Prognostic and Predictive Significance of Smudge Cell Percentage on Routine Blood Smear in Chronic Lymphocytic Leukemia

Pseudohyperkalemia in chronic lymphocytic leukemia: Prevalence, impact, and management challenges

The term pseudohyperkalemia refers to a false elevation in serum potassium levels due to potassium release from cells in vitro. Falsely elevated potassium levels have been reported in patients with thrombocytosis, leukocytosis, and hematologic malignancies. This phenomenon has been particularly described in chronic lymphocytic leukemia (CLL). Leukocyte fragility, extremely high leukocyte counts, mechanical stress, higher cell membrane permeability related to an interaction with lithium heparin in plasma blood samples, and metabolite depletion due to a high leukocyte burden have been reported to contribute to pseudohyperkalemia in CLL. The prevalence of pseudohyperkalemia is up to 40%, particularly in the presence of a high leukocyte count (>50 × 109/L). The diagnosis of pseudohyperkalemia is often overlooked, which may result in unnecessary and potentially harmful treatment. The use of whole blood testing and point-of-care blood gas analysis, along with thorough clinical evaluation, may help differentiate between true and pseudohyperkalemic episodes.

Death of tonsillar B cells by NETosis

Regulating B cell death is essential for generating antibodies and maintaining immune tolerance. B cells can die by apoptosis, and we report that human tonsil B cells, but not peripheral blood B cells also die by NETosis. This cell death is density-dependent, characterized by the loss of cell and nuclear membrane integrity, release of reactive oxygen species, and chromatin decondensation. Tonsil B cells secrete high levels of TNF, and inhibiting TNF prevented chromatin decondensation. By in situ fluorescence microscopy, B cell NETosis, as identified by the hyper citrullination of Histone-3, was localized to the light zone (LZ) of germinal centers in normal tonsil and overlapped with the B cell marker CD19/IgM. We propose a model in which stimulation of B cells in the LZ induces NETosis, driven in part by TNF. We also provide evidence that NETosis of tonsil B cells may be inhibited by an unidentified factor in tonsil. The results describe a previously unidentified form of B cell death and suggest a new mechanism to maintain B cell homeostasis during immune responses.

Smudge cells percentage on blood smear is a reliable prognostic marker in chronic lymphocytic leukemia

Objective

We evaluated the relevance of using the smudge cell percentage in the blood smear as a prognostic marker in CLL.

Methods

In this prospective study, 42 untreated Senegalese patients with CLL were enrolled. The diagnosis was established, based on the peripheral blood count and flow cytometry using the Matutes score. Cytogenetic aberrations, assessed by fluorescence in situ hybridization (FISH), were available for 30 patients, while the immunoglobulin heavy chain genes (IGVH) mutation status was performed by next-generation sequencing (NGS) in 24 patients. The SC percentage was determined in the blood smear, as previously described. Statistical analyses were executed using the GraphPad Prism 8.

Results

The mean age was 63 years (48 - 85) and the male: female sex ratio was 4.66. A low SC (< 30%) percentage was correlated with Binet stage B/C (p = 0.0009), CD38 expression (p = 0.039), unmutated IGVH status (p = 0.0009) and presence of cytogenetic abnormalities (for del 13q, p = 0.0012, while for other cytogenetic aberrations, p = 0.016). An inverse correlation was found between the SC percentage and the absolute lymphocyte count (r = -0.51) and patients with higher percentage of SCs had a prolonged survival. However, there was no correlation between the SC percentage and age (p = 0.41) or gender (median, 19% for males vs. 20% for females; p = 0.76).

Conclusion

When less than 30%, the SC was associated with a poor prognosis in CLL. Easy and affordable, the percentage of SCs in a blood smear could be a reliable prognostic marker, accessible to all CLL patients, mainly those in developing countries.

The future of laboratory testing in chronic lymphocytic leukaemia

Chronic lymphocytic leukaemia (CLL) is a malignant lymphoproliferative disorder characterised by the accumulation of dysfunctional B-lymphocytes in the blood and lymphoid tissues. It is a clonally complex disease with a high degree of both intra-tumoural and inter-patient heterogeneity. This variability leads to a wide range of clinical outcomes and highlights the critical need for accurate prognostic tests in CLL. With the advent of a range of new targeted agents for CLL in recent years, there is also a clinical need for improved predictive tests to therapy. This review of laboratory testing in CLL focuses on emerging technologies for prognostication including single nucleotide polymorphism microarray for karyotypic analysis, targeted next generation sequencing analysis of the immunoglobulin heavy chain variable region gene as well as genes recurrently mutated in the disease such as TP53, and detection of minimal residual disease.

