Hairy cell leukemia 2018: Update on diagnosis, risk-stratification, and treatment

Clinical analysis of hairy cell leukemia: the rare indolent hematological malignancy

OBJECTIVE

To analyze the clinical features, diagnosis and treatment and prognosis of the rare hairy cell leukemia (HCL), in order to provide new references for the clinical and basic research of HCL.

METHODS

The clinical data of 17 patients with HCL admitted to Fujian Medical University Union Hospital, the Affiliated Hospital of Putian University and the First Affiliated Hospital of Gannan Medical University from January 1, 2016 to July 1, 2023 were collected and retrospectively studied, and the clinical features, diagnosis and treatment effects and prognosis of patients with HCL were analyzed. The Kaplan-Meier method was used for survival analysis. Meanwhile, the latest literature from PubMed was retrieved to systematically discuss the research progress in the diagnosis and treatment of HCL.

RESULTS

In this study, there were 11 males and 6 females, the median age at diagnosis was 59.5 (30-81) years old, and the median time from the onset of clinical symptoms or signs to diagnosis was 4.5 (0.5-28.5) months. There were 9 cases (52.94%) with lymphoma B symptoms (fever, night sweating, and weight loss), 15 cases (88.24%) were accompanied by splenomegaly (3 cases of mild splenomegaly, 4 cases of moderate splenomegaly, and 8 cases of megasplenomegaly), the positive rate of BRAFV600E mutation is 76.47% (13/17). All patients in this study were treated, of which 11 were treated with Cladribine, 3 with Interferon, 2 with FC regimen, and 1 with R-CVP regimen + Cladribine. The median follow-up time was 39 (range, 2-83) months, 3 patients died, all due to failure of chemotherapy due to disease progression. The prognosis of HCL-v patients was significantly worse than that of cHCL patients (P=0.01), and there was no significant difference in the impact of different treatment regiments on the OS of HCL patients (P=0.328).

CONCLUSION

HCL is a rare clinically indolent hematological tumor, which is sensitive to Cladribine, with the emergence of precision treatments such as the novel molecular-targeted drugs and immunotherapy also plays an indispensable role in clinical practice of HCL.

Clinical analysis of hairy cell leukemia: the rare indolent hematological malignancy

OBJECTIVE

To analyze the clinical features, diagnosis and treatment and prognosis of the rare hairy cell leukemia (HCL), in order to provide new references for the clinical and basic research of HCL.

METHODS

The clinical data of 17 patients with HCL admitted to Fujian Medical University Union Hospital, the Affiliated Hospital of Putian University and the First Affiliated Hospital of Gannan Medical University from January 1, 2016 to July 1, 2023 were collected and retrospectively studied, and the clinical features, diagnosis and treatment effects and prognosis of patients with HCL were analyzed. The Kaplan-Meier method was used for survival analysis. Meanwhile, the latest literature from PubMed was retrieved to systematically discuss the research progress in the diagnosis and treatment of HCL.

RESULTS

In this study, there were 11 males and 6 females, the median age at diagnosis was 59.5 (30-81) years old, and the median time from the onset of clinical symptoms or signs to diagnosis was 4.5 (0.5-28.5) months. There were 9 cases (52.94%) with lymphoma B symptoms (fever, night sweating, and weight loss), 15 cases (88.24%) were accompanied by splenomegaly (3 cases of mild splenomegaly, 4 cases of moderate splenomegaly, and 8 cases of megasplenomegaly), the positive rate of BRAFV600E mutation is 76.47% (13/17). All patients in this study were treated, of which 11 were treated with Cladribine, 3 with Interferon, 2 with FC regimen, and 1 with R-CVP regimen + Cladribine. The median follow-up time was 39 (range, 2-83) months, 3 patients died, all due to failure of chemotherapy due to disease progression. The prognosis of HCL-v patients was significantly worse than that of cHCL patients (P=0.01), and there was no significant difference in the impact of different treatment regiments on the OS of HCL patients (P=0.328).

CONCLUSION

HCL is a rare clinically indolent hematological tumor, which is sensitive to Cladribine, with the emergence of precision treatments such as the novel molecular-targeted drugs and immunotherapy also plays an indispensable role in clinical practice of HCL.

Pulmonary damage in a patient with hairy cell leukemia - infectious involvement or hematological disease activity? Case report

BACKGROUND

Hairy cell leukemia (HCL) is a rare indolent lymphoproliferative disease with an accumulation of mature B lymphocytes with fine reticular chromatin and cytoplasm with typical hairy-like cytoplasmic projections. Rarely, hairy cell leukemia manifests as a lung infiltration. The differential diagnosis between infection and malignant involvement with hairy cell leukemia is often challenging in such situations.

