A Rare Case of Hairy Cell Leukemia with Unusual Loss of CD123 Associated with COVID-19 at the Time of Presentation

Atypical Hairy Cell Leukemia-The Current Status and Future Directions

Hairy cell leukemia (HCL) is a rare, chronic lymphoid leukemia characterized by circulating lymphocytes with pale, hair-like cytoplasmic projections, pancytopenia, marked monocytopenia, and splenomegaly. Classic HCL displays distinct morphological, immunophenotypical, and genetic features. Classic HCL cells exhibit central nuclei, abundant cytoplasm with hair-like projections, and expression of CD20, CD22, CD11c, CD103, CD25, CD123, TBX21, annexin A1 (ANXA1), FMC7, CD200, and weak cyclin D1 (CCND1). While the vast majority of classic HCL cases harbor the BRAF V600E somatic mutation, rare examples have been reported without splenomegaly, with bulky lymphadenopathy, or with an atypical morphology, immunophenotype or genotype. This review analyzes the atypical clinical, morphologic, immunophenotypic, and genetic presentations associated with classic HCL. PubMed, Web of Science, and Google Scholar were searched for articles of hairy cell leukemia, including atypical morphology, atypical immunophenotype, atypical genotype, and rare symptoms. Publications from October 2004 to December 2024 were reviewed, with additional relevant studies obtained by reviewing references from selected articles.

Morphological Clues of Acute Monocytic Leukemia in COVID-19-Induced Transient Leukoerythroblastic Reaction with Monocytosis

Viral infections, including those caused by COVID-19, can produce striking morphologic changes in peripheral blood. Distinguishing between reactive changes and abnormal morphology of monocytes remains particularly difficult, with low consensus rates reported amongst hematopathologists. Here, we report a patient who developed transient monocytosis of 11.06 × 109/L with 32% promonocytes and 1% blasts during hospitalization that was secondary to severe COVID-19 infection. Three days later, the clinical status of the patient improved and the WBC had decreased to 8.47 × 109/L with 2.2 × 109/L monocytes. Flow cytometry studies did not reveal immunophenotypic findings specific for an overt malignant population. At no time during admission did the patient develop cytopenia(s), and she was discharged upon clinical improvement. However, the peripheral blood sample containing promonocytes was sent for molecular testing with an extended next-generation sequencing myeloid panel and was positive for pathogenic NPM1 Type A and DNMT3A R882H mutations. Subsequently, despite an essentially normal complete blood count, the patient underwent a bone marrow assessment that showed acute myeloid leukemia with 77% promonocytes. This case emphasizes the critical importance of a full work up to exclude acute leukemia when classical promonocyte morphology is encountered in the peripheral blood. Promonocytes are not a part of the reactive changes associated with COVID-19 and remain specific to myeloid neoplasia.

Hairy cell leukemia 2024: Update on diagnosis, risk-stratification, and treatment-Annual updates in hematological malignancies

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 heterogenous 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 bone marrow infiltration and the presence of BRAFV600E 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 a poor prognosis, as well as HCL with TP53 mutations and HCL-V.

TREATMENT

Patients should be treated only if HCL is symptomatic. Chemotherapy with risk-adapted therapy purine analogs (PNAs) are indicated in first-line HCL patients. The use of chemo-immunotherapy combining cladribine (CDA) and rituximab (R) represents an increasingly used therapeutic approach. Management of relapsed/refractory disease is based on the use of BRAF inhibitors (BRAFi) plus R, MEK inhibitors (MEKi), recombinant immunoconjugates targeting CD22, Bruton tyrosine kinase inhibitors (BTKi), and Bcl-2 inhibitors (Bcl-2i). However, the optimal sequence of the different treatments remains to be determined.

