[Hairy cell leukemia and pregnancy]. / Volosatokletochnyi leikoz i beremennost'.

The paper presents experience in following up and treating hairy cell leukemia (HCL) during pregnancy. The combination of HCL and pregnancy was observed in 5 patients. The patients' median age was 35 years (range, 28-42 years). The diagnosis of HCL was based on a conventional examination protocol: clinical blood analysis with the morphological assessment of lymphocytes, a myelogram and trepanobiopsy, immunophenotypic analysis of lymphocytes or bone marrow (in all the patients), cytochemical determination of tartrate-resistant acid phosphatase in 3 patients, and identification of BRAFV600E mutation in 3 patients. Three pregnant women were treated for HCL in the postpartum period. In one patient with HCL, pregnancy was seen in remission after treatment with cladribine. In one patient with HCL detected at 11 weeks' gestation, interferon-α therapy during the second trimester of pregnancy was performed for increased cytopenia, which was followed by cladribine therapy after delivery. Pregnancy and delivery were uncomplicated in all the patients; 3 patients had vaginal delivery and 2 patients underwent cesarean section. All infants were healthy, with no developmental abnormalities during a follow-up period of 6-140 months (median 30 months). All the patients with HCL are currently in remission: 4 patients in first remission at a follow-up of 10 to 48 months (median 15 months) and one patient in second remission at a follow-up of 88 months. Possible observational tactics is possible when HCL is detected during pregnancy. Treatment of HCL during pregnancy is necessary in cases of deep or progressive cytopenia and/or splenomegaly. The use of interferon-α or splenectomy is preferable.

Update on the biology and treatment options for hairy cell leukemia.

Hairy cell leukemia (HCL) is an uncommon chronic leukemia of mature B cells. Leukemic B cells of HCL exhibit a characteristic morphology and immunophenotype and coexpress multiple clonally related immunoglobulin isotypes. Precise diagnosis and detailed workup is essential, because the clinical profile of HCL can closely mimic that of other chronic B-cell lymphoproliferative disorders that are treated differently. Variants of HCL, such as HCLv and VH4-34 molecular variant, vary in the immunophenotype and specific VH gene usage, and have been more resistant to available treatments. On the contrary, classic HCL is a highly curable disease. Most patients show an excellent long-term response to treatment with single-agent cladribine or pentostatin, with or without the addition of an anti-CD20 monoclonal antibody such as rituximab. However, approximately 30-40 % of patients with HCL relapse after therapy; this can be treated with the same purine analogue that was used for the initial treatment. Advanced molecular techniques have identified distinct molecular aberrations in the Raf/MEK-ERK pathway and BRAF (V600E) mutations that drive the proliferation and survival of HCL B cells. Currently, research in the field of HCL is focused on identifying novel therapeutic targets and potential agents that are safe and can universally cure the disease. Ongoing and planned clinical trials are assessing various treatment strategies, such as the combination of purine analogues and various anti-CD20 monoclonal antibodies, recombinant immunotoxins targeting CD22 (e.g., moxetumomab pasudotox), BRAF inhibitors, such as vemurafenib, and B-cell receptor signaling inhibitors, such as ibrutinib, which is a Bruton's tyrosine kinase inhibitor. This article provides an update of our current understanding of the pathophysiology of HCL and the treatment options available for patients with classic HCL. Discussion of variant forms of HCL is beyond the scope of this manuscript.

Simultaneous presentation of hairy cell leukemia and metastatic signet ring carcinoma of the stomach diagnosed by bone marrow biopsy.

Hairy cell leukemia (HCL) is a rare chronic B-cell disorder with an increased risk of second tumors. The relative risk of second cancers reported in various series of HCL patients ranged from 0.95 to 4.33, but simultaneous presentation of HCL and other epithelial malignancies is very rare. To our knowledge, we present the first case of the coexistence of signet ring carcinoma of the stomach and HCL. We report a case of the simultaneous presentation of HCL and metastasis of the primary signet ring cell carcinoma of the stomach to the bone marrow and skin. A bone marrow biopsy was performed on a patient with pancytopenia. A histologic examination with immunostaining of the bone marrow specimen showed the presence of signet ring carcinoma cells in addition to HCL. As a consequence, our patient underwent further diagnostic procedures including endo-gastro-duodenoscopy with biopsy of gastric tumor mass, which established the diagnosis of gastric signet ring cell carcinoma.