METHODS AND RESULTS

We present a 53-year-old female with an uncommon pulmonary involvement with hairy cell leukemia. In addition, we discuss the complicated differential diagnosis of pulmonary disease in patients with hairy cell leukemia and the treatment approach to these patients.

CONCLUSION

This case report describes the successful therapy management of a patient with pulmonary involvement by hairy cell leukemia. Therapy with interferon-alfa and cladribine resulted in long-term remission of the underlying disease.

Flow Cytometry of CD5-Positive Hairy Cell Leukemia

BACKGROUND AND OBJECTIVE

Hairy cell leukemia (HCL) is a chronic lymphoproliferative disorder for which diagnosis is typically straightforward, based on bone marrow morphology and flow cytometry (FC) or immunohistochemistry. Nevertheless, variants present atypical expressions of cell surface markers, as is the case of CD5, for which the differential diagnosis can be more difficult. The aim of the current paper was to describe diagnosis of HCL with atypical CD5 expression, with an emphasis on FC.

METHODS

The detailed diagnostic methodology for HCL with atypical CD5 expression is presented, including differential diagnosis from other lymphoproliferative diseases with similar pathologic features, by FC analysis of the bone marrow aspirate.

RESULTS

Diagnosis of HCL by means of FC started by gating all events based on side scatter (SSC) versus CD45 and B lymphocytes were selected from the lymphocytes gate as CD45/CD19 positive. The gated cells were positive for CD25, CD11c, CD20, and CD103, while CD10 proved to be dim to negative. Moreover, cells positive for CD3, CD4, and CD8, the three pan-T markers, as well as CD19, showed a bright expression of CD5. The atypical CD5 expression is usually correlated with a negative prognosis and thus chemotherapy with cladribine should be initiated.

CONCLUSION

HCL is an indolent chronic lymphoproliferative disorder and diagnosis is usually straightforward. However, atypical expression of CD5 renders its differential diagnosis more difficult, but FC is a useful tool that allows an optimal classification of the disease and allows initiation of timely satisfactory therapy.

Almost a Near Miss: Hairy Cell Leukemia

Hairy cell leukemia (HCL) is an infrequently encountered chronic B-lymphocyte hematological malignancy, which is found to be more prevalent in males. HCL can present with a myriad of nonspecific symptoms involving the reticuloendothelial system. Usually, patients are diagnosed after an incidental finding of pancytopenia. In the majority of cases, HCL follows an indolent course, and many patients remain asymptomatic. Treatment with nucleoside analogs is the first line of treatment and is indicated for patients with severe anemia, thrombocytopenia, neutropenia, or severe systemic symptoms. Here, we report an atypical case of a 41-year-old Hispanic female who presented with menorrhagia and iron deficiency anemia. She was diagnosed with HCL after a bone marrow biopsy demonstrated the characteristic "hairy projections."

Nanomedicine as a magic bullet for combating lymphoma

Hematological malignancy like lymphoma originates in lymph tissues and has a propensity to spread across other organs. Managing such tumors is challenging as conventional strategies like surgery and local treatment are not plausible options and there are high chances of relapse. The advent of novel targeted therapies and antibody-mediated treatments has proven revolutionary in the management of these tumors. Although these therapies have an added advantage of specificity in comparison to the traditional chemotherapy approach, such treatment alternatives suffer from the occurrence of drug resistance and dose-related toxicities. In past decades, nanomedicine has emerged as an excellent surrogate to increase the bioavailability of therapeutic moieties along with a reduction in toxicities of highly cytotoxic drugs. Nanotherapeutics achieve targeted delivery of the therapeutic agents into the malignant cells and also have the ability to carry genes and therapeutic proteins to the desired sites. Furthermore, nanomedicine has an edge in rendering personalized medicine as one type of lymphoma is pathologically different from others. In this review, we have highlighted various applications of nanotechnology-based delivery systems based on lipidic, polymeric and inorganic nanomaterials that address different targets for effectively tackling lymphomas. Moreover, we have discussed recent advances and therapies available exclusively for managing this malignancy.