COVID-19 in patients with classic and variant hairy cell leukemia

Hairy cell leukemia (HCL), similar to its variant HCLv, is a B-cell malignancy associated with decreased humoral immunity. We prospectively monitored the largest cohort of patients with HCL/HCLv to date (n = 503) for COVID-19 by symptoms, antibody, and polymerase chain reaction (PCR) and/or antigen positivity. Fifty percent (253 of 503) of the patients with HCL/HCLv (238 HCL and 15 HCLv) had evidence of COVID-19, with 210 (83%) testing positive by PCR or rapid-antigen test. Of the 43 patients without positive tests, all had nucleocapsid antibodies indicating COVID-19 exposure, 7 recalled no symptoms, and 36 had mild symptoms. Of the 210 who tested positive, 23, 46, 129, and 12 cases occurred in 2020, 2021, 2022, and 2023, respectively. Among them, 175 began treatment for HCL/HCLv 0.4 to 429 (median, 66) months before, and 132 had their last dose of anti-CD20 monoclonal antibody 0.2 to 229 (median, 63) months before. Two patients died, including a young woman who began rituximab 2 months after first-line cladribine before vaccine availability. Nearly all patients with HCL/HCLv recovered uneventfully from COVID-19 including those without vaccination or those with significant immunosuppression and recent treatment. However, decreased normal B cells from HCL or treatment was associated with lower spike antibody levels as a response to COVID-19 (P = .0094) and longer recovery time (P = .0036). Thus, in a large cohort of patients with HCL/HCLv and in the first to determine relationships between COVID-19 outcome and immune markers, mortality was relatively low (∼1%), sequelae were uncommon, and recovery from COVID-19 was longer if normal B cells were low after recent treatment. The trials are registered at www.clinicaltrials.gov as #NCT01087333 and #NCT04362865.

The course of patients with hairy cell leukemia during the omicron surge of the Covid-19 pandemic

In this study, we aim to explore the outcomes of Covid-19 infection in patients with Hairy cell leukemia (HCL). The cohort is based on data obtained from electronic medical records. It includes 218 consecutive patients diagnosed with HCL between 16 June 1998, and 20 September 2022, out of which the coronavirus has infected 85 patients during the Omicron surge. Out of 85 patients with HCL who were infected by Covid-19; 7 patients (8.2%) have been hospitalized, and the mortality rate was 2.3% (two patients). Thirteen of the 85 patients had been infected by Covid-19 in previous waves, including 9/13 after vaccination, and none of them developed a severe disease. Humoral immune response after three doses of the BNT162b2 mRNA vaccination regimen was evaluated in 40 patients and was attained in 67.5%. Based on multivariate analysis: unfavorable outcome was significantly more common in patients with HCL above 65 years old, who had at least one cytopenia, and with comorbidity of cardiovascular disease or asplenia. Our results indicates that the course of COVID-19 in patients with HCL during the Omicron wave has been improved relatively favorable.

Hairy Cell Leukemia: Where Are We in 2023?

PURPOSE OF REVIEW

This article summarizes the current state of knowledge of hairy cell leukemia (HCL) regarding presentation, diagnosis, therapy, and monitoring, including perspectives on emergent therapies.

RECENT FINDINGS

Over the past decade, there has been enormous progress in the understanding of the biology of HCL which has led to the development of novel therapeutic strategies. The maturation of data regarding existing management strategies has also lent considerable insight into therapeutic outcomes and prognosis of patients treated with chemo- or chemoimmunotherapy. Purine nucleoside analogs remain the cornerstone of treatment, and the addition of rituximab has deepened and prolonged responses in the upfront and relapsed setting. Targeted therapies now have a more defined role in the management of HCL, with BRAF inhibitors now having a potential in the first-line setting in selected cases as well as in relapse. Next-generation sequencing for the identification of targetable mutations, evaluation of measurable residual disease, and risk stratification continue to be areas of active investigation. Recent advances in HCL have led to more effective therapeutics in the upfront and relapsed setting. Future efforts will focus on identifying patients with high-risk disease who require intensified regimens. Multicenter collaborations are the key to improving overall survival and quality of life in this rare disease.

Concurrent COVID-19 and pneumocystis carinii pneumonia in a patient subsequently found to have underlying hairy cell leukemia

SARS-CoV-2 infection manifestation has great diversity and it becomes even greater while co-infection occurs or there is a serious underlying disease in an affected patient. In this case report, we present a case of a 71-year-old man who underwent a chest CT scan following the development of fever, weakness, and pulmonary symptoms. Chest CT scan showed segmental consolidation with centrilobular nodular infiltration, ground glass opacifications in the inferior segment of the left upper and lower lobes, and left lung pleural thickening which was atypical for either COVID-19 infection or pneumocystis carinii pneumonia but his SARS-CoV-2 PCR result was positive and he received COVID-19 treatment. His symptoms recurred after a few months with the same chest CT findings and subsequent bronchoalveolar lavage revealed the presence of pneumocystis carinii infection. Consequently, he received cotrimoxazole which caused improvement in symptoms, nonetheless splenomegaly and anemia remained in his clinical and laboratory investigation. Accordingly, bone marrow study and flow cytometry was done and confirmed the previously undiagnosed hairy cell leukemia. This case accentuates the fact that when we face atypical clinical or paraclinical features in a COVID-19 patient, we should explore for coinfection or unknown underlying diseases.