Smudge Cells in Chronic Lymphocytic Leukemia: Pathophysiology, Laboratory Considerations, and Clinical Significance

Chronic lymphocytic leukemia (CLL) is the most commonly encountered leukemia in the clinical laboratory. Cytoskeletal defects in CLL lymphocytes can result in the formation of up to 75% smudge cells (SCs) during blood film preparation. Failure to account for these damaged lymphocytes in the white blood cell (WBC) differential diminishes the accuracy and reproducibility of the results. Lacking clear practice standards on handling SCs in CLL, different laboratories may employ different methods to mitigate SC-induced errors. This review explores the pathophysiology of SCs, their effect on WBC differentials in CLL, and how these results can impact clinical decisions. The pros and cons of various SC corrective methods are described to assist laboratories in developing an optimized protocol to reduce errors and inconsistencies in WBC differentials. Finally, the potential utility of SC enumeration as an indicator of CLL prognosis is discussed in terms of laboratories with differing access to technology.

Peripheral Blood Smear Findings of COVID-19 Patients Provide İnformation about the Severity of the Disease and the Duration of Hospital Stay

Background

Data about the morphological changes in peripheral blood smears during COVID-19 infection and their clinical severity association are limited. We aimed to examine the characteristics of the cells detected in the pathological rate and/or appearance and whether these findings are related to the clinical course by evaluating the peripheral blood smear at the time of diagnosis in COVID-19 patients.

Methods

Clinical features, laboratory data, peripheral blood smear of fifty patients diagnosed with COVID-19 by PCR was evaluated at diagnosis. Peripheral smear samples of the patients were compared with the age and sex-matched 30 healthy controls. Pictures were taken from the patient’s peripheral blood smear. Patients were divided into two groups. Mild and severe stage patient groups were compared in terms of laboratory data and peripheral smear findings. The relationship between the laboratory values of all patients and the duration of hospitalization was analyzed.

Results

The number of segmented neutrophils and eosinophils were low, pseudo-Pelger-Huet, pseudo-Pelger-Huet/mature lymphocyte ratio, atypical lymphocytes, monocytes with vacuoles, bands, and pyknotic neutrophils rates were higher in the peripheral blood smear of the patient group (p <0.05). Increased pseudo-Pelger-Huet anomaly, pseudo-Pelger Huet/mature lymphocyte ratio, a decreased number of mature lymphocytes, and eosinophils in peripheral blood smear were observed in the severe stage patients (p <0.05). A negative correlation was observed between hospitalization duration and mature lymphocyte and monocytes with vacuoles rates (p <0.05).

Conclusion

A peripheral blood smear is an inexpensive, easily performed, and rapid test. Increased Pseudo-Pelger-Huet anomaly/mature lymphocyte rate suggests a severe stage disease, while high initial mature lymphocyte and monocytes with vacuoles rates at the time of diagnosis may be an indicator of shortened duration of hospitalization.

Prognostic models for newly-diagnosed chronic lymphocytic leukaemia in adults: a systematic review and meta-analysis

BACKGROUND

Chronic lymphocytic leukaemia (CLL) is the most common cancer of the lymphatic system in Western countries. Several clinical and biological factors for CLL have been identified. However, it remains unclear which of the available prognostic models combining those factors can be used in clinical practice to predict long-term outcome in people newly-diagnosed with CLL.

OBJECTIVES

To identify, describe and appraise all prognostic models developed to predict overall survival (OS), progression-free survival (PFS) or treatment-free survival (TFS) in newly-diagnosed (previously untreated) adults with CLL, and meta-analyse their predictive performances.

SEARCH METHODS

We searched MEDLINE (from January 1950 to June 2019 via Ovid), Embase (from 1974 to June 2019) and registries of ongoing trials (to 5 March 2020) for development and validation studies of prognostic models for untreated adults with CLL. In addition, we screened the reference lists and citation indices of included studies.

SELECTION CRITERIA

We included all prognostic models developed for CLL which predict OS, PFS, or TFS, provided they combined prognostic factors known before treatment initiation, and any studies that tested the performance of these models in individuals other than the ones included in model development (i.e. 'external model validation studies'). We included studies of adults with confirmed B-cell CLL who had not received treatment prior to the start of the study. We did not restrict the search based on study design.