Advances in the Treatment of Hairy Cell Leukemia Variant

OPINION STATEMENT

Hairy cell leukemia variant (HCL-V) is a rare B cell lymphoproliferative disorder with a clinical-pathological distinction from the classic form of hairy cell leukemia (HCL-C). HCL-V is more aggressive in nature, has a higher tendency to be refractory to conventional purine analog pharmacotherapies, and leads to a poorer prognosis. Hence, these differing features bring paramount importance to the diagnosis and management of HCL-V. While there is no genetic mutation diagnostic of HCL-V, genetic profiling efforts have identified potential therapeutic targets (i.e., MAP2K1, KDM6A, CREBBP, ARID1A, CCND3, U2AF1, KMT2C) and yielded prognostic markers (i.e., IGHV4-34 rearrangements). To date, combination chemoimmunotherapies, such as cladribine and rituximab, have shown the best results in HCL-V. Future directions include targeted therapies such as moxetumomab pasudotox, ibrutinib, trametinib, and binimetinib and potentially anti-CD22 chimeric antigen receptor T cell therapy. The purpose of this review is to provide an outline of the diagnostic approach and an update on the therapeutic advancements in HCL-V.

Antibody-drug conjugates: Resurgent anticancer agents with multi-targeted therapeutic potential

Antibody-drug conjugates (ADCs) constitute a relatively new group of anticancer agents, whose first appearance took place about two decades ago, but a renewed interest occurred in recent years, following the success of anti-cancer immunotherapy with monoclonal antibodies. Indeed, an ADC combines the selectivity of a monoclonal antibody with the cell killing properties of a chemotherapeutic agent (payload), joined together through an appropriate linker. The antibody moiety targets a specific cell surface antigen expressed by tumor cells and/or cells of the tumor microenvironment and acts as a carrier that delivers the cytotoxic payload within the tumor mass. Despite advantages in terms of selectivity and potency, the development of ADCs is not devoid of challenges, due to: i) low tumor selectivity when the target antigens are not exclusively expressed by cancer cells; ii) premature release of the cytotoxic drug into the bloodstream as a consequence of linker instability; iii) development of tumor resistance mechanisms to the payload. All these factors may result in lack of efficacy and/or in no safety improvement compared to unconjugated cytotoxic agents. Nevertheless, the development of antibodies engineered to remain inert until activated in the tumor (e.g., antibodies activated proteolytically after internalization or by the acidic conditions of the tumor microenvironment) together with the discovery of innovative targets and cytotoxic or immunomodulatory payloads, have allowed the design of next-generation ADCs that are expected to possess improved therapeutic properties. This review provides an overview of approved ADCs, with related advantages and limitations, and of novel targets exploited by ADCs that are presently under clinical investigation.

Management of Relapsed Hairy Cell Leukemia: A Systematic Review of Novel Agents and Targeted Therapies

BACKGROUND

Hairy cell leukemia (HCL) responds well to purine analogs with an overall median relapse free survival of 11-16 years. Most patients can be retreated with the same or a different purine analog however a subset of patients will become resistant or develop cumulative toxicities. Novel agents such as Vemurafenib (BRAF kinase inhibitor), Bendamustine/Rituximab (BR), Moxetumomab pasudotox (anti CD-22 recombinant immunotoxin) and Ibrutinib have emerging roles in patients with relapsed HCL.

METHODS

Five databases (PubMed, Embase, Cochrane Library, Web of Science and ClinicalTrials.gov) were searched using the following search terms: "hairy cell leukemia" or "leukemia, hairy cell" AND "relapse" or "recurrence". We included only prospective clinical trials with outcome data.

RESULTS

Vemurafenib monotherapy was evaluated in two separate arms of a phase 2 trial. In the US arm (n=24), the ORR was 100% (CR 42%; PR 58%). In the Italian arm (n=26), the ORR was 96% (CR 35%; PR 62%). In a phase 2 study (n=25), the combination of vemurafenib and rituximab showed CR of 100%. The combination of BR achieved an ORR of 100% whereas CR was 50% and 67% at a bendamustine dose of 70mg/m² (n=6) and 90 mg/m² (n=6) respectively. In a phase 3 trial, moxetumomab pasudotox (n=80) had an ORR of 75% (CR 41%). Single agent Ibrutinib (n=37) had an ORR of 54%. Therapies were generally well tolerated.

CONCLUSION

Novel agents have good efficacy in HCL in patients with multiple relapses.

Cladribine transfer into human milk: A case report

BACKGROUND

Cladribine is an antimetabolite used for the treatment of relapsing-remitting multiple sclerosis. At present, there are no data available on its use in breastfeeding mothers and its transfer in human milk.

OBJECTIVE

We present a case of a lactating mother who donated her milk samples to study the transfer of cladribine following a 20-mg oral dose.

METHODS

Analysis was done using liquid chromatography-mass spectrometry.

RESULTS

The relative infant dose calculated in this study was 3.06%.

CONCLUSION

This is the first case report suggesting the transfer of cladribine in human milk in measurable quantities. However, caution should be advised during lactation.

