Clinical Risks for Chronic Lymphocytic Leukemia.

Our understanding of risk factors for the development of chronic lymphocytic leukemia (CLL) is still incomplete and includes genetic and environmental factors. CLL is one of the most familial of all cancers, yet common high-penetrance risk alleles have not been identified. Genome-wide association studies have identified many common variants with low relative risks, whereas exome-wide rare variant analysis has implicated ATM in CLL causation. Environmental factors have also been challenging to identify given the limited understanding of the relevant time period of exposure relative to diagnosis, and the inability to quantify past exposures. Agent Orange and glyphosate herbicides have perhaps the most data to support their role. CLL is preceded by a precursor condition called monoclonal B-cell lymphocytosis (MBL), which could therefore be considered a risk factor, but which itself is likely caused by the same risk factors that ultimately give rise to CLL. Although virtually all people with CLL have a preceding MBL phase, most people with MBL will not develop CLL.

[Persistent Polyclonal B-Cell Lymphocytosis (PPBL): An Entity That Is Not What it Seems]. / Linfocitose Policlonal Persistente de Células B (LPPB): Uma Entidade que Não É o que Parece.

Persistent polyclonal B-cell lymphocytosis is a rare disease with chronic lymphocytosis of polyclonal origin, which is more frequent in mostly asymptomatic middle-aged female smokers. The hallmark of this entity is the presence of bilobed/binucleated B lymphocytes, which are polyclonal as demonstrated by immunophenotyping; an elevated IgM level is common. This disease shows, in most cases, an indolent course over many years and, although controversial, it may rarely convert to malignant lymphoma. In addition to smoking, a genetic predisposition for persistent polyclonal B-cell lymphocytosis is likely. Recurrent genetic aberrations have been described. The differential diagnosis includes non-Hodgkin's lymphoma and a clear distinction between both entities is of the utmost importance because treatment is generally not indicated in the former: instead, regular follow-up is recommended. The authors describe the case of a 46-year-old female smoker, who presented with chronic lymphocytosis, elevated IgM and circulating binucleated lymphocytes. Excluding lymphoma was important considering the unusual presentation with constitutional symptoms and splenomegaly.

A linfocitose policlonal persistente de células B é uma doença rara, caracterizada por linfocitose crónica policlonal, que ocorre mais frequentemente em mulheres fumadoras de meia-idade, que se apresentam assintomáticas ou com sintomas inespecíficos. A presença de linfócitos B binucleados é considerada a assinatura citomorfológica desta entidade. A imunofenotipagem comprova a sua origem policlonal, observando-se muitas vezes uma elevação da IgM sérica. É controverso se existe um risco aumentado de desenvolvimento de linfoma. A predisposição genética é também um fator de risco, além do tabagismo. Apesar da sua natureza policlonal, alterações genéticas recorrentes estão descritas. Na linfocitose policlonal persistente de células B a abordagem terapêutica consiste habitualmente numa vigilância regular, o que reforça a importância do seu reconhecimento. Os autores descrevem o caso de uma mulher de 46 anos, fumadora, com linfocitose crónica, IgM elevada e linfócitos binucleados. O diagnóstico diferencial com linfoma assumiu particular importância, considerando os sintomas constitucionais e esplenomegalia que apresentava.

Tumor mutational load is prognostic for progression to therapy among high-count monoclonal B-cell lymphocytosis.

ABSTRACT: High-count monoclonal B-cell lymphocytosis (HCMBL) is a precursor condition to chronic lymphocytic leukemia (CLL). We have shown that among individuals with HCMBL, the CLL-International Prognostic Index (CLL-IPI) is prognostic for time-to-first therapy (TTFT). Little is known about the prognostic impact of somatically mutated genes among individuals with HCMBL. We sequenced DNA from 371 individuals with HCMBL using a targeted sequencing panel of 59 recurrently mutated genes in CLL to identify high-impact mutations. We compared the sequencing results with that of our treatment-naïve CLL cohort (N = 855) and used Cox regression to estimate hazard ratios and 95% confidence intervals (CIs) for associations with TTFT. The frequencies of any mutated genes were lower in HCMBL (52%) than CLL (70%). At 10 years, 37% of individuals with HCMBL with any mutated gene had progressed requiring treatment compared with 10% among individuals with HCMBL with no mutations; this led to 5.4-fold shorter TTFT (95% CI, 2.6-11.0) among HCMBL with any mutated gene vs none, independent of CLL-IPI. When considering individuals with low risk of progression according to CLL-IPI, those with HCMBL with any mutations had 4.3-fold shorter TTFT (95% CI, 1.6-11.8) vs those with none. Finally, when considering both CLL-IPI and any mutated gene status, we observed individuals with HCMBL who were high risk for both prognostic factors had worse prognosis than patients with low-risk CLL (ie, 5-year progression rate of 32% vs 21%, respectively). Among HCMBL, the frequency of somatically mutated genes at diagnosis is lower than that of CLL. Accounting for both the number of mutated genes and CLL-IPI can identify individuals with HCMBL with more aggressive clinical course.

