[Results of treatment in patients with hairy cell leukemia with splenectomy, alpha-interferon and deoxycoformycin]

The ability of interferon alpha and purine analogues to induce long-lasting remissions in the majority of patients with hairy cell leukaemia has revolutionized the treatment [16, 17, 24, 25], but also provoked dilemma and different opinions about the initial treatment or first line therapy. Splenotomy, the first standard treatment, increases peripheral blood counts but half of the patients require a later systemic therapy because of progressive cytopenia. On the other hand, it has been shown that splenotomy performed after achieving complete remission with interferon alpha or purine analogues contributed to spleen infiltration with hairy cells [37, 38].

In our study we analysed results of treatment of 44 patients with hairy cell leukaemia who were followed-up for 8 years. Patients were treated with three treatment modalities, mostly successively. Splenotomy++ was performed in 34 patients as a first line therapy (Group I); interferon alpha in 24 patients; in 10 patients as a first line therapy without splenotomy (Group II) and in 14 patients as a second line therapy after splenotomy (Group III). Deoxycoformycin was given to 5 patients as a third line therapy.

Our results showed that 20 patients (59 percent) treated only with splenotomy were in haematological remission (Group I). The analysis of prognostic variables demonstrated that at diagnosis patients from Group I, treated only with splenotomy, had at diagnosis higher levels of haemoglobin and thrombocyte counts and a lesser degree of bone marrow (b.m.) infiltration with hairy cells (HCs) than they were found in the other two groups of patients (median Hb = 11.3 g/dL, Plt = 133 x 10(9)/L, HCs in b.m. = 77%). Group II had median Hb = 8.6 g/dl, Plt = 72 x 10(9)/L, HCs in b.m. = 88%, and Group III had median Hb = 9.2 10(9)/L, Plt = 61 x 10(9)/L and HCs in b.m = 90%. Survival curves (Kaplan-Meier method) and Log Rank Statistics showed a significant difference in survival-time (Figure 4) among patients groups (p = 0.0427). Group I had median survival of 270 months; Group II 80 months; and Group III 140 months. Our results demonstrated that different prognostic risk groups existed among hairy cell leukaemia patients and could be identified on the basis of Hb level, Plt count and percent of infiltration of hairy cells into bone marrow. At diagnosis the low risk group of patients (Table 1) had levels of haemoglobin more than 11.3 g/dL; platelet counts more than 72 x 10(9)/L; percent of bone marrow infiltration with hairy cells less than 70%, and expression of lambda type of light chains on leukaemic cells. This group of patients was treated only with splenotomy without systemic therapy. In high risk group of patients the levels of haemoglobin were lower than 8.6 g/dL; platelet counts lower than 60 x 10(9)/L; percent of bone marrow infiltration with hairy cells more than 90% and expression of kappa type of light chains on leukaemic cells. The survival of this group of patients, in spite of initial treatment with systemic therapy with interferon alpha, was shorter. Results of treatment with interferon alpha (Group II and Group III) have demonstrated that the duration of remission in patients who were initially splenectomized and later treated with interferon alpha, was longer (median 31 months) than in patients who were treated with interferon alpha without splenotomy (median duration of remission = 13 months) (Table 3). Results of treatment with deoxycoformycin (Table 4) showed that 3/5 of patients achieved complete remission and 2/5 patients achieved partial remission. Four patients were initially splenectomised and att five patients were treated with interferon alpha before deoxycoformycin.

On the basis of our results, splenotomy can be recommended as the first-line therapy for low risk patients with hairy cell leukaemia; interferon alpha should be the first-line therapy in high risk patients, and the second-line therapy in l