A rare case of hairy cell leukemia with co-expression of CD5 and cyclin D1: A diagnostic pitfall

Hairy cell leukemia (HCL) is an uncommon chronic B-cell lymphoproliferative disease with an indolent course. It mainly occurs in elderly men, although abdominal lymphadenopathy is rare. HCL cells are mostly found in the bone marrow, peripheral blood, and spleen and typically express CD11c, CD20, CD25 and CD103. We present a case of HCL with a novel immunophenotype. A 48-year-old woman presented with pancytopenia and splenomegaly. The diagnosis was HCL with lymph node infiltration. Unlike previously described HCL cases, the current case showed strong expression of CD5 and cyclin D1 in the lymph nodes. The patient underwent cladribine chemotherapy, and the leukocyte count increased during and after treatment. The 8-month follow-up revealed that she had recovered well. This case highlights the distinctive immunophenotype of HCL infiltrating the lymph nodes and the potential misdiagnosis of HCL as mantle cell lymphoma. It also adds to our limited understanding of HCL.

A population-based study of hairy cell leukemia over a period of 20 years

There are limited population-based studies of hairy cell leukemia (HCL), a rare chronic lymphoproliferative disorder of B-cells. We conducted a population-based study that included all patients diagnosed with HCL between 1996 and 2016 in Western Normandy. Recorded data focused on medical history, clinical presentation, biological results, treatment modalities in the first line and in relapsed/refractory patients and the occurrence of secondary malignancies. One hundred and twenty-three HCL patients were registered in the database. HCL represented 0.7% of all malignant hematological disorders and 3.0% of all leukemia. The overall age-standardized incidence ratio (SIR) was 0.39/100,000 inhabitants in men and 0.09/100,000 in women, and it remained stable over the 20-year period analyzed. One hundred and seven patients (88%) received first-line treatment, 33 patients (27%) received at least 2 lines of treatment and 14 patients (11%) received more than 2 lines. Cladribine used as first-line treatment induced a high hematological complete response (HCR) rate of 92%. The median overall survival (OS) was over 15 years, with 5-year and 10-year survival rates of 84% and 70.5%. No significant differences in OS were observed between men and women, between the calendar periods studied or between patients who received a single line treatment with IFN-α or PNA. The risk of relapse was higher with IFN-α treatment, requiring subsequent treatments in that patients. The time to next treatment (TTN) tends to be longer for PNAs compared to IFN-α even if difference is not significant. Secondary cancers were observed in 9/123 patients (7.3%) with solid tumors in 8 patients and hematological malignancy in one patient. Our data confirm in real life that single courses of cladribine administered to patients with HCL induce high response rates, the majority of which are HCR. Relapses seem less frequent than with IFN-α and the administration schedule is less restrictive for the patients. The emergence of chemo-immunotherapy and the development of effective new drugs such as recombinant immunotoxins and BRAF targeting will offer new possibilities in the management of HCL patients.

Telomere Length and Hematological Disorders: A Review

Telomeres compose the end portions of human chromosomes, and their main function is to protect the genome. In hematological disorders, telomeres are shortened, predisposing to genetic instability that may cause DNA damage and chromosomal rearrangements, inducing a poor clinical outcome. Studies from 2010 to 2019 were compiled and experimental studies using samples of patients diagnosed with hematological malignancies that reported the size of the telomeres were described. Abnormal telomere shortening is described in cancer, but in hematological neoplasms, telomeres are still shortened even after telomerase reactivation. In this study, we compared the sizes of telomeres in leukemias, myelodysplastic syndrome and lymphomas, identifying that the smallest telomeres are present in patients at relapse. In conclusion, the experimental and clinical data analyzed in this review demonstrate that excessive telomere shortening is present in major hematological malignancies and its analysis and measurement is a crucial step in determining patient prognosis, predicting disease risk and assisting in the decision for targeted therapeutic strategies.

Antibody-drug conjugates for previously treated aggressive lymphomas: focus on polatuzumab vedotin

INTRODUCTION

Antibody-drug conjugates (ADCs) are immunoconjugates and comprise a monoclonal antibody that is chemically attached to a cytotoxic drug (or payload) via a stable chemical linker. Since the approval of the first ADC in 2000, there are now nine different approved agents and over 100 ADCs in the drug-development pipeline.

AREAS COVERED

This review briefly describes the ADCs approved for treatment of lymphoma and their distinguishing factors in terms of target, linker and payload. The clinical implications of the use of ADCs are also considered. Here, we focus on polatuzumab vedotin, an ADC targeted to CD79b, which is approved for the treatment of patients with relapsed/refractory diffuse large B-cell lymphoma (R/R DLBCL) who have received at least one (EU approval) or two (US approval) prior therapies and are not eligible for bone marrow transplantation. The characteristics of polatuzumab vedotin are discussed and clinical data are presented. The future of polatuzumab vedotin clinical development, and ADCs in general, are also considered.

