Response to intermediate and standard doses of IFN-β in hairy-cell leukaemia

Vol. 14, No. 9, pp. 779-784, 1990. Printed in Great Britain.

0145-2126/90 $3.00 + .00 Pergamon Press plc

Leukemia Research

R E S P O N S E TO I N T E R M E D I A T E A N D S T A N D A R D DOSES OF IFN-fl IN H A I R Y - C E L L L E U K A E M I A A. M. LIBERATI,* M. FIZZOqTI,* F. DI CLEMENTE,* M. SENATORE,* P. BERRUTO,t B. FALINI,* M. F. MARTELLI* and F. GRIGNANI* *Clinica Medica I Perugia University, Italy and tlstituto di Ricerche Biomediche Antoine Marxer, Ivrea, Italy (Received 10 December 1989. Revision accepted 22 March 1990) Abstract--Thirteen hairy-cell leukaemia patients were treated with IFN-fl (6 x 106IU/m 2) for 7 days, alternate weeks, for three cycles. IFN-fl was then continued at the same dose twice a week for 24 weeks. Treatment was discontinued in 2 non-responders and 2 partial responders (1 haem PR, 1 path PR) because of complications unrelated to IFN. The objective response in the nine patients who completed therapy was 66% (1 CR, 3 path PR and 2 haem PR); 2 patients achieved MR. Responses lasted from 5 to 45+ months. Four newly diagnosed patients and 3 in relapse after discontinuation of IFN-fl therapy (6 x 106 IU/m2), were treated with a lower dose of IFN-fl (2 x 106 IU/m2). The objective response to this dose was 57% (3 path PR, 1 haem PR). Another patient obtained MR. No patient has relapsed 6-12 months after therapy discontinuation. IFN-fl was well tolerated, especially at the lower dose and no chronic toxicity was observed. Therefore IFN-fl may be suggested as an alternative treatment for HCL. Key words: Natural IFN, interferon-fl, hairy ceil, intermediate dose, standard dose, phase II study.

INTRODUCTION

mal evolutionary IFN [12], has intrinsic biological properties [13-18] that differ, in part, from those of IFN-tr. Therefore, the therapeutic efficacy of IFN-fl may be similar, or even superior, to that of various types of IFN-oc Since clinical experience with IFN-fl is limited, we assessed: (a) the therapeutic effectiveness of IFN-fl in previously untreated H C L patients and (b) the response to a second treatment in relapsed patients who had previously responded to IFN-fl.

SINCE it was initially reported that human leukocyte IFN (IFN-cr) produces a significant antileukaemic effect in hairy-cell leukaemia (HCL) [1], several studies involving different types of IFN-tr have confirmed these early observations [2-7]. However, a few H C L patients are initially resistant, or later develop resistance, to the antitumour effect of IFN-tr. In some of these patients, as well as in patients with other IFN-a~ sensitive malignancies, resistance seems to be due to specific neutralizing antibodies to the species of recombinant IFN-tr utilized, rather than to an altered cellular response to the type of molecule used [8-10]. In such patients, treatment with other IFN species, especially natural IFN-tx or IFN-fl has therefore been suggested as salvage therapy [10-11]. IFN-fl has a 30-40% aminoacid homology to IFN-tr. In addition, IFN-fl, postulated to be the pri-

PATIENTS AND M E T H O D S Diagnostic and eligibility criteria HCL was diagnosed on the basis of the clinical picture and the presence of morphologically typical hairy cells (HCs) in the peripheral blood, bone-marrow (BM) and/or spleen, which stained positively for tartrate-resistant acid phosphate (TRAP) and displayed the HCL phenotype at alkaline phosphatase anti-alkaline phosphatase (APAPP) immunostaining with a panel of monoclonal antibodies [1922]. Patients had at least one of the following: haemoglobin (Hb) <12g/dl, needed transfusion, platelets (pits) < 1 0 0 × 109/1, granulocytes (grans) <1.5 x 109/1, W B C count >10 x 109/1, as well as normal liver and kidney functions and no active cardiopulmonary disease, or prior or concomitant malignant diseases.

Abbreviations: HCL, hairy-cell leukaemia; HCs, hairy cells; HCI, HC index; % BM, % bone marrow cellularity; CR, complete remission; path/haem-PR, pathological/ haematological partial response; MR, minor response; IFN(s), interferon(s); TRAP, tartrate-resistant acid phosphatase; APAPP, alkaline phosphatase anti-alkaline phosphatase. Correspondence to: A. M. Liberati, Clinica medica I, Policlinico Monteluce, 06100 Perugia, Italy.