Modern strategies for hairy cell leukemia.

Enormous progress in the treatment of hairy cell leukemia over the last five decades has emerged as a result of organized clinical investigations. Although interferon represented one of the initial major therapeutic advances in the management of this disease in 1984, the subsequent introduction of purine nucleoside analogs (pentostatin and cladribine) changed the natural history of this rare disease by achieving a high rate of complete and durable remissions. The disease-free survival after effective therapy has not reached a plateau, suggesting control but not cure of the disease. Identification of minimal residual disease in patients achieving a complete hematologic remission provides insight into the potential source for predicting eventual relapse. Modern strategies of targeted therapies directed against immunophenotypic markers on the leukemic cells provide hope that improved long-term control of the disease is possible. Combined chemoimmunotherapy may hold the highest promise for disease eradication, but the optimal strategy for using this approach is under active investigation. Despite the perception by hematologists that this disease has already been conquered, there are critically important unanswered questions that remain. Investigation of the bone marrow microenvironment and its impact on minimal residual disease may ultimately prevent relapse. Consideration of the median age of patients at diagnosis combined with a substantial relapse rate mandates continued pursuit of improved therapy. The ultimate goal will be to achieve cure rather than simple control of the disease.

Interferon-alpha is a very effective salvage therapy for patients with hairy cell leukemia relapsing after cladribine: a report of three cases.

Therapy with a purine analogue (cladribine or pentostatin, most often cladribine) has revolutionized the care of patients with hairy cell leukemia, resulting in very long-lasting remissions in the majority of cases. For patients who relapse, re-induction with cladribine again induces durable remissions. For patients with short remission durations, rituximab can be effective, and for a small proportion of patients with more resistant disease, BL22 has been used successfully. I report three cases in which alpha interferon induction and maintenance has produced ongoing remissions in patients with short remission durations after cladribine. One patient had also not responded to rituximab. Alpha interferon may be a very effective treatment option for selected patients with relapsed hairy cell leukemia.

The biology of hairy cell leukemia.

As in all malignancies, the biology of HCL reflects both the behaviour of the malignant cells (hairy cells) themselves and their two-way interaction with the microenvironment. However, the tissue interactions of HCs are particularly striking and involve extensive remodelling of bone marrow, spleen and liver, with relative sparing of lymph nodes. The mechanistic basis of this remodelling is now largely understood and is described herein. Regarding HCs themselves, they are late clonal B cells which have often undergone heavy-chain-isotype class switching and whose VH genes are usually mutated. HCs are highly activated cells in which a number of signalling pathways are constitutively active. This activation determines many of the specific features of HCs, but its cause remains unknown.

Risk factors for severe infection in patients with hairy cell leukemia: a long-term study of 73 patients.

Although the survival of patients with hairy cell leukemia (HCL) has been improved by the therapeutic introduction of interferon alpha and purine analogs, it is still worsened by complications such as severe infections. In this long-term study, we identified factors influencing patient outcomes in 73 patients with HCL. Median age at diagnosis was 53 yr and the gender ratio (M/F) was 2.3. At the time of HCL diagnosis, 60 patients (82%) were symptomatic and 22 of these had an infection. After a median follow-up of 13 yr, eight patients had died of secondary cancer (n = 2), HCL progression (n = 1) and age-related complications (n = 5). The 10-yr overall survival (OS), progression-free survival and relapse rates were 91 +/- 3%, 14 +/- 5% and 87 +/- 5%, respectively. In multivariate analyses, age >53 yr was the only factor adversely influencing OS and secondary cancer incidence, with adjusted hazard ratio (HR) of 9.30 (95%CI, 1.15-76.6; P = 0.037) and 2.80 (95%CI, 1.05-7.71; P = 0.04), respectively. Eleven patients developed severe infections. Absolute lymphocyte count (<1 x 10(9)/L) at diagnosis was the only factor influencing the occurrence of severe infections, with an adjusted HR of 4.01 (P = 0.007). Strikingly, we did not observe any significant correlation between neutrophil or monocyte counts and the incidence of infection. We confirmed long-term survival in HCL but found a high incidence of infection - even late in the course of the disease. The absolute lymphocyte count at diagnosis is a risk factor for the occurrence of severe infections. In addition to careful monitoring of infections, prompt initiation of anti-HCL treatment should be considered in patients with low lymphocyte counts.

