Long-term follow-up of hairy cell leukemia patients treated with 2-chlorodeoxyadenosine.
OBJECTIVE
The management of patients with hairy cell leukemia (HCL) has evolved significantly over the past two decades. In fact, both 2'-deoxycoformycin (DCF) and 2-chlorodeoxyadenosine (2-CdA) induce complete response (CR) in the majority of the patients with HCL. However, fewer data exist on the long-term follow-up of patients who have undergone the characteristically brief exposure to 2-CdA therapy. Thus, it is important to evaluate such long-term outcome data in order to increase understanding of the efficacy of this agent in the management of HCL.


METHODS
We reviewed the long-term follow-up data of 23 HCL patients pretreated with a-interferon and then treated with 2-CdA administered as a single continuous IV infusion for 7 days at the dose of 0.1 mg/kg/day in our institute between January 1991 and February 1992.


RESULTS
Of 23 patients, 19 (83%) achieved a CR and 4 (17%) a partial response (PR), with an overall response rate of 100%. After a median follow-up of 102 months (range: 96-108), there have been 9 (39%) relapses. In the PR subset 100% of patients relapsed within the first 45 months of follow-up. In the group of patients who obtained a CR, 26% relapsed; all these relapses occurred between 54 and 86 months. Overall, the median time to relapse was 54 months (range: 16-86). All relapsed patients were re-treated with 2-CdA at the dose of 0.15 mg/kg/day for 5 days in a 2-hour infusion, and 67% and 22% then obtained CR or PR, respectively. The median duration of this second response was 48 months (range: 22-80). All but one of these patients are still maintaining the second response to 2-CdA. The 9-year overall and the relapse-free survivals are 91% and 70%, respectively.


CONCLUSIONS
In HCL patients a single dose of 2-CdA induces a long-term CR with a 9-year survival > 90%. Over 50% of patients appear to be clinically cured by this procedure, but the lack of a long-term plateau in the relapse-free survival curve means caution on this point is still warranted.
Zinzani
P L
PL
Istituto di Ematologia e Oncologia Medica "Seràgnoli", Policlinico S.Orsola, Via Massarenti 9, 40138 Bologna, Italy. plzinzo@med.unibo.it.
Magagnoli
M
M
Bendandi
M
M
Tani
M
M
Stefoni
V
V
Cellini
C
C
Poggi
S
S
Piccioli
M
M
Pileri
S
S
Tura
S
S
D000328:Adult; D000368:Aged; D017338:Cladribine / Q000008:administration & dosage* / Q000009:adverse effects; D018572:Disease-Free Survival; D004341:Drug Evaluation; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007943:Leukemia, Hairy Cell / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D012008:Recurrence; D015996:Survival Rate; D016896:Treatment Outcome
D017338:Cladribine