Interferon and treatment schedules Human IFN-fl (specific activity >1 x l0 7 IU/mg protein, 779

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A.M. LIBERATIet al.

Istituto Farmacologico Serono and Sclavo) was prepared as previously described [23]. IFN-/3 was given according to two different schedules: (1) 6 x 106IU/m 2 was administered IV over a period of 6 h for 7 days during alternate weeks for a total of 3 cycles (induction therapy), then continued, at the same dose, twice a week for 24 weeks (maintenance therapy); (2) IFN was given at 2 x 106 IU/ m2/day by 4 h IV infusion for 5 days each week for 4 weeks (induction therapy); treatment was then continued, at the same IFN dose and administration modality, 3 times per week for 11 months (maintenance therapy).

treated with 6 or 2 x 106 I U / m 2 of IFN-/3. R e p e a t e d biopsies performed before the start of IFN therapy failed to document BM infiltration in two patients with overt leukaemia (40 x 109/1 W B C ) and splenomegaly (10 cm and 3 cm below the costal margin), who were therefore presumed to be suffering from pure splenic H C L [28, 29]. One of these was treated with 6 x 106 I U / m 2 and the other with 2 x 106 I U / m 2 IFN-/3.

Follow-up Complete and differential blood counts and chemical analyses were performed weekly during induction therapy and at least once monthly thereafter. BM biopsies (2-4 cm long) and peripheral blood cytospins were obtained from 3 months to 2.5 years after beginning therapy. BM cellularity was assessed as the average percentage of BM spaces occupied by haemopoietic cells (% BM). A HC index (HCI), was calculated with the formula: HCI = % BM cellularity × % HC/10,000 [7]. The percentage of HCs present in the BM was evaluated by morphological criteria alone. Mononuclear cells were separated from peripheral blood samples, resuspended at 1 × 106 cells/ml, cytocentrifuged and APAAP immunostained [19].

Response to 6 x 106 I U / m 2 IFN-~J

Response criteria Response was evaluated according to the criteria proposed by Golomb et al. [24] and defined as: (1) CR: reduction to <5% of HCs in the BM core biopsy, resolution of splenomegaly and adenomegaly, normalization of the peripheral blood counts (Hb/> 12 g/dl, pits/> 100 × 109/ 1, grans/> 1.5 × 109/1); (2) pathologic (path) PR: at least a 50% decrease from baseline of HCs in the BM core biopsy, splenomegaly and adenomegaly and normalization of the peripheral blood counts; (3) haematologic (haem) PR: haematological and clinical improvement as in path PR but no change or <50% decrease from baseline in HCs in the BM core biopsy; (4) MR: normalization of any haematological value that was abnormal at entry, or decrease in HCs, if initially leukaemic, to <5% of peripheral WBCs. Toxicity criteria Toxicity was evaluated according to the WHO criteria [25], and when moderate or severe (grade 2 or 3), treatment was discontinued and then, after relief of symptoms, resumed at 75% and 50% of original dose respectively. Statistical methods The Kruskal-Wallis test [26] was adopted for analyzing Hb values and plt, WBC and gran counts documented before and during IFN treatment. When results were significant, individual comparisons were made by applying the non-parametric Mann-Whitney test [26]. The correlations between the parameters studied and time were performed by applying the analysis of variance to the linear regression analysis [27]. RESULTS Patients Table 1 summarizes the characteristics of patients

Two patients died during treatment; one nonresponder of pneumonia, and the other, who had systemic vasculitis prior to starting IFN therapy, developed an acute mechanical obstruction of the small intestine while in haem PR, either due to adhesive bands, a consequence of previous splenectomy, or a mesenteric vascular occlusion or, more probably, a combination of the two. A n o t h e r 2 patients discontinued IFN-fl treatment; one because of no response at week 7 of maintenance therapy, the other, responsive (path PR), due to increased liver enzymes ( W H O , grade 4). Of the 9 patients who completed therapy, 1 failed to improve and 8 responded. One obtained CR, 5 PR (3 path PR, 2 haem PR) and 2 teukaemic patients MR. Hb, plt and gran values of the 6 objective (CR + PR) and 2 minor responders documented before treatment, at the end of each 3-week induction cycle and at the end of week 1, 5, 9, 13, 17, 21 and 24 of maintenance therapy were statistically analyzed. All Hb and pit values observed from week 13 of maintenance therapy and from the end of the induction therapy onwards were significantly higher than baseline values (p < 0.05). In 4 patients, the transfusional requirement (units of packed red blood cells) decreased from the pretherapy requirement of a mean of 1.1 u / p t / w k to 0 during the 3rd cycle of induction therapy onwards. The 6 patients with baseline gran values 1 x 109/1 had significantly higher values (p < 0.05) from week 5 of maintenance therapy onwards. All increases in haematological indices correlated significantly with time expressed as ranks 0-10 for the various study times (Hb, R = 0.41, p < 0.001 ; plts, R = 0.51,p < 0.001; grans, R = 0.47, p < 0.001). The WBCs of patients with initial values >2 × 109/I tended to remain stable or decrease slightly during treatment, whereas those of patients with initial values ~<2 x 109/1 increased. Table 2 reports the times required for all peripheral haematological counts to normalize and spleen size to decrease. Table 3 shows the pathological findings before and at the end of therapy in the 6 objective responders. It is worth noting that the BM continued to improve in 2 patients (PR) after treatment was

