Hairy cell leukemia: a five-year update on seventy-one patients.

An updated analysis was done of 71 patients with hairy cell leukemia originally reported in 1978; 36 patients (51%) had died, 28 (39%) were still alive, and 7 (10%) were lost to follow-up. The median actuarial survival time for the entire group from the onset of symptoms was 70 months. Of the 28 known living patients, 8 had been followed for 12 years or more; the longest survivor has remained alive 289 months after the onset of symptoms. Eleven of the original 71 patients required no therapy; 5 remained alive 5 years or more. Causes of death included progressive disease in 4 patients, infections in 20, hemorrhage in 1, unknown causes in 4, and nonhematologic causes in 7.