A tower of babel of acronyms? The shadowlands of MGUS/MBL/CHIP/TCUS.

With the advent of outperforming and massive laboratory tools, such as multiparameter flow cytometry and next-generation sequencing, hematopoietic cell clones with putative abnormalities for a variety of blood malignancies have been appreciated in otherwise healthy individuals. These conditions do not fulfill the criteria of their presumed cancer counterparts, and thus have been recognized as their precursor states. This is the case of monoclonal gammopathy of unknown significance (MGUS), the first blood premalignancy state described, preceding multiple myeloma (MM) or Waldenström macroglobulinemia (WM). However, in the last 2 decades, an increasing list of clonopathies has been recognized, including monoclonal B cell lymphocytosis (MBL), which antecedes chronic lymphocytic leukemia (CLL), clonal hematopoiesis of indeterminate potential (CHIP) for myeloid neoplasms (MN), and T-cell clones of uncertain significance (TCUS) for T-cell large chronic lymphocytic leukemia (LGLL). While for some of these entities diagnostic boundaries are precisely set, for others these are yet to be fully defined. Moreover, despite mostly considered of "uncertain significance," they have not only appeared to predispose to malignancy, but also to be capable of provoking set of immunological and cardiovascular complications that may require specialized management. The clinical implications of the aberrant clones, together with the extensive knowledge generated on the pathogenetic events driving their evolution, raises the question whether earlier interventions may alter the natural history of the disease. Herein, we review this Tower of Babel of acronyms pinpointing diagnostic definitions, differential diagnosis, and the role of genomic profiling of these precursor states, as well as potential interventional strategies.

Prediction of outcomes for high-count monoclonal B lymphocytosis using an epigenetic and immunogenetic signature.

ABSTRACT: Monoclonal B-cell lymphocytosis (MBL) progresses to chronic lymphocytic leukemia (CLL) requiring therapy at 1% to 5% per year. Improved prediction of progression would greatly benefit individuals with MBL. Patients with CLL separate into 3 distinct epigenetic subtypes (epitypes) with high prognostic significance, and recently the intermediate epitype has been shown to be enriched for high-risk immunoglobulin lambda variable (IGLV) 3-21 rearrangements, impacting outcomes for these patients. Here, we employed this combined strategy to generate the epigenetic and light chain immunoglobulin (ELCLV3-21) signature to classify 219 individuals with MBL. The ELCLV3-21 high-risk signature distinguished MBL individuals with a high probability of progression (39.9% and 71.1% at 5 and 10 years, respectively). ELCLV3-21 improved the accuracy of predicting time to therapy for individuals with MBL compared with other established prognostic indicators, including the CLL international prognostic index (c-statistic, 0.767 vs 0.668, respectively). Comparing ELCLV3-21 risk groups in MBL vs a cohort of 226 patients with CLL revealed ELCLV3-21 high-risk individuals with MBL had significantly shorter time to therapy (P = .003) and reduced overall survival (P = .03) compared with ELCLV3-21 low-risk individuals with CLL. These results highlight the power of the ELCLV3-21 approach to identify individuals with a higher likelihood of adverse clinical outcome and may provide a more accurate approach to classify individuals with small B-cell clones.

A tip-predominant distribution of villous intraepithelial lymphocytes is not specific to celiac disease in children with Marsh I lesions.

