Successful treatment of hairy cell leukemia with beta-ser interferon

Twelve patients with hairy cell leukemia underwent treatment with beta-ser interferon, a type I interferon with potent antiproliferative activity. Ten of the 12 patients had had prior therapy and the median time from diagnosis to initiation of treatment was 8.5 months (range 1 month to 18 years). Bone marrow involvement ranged from 90-100% hairy cells. Beta-ser interferon was administered as an intravenous injection of 90 million units per dose, three times weekly. Dose reductions were by dose and by frequency in individual patients. Ten of 12 patients (83%) responded, including 7 complete (CR) and 3 partial (PR) responses. The median time to at least PR was 6 months and the median time to CR was 12 months. The median duration of overall response (PR + CR or PR) is 31+ months (range 26(+)-40+ months). Of the 6 patients who underwent dose reductions due to toxicity or poor tolerance, 4 CR patients reverted to PR, and 2 PR patients have increased the number of hairy cells in the marrow, while maintaining normal peripheral blood counts. One each of these has regained CR and PR status after an increase in dose.     

Successful treatment of hairy cell leukemia prolymphocytic variant with 2'-deoxycoformycin

The hairy cell leukemia prolymphocytic variant, a subtype of hairy cell leukemia, is an extremely rare disease, especially in Japan. We report a case in which treatment with 2'-deoxycoformycin (DCF) improved the clinical features of the disease. The patient, a 70-year-old female, was first treated with 2-chlorodeoxyadenosine, but showed only transient improvement in the hematological findings. DCF was then administered every week. Following the start of this treatment, the leukemia cell count rapidly decreased and the platelet count simultaneously increased. This effect of DCF has so far been long term. More clinical studies are needed to confirm the therapeutic value of DCF.     

Successful treatment with cladribine for hypoplastic hairy cell leukemia after long-term neutropenia

A 34-year-old woman was admitted to the hospital because of swelling of her right knee, and the result of the laboratory tests indicated anemia and leukocytopenia. A bone marrow examination showed dissemination of small to medium-sized abnormal lymphocytes with abundant and pale blue cytoplasm and a circumferential "hairy" projection in the hypocellular bone marrow. These cells were positive for tartrate-resistant acid phosphatase (TRAP) and for CD 19, CD 20, CD 25, CD 103 and SmIg kappa. The patient was diagnosed as having hypoplastic hairy cell leukemia and received cladribine (2-CdA) for seven days via continuous intravenous injection. The minimum white blood cell count was 300/microl at seven days after starting the therapy (day 7) and the neutrophil count recovered to more than 1500/microl on day 118. The patient achieved complete remission on day 140 without any episodes of severe infection and has remained in complete remission for more than one year. The treatment of hypocellular HCL with 2-CdA might be useful.     

Long-term follow-up of patients with hairy cell leukaemia after treatment with pentostatin or cladribine

We report the long-term follow-up results on two groups of patients with hairy cell leukaemia (HCL) treated with either pentostatin (deoxycoformycin) or cladribine (2-chlorodeoxyadenosine). 165 HCL patients received treatment with pentostatin (between 1986 and 1994), and 45 were treated with cladribine (between 1992 and 1997). Age and sex characteristics were similar in the two groups. 38 patients in the pentostatin group and 12 in the cladribine group were previously untreated. 22 patients in the cladribine group had received prior treatment with pentostatin; four were resistant, 17 had relapsed following partial (four) or complete (13) responses, and one was not evaluable for response. The response rates were the same in the two groups: 82% complete response (CR), 15% partial response (PR) for pentostatin and 84% CR, 16% PR for cladribine. Relapse rates were 24% for pentostatin and 29% for cladribine after median follow-up of 71 and 45 months respectively. At 45 months, however, the relapse rate for pentostatin was only 9.7%. We found a statistically significant difference in the disease-free interval (DFI) between the two groups suggesting that patients may relapse more quickly after cladribine. The majority of relapsed patients achieved second remissions following further therapy with either pentostatin or cladribine, with no evidence of cross resistance between the two agents. The 5-year survival for all patients was 97% and treatment- related toxicity was low. We conclude that both pentostatin and cladribine induce durable remissions in the majority of HCL patients. Longer follow-up is required to establish whether some patients are cured as there is no plateau in DFI, and which of these two agents may be the treatment of choice.     