EXPERT OPINION

ADCs represent a significant advance in the treatment of lymphoma. Polatuzumab vedotin has shown clinical efficacy and a tolerable safety profile in both first-line and R/R DLBCL; future studies are planned to further investigate this ADC.

Vemurafenib-induced pancreatitis in a patient with recurrent hairy cell leukaemia

Recent studies have shown that BRAF inhibitors, such as vemurafenib, are effective in inducing long periods of remission in relapsed hairy cell leukaemia. Acute pancreatitis is one of the rare complications that is reported with vemurafenib use. As severe pancreatitis can be life threatening, physicians should be vigilant of this side effect and promptly treat patients that develop clinical signs and symptoms while receiving vemurafenib. We present an interesting case of vemurafenib-induced pancreatitis that not only resolved but also did not recur after reintroduction of the drug at a reduced dose.

Moxetumomab pasudotox for hairy cell leukemia: preclinical development to FDA approval

Moxetumomab pasudotox (MP) is an immunotoxin that recently received US Food and Drug Administration (FDA) approval for the treatment of hairy cell leukemia (HCL) that has failed at least 2 prior lines of therapy, including a purine analog. MP is a recombinant immunotoxin that consists of an anti-CD22 immunoglobulin variable domain genetically joined to Pseudomonas exotoxin (PE38). Unlike most antibody-drug conjugates, which use a chemical linker, recombinant DNA techniques are used to produce MP. MP and its predecessor, BL22, were initially developed to treat non-Hodgkin lymphoma, acute lymphoblastic leukemia, and HCL. However, MP was found to be particularly effective in HCL due to the high level of CD22 cell-surface expression. The recent pivotal phase 3 trial of MP in relapsed/refractory HCL demonstrated a durable complete remission rate of 30%, and 85% of complete responders achieved minimal residual disease negativity, which is associated with improved disease-free survival outcomes in HCL. In addition to an exceptional depth of response, MP appears to be less immunosuppressive than purine analogs. MP is generally well tolerated but has unique toxicities, including capillary leak syndrome and hemolytic uremic syndrome, which are poorly understood. This review will encompass the preclinical and clinical development of MP, with particular attention to its current indication in HCL.

Moxetumomab Pasudotox: Clinical Experience in Relapsed/Refractory Hairy Cell Leukemia

BACKGROUND

Moxetumomab pasudotox is a promising new therapy for the treatment of patients with relapsed/refractory hairy cell leukemia (R/R HCL), but practical guidance relating to its administration is limited.

OBJECTIVES

This article describes clinical guidelines for the administration of moxetumomab pasudotox to patients with R/R HCL and presents related case studies.

METHODS

A limited review of the literature on HCL was undertaken.

FINDINGS

Nursing care of patients prescribed moxetumomab pasudotox includes monitoring clinical and laboratory parameters, managing side effects, being aware of signs of serious side effects, and maintaining patient hydration during administration.

Analysis of a cohort of 279 patients with hairy-cell leukemia (HCL): 10 years of follow-up

In total, 279 patients with hairy-cell leukemia (HCL) were analyzed, with a median follow-up of 10 years. Data were collected up to June 2018. We analyzed responses to treatment, relapses, survival, and the occurrence of second malignancies during follow-up. The median age was 59 years. In total, 208 patients (75%) were treated with purine analogs (PNAs), either cladribine (159) or pentosatin (49), as the first-line therapy. After a median follow-up of 127 months, the median overall survival was 27 years, and the median relapse-free survival (RFS) was 11 years. The cumulative 10-year relapse incidence was 39%. In patients receiving second-line therapy, the median RFS was 7 years. For the second-line therapy, using the same or another PNA was equivalent. We identified 68 second malignancies in 59 patients: 49 solid cancers and 19 hematological malignancies. The 10-year cumulative incidences of cancers, solid tumors, and hematological malignancies were 15%, 11%, and 5.0%, respectively, and the standardized incidence ratios were 2.22, 1.81, and 6.67, respectively. In multivariate analysis, PNA was not a risk factor for second malignancies. HCL patients have a good long-term prognosis. PNAs are the first-line treatment. HCL patients require long-term follow-up because of their relatively increased risk of second malignancies.

Erdheim-Chester Disease and Small Lymphocytic Lymphoma Collision Tumour Presenting as a Perirenal Mass

Background

Erdheim-Chester disease is a rare histiocytic neoplasm associated with MAPK pathway mutations. Disease manifestation is variable often involving many different organs, mainly bone, retroperitoneum, the heart, and the central nervous system. Histological findings include foamy histiocytes in a fibrous stroma with scattered inflammatory infiltrate. Histiocytes are CD68 positive and S100 negative. Case Report. We report a case of Erdheim-Chester disease associated with small lymphocytic lymphoma presenting as a perirenal mass with a review of the recent literature.

