Moscow with his model chemistry kit.

Sergei was thirteen years old when his father, an extraordinary mathematician, earned his green card and the family immigrated to the United States. It was during this time that Sergei began to come into his own as a student. With a bashful smile and shrug, Sergei claims that he was never at the top of his class, but at least he was no longer bearing the brunt of his poor academic performance. Clearly, he was more successful than his diffident shrug implies, since he earned a place at the highly select Duke University. Then his first hurdle appeared. Around the same time that Sergei received his acceptance letter from Duke, he also received a diagnosis of mucoepidermoid carcinoma (MEC). Eighteen-year-old Sergei went into treatment, underwent surgery, and battled. Remarkably, he was cancer free on his first day at Duke. It would be the first of many comebacks for this comeback kid.

While his parents published research papers and his brother burned the midnight oil studying, young Sergei spent most of his time outdoors, climbing onto anything that he could grab hold of

During his time at Duke, Sergei discovered his affinity for research. He abandoned his long-time dream of becoming a doctor and dove enthusiastically into uncharted territory as a student-technician in an immunology lab. “It was mind-blowing,” Sergei explains, “I was witnessing evolution take place on a molecular scale over a matter of days.” Through such formative laboratory experiences and along with the generous help of influential mentors, Sergei completed a PhD in Immunology and then a Post-Doctoral Fellowship at the Immune Disease Institute of Harvard University. In 2010, he began his Assistant Professorship in the Department of Pathology at NYU Medical Center, where he slowly built a productive and reputable laboratory. Then the next obstacle arose. Hurricane Sandy, which hit NYC in 2012, destroyed his mouse lab. Years of work breeding those mice washed away in Sandy’s currents but, once again, Sergei refused to see the tragedy as anything but a setback. He began to regenerate his mice across multiple facilities and, in a bittersweet turn of events, claimed a breakthrough in immune response research.

However, his own immune response, not his mice’s, was about to claim his attention. After being pronounced cancer-free at the age of eighteen, Sergei had put his diagnosis on a dusty shelf in his past and closed the door. Until, almost two decades later, when he felt an eerily familiar sensation in his mouth. After convincing his physician to perform a diagnostic scan, thirty-four-year-old Sergei was told that he had an aggressive recurrence of the same cancer he thought he had beat years ago. The third hurdle. It was this tumor that led Sergei Koralov to Dr. Mark Urken and into the doors of the THANC Foundation.

Exhausted by two surgeries and external beam radiation, Koralov was forced to take extended time off from his research and to rely on the kindness and dedication of fellow researchers, colleagues, and students to maintain the lab that he had worked so hard to build, and build again. From his hospital bed, aching to return to his former life, he would often tease his wife that he would walk across his hospital room one of these days, and then up and down the corridors, until he could walk straight out of the doors of the hospital. One determined city block grew to one determined mile, until Sergei Koralov was pounding up and over mountaintops.

If there is one thing that crossing the finish line at the Lake Placid Ironman Triathlon means, it’s that nothing—no doubting teacher, no natural disaster and no formidable diagnosis—can quash the courage and persistence of Sergei “Ironman” Koralov.