Successful treatment of a patient with hairy cell leukemia and pentostatin-induced autoimmune thrombocytopenia with rituximab

The treatment of choice for hairy cell leukemia (HCL) are the purine analogs pentostatin and cladribine. They induced complete remissions in up to 85% of patients. Purine analogs are known to induce autoimmune phenomena, but there are no reports of autoimmune thrombocytopenia after treatment with pentostatin. This case report describes the very rare association of pentostatin-treated hairy cell leukemia and autoimmune thrombocytopenia. Encouraged by first reports of promising activity of the anti-CD20 monoclonal antibody rituximab in patients with autoimmune disorders, we decided to treat our patient with rituximab in the conventional dose of 375 mg/m(2) i.v. weekly for 4 cycles. One week after the first administration, the peripheral blood count has recovered with a normal platelet count. 22 weeks after completion of therapy, the patient is still in complete hematologic remission without further medication. In conclusion, rituximab seems to be a new, promising drug in the treatment of refractory autoimmune thrombocytopenia even in patients with underlying lymphoproliferative disorders.     

Long-term follow-up of remission duration, mortality, and second malignancies in hairy cell leukemia patients treated with pentostatin

The nucleoside analogue, pentostatin, has demonstrated high complete response rates and long relapse-free survival times in patients with hairy cell leukemia, a disease that historically had been unresponsive to treatment. Long-term data on duration of overall survival and relapse-free survival and incidence of subsequent malignancies with this agent are lacking. Patients completing the treatment phase of a randomized, intergroup study who received pentostatin as an initial treatment or who crossed over after failure of interferon alpha were followed for survival, relapse, and diagnosis of subsequent malignancies. Two hundred forty-one patients treated with pentostatin as initial therapy (n = 154) or who crossed over after failure of interferon alpha (n = 87) were followed for a median duration of 9.3 years. Estimated 5- and 10-year survival rates (95% confidence interval) for all patients combined were 90% (87%-94%) and 81% (75%-86%), respectively. In the 173 patients with a confirmed complete response to pentostatin treatment, 5- and 10-year relapse-free survival rates were 85% (80%-91%) and 67% (58%-76%), respectively. Survival curves for patients initially treated with pentostatin and those crossed over were similar. Only 2 of 40 deaths were attributed to hairy cell leukemia. The mortality rate and incidence of subsequent malignancies were not higher than expected in the general population. Pentostatin is a highly effective regimen for hairy cell leukemia that produces durable complete responses. Subsequent malignancies do not appear to be increased with pentostatin treatment.     

Persistent bone marrow failure with dysplastic features following pentostatin therapy for hairy cell leukaemia

Myelodysplastic syndromes (MDS) have rarely been reported after treatment with nucleoside analogues, and mainly in patients who have also received alkylating agents. We report a patient who developed MDS (refractory anaemia with ring sideroblasts) after treatment with pentostatin (deoxycoformycin) alone.     

Low-dose deoxycoformycin in the treatment of hairy cell leukemia

Ten patients with progressive hairy cell leukemia were treated with 2'deoxycoformycin (dCF) by intravenous bolus (4 mg/m2) given every other week. All ten patients are evaluable for response and nine of the ten patients have achieved a complete remission. In addition to clearing of hairy cells from the bone marrow, eight patients had resolution of their monocytopenia. Seven of the nine patients remain in unmaintained remission with a median duration of 6.2 months. Two patients have had relapse in the bone marrow alone and continue to have normal peripheral blood counts. They are being followed without treatment. Toxicity was minimal at this low dose with one patient having a mild reversible reduction in creatinine clearance. Four other patients had reversible neutropenia. There were no significant infections associated with treatment. Low-dose deoxycoformycin administered intravenously every other week represents an extremely effective treatment for hairy cell leukemia.     

Tumorous manifestation of hairy cell leukemia after long-term treatment with interferon alpha

Tumorous-manifestation of hairy cell leukemia in a patient treated with IFN for 7 years is described. After this time, while the patient still was in hematological remission, a tumorous involvement of the lung by hairy cells developed and was successfully treated by surgery. No differences in the phenotype of hairy cells in the lung tumor, in the bone marrow, or in the blood could be detected.     

Long-term follow-up of patients with hairy cell leukemia after treatment with 2'-deoxycoformycin

Twenty-four patients with advanced hairy cell leukemia treated with 2'- deoxycoformycin (dCF) were studied after achieving complete remission to determine the impact of treatment on survival, disease-free survival, long-term complications of treatment, and response to retreatment. At a median follow-up time of 82 months (range, 54 to 104 months), 23 of 24 patients remain alive. One patient has died of recurrent disease refractory to treatment. Of the remaining 23 patients, 11 have relapsed at a median time of 30 months (range, 7 to 80 months) after treatment completion. Of these 11 patients, 7 have been retreated with dCF or 2'-chlorodeoxyadenosine (2-CdA), including one patient that was retreated twice. All seven patients have responded, with five patients achieving second complete remission. Two patients have had normalization of blood cell counts, but repeat bone marrows have not been performed. No serious infections have been seen in dCF-treated patients during follow-up. One case of Hodgkin's disease and three cases of skin malignancies have developed in these 24 patients. From initiation of treatment, survival is 93 months (range, 63 to 116 months). We concluded that dCF significantly prolongs the survival of patients with advanced hairy cell leukemia without resultant long-term complications. It is too early to predict if this therapy will be curative for the patients still in remission.     