OBJECTIVES: To assess if the distribution of villous intraepithelial lymphocytes (IELs) in a pediatric cohort with Marsh I histopathology is specific to celiac disease (CeD). METHODS: Multicenter, retrospective case-control study between January 2001 and December 2019 in children (<18 years) with and without CeD with intraepithelial lymphocytosis and normal villous architecture. Pathology specimens were reviewed by 2 study pathologists who were blinded to the final diagnosis. Morphologic features (villous height to crypt depth ratio [Vh:Cd]) and IELs in the villous tip, top, or bottom half of the villus were quantified. RESULTS: Of the 97 children with Marsh I histopathology identified during the study period, 63 were excluded due to an insufficient number of well-oriented villous-crypt complexes or a Vh:Cd less than 2. Villous IELs were measured in 34 cases (14 CeD, 20 non-CeD controls). There was no difference between the non-CeD and CeD groups in the mean IELs at the villous tip (14.0 ± 7.1 vs 11.7 ± 6.0, P = .31), top (46.4 ± 18.4 vs 38.3 ± 10.8, P = .11), or bottom (29.8 ± 16.8 vs 28.5 ± 12.8, P = .80) half of each villus, respectively. CONCLUSIONS: The distribution of IELs in Marsh I lesions is not specific for CeD.

Characterization of Three Somatic Mutations in the 3'UTR of RRAS2 and Their Inverse Correlation with Lymphocytosis in Chronic Lymphocytic Leukemia.

Chronic lymphocytic leukemia (CLL) is a hematologic malignancy characterized by progressive accumulation of a rare population of CD5+ B-lymphocytes in peripheral blood, bone marrow, and lymphoid tissues. CLL exhibits remarkable clinical heterogeneity, with some patients presenting with indolent disease and others progressing rapidly to aggressive CLL. The significant heterogeneity of CLL underscores the importance of identifying novel prognostic markers. Recently, the RAS-related gene RRAS2 has emerged as both a driver oncogene and a potential marker for CLL progression, with higher RRAS2 expression associated with poorer disease prognosis. Although missense somatic mutations in the coding sequence of RRAS2 have not been described in CLL, this study reports the frequent detection of three somatic mutations in the 3' untranslated region (3'UTR) affecting positions +26, +53, and +180 downstream of the stop codon in the mRNA. An inverse relationship was observed between these three somatic mutations and RRAS2 mRNA expression, which correlated with lower blood lymphocytosis. These findings highlight the importance of RRAS2 overexpression in CLL development and prognosis and point to somatic mutations in its 3'UTR as novel mechanistic clues. Our results may contribute to the development of targeted therapeutic strategies and improved risk stratification for CLL patients.

Cytogenetics in the management of clonal chromosomal abnormalities of undetermined significance and persistent polyclonal B-cell lymphocytosis: Guidelines from the Groupe Francophone de Cytogénétique Hématologique (GFCH).

Acquired clonal chromosomal abnormalities (CAs) are usually considered to be disease-related. However, when a CA of this type is the only abnormality present (and especially in small clones), the clinical significance is unclear. Here, we review the literature on recurrent CAs whose significance is regularly subject to debate. Our objective was to help with their interpretation and develop guidelines for sex chromosome loss, trisomy 15, trisomy 8, deletion 20q and other isolated non-myelodysplastic neoplasm (MDS)-defining CAs. We suggest that non-MDS-defining CAs correspond to clonal hematopoiesis of indeterminate potential (CHIP) in the absence of cytopenia and clonal cytopenia of undetermined significance (CCUS) in the presence of cytopenia. Lastly, we review the literature on persistent polyclonal binucleated B-cell lymphocytosis; although usually benign, this condition may correspond to a premalignant state.

Diagnostic Utility of Bronchoalveolar Lavage Lymphocytosis in Patients with Interstitial Lung Diseases.

BACKGROUND: Interstitial lung diseases (ILDs) are extremely challenging in terms of diagnosis. Extreme bronchoalveolar lavage (BAL) lymphocytosis is thought to strongly point towards the diagnosis of hypersensitivity pneumonitis (HP). OBJECTIVES: Explore the range of different ILD that can present with BAL lymphocytosis, including cases of pronounced lymphocytosis and its diagnostic utility. METHODS: Patients with ILD that were subjected to BAL were identified retrospectively from a cohort of consecutive patients. RESULTS: BAL lymphocytosis ≥20% was recorded in 106 patients (27%), while pronounced BAL lymphocytosis ≥40% was recorded in 49 patients (12.5%). The most common diagnoses in patients with BAL lymphocytosis ≥20% and ≥40%, were HP (32.1%), connective tissue disease (CTD)-ILD (26.4%), sarcoidosis (16%), and HP (38.8%), CTD-ILD (24.5%), sarcoidosis (14.3%), respectively. CONCLUSIONS: Neither the presence nor the degree of BAL lymphocytosis can point to a specific diagnosis.

Clinico-Haematological Profile Of Chronic Lymphoproliferative Disorders In Patients Presenting With Lymphocytosis.