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A phase II trial on IFN-fl in hairy-cell leukaemia

TABLE 1. PATIENTCHARACTERISTICSAND IFN-~ DOSE Group A

Group B

Group C

No previous IFNs 6 x 106 I U / m 2

Relapsed IFN-/3 2 × 106 IU/m 2

Newly diagnosed 2 x 106 I U / m 2

4 9 3%74

0 3 62-74

1 3 48-62

Haemoglobin (g/dl) ~10 >10--~12 >12

8 3 2

1 1 1

1 3

Platelets (109/11 ~50 > 50--~ 100 >100

3 8 2

1 2 0

1 2 1

10 2 1

2 1

0 3 1

White blood ceils (109/1) <10 1>10

9 4

3 0

3 1

Spleen (cm below costal margin) ~>7 ~>3-<7 0-<3 =0

4 2 1 2

0 3 0 0

1 2 1 (I

Patient characteristics Female Male Age (range)

Granulocytes (109/1) ~0.5 >0.5-~<1.5 >1.5

Of the 13 group "A" patients, 4 had had a splenectomy and 1 a short course of corticosteroids. In this group the time lapse between diagnosis and therapy initiation was ~<3 months in 6 patients and/>12 months in 7; in patient group "B" it was I>12 months and in patient group "'C" it was ~3 months.

TABLE 2. TIME REQUIRED FOR PERIPHERAL HAEMATOLOGICALCOUNTS TO NORMALIZE AND SPLEEN SIZE TO REDUCE IN RESPONSIVE PATIENTSAFTERIFN-# THERAPY

IFN-# Haematological indexes

IFN-#

6 × l0 6 IU/m 2 total 8 pts

No, weeks mean (range)

2 x 106 I U / m 2 total 5 pts

No. weeks mean (range)

Haemoglobin (g/dl) I>12

6*

12.(I (3-27)

2*

- - (4-39)

Platelets (llJg/1) ~100

7t

6.8 (l-20)

5t

25.7 (3-53)

Granulocytes (l(/~/1) >11.5

75

15.0 (2-271

35

28.0 (22-35)

White blood cells (109/1) <10

2§

- - (2-3)

--

% reduction in spleen size ~ 5 0 % - < 100% =100%

611 3

2.4 (1-3) 11.0 (3-15)

* Anaemic (Hb <12 g/dl) pts. t Thrombocytopaenic (platelets <100 x 109/1) pts. ~: Granulocytopaenic (<1.0 or <1.5 x 109/1) pts. § Leukaemic (WBCs/>10 x 109/11 pts. I[ Reduction/resolution of splenomegaly.

311 1

36.0 (28-25) - - 28

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A. M. LIBERATIet al.

TABLE 3. HISTOLOGICAL FINDINGS IN PATHOLOGICAL AND/OR HAEMATOLOGICAL RESPONDERS

Patient No.

IFN-# dose (IU/m 2)

1 2 3 4

6x 6× 6x 6×

5

6 × 106 6 × 106

6 7 8 9 10

2x 2x 2x 2x

106 106 106 106 10~ 106 106 106

%BM before/end therapy

%HC-BM before/end therapy

HCI before/end therapy

90/90 90/90* 60/70 90/3(/

90/40 90/10" 10/5 90/30

0.81/0.36 0.81/0.09" 0.06/0.03 0.81/0.09

60/30

80/30

0.48/0.09

90/80 40/50 6(I/50 90/75t 90/90

90/70 90/5 90/10 90/30t 90/90

0.81/0.56 0.36/0.025 0.56/0.05 0.81/0.23t 0.81/0.81

End therapy = 7th month for patients l-6. End therapy = 12th month for patients 7-10. * End therapy BM sample was too small (0.5 cm long) for reliable HCI. t BM sample was obtained at 7th month of therapy (patient still on treatment). The %BM, %HC-BM and HCI were 60, 20, 0.12/50, 0, 0.00 at 9 and 23 months in patient 5, and 80.70, 0.56/50, 20, 0.14 at 7 and 12 months in patient 6 after therapy discontinuation; these findings remained stable in 4 and 2 subsequent biopsies.