Conclusions

Erdheim-Chester disease rarely can be associated with other cancers, namely myeloid neoplasms. We report a case of Erdheim-Chester disease presenting with small lymphocytic lymphoma as a perirenal mass. The association of Erdheim-Chester disease with lymphoproliferative disorders needs to be elucidated.

Adverse event rates and economic burden associated with purine nucleoside analogs in patients with hairy cell leukemia: a US population-retrospective claims analysis

Background

Purine nucleoside analogs (PNAs) are the recommended first-line treatment for patients with hairy cell leukemia (HCL), but they are associated with adverse events (AEs). Due to a lack of real-world evidence regarding AEs that are associated with PNAs, we used commercial data to assess AE rates, AE-related health care resource utilization (HCRU), and costs among PNA-treated patients with HCL. Adults aged ≥18 years with ≥2 claims for HCL ≥30 days apart from 1 January 2006 through 31 December 2015 were included. Included patients had ≥1 claim for HCL therapy (cladribine ± rituximab or pentostatin ± rituximab [index date: first claim date]) and continuous enrollment for a ≥ 6-month baseline and ≥ 12-month follow-up period. Patient sub-cohorts were based on the occurrence of myelosuppression and opportunistic infections (OIs). Generalized linear models were used to compare HCRU and costs.

Results

In total, 647 PNA-treated patients were identified (mean age: 57.1 years). Myelosuppression and OI incidence were 461 and 42 per 1000 patient-years, respectively. Adjusted results indicated that those with myelosuppression had higher rates of hospitalization (47.4% vs 12.4%; P < .0001) and incurred higher mean inpatient costs ($23,517 vs $12,729; P = .011) and total costs ($57,325 vs $34,733; P = .001) as compared with those without myelosuppression. Similarly, patients with OIs had higher rates of hospitalization (53.8% vs 30.8%; P = .025) and incurred higher mean inpatient costs ($21,494 vs $11,229; P < .0001) as compared with those without OIs.

Conclusions

PNA therapy is highly effective but associated with significant toxicities that increase costs; these findings indicate a need for therapies with improved toxicity profiles and better risk stratification of patients at risk of developing myelosuppression and OIs.

Disseminated Histoplasmosis with Concurrent Hairy Cell Leukemia

Histoplasmosis is an endemic fungal infection that can lead to disseminated disease, especially in immunosuppressed patients. Hairy cell leukemia is a rare, slow-growing hematological malignancy. Concurrence of histoplasmosis and hairy cell leukemia is extremely rare. We describe a 69-year-old male who presented with fever, dry cough, pancytopenia, multiple pulmonary nodules, and massive splenomegaly. Histoplasma urinary antigen was positive and disease was confirmed by biopsy of lung lesions. Peripheral smear showed 'hairy cells', and bone marrow biopsy revealed findings of hairy cell leukemia. The patient was treated with intravenous amphotericin, followed by oral itraconazole. After the initial treatment of infection, treatment for hairy cell leukemia was started with cladribine. We will discuss the principles of treating disseminated histoplasmosis in the setting of immunosuppression, and hairy cell leukemia with coexisting infection.

Difference of genomic copy numbers alterations between hairy cell leukemia-variant and classical hairy cell leukemia: a pilot retrospective study in Chinese