DATA COLLECTION AND ANALYSIS

We developed a data extraction form to collect information based on the Checklist for Critical Appraisal and Data Extraction for Systematic Reviews of Prediction Modelling Studies (CHARMS). Independent pairs of review authors screened references, extracted data and assessed risk of bias according to the Prediction model Risk Of Bias ASsessment Tool (PROBAST). For models that were externally validated at least three times, we aimed to perform a quantitative meta-analysis of their predictive performance, notably their calibration (proportion of people predicted to experience the outcome who do so) and discrimination (ability to differentiate between people with and without the event) using a random-effects model. When a model categorised individuals into risk categories, we pooled outcome frequencies per risk group (low, intermediate, high and very high). We did not apply GRADE as guidance is not yet available for reviews of prognostic models.

MAIN RESULTS

From 52 eligible studies, we identified 12 externally validated models: six were developed for OS, one for PFS and five for TFS. In general, reporting of the studies was poor, especially predictive performance measures for calibration and discrimination; but also basic information, such as eligibility criteria and the recruitment period of participants was often missing. We rated almost all studies at high or unclear risk of bias according to PROBAST. Overall, the applicability of the models and their validation studies was low or unclear; the most common reasons were inappropriate handling of missing data and serious reporting deficiencies concerning eligibility criteria, recruitment period, observation time and prediction performance measures. We report the results for three models predicting OS, which had available data from more than three external validation studies: CLL International Prognostic Index (CLL-IPI) This score includes five prognostic factors: age, clinical stage, IgHV mutational status, B2-microglobulin and TP53 status. Calibration: for the low-, intermediate- and high-risk groups, the pooled five-year survival per risk group from validation studies corresponded to the frequencies observed in the model development study. In the very high-risk group, predicted survival from CLL-IPI was lower than observed from external validation studies. Discrimination: the pooled c-statistic of seven external validation studies (3307 participants, 917 events) was 0.72 (95% confidence interval (CI) 0.67 to 0.77). The 95% prediction interval (PI) of this model for the c-statistic, which describes the expected interval for the model's discriminative ability in a new external validation study, ranged from 0.59 to 0.83. Barcelona-Brno score Aimed at simplifying the CLL-IPI, this score includes three prognostic factors: IgHV mutational status, del(17p) and del(11q). Calibration: for the low- and intermediate-risk group, the pooled survival per risk group corresponded to the frequencies observed in the model development study, although the score seems to overestimate survival for the high-risk group. Discrimination: the pooled c-statistic of four external validation studies (1755 participants, 416 events) was 0.64 (95% CI 0.60 to 0.67); 95% PI 0.59 to 0.68. MDACC 2007 index score The authors presented two versions of this model including six prognostic factors to predict OS: age, B2-microglobulin, absolute lymphocyte count, gender, clinical stage and number of nodal groups. Only one validation study was available for the more comprehensive version of the model, a formula with a nomogram, while seven studies (5127 participants, 994 events) validated the simplified version of the model, the index score. Calibration: for the low- and intermediate-risk groups, the pooled survival per risk group corresponded to the frequencies observed in the model development study, although the score seems to overestimate survival for the high-risk group. Discrimination: the pooled c-statistic of the seven external validation studies for the index score was 0.65 (95% CI 0.60 to 0.70); 95% PI 0.51 to 0.77.

AUTHORS' CONCLUSIONS

Despite the large number of published studies of prognostic models for OS, PFS or TFS for newly-diagnosed, untreated adults with CLL, only a minority of these (N = 12) have been externally validated for their respective primary outcome. Three models have undergone sufficient external validation to enable meta-analysis of the model's ability to predict survival outcomes. Lack of reporting prevented us from summarising calibration as recommended. Of the three models, the CLL-IPI shows the best discrimination, despite overestimation. However, performance of the models may change for individuals with CLL who receive improved treatment options, as the models included in this review were tested mostly on retrospective cohorts receiving a traditional treatment regimen. In conclusion, this review shows a clear need to improve the conducting and reporting of both prognostic model development and external validation studies. For prognostic models to be used as tools in clinical practice, the development of the models (and their subsequent validation studies) should adapt to include the latest therapy options to accurately predict performance. Adaptations should be timely.

5-year survival rates based on the type of leukemia in Iran, a Meta-analysis

Background:

According to epidemiological studies, leukemia is among the five most common cancers in Iran. Keeping efforts to estimate survival is critical to monitoring and improving patients’ quality of life with leukemia. The purpose of this study was to evaluate the 5-year survival rate of leukemia patients in Iran using meta-analysis method.