Prognosis of COVID-19 in the middle eastern population, knowns and unknowns

Since its emergence in China in 2019, the SARS-CoV-2 virus has affected all countries worldwide. The virus is easily transmitted from one person to another via infected aerosols or contaminated surfaces. Unlike its counterparts, the prognosis of COVID-19 ranges from asymptomatic to critical disease or death. Several factors play a role in determining the severity of the disease in infected patients. Among others, is the pre-existence of an underlying medical condition such as diabetes, cancer, and others. Furthermore, although children are less prone to the severe form of the COVID-19 disease, they require attention due to the report of many atypical presentations of the infection, post-asymptomatic exposure. In the Middle East, little is known about the prognosis of the SARS-CoV-2 infection in high-risk categories, notably patients with diabetes, cancer, and pregnant women. The aim of this review is to summarize the current knowledge about this group of population in the middle eastern region as well as to highlight the gap in the literature. We have found that the majority of the papers were from the Gulf countries. Although, few studies were conducted; high-risk patients appear to have an increased risk of morbidity and mortality from COVID-19 compared to their counterparts. Higher levels of inflammatory markers, C-reactive protein, erythrocyte sedimentation rate, D-dimer, and ferritin levels were also observed. Children are often asymptomatic or present with atypical presentations. More studies should be conducted to determine the clinical biomarkers of COVID-19 in high-risk categories to help in patient risk stratification and management in the middle eastern population.

Comorbidities and mortality rate in COVID-19 patients with hematological malignancies: A systematic review and meta-analysis

INTRODUCTION

The global pandemic of coronavirus disease 2019 (COVID-19) is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). It seems that there is an association between blood cancer and an increased risk of severe COVID-19. This study aimed to review the literature reporting the COVID-19 outcomes in patients with hematological malignancies.

MATERIAL AND METHODS

In this systematic review and meta-analysis, Pubmed, Embase, and Web of Science databases were searched using the following keywords: COVID-19, SARS-CoV-2, blood cancer, myeloma, lymphoma, and leukemia. All the published articles in English from January 1, 2019, until March 10, 2021 were collected and evaluated.

RESULTS

In total, 53 studies with 2395 patients were included based on inclusion criteria. Most of these studies took place in Spain (14.81%), followed by the USA (11.11%), China (9.26%), and the UK (9.26%). More than half of COVID-19 patients with hematological malignancy were male (56.73%). Oxygen therapy played an important role in COVID-19 treatment. Moreover, anticoagulant therapies such as enoxaparin and heparin were two great assists for these patients. Fever (74.24%), cough (67.64%), and fatigue (53.19%) were the most reported clinical manifestations. In addition, hypertension and dyslipidemia were the most common comorbidities. The mortality rate due to COVID-19 in patients with hematological malignancies was 21.34%.

CONCLUSION

This study demonstrated that hematologic cancer patients were more susceptible to a severe COVID-19 than patients without blood cancer. Thus, the management of COVID-19 in these patients requires much more attention, and their screening should perform regularly.

Hairy cell leukemia 2022: 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 a poor prognosis.

TREATMENT

Patients should be treated only if HCL is symptomatic. Chemotherapy with risk adapted therapy purine analogs (PNAs) are indicated in first-line HCL patients. The use of chemo-immunotherapy combining PNAs and rituximab (R) represents an increasingly used therapeutic approach. Management of relapsed/refractory disease is based on the use of BRAF inhibitors (BRAFi) plus rituximab or MEK inhibitors (MEKi), recombinant immunoconjugates targeting CD22 or Bruton Tyrosine Kinase inhibitors (BTKi). However, the optimal sequence of the different treatments remains to be determined. The Bcl2-inhibitors (Bcl-2i) can play a major role in the future.

Hairy cell leukemia and COVID-19 adaptation of treatment guidelines

Standard treatment options in classic HCL (cHCL) result in high response rates and near normal life expectancy. However, the disease itself and the recommended standard treatment are associated with profound and prolonged immunosuppression, increasing susceptibility to infections and the risk for a severe course of COVID-19. The Hairy Cell Leukemia Foundation (HCLF) has recently convened experts and discussed different clinical strategies for the management of these patients. The new recommendations adapt the 2017 consensus for the diagnosis and management with cHCL to the current COVID-19 pandemic. They underline the option of active surveillance in patients with low but stable blood counts, consider the use of targeted and non-immunosuppressive agents as first-line treatment for cHCL, and give recommendations on preventive measures against COVID-19.