[Analysis of clinical and laboratory characteristics and survival with hairy cell leukemia]

To explore the clinical and laboratory characteristics and survival of Chinese patients with hairy cell leukemia (HCL).

A total of 30 HCL patients from August 1990 to March 2012 were retrospectively analyzed.

There were 22 cases with classical HCL (HCL-C) and 8 with variant HCL (HCL-V). Splenomegaly was the most common physical finding. Leukocytosis was found in all cases of HCL-V. But pancytopenia only accounted for 36.4% (8/22) in HCL-C. And 3/5 of HCL-V had abnormal chromosome karyotypes. Ribosomal-lamellae complexes (RLC) were found only in about 3/12 of HCL cases. Chemotherapy regimens including purine nucleoside analogues achieved a better complete remission (CR) rate than other regimens (3/4 vs 1/18, P = 0.012) in HCL-C. The median follow-up period was 27 (1 - 142) months. There was no follow-up loss. Eleven cases progressed and 6 died. The median overall survival (OS) was not reached. And the 1, 3, 6-year OS rates were 84%, 78% and 58% respectively. The median progression-free survival (PFS) was (63 ± 24) months and the 1, 2, 5-year PFS rates were 86%, 72% and 44% respectively. The median PFS of HCL-V was significant shorter than HCL-C ((23 ± 3) vs (78 ± 12) months, P = 0.014). In HCL-C group, fever (P = 0.038) and anemia (P = 0.000) at diagnosis were poor prognostic factors. But purine nucleoside analogues made no significant difference in PFS.

Pancytopenia is infrequent in Chinese HCL patients. And classical RLC is rare under electron microscope. Purine nucleoside analogues may achieve a better CR rate, but fail to improve PFS rate. As compared with HCL-C, HCL-V is common with genetic abnormalities and has a worse prognosis with a shorter PFS.