Objectives: To assess the spectrum and clinico-haematological profile of chronic lymphoproliferative disorders in patients presenting with lymphocytosis. METHODS: The cross-sectional, retrospective study was conducted at the Aga Khan University Hospital, Karachi, and comprised data related to cases of bone marrow aspirate and trephine from January to November 2020. Patients for whom the bone marrow was done for lymphocytosis were studied for the presence of lymphoproliferative disorders, sub-types and patients'characteristics. The diagnosis and classification were based on the World Health Organisation criteria for tumours of haematopoietic and lymphoid tissues. Data was analysed using SPSS 21. RESULTS: Of the 3,334 bone marrow specimenstested, 103(3%) were related to lymphocytosis. Of these, 84(82%) were diagnosed with lymphoproliferative disorders, while diagnosisremained undetermined in 19(18%) cases. Male:female ratio was 3.6:1 and median age was 60 years (range: 21-85 years). Constitutional symptoms were found in 61(73%) patients. Median absolute lymphocyte count was 45x109/L (range: 5.3-480). All 84(100%) patients were classified as B-cell lymphoproliferative disorder. Chronic lymphocytic leukaemia wasthe most common form, 61(73%), and 31(51%) of them presented with advanced stage disease. CONCLUSIONS: A huge majority of patients presenting with lymphocytosis had underlying lymphoproliferative disorders of which B-cell chronic lymphocytic leukaemia was found to be the most common.

Fever with atypical lymphocytosis: pearls and pitfalls in Epstein-Barr virus serology.

The heterophile antibody (also known as the Monospot) test is a useful screening tool for infectious mononucleosis (IM) resulting from primary Epstein-Barr virus (EBV) infection. However, up to 10% of patients with IM are heterophile negative. Heterophile-negative patients who have lymphocytosis or atypical lymphocytes on peripheral blood smear should be further tested for EBV serologies, which include testing for specific IgM and IgG antibodies against viral capsid antigens, early antigens and EBV nuclear antigen proteins. A diagnostic dilemma arises when the patient has clinical and laboratory features of IM, but is both heterophile negative and seronegative for IM, as illustrated in this case presentation. To avoid missed diagnoses of IM, misdiagnosis of mononucleosis-like illnesses and unnecessary testing, knowledge of test characteristics and the evolving course of EBV serologies is important to assure and inform both the physician and the patient.

Clinical course and features of persistent polyclonal B-cell lymphocytosis with BCL-6 amplification during pregnancy.

BACKGROUND: Persistent polyclonal B-cell lymphocytosis is a rare nonmalignant disorder characterized by mild persistent lymphocyte proliferation with possible evolution to aggressive lymphoma. Its biology is not well known, but it is characterized by a specific immunophenotype with rearrangement of the BCL-2/IGH gene, whereas amplification of the BCL-6 gene has rarely been reported. Given the paucity of reports, it has been hypothesized that this disorder is associated with poor pregnancy outcomes. CASE REPORT: To our knowledge, only two successful pregnancies have been described in women with this condition. We report the third successful pregnancy in a patient with PPBL and the first with amplification of the BCL-6 gene. CONCLUSIONS: PPBL is still a poorly understood clinical condition with insufficient data to demonstrate an adverse effect on pregnancy. The role of BCL-6 dysregulation in the pathogenesis of PPBL and its prognostic significance are still unknown. Evolution into aggressive clonal lymphoproliferative disorders is possible and prolonged hematologic follow-up is warranted in patients with this rare clinical disorder.

Monoclonal B-cell lymphocytosis with a non-CLL immunophenotype - Review of 34 cases.

The monoclonal B-cell lymphocytosis (MBL) introduced as new entities in the 2008 WHO classification, are defined by circulating B-cell clone < 5.109/L without organomegaly and previous and/or simultaneous lymphoproliferative disorders. The MBL were subclassified in MBL CLL type (the most frequent), MBL atypical CLL type and MBL non-CLL type (rarely reported in literature). Here the clinic, cytologic, immunologic and genetic features of MBL non-CLL type were described from a series of 34 cases. As previously reported, present cases presented immunologic and genetic similarities to MZL and could be associated to the new proposed entity CBL-MZ (clonal B-cell lymphocytosis of marginal zone origin). In addition, few cases presented similarities to splenic diffuse red pulp lymphoma (SDRPL). In conclusion, according to the literature, MBL with non-CLL type (assimilated to CBL-MZ) may be a premalignant state of MZL and/or SDRPL.