discontinued, HCs completely disappeared from the bone marrow biopsy core in one (patient 5, Table 3), while the other (patient 6, Table 3) achieved an up to 20% stable decrease in HC infiltration. The before/end %BM, %HC-BM and HCI in 2 additional patients, who discontinued therapy at 1.5 and 4 months, were 60, 80, 0.54/80, 40, 0.32 and 90, 90, 0.81/70, 90, 0.56 (not shown in the table). Response lasted 6 and 18+ months in the 2 MRs, 4, 5, 5.5, 7 and 27+ months in the 5 PRs and 45+ months in the CR patient. Response duration in the path PR patient, who discontinued treatment at week 12 of maintenance therapy due to increased liver enzyme levels, was 11 months. Only one acute episode of bacterial pneumonia was observed during IFN-fi treatment in responsive patients. Two patients had chronic infective complications at the time of starting IFN therapy (one with recurrent urinary infections and anorectal fistula, the other, with Addison's syndrome due to prior and recurring kidney tuberculosis), which were completely cured. Response to 2 x IO n 1U/m 2 1FN-[3

Therapy was discontinued after 8 months in one relapsed patient who failed to response to 2 x 106 IU/m 2 IFN-/3. In the remaining 6 patients, 5 who have completed the treatment and 1 still undergoing therapy, there were 3 path PRs, 1 haem PR, 1 MR and 1 NR. The Hb, plt, gran and WBC values of the 4 objective (PR) and 1 minor responders recorded before, at the end of each 4 week induction cycle and of each month of maintenance therapy were

statistically analyzed. No significant changes were observed between the Hb baseline value and the total Hb levels recorded during treatment. However, the increasing Hb trend was significantly correlated with time (ranks 0-15 corresponded to the study times; r = 0.35, p = 0.005). Only one patient required red blood (15 U) transfusion, until month 8 of therapy. All pit values documented from month 4 of therapy were significantly higher (p < 0.05) than baseline levels and the platelet correlation time (ranks 0-15 corresponded to the study times) was highly significant (r = 0.44, p = 0.0002). WBCs and grans, which initially decreased, began to rise after week 3 of induction therapy. From month 4 of maintenance therapy, gran levels were significantly higher than baseline values (p < 0.05) and the correlation with time expressed as ranks was highly significant (r = 0.69, p < 0.00001). Table 2 gives times for peripheral blood counts to normalize and spleen size to reduce; Table 3 summarizes the pathological findings before, and at the end of therapy. Responses lasted 10+ months in the MR, 6+ months in the haem PR, and 7+ and 12+ months in the 2/3 path PRs who completed therapy. Toxicity

Treatment with IFN-/3 was well tolerated. Fever (~>38°C) was documented in almost all cases during induction therapy and lasted more than 7 days in 9/13 patients on 6 x 106IU/m 2 and 3/7 on 2 z 106 I U / m 2 IFN-#. Premedication with acetaminophen reduced the severity of, or completely prevented, this side effect. Fever was not

A phase II trial on IFN-fl in hairy-cellleukaemia usually associated with myalgia, headache a n d / o r arthralgia. Grade 1 or 2 ( W H O toxicity criteria) liver enzyme increases were recorded in 8/13 patients on 6 x 106 × I U / m 2 and in 3/7 on 2 × 106 I U / m 2 IFNfl. The patient treated with 6 x 106 I U / m 2 IFN-flwho developed grade 4 liver toxicity failed to improve during the 6 months after termination of IFN-fl. On the basis of his multiple blood transfusion history, we concluded that the altered liver function reflected a non-A non-B hepatitis infection rather than IFN toxicity. Isolated episodes of transient somnolence (5/13), fatigue (4/13) dyspnea (1/13) and diarrhoea (3/13) were noted with the intermediate, but not the lower, dose of IFN-fl. DISCUSSION The efficacy of natural and recombinant tr-IFNs in H C L is now well established [1-6, 24]. An emerging drawback to treating IFN-sensitive neoplasias with recombinant a~-IFNs is the development of neutralizing antibodies that limit their clinical usefulness I8-10]. Since recombinant cr-IFNs cross-react with one another, but not with the parental natural product, the latter may prove an effective second-line therapy in patients who become resistant to recombinant tx-IFNs. IFN-fl is antigenically distinct from IFN-o:, and possesses functional activities that, in part, differ from those of IFN-o:. IFN-fl may therefore provide an alternative primary or salvage therapy for patients with H C L and other IFN-sensitive malignancies. In this trial the objective response rate in 9 patients who received 7 months of 6 × 106 I U / m 2 IFN-/3 was 66%. Another 2 patients achieved MR. Moreover 1 path PR and 1 haem PR were seen in 2 patients treated for less than 7 months. There were 2 path PRs, 1 haem PR, and 1 M R in 4 newly-diagnosed patients treated with a dose of 2 × 106 I U / m z. In addition 1 path PR and 1 MR were observed in the 3 relapsing patients treated with the same lower dose. Overall, the results obtained with a dose of 6 x 106 I U / m 2 are comparable to those reported by Golomb [24], but somewhat inferior to those achieved by W o r m a n [2], Damasio [5], and Quesada [301. In our trial, changes in the peripheral blood counts and BM occurred rapidly and the times required for these variations were similar to those reported for o:-IFNs. The pit count normalized first, then Hb reached control values, while grans were the last to return to normal levels. Five out of 9 patients clinically relapsed 5-11 months after terminating 6 × 106 I U / m 2 IFN-fl therapy, suggesting that, as for various other types of IFN-cr, prolonged therapy is