A hairy B cell lymphoproliferative disorder resembling hairy cell leukemia

This case report describes a hairy B cell lymphoproliferative disorder (HBLD) with clinical and hematological features resembling hairy cell leukemia. The patient was a 29-year-old female who demonstrated atypical lymphocytes in her peripheral blood. Physical examination demonstrated splenomegaly, but there were no palpable superficial lymph nodes. Hematological examination showed a leukocyte count of 10.6 x 10(3)/mm3 with 41% atypical lymphocytes. Bone marrow examination showed a normal cellular and an atypical lymphocyte count of 42%. The atypical lymphocytes had microvilli and prominent membranous ruffles on their surfaces. Atypical lymphocytes expressed CD5- CD10- CD11c+ CD19+ CD20+ CD23- CD25- on the surface of the cells on examination by with a fluorescence activated cell sorter. Although these findings were similar to hairy cell leukemia, Japanese variant, the surface marker of the kappa chain and lambda chain was unbiased and studies of immunoglobulin gene rearrangements and expression showed polyclonal proliferation of B cells. Therefore, we diagnosed this patient as having HBLD. Because she did not demonstrate anemia or thrombocytopenia, she is not currently receiving medication. To date, the atypical lymphocyte count has not changed.     

Treatment of hairy cell leukemia with recombinant alpha-interferon

Thirty patients with hairy cell leukemia were treated with recombinant interferon alpha-A (rIFN alpha A; Roferon-A); seven were previously untreated. Nine complete and 17 partial remissions were documented by bone marrow core biopsies. All patients' peripheral blood hematologic indexes either improved or normalized. Twelve of 13 patients with retroperitoneal or mediastinal adenopathy obtained remissions of tumor masses. All seven patients with splenomegaly showed prompt reduction in the size of the spleen to normal size. The incidence of complete remissions was significantly higher (P = .02) in previously untreated patients (5 of 7) than in those in whom splenectomy had been performed (4 of 23), a result presumed to be related to the pretreatment tumor burden. rIFN alpha A was well tolerated; mild fatigue was the most frequent complaint. In most patients, tumor remissions resulted in an improved quality of life: they eliminated the need for transfusing blood products and reduced the incidence of infections, and immune deficits were apparently restored in some of the patients. We conclude that rIFN alpha A is an effective therapy for all stages of hairy cell leukemia including previously untreated or newly diagnosed patients.     

Surface immunoglobulins on hairy cells of 55 patients with hairy cell leukemia

Surface immunoglobulins (SIg) were determined on peripheral blood samples from 55 patients with hairy cell leukemia (HCL) and on hairy cells from spleen preparations of 14 of these 55 patients. The patterns of SIg for HCL was compared to the patterns on peripheral blood leukemic cells from 39 patients with chronic lymphocytic leukemia (CLL) and 15 patients with poorly differentiated lymphocytic (PDL) lymphoma. Of the 55 HCL patients, 42 could be scored for individual heavy and light chains; 16 had only IgG, 14 had two or three heavy chains, 7 had only IgD, and 5 cases had no SIg and were E-rosette negative. This pattern was different from the B-cell pattern in CLL and PDL where there were few cases of IgG alone (5%) and many cases of IgM alone (50%). Surface marker profile did not correlate with survival in any of the sub-groups tested. HCL appears to be a B-cell lymphoproliferative disease in greater than 90% of cases; many combinations of heavy chains with only a single light chain can be demonstrated.     

Bone lesions in hairy cell leukemia: Diagnosis and treatment

Skeletal involvement is a rare complication of hairy cell leukemia (HCL) with an incidence of approximately 3%. Bone lesions are commonly lytic, and the most common sites of involvement are the femoral head and neck. Skeletal involvement is typically associated with high tumor burden and bone marrow infiltration. However, isolated cases of skeletal disease without splenomegaly or bone marrow involvement are occasionally reported. This review focuses on skeletal lesions in HCL, particularly the pathogenesis, clinical symptoms, diagnostic methods, and treatment approach. A literature review of the MEDLINE database for articles in English concerning hairy cell leukemia, skeletal symptoms, bone involvement was conducted via PubMed. Publications from January 1970 to May 2020 were scrutinized. Additional relevant publications were obtained by reviewing the references from the chosen articles.