Methods:

This meta-analysis was carried out according to studies that adhere to inclusion and exclusion criteria during enrolment. The valid Iranian databases included: Medex, Magiran, SID, and Medlib, along with international data bases, namely, Scopus, Pubmed, and ISI were searched to find relevant articles. After determining the heterogeneity between studies, the random effects models were used to estimate pooled survival in leukemia patients.

Results:

In total, 18 studies involving 2517 participants were included in this meta-analysis. The pooled 5-year survival rate was 0.56 % (95% CI, 0.54 to 0.58). According to types AML and ALL, the 5-year survival rates in Iran were 35.0 % (95% CI: 32.0-38.0) and 57.0 % (95% CI: 54.0-60.0), respectively.

Conclusion:

Based on our findings, slightly less than 50% of leukemia deaths happened in the first 5 years after diagnosis, which is lower than the global average.

Clinical Aspects, Immunophenotypic Analysis and Survival Rate of Chronic Lymphocytic Leukaemia Patients in Erbil City, Iraq

OBJECTIVES

Chronic lymphocytic leukaemia (CLL) is characterised by an accumulation of clonal B cells in the blood, bone marrow and lymphatic tissue. This study aimed to evaluate the clinical and immunophenotypic characteristics and survival rate of CLL patients.

METHODS

This retrospective study was conducted at the Nanakaly Hospital for Blood Diseases & Oncology in Erbil, Iraq, between January 2011 and December 2017. A total of 105 CLL patients were assessed to determine clinical presentation and staging, immunophenotype and survival rate.

RESULTS

The median age of the patients was 65 years and 63.8% were male. The main clinical presentations were splenomegaly (64.8%), pallor (61.9%) and lymphadenopathy (60%). More than half of the patients presented at an advanced clinical stage according to the Rai and Binet staging systems (59.1% and 55.2%, respectively). All CLL cases expressed both cluster of differentiation (CD)19 and CD5, 67.6% had monoclonal kappa light chains and 21% expressed CD38. The five-year overall survival (OS) rate was 61.3%. The mean duration of five-year survival was 41.3 months (95% confidence interval: 36.4-46.3 months). There were no correlations between survival and sociodemographic, clinical or laboratory characteristics.

CONCLUSION

In comparison to the existing Western literature, Iraqi CLL patients more frequently presented with hepatosplenomegaly and at a more advanced clinical stage. In addition, the five-year OS rate was much lower.

Smudge cell percentage as a surrogate marker for ZAP-70 expression in patients with chronic lymphocytic leukemia

BACKGROUND

This study aimed to evaluate the prognostic value of smudge cell percentage as a surrogate marker for zeta-chain-associated protein kinase 70 (ZAP-70) expression in chronic lymphocytic leukemia (CLL) patients.

METHODS

Sixty three newly diagnosed CLL patients were investigated at the Hematology Department of the Medical Research Institute of Alexandria University with complete blood count, lactate dehydrogenase, β2 microglobulin levels, ZAP-70 expression, and estimation of the percentage of smudge cells.

RESULTS

The percentage of smudge cells ranged from 2 to 58% with a mean of 24.03±13.98%. Higher percentages of smudge cells (>30%) were statistically significantly associated with markers of better prognosis (negative ZAP-70, early-stage disease according to the Binet and Rai staging systems, as well as low and intermediate risk CLL prognostic index). The percentage of smudge cells showed significantly negative correlation with the ZAP-70 expression and higher area under the curve for prediction of ZAP-70 positivity with better survival for 36 months in patients with >30% smudge cells.

CONCLUSION

The percentage of smudge cells at presentation of newly diagnosed CLL patients could be used as a surrogate marker for ZAP-70 expression and an additional prognostic marker for disease progression.

Clinical Significance of Smudge Cells in Peripheral Blood Smears in Hematological Malignancies and Other Diseases

BACKGROUND

It is reported that the percentage of smudge cells in the blood smear could be a prognostic indicator in chronic lymphocytic leukemia. However, the clinical significance of smudge cells in other hematological malignancies, solid tumors or non-malignant diseases is less clear. Hence, this study was conducted to survey the clinical significance of smudge cells in hematological cancers and other disorders.

MATERIALS AND METHODS

From January to November, 2015, the clinical data of patients who received blood examination with differential counts for clinical purpose and were found to have smudge cells in the peripheral blood film in Far Eastern Memorial Hospital were selected. The percentage of smudge cells and patient outcomes were evaluated for further univariate and survival analyses.