Background: Hairy cell leukemia (HCL) is a rare chronic B-cell lymphoproliferative disorder. It has two pathological subtypes: classical HCL (HCL-C) and HCL-variant (HCL-V). HCL-C and HCL-V are distinct in morphology and immunophenotype. Their differentiation is important for patient management and clinical outcome, with HCL-V responding poorly to conventional HCL treatments. Recently, whole genomic sequencing has been used to identify the difference between HCL-C and HCL-V and mutation of BRAF^V600E has been proved to be a molecular hallmark of HCL-C. However, BRAF inhibitors were not effective in all HCL-C cases and HCL-V seems be lack of the high-frequency mutations. Therefore, it is necessary to compare the genomic changes between HCL-C and HCL-V by high-resolution studies, especially in Chinese population, the genomic alterations of HCL have rarely be reported. Methods: In this study, the clinical features of a total of 18 Chinese HCL patients were described. Single nucleotide polymorphism (SNP) array analysis was performed to evaluate the genomic copy number alterations (CNA) and copy neutral loss of heterozygosity (CN-LOH) on six HCL-Vs with CD25^-/BRAF^V600E- and four HCL-Cs with CD25⁺/BRAF^V600E+. Results: A total of 24 CNAs including seven chromosomal gains and 17 chromosomal losses, and 22 CN-LOHs were revealed. Five of the six cases of HCL-V showed 15 CNAs including four cryptic chromosomal gains and 11 chromosomal losses. Overlapping regions involving micro-deletion of chromosome 2q13 and large chromosomal loss of 14q were showed in HCL-V. In HCL-C, a total of nine CNAs were revealed in three of the four cases including three chromosomal gains and six chromosomal losses. No overlapping area was observed among the CNVs. 15 CN-LOHs were showed in five of the six cases of HCL-V and seven CN-LOHs was demonstrated in all of the four HCL-Cs. Conclusions: Comparing to Westerners, a relatively higher proportion of HCL-V in all HCL is observed in this study. CNAs and CN-LOHs were common in both HCL-V and HCL-C but the CNAs were different in them. HCL-C was characterized with the higher ratio of large chromosomal changes but lacked of recurrent CNAs, while HCL-V was presented with the higher incidence of cryptic CNAs and recurrent CNAs involving tumor-associated genes. It is necessary to further investigate the association of the genes, such as NPHP1 and TRAF3 genes, and HCL-V in the future study.

Acute profound sensorineural hearing loss as the initial manifestation of Hairy Cell Leukemia, Case Report and literature review

INTRODUCTION

Hematologic diseases are rarely present with sudden hearing loss as an initial symptom. Although the precise cause of sudden sensorineural hearing loss has not been identified, several pathophysiological mechanisms have been proposed. However, a variety of hematologic diseases are among the causes of sudden onset deafness. This article represents the first reported case of Hairy cell leukemia (HCL) which presented with acute unilateral profound sensorineural hearing loss as an inital mainfestation.

PRESENTATION OF CASE

A 41-year-old man presented with unilateral sudden hearing loss for one day's duration was found to have HCL during a worked up for his hearing loss. The disease worsened, and there was no improvement in his hearing.

DISCUSSION

Sudden sensorineural hearing loss can rarely be seen as a paraneoplastic occurrence.Very few cases have been reported in the literature. It has been reported as a presenting symptom of leukemia in numerous clinical and histopathological reports concerning the hearing loss in hematologic diseases. Our case is an example of such a rare incidence.

CONCLUSION

The purpose of this study is to draw physicians' attention to the possible association between acute sensorineural hearing loss to HCL, and to highlights permanent deafness as a complication secondary to HCL. Furthermore, it is important to increase awareness on early diagnosis and treatment that may improve treatment outcomes.

Variant form of hairy cell leukemia

Mature lymphoid B-cell proliferations with hairy cells represent heterogeneous entities where specific diagnosis is difficult but important since it impacts therapeutic management. The clinical cases of variant hairy cell leukemia reported herein illustrate the persistence of a clear interest in the use of splenectomy as a therapeutic alternative. Furthermore, ibrutinib appears to be a promising treatment in patients with relapsed/refractory disease.

Outcome of hairy cell leukemia patients treated with cladribine - a 10-year single-center experience in Pakistan

INTRODUCTION AND OBJECTIVE

Hairy cell leukemia is an uncommon, indolent B-cell lymphoproliferative disorder. Therapy with cladribine (2-chlorodeoxyadenosine) is able to induce complete remission (CR) in the majority of patients after a single course of treatment. We report the outcomes of patients treated at Aga Khan University Hospital, Karachi, Pakistan.

METHODS

This was a retrospective review. Medical records of patients were used to collect data.

RESULTS

A total of 21 patients with hairy cell leukemia were treated with cladribine. All patients achieved an initial CR. Four patients (19%) required hospitalization and therapy for neutropenic fever. Six patients (29%) relapsed at a median of 48 months. All 6 patients were treated for relapse, out of which 4 achieved CR, 1 had partial response and 1 had refractory disease. The overall survival rate was 90.5%, with a median follow-up of 35 months.

CONCLUSION

A single course of cladribine is able to induce CR in a vast majority of patients. Unfortunately, relapse is not uncommon. Patients who relapse can be successfully retreated with cladribine. Cladribine has impressive efficacy and a favorable acute and long-term toxicity profile when administered to patients with HCL.

