Jerome Groopman in The New Yorker:
For almost thirty years, William Kuhens worked on Staten Island as a basketball referee for the Catholic Youth Organization and other amateur leagues. At seventy, he was physically fit, taking part in twenty games a month. But in July of 2013 he began to lose weight and feel exhausted; his wife told him he looked pale. He saw his doctor, and tests revealed that his blood contained below-normal numbers of platelets and red and white blood cells; these are critical for, respectively, preventing bleeding, supplying oxygen, and combatting infection. Kuhens was sent to the Memorial Sloan Kettering Cancer Center, in Manhattan, to meet with Eytan Stein, an expert in blood disorders. Stein found that as much as fifteen per cent of Kuhens’s bone marrow was made up of primitive, cancerous blood cells. “Mr. Kuhens was on the cusp of leukemia,” Stein told me recently. “It seemed that his disease was rapidly advancing.”
…Stein treated him with four courses of chemotherapy, to no significant effect. The only options were experimental. Stein had sent a sample of Kuhens’s bone marrow to be analyzed for the presence of thirty or so gene mutations that are known to be associated with blood cancers. The tests revealed one notable mutation, in a gene that produces an enzyme called IDH-2.
…This past spring, Kuhens entered the drug trial and received his first dose. Within weeks, the leukemic-cell count in his bone marrow had fallen from fifteen per cent to four per cent, and his counts of healthy blood cells improved markedly; he has been in complete remission for four months.
More here.