RESULTS

A total of 102 patients with smudge cells in their blood smears were included. Smudge cells were frequently presented in out-of-hospital cardiac arrest (OHCA; n=30), infections (n=23), hematological cancers (n=23) and solid cancers (n=10). There was no relationship between the percentage of smudge cells and the patient mortality in all diseases (OR: 1.08, 95% CI: 0.47-2.48, P=1.000) as well as the OHCA group (OR: 1.91, 95% CI: 0.38-9.60, P=0.694). It was observed that in patients with all cancers with the percentage of smudge cells less than 50% had a lower mortality rate in comparison with those who had the percentage of smudge cells of 50% or more (OR: 22.29, 95% CI: 2.38-208.80, <0.001). Additionally, it was seemingly that patients with smudge cells of 50% or more had a lower survival rate than those with smudge cells less than 50% in all cancers with follow-up at 2-month intervals, but without statistical significance (P=0.064).

CONCLUSIONS

Our survey indicated that in all cancers, those who had higher percentage of smudge cells were prone to have poor outcomes when compared with the subjects with lower percentage of smudge cells. This finding was quite different from the results of previous studies in which the race-ethnicity of most study populations was non-Asian; hence, further investigations are required. Besides, there was no apparent association of the percentage of smudge cells with patient outcomes in all diseases, including OHCA.

Radiation-resistant B-1 cells: A possible initiating cells of neoplastic transformation

The role of B-1 cells in the hyperproliferative hematologic disease has been described. Several reports bring evidences that B-1 cells are the main cell population in the chronic lymphatic leukemia. It is also described that these cells have an important involvement in the lupus erythematous systemic. The murine model used to investigate both disease models is NZB/NZW. Data from literature point that mutation in micro-RNA 15a and 16 are the responsible for the B-1 hyperplasia in these mice. Interestingly, it was demonstrated that NZB/NZW B-1 cells are radioresistant, contrariwise to observe in other mouse lineage derived B-1 cells and B-2 cells. However, some reports bring evidences that a small percentage of B-1 cells in healthy mice are also able to survive to irradiation. Herein, we aim to investigate the malignant potential of ionizing-radiation resistant B-1 cells in vitro. Our main goal is to establish a model that mimics the neoplastic transformation originate to a damage exposure of DNA, and not only related to intrinsic mutations. Data shown here demonstrated that radiation-resistant B-1 cells were able to survive long periods in culture. Further, these cells show proliferation index increase in relation to non-irradiated B-1 cells. In addition, radiation resistant B-1 cells showed hyperploid, morphologic alterations, increased induction of apoptosis after anti-IgM stimulation. Based on these results, we could suggest that radiation resistant B-1 cells showed some modifications in that could be related to induction of malignant potential.

Survival and Clinical Aspects for Patients with Chronic Lymphocytic Leukemia in Kermanshah, Iran

Chronic lymphocytic leukemia (CLL)is the most common leukemia in adults in Western countries but is relatively rare in Asia. Immune hemolytic anemia, Evan's syndrome, lymphadenopathy, organomegaly and B symptoms are the main complaints of patients in CLL. The present retrospective analysis evaluated a group of 109 patients with CLL over a 9-year period, studying correlations between sex, age and overall survival. The patients were hospitalized in the Clinic of Hematology and Oncology, Kermanshah, Iran, between 2006 and 2014. Data analysis for sex and age was performed using IBM SPSS19 and overall survival was plotted by Kaplan- Meier plot, Log-rank test in Graph Pad prism 5 Software for five-year periods. The mean age of diagnosis for CLL patients was 60.73 years, 59.6% male. Survival rate patients was 64% and mean overall survival was 38.5 months. In the Rai system, fourteen patients (12.8%) had stage III and twenty eight patients (25.7%) had stage IV. Most frequent clinical features in patients with CLL were lymphadenopathy (38.7%) and organomegaly (34%), respectively. There is not relationship between sex and age in patients but overall survival rate in females was higher than in males. In Asian countries, CLL is more in male and in age above 60 years. Complaints about lymphadenopathy and virus infection are prevalent.

Reverse Pseudohyperkalemia: An Important Clinical Entity in Chronic Lymphocytic Leukemia

Hyperkalemia is a potentially lethal electrolyte derangement commonly seen in patients with hematologic neoplasms with or without renal failure. Pseudohyperkalemia and reverse pseudohyperkalemia also can be seen in this patient population and early recognition and diagnosis of these conditions are vital. Here, we report a case of reverse pseudohyperkalemia in a patient with chronic lymphocytic leukemia (CLL) and provide recommendations regarding diagnostic and therapeutic strategies for management of such patients. Further, we discuss the pathogenesis of this condition and its potential role as a surrogate of favorable prognostic features in patients with CLL.