No Loose Ends: A Review of the Pharmacotherapy of Hairy Cell and Hairy Cell Leukemia Variant

Objective: To review the literature for the treatment of classical and variant hairy cell leukemia (HCL, HCLv), evaluating efficacy, safety, and supportive care involved in the use of purine analogues (PAs), interferon, BRAF inhibitors, monoclonal antibodies, Bruton's tyrosine kinase inhibitors, and new immunotoxin, moxetumomab pasudotox-tdfk (MPT). An electronic literature search of PubMed (January 1958 to January 2019) was conducted in PubMed using the MESH terms hairy cell leukemia, hairy cell leukemia variant, cladribine, pentostatin, rituximab, interferon, vemurafenib, moxetumomab pasudotox. Study Selection and Data Extraction: Studies written in the English language were considered for this article. The significance of each article was determined by authors independently. Data Synthesis: HCL and HCLv are rare B-cell lymphoproliferative disorders, each with distinct biologies. Symptoms are characterized by pancytopenia and splenomegaly. Initial treatments for HCL were suboptimal, leading to minimal and transient remissions. PAs significantly improved outcomes, inducing remission in most patients. However, those with purine-resistant disease were left with a dearth of options, leading to implementation of vemurafenib for BRAF V600 mutated disease and chemoimmunotherapy with rituximab. Despite these advances, some HCL and a majority of HCLv patients experience relapse. Newer targeted agents offer promise for relapsed and refractory patients, including the recently approved MPT. Relevance to Patient Care and Clinical Practice: This review provides a comprehensive update on the pharmacological management of HCL and HCLv for clinicians who encounter patients with this rare disease. Conclusion: HCL and HCLv are uncommon lymphoid neoplasms that lead to a characteristic constellation of symptoms. The emergence of PAs and novel targeted agents have improved the likelihood and durability of responses for these patients.

Cortactin expression in non-Hodgkin B-cell lymphomas: a new marker for the differential diagnosis between chronic lymphocytic leukemia and mantle cell lymphoma

Cortactin is a cytoskeletal-remodeling adaptor protein, playing an oncogenic role in solid tumors. Little is known on cortactin expression in non-Hodgkin B-cell lymphomas (B-NHLs). The present study aimed to characterize cortactin expression in B-NHLs and to assess its role in the differential diagnosis of such entities. Cortactin protein expression was first assessed by immunohistochemistry in a series of 131 B-NHLs, including B-cell chronic lymphocytic leukemia (CLL; n = 17), mantle cell lymphoma (MCL; n = 16), follicular lymphoma (FL; n = 25), marginal zone lymphoma (MZL; n = 30), hairy cell leukemia (HCL; n = 10), splenic diffuse red pulp small B-cell lymphomas (SDRPBL; n = 3), and diffuse large B-cell lymphoma (DLBCL; n = 30) cases. Cortactin was expressed in 14 of 17 CLLs, 10 of 10 HCLs, and 22 of 30 DLBCLs. MCLs, SDRPBLs, most FLs, and MZLs were cortactin negative. The immunohistochemical results were in keeping with in silico gene expression data. In CLL, cortactin positivity did correlate with LEF1 and CD200 expression, and the combined positivity for ≥2 markers strongly predicted CLL diagnosis. Such preliminary data suggested a role for cortactin in the differential diagnosis between CLL and MCL. This hypothesis was confirmed in a large validation set of 112 CLLs (n = 55) and MCLs (n = 57), which also disclosed rare cortactin-expressing MCLs. The immunohistochemical and gene expression results were sustained by flow cytometry and Western blot analysis on CLL and MCL cell lines. In conclusion, cortactin is mainly expressed in subsets of CLL and DLBCL and in HCL. Cortactin may represent a novel marker for the differential diagnosis between CLL and MCL.

Hairy cell leukemia 2018: Update on diagnosis, risk-stratification, and treatment

Disease overview

Hairy cell leukemia (HCL) and HCL‐like disorders, including HCL variant (HCL‐V) and splenic diffuse red pulp lymphoma (SDRPL), are a very heterogeneous group of mature lymphoid B‐cell disorders, characterized by the identification of hairy cells, a specific genetic profile, a different clinical course and the need for appropriate treatment.

Diagnosis

Diagnosis of HCL is based on morphological evidence of hairy cells, an HCL immunologic score of 3 or 4 based on the CD11C, CD103, CD123, and CD25 expression, the trephine biopsy which makes it possible to specify the degree of tumoral medullary infiltration and the presence of BRAF V600E somatic mutation.

Risk stratification

Progression of patients with HCL is based on a large splenomegaly, leukocytosis, a high number of hairy cells in the peripheral blood and the immunoglobulin heavy chain variable region gene mutational status. VH4‐34 positive HCL cases are associated with poor prognosis

Risk adapted therapy

Purine analogs (PNA) are indicated in symptomatic first line HCL patients. The use of PNA followed by rituximab represents an alternative option.

Management of progressive or refractory disease

It is based on the use of BRAF inhibitors associated or not with MEK inhibitors, recombinant immunoconjugates targeting CD22 or BCR inhibitors.