783

needed. The response duration obtained with the lower IFN-fl dose of 2 × 106 I U / m 2 seems to be comparable with that achieved with the higher dose. In fact, no patients have relapsed 6--12 months after discontinuing therapy. Finally, the absence of persistent fatigue, anorexia and weight loss, at both 6 and 2 × 106 I U / m 2 IFN-fl and the complete tolerance of this molecule when used at the lower dose, indicate the need for trials to compare the therapeutic efficacy and tolerance of various types of IFN-fl with those of different cr-IFNs. REFERENCES 1. Quesada J. R., Reuben J., Manning J. T., Hersh E. M. & Gutterman J. U. (1984) Alpha interferon for induction of remission in hairy-cell leukemia. New Engl. J. Med. 310, 15. 2. Worman C. P., Catovsky D., Bevan P. C., Camba L., Joyner M., Green P. J., Williams H. J. H., Bottomley J. M., Gordon-Smith E. C. & Cawley J. C. (1985) Interferon is effective in hairy-cell leukaemia. Br. J. Haemat. 60, 759. 3. Castaigne S., Sigaux F., Cantell K., Falcoff E., Boiron M., Flandrin G. & Degos L. (1986) Interferon alpha in the treatment of hair cell leukemia. Cancer 57, 1681. 4. Quesada J. R., Hersh E. M., Manning J., Reuben J., Keating M., Schnipper E., Itri L. & Gutterman J. U. (1986) Treatment of hairy cell leukemia with recombinant a-interferon. Blood 68, 493. 5. Damasio E. E., Bernasconi C., Castoldi G. L., Chisesi T., Federico M., Lamparelli T., Lauria F., Pagnucco G., Resegoti L. & Rossi E. (1987) Human lymphoblastoid interferon for hairy cell leukemia: results from the Italian Cooperative Group. Leukemia 1,331. 6. Glapsy J. A.. Jacobs A. D. & Golde D. W. (1987) The UCLA experience with type I interferons in hairy cell leukemia. Leukemia 1,323. 7. Golomb H. M. & Vardiman J. W. (1983) Response to splenectomy in 65 patients with hairy cell leukemia: an evaluation of spleen weight and bone marrow involvement. Blood 61,349. 8. Quesada J. R., Rios A., Swanson D., Trown P. & Gutterman J. U. (1985) Antitumor activity of recombinant-derived interferon alpha in metastatic renal cell carcinoma. J. clin. Oncol. 3, 1522. 9. Von Wussow P., Freund M., Block B., Diedrich H., Poliwoda H. & Deicher H. (1987) Clinical significance of anti-IFN-o~antibody titres during interferon therapy. Lancet ii, 635. 10. Steis R. G., Smith II J. W., Urba W. J., Clark J. W., Itri L. M., Evans L. M., Schoenberger C. & Longo D. L. (1988) Resistance to recombinant interferon alfa-2a in hairy-cell leukemia associated with neutralizing antiinterferon antibodies. New Engl. J. Med. 318, 1409. 11. Michalevicz R., Aderka D., Frisch B. & Revel M. (1988) Interferon-beta induced remission in a hairycell leukemia patient resistant to interferon-alpha. Leukemia Res. 12, 845. 12. DeGrado W. F., Wasserman Z. R. & Chowdhry V. (1982) Sequence and structural homologies among type I and type II interferons. Nature 300, 379.

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