According to a media outlet, Choi Sung Won was diagnosed with acute leukemia in spring 2016 and was fully cured in December of that year, but has recently been hospitalized after a recurrence in four years. The news surfaced when ChoiŌĆÖs fellow actor Joo Min Jin posted on social media to find a matching donor for a transfusion. He wrote, ŌĆ£IŌĆÖm sorry about posting this in the midst of the COVID-19 pandemic. My friend is urgently in need of transfusion.ŌĆØ Many netizens are sharing their prayers for ChoiŌĆÖs recovery. Meanwhile, Choi Sung Won finally saw the light of day when he appeared in the 2015 drama Reply 1988 as HyeriŌĆÖs little brother Sung No Eul. However, he was diagnosed with acute leukemia in 2016 while filming for Mirror of the Witch and had to halt all activities. He was said to have seen complete recovery in December 2016 and resumed his activities in February 2017. Source (1)

   Reply 1988    Actor Choi Sung Woon Hospitalized due to Relapsed Leukemia - 63