Defective interferon-gamma production in patients with hairy cell leukaemia.

BACKGROUND: Patients with hairy cell leukaemia (HCL) have an increased susceptibility to intracellular pathogens, such as mycobacteria and Listeria. Although several abnormalities of T-cell populations have been described in HCL, the effector mechanism responsible for the increased susceptibility to infections is not known. METHODS: Blood was collected from 11 patients with HCL and 22 age- and gender-matched volunteers. Proinflammatory cytokine production by freshly isolated mononuclear cells was stimulated with either lipopolysaccharide or various heat-killed microorganisms. Cytokine concentrations were assessed by specific ELISAs. RESULTS: We demonstrate that mononuclear cells harvested from HCL patients have a specific defect of IFNgamma production when stimulated with a broad panel of bacterial stimuli. In contrast, the production of other proinflammatory cytokines, such as TNF, IL-1beta and IL-6, did not differ between HCL patients and controls. CONCLUSION: The specific defect in IFNgamma production may play a role in the susceptibility of patients with hairy cell leukaemia towards intracellular pathogens.

The pathophysiology of the hairy cell.

HCs are clonal late B cells that are related to memory cells and display specific features of activation. Many of the distinctive features of HCs (eg, morphology, TRAP) are related to this specific activation. Many of the distinctive histologic features of HCL can be related to constitutive production of cytokines (eg, FGF, fibrosis) and to the expression/activation of adhesion receptors (eg, alpha(4)beta(1), alpha(5)beta(1) and alpha(v)beta(3) integrins, CD44v3). HCs usually have mutated IGVH genes and have no consistent or specific chromosome abnormalities (5q additions and 7q deletions in a minority). The signals that are responsible for several of the phenotypic features of HCs have been identified, but the nature of the underlying oncogenic events remains unknown.

Diagnosis, biology and treatment of hairy-cell leukaemia.

Hairy-cell leukaemia (HCL) is usually readily diagnosed by seeing typical hairy cells (HCs) in the blood film. The diagnosis is then confirmed by tartrate-resistant acid phosphatase staining, marker analysis, and bone marrow examination. HCs are clonal mature memory B cells with specific features of activation. This HC activation is responsible for many of the pathological features of the disease, including its distinctive bone marrow fibrosis, splenic red pulp invasion, and pseudo-sinus formation. Chlorodeoxyadenasine is the treatment of first choice. Deoxycoformycin and rituximab are useful for the treatment of relapsed/refractory disease. The nature of the primary oncogenic event(s) remains unknown and is the major unresolved issue in HCL.

Synaptojanin 2 is recognized by HLA class II-restricted hairy cell leukemia-specific T cells.

Hairy cell leukemia (HCL) is a chronic mature B-cell leukemia characterized by malignant B cells that have typical hairy protrusions. To characterize possible HCL-associated tumor antigens, we generated an HCL-specific and HLA class II (DPw4)-restricted proliferative CD4+ T-cell clone. To identify the target antigen of these T cells, we constructed a synthetic peptide library dedicated to bind HLA DPw4, and identified a mimicry epitope recognized by the T-cell clone. With this epitope, the recognition motif of the T-cell clone was deduced and a peptide of human synaptojanin 2 (Syn 2) was identified that stimulated the HCL-reactive T-cell clone. Both Northern and Western blot analyses showed that Syn 2 expression was increased in HCL samples compared to other B cells. Besides, the Syn 2-expressing cell line AML193, with the introduced restrictive HLA-DPw4 molecules, was recognized by the HCL-specific T-cell clone. These results indicate that Syn 2 is a target of autoreactive HCL-specific T cells. Since Syn 2 is a phosphatidylinositol 4,5-biphosphatase involved in cell growth and rearrangement of actin filaments, the increased Syn 2 expression may correlate with the disease etiology or the characteristic morphologic alterations caused by the disease.

Elucidation of the mechanisms of hairy-cell localization in tissues and the process of the bone marrow fibrosis in hairy-cell leukemia.

Hairy cell leukemia is a chronic B cell leukemia with a number of distinctive features including the unusual tissue distribution of the leukemic cells, hairy cells, and the bone marrow fibrosis. We have been working, for a number of years, on the potential mechanisms behind hairy-cell localization in tissues. In this review, it is summarized how our work has shed very important information regarding these mechanisms and led, eventually, to the full elucidation of the process of the bone marrow fibrosis in hairy cell leukemia.

Induction of apoptosis in vivo and in vitro in hairy cell leukemia treated by deoxycoformycin.

The leukemic cells of a patient with hairy cell leukemia were treated in vitro with 2'-deoxycoformycin (dCF), an inhibitor of adenosine deaminase, and deoxyadenosine (dAdo). Following this treatment, viability of the hairy cells progressively declined, and DNA fragmentation was observed. When the patient was treated with 4 mg/m2 dCF intravenously, hairy cells in his peripheral blood rapidly decreased, and a large number of TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP- biotin nick end-labeling)-positive cells were detected in a bone marrow biopsy specimen. These findings indicate that dCF induced apoptosis of hairy cells both in vivo and in vitro. Furthermore, bcl-2 mRNA was down-regulated by dCF and dAdo in the hairy cells in vitro. Our results suggest the importance of bcl-2 mRNA regulation in apoptotic cell death mediated by dCF in hairy cell leukemia.

Involvement of CD44-hyaluronan interaction in malignant cell homing and fibronectin synthesis in hairy cell leukemia.

The tissue homing of malignant hematic cells has both diagnostic and pathogenetic importance. Although such homing is incompletely understood, it generally involves cell adhesion and migration mediated by a number of adhesion receptors and cytokines. In this article, the potential importance of hyaluronan (HA) is examined for the tissue homing of hairy cells (HCs) in hairy cell leukemia (HCL). It is shown that HCs readily adhere to, and spontaneously move on, HA-coated surfaces using CD44. This indicates that activated CD44 and spontaneous movement on HA form part of the intrinsically activated phenotype of HCs. Interleukin-8 (IL-8) inhibited HC movement on HA, and this cell arrest was accompanied by increased actin polymerization and a more pronounced association of CD44 with the cytoskeleton. All of these findings are in sharp contrast to our previous observations with chronic lymphocytic leukemia cells, which are nonmotile on HA, but in response to IL-8 become polarized and motile using the receptor for HA-mediated motility rather than their apparently inactive CD44. Immunohistochemical examination of HCL tissues showed the ubiquitous presence of IL-8 and the prominence of HA in bone marrow stroma and hepatic portal tracts. This suggests that CD44-HA interactions are important in HC homing to these sites, but not to splenic red pulp or hepatic sinusoids, where HA is largely absent. Moreover, engagement of CD44 on HCs stimulates fibronectin synthesis, an observation that is likely to be relevant to the restriction of fibrosis in the disease to HC-infiltrated areas containing HA.

Chimeric monoclonal anti-CD20 antibody (rituximab)--an effective treatment for a patient with relapsing hairy cell leukaemia.

A case story is presented, describing a 46 y old man, with a relapsing hairy cell leukaemia. After treatment with monoclonal anti CD-20 antibodies (rituximab) 375mg/week, four times, a complete remission was obtained which has lasted >9 months. The rituximab treatment produced a better remission than earlier treatments with alpha-interferon and chlorodeoxyadenosine. In addition, in contrast to other treatments, no initial worsening of the pancytopenia was observed.

Treatment of hairy-cell leukemia: current views.

Although hairy-cell leukemia (HCL) is uncommon, remarkable progress has been made in the treatment of patients with this disease. Because of their unique mechanisms of action, the purine analogs, 2'-deoxycoformycin (2'-DCF) and 2-chlorodeoxyadenosine (2-CdA), are naturally targeted to lymphocytes and are cytotoxic to both resting and dividing cells. Both of these agents induce durable complete remissions (CRs) in the overwhelming majority of patients. Remarkably, equally high rates of durable CR are achieved in both untreated and previously treated patients. Furthermore, patients with large tumor burdens fare as well as those with minimal disease. Therefore, these agents have emerged as the treatments of choice for all patients with hairy-cell leukemia and have supplanted earlier treatments such as splenectomy and interferon-alpha (IFN-alpha). Since a single 7-day cycle of 2-CdA leads to excellent outcomes and is associated with few toxicities other than culture-negative fever, this agent is particularly attractive and may offer some advantages. However, given the indolent natural history of HCL, long-term follow-up study will be required to determine if one purine analog offers a survival advantage over the other.

Filgrastim for cladribine-induced neutropenic fever in patients with hairy cell leukemia.

Cladribine treatment of hairy cell leukemia (HCL) is complicated by neutropenic fever in 42% of patients despite documented infections being relatively uncommon. We performed a study of priming filgrastim followed by cladribine and then filgrastim again to determine if filgrastim would lead to a reduction of neutropenia and febrile episodes. Thirty-five patients received filgrastim and cladribine and were compared with 105 historic controls treated with cladribine alone. Cladribine was administered at 0.1 mg/kg/d by continuous infusion for 7 days. Filgrastim was administered at 5 micrograms/kg/d subcutaneously on days -3, -2, and -1 and then again after the completion of cladribine until the absolute neutrophil count (ANC) was >/=2 x 10(9)/L on 2 consecutive days (days +8, +9, etc). After filgrastim priming, the median ANC increased from 0.9 x 10(9)/L to 2.26 x 10(9)/L (2.5-fold increase), and after cladribine, the median nadir ANC in the filgrastim-treated group was 0.53 x 10(9)/L compared with 0.29 x 10(9)/L among historic controls (P =. 04). The median number of days to an ANC greater than 1.0 x 10(9)/L was 9 days in the filgrastim-treated group versus 22 days among historic controls (P < 10(-5)). The percentage of febrile patients, number of febrile days, and frequency of admissions for antibiotics were not statistically different in the two groups. Filgrastim regularly increases the ANC in patients with HCL and shortens the duration of severe neutropenia after cladribine. This phase II study, with comparison to historical controls, failed to detect any clinical advantage from the use of filgrastim and cladribine in the treatment of HCL. Accordingly, the routine adjunctive use of filgrastim with cladribine in the treatment of HCL cannot be recommended.

Treatment of hairy cell leukemia-variant with cladribine.

Hairy cell leukemia-variant (HCL-V) is an extremely rare chronic B-cell lymphoproliferative disorder clinically and morphologically distinct from classic hairy cell leukemia (HCL). HCL-V is thought to represent a hybrid between prolymphocytic leukemia and HCL, the nucleus more closely resembling a prolymphocyte and the cytoplasm a hairy cell. The clinical course of HCL-V is aggressive with short survivals. Since single courses of cladribine have profound activity in HCL, inducing durable complete responses in 91% of patients, we administered cladribine to 4 patients with HCL-V over a 7-year period. During this time interval 357 patients with classic HCL received cladribine at Scripps Clinic. Each patient received cladribine at 0.1 mg/kg per day by continuous intravenous infusion for 7 days, repeated at 28-day intervals depending on response status. The 4 patients ranged in age from 28 to 70. Two presented with B-symptoms, 1 had peripheral adenopathy, and all 4 displayed massive splenomegaly. Peripheral blood counts were notable for lymphocytosis associated with mild anemia and thrombocytopenia. Only 1 of the 4 patients had received prior treatment. Peripheral blood immunophenotypic analysis revealed monoclonal B cells with expression of CD11c in 3 patients, lack of CD25 expression in 3 patients and expression of CD103 in all but 1 patient. The number of cladribine courses administered ranged from two to five. Of these 4 patients, 1 (25%) achieved a complete response and 2 (50%) partial responses, for an overall response rate of 75%. Three patients underwent splenectomy after cladribine. Cladribine is an active agent in HCL-V albeit with a lower response rate than in classic HCL. The role of other treatment modalities, such as splenectomy, interferon-alpha, and 2'-deoxycoformycin, alone or in combination with cladribine awaits further evaluation.