Current approach to diagnosis and management of chronic lymphocytic leukemia

An overview of prognostic markers in patients with CLL

Chronic lymphocytic leukemia (CLL) is a low-grade B-cell lymphoproliferative disorder. It is the most prevalent type of leukemia in the western countries, with a median age at diagnosis of 70 years. In 2023, it is estimated that there will be 18,740 new cases of CLL, and an estimated 4,490 people will die of this disease. It represents 1.0% of all new cancer cases in the U.S. The rate of new cases was 4.6 per 100,000 men and women per year based on 2016-2020 cases, age-adjusted. Death rates from CLL are higher among older adults, or those 75 and older. The death rate was 1.1 per 100,000 men and women per year based on 2016-2020 deaths, age-adjusted. A common question that patients with CLL ask during their first clinic visit is: "How long will it be before I would need treatment?" Although this might seem like a simple question, the answer is not straight forward. CLL is a heterogenous disease, with a variable clinical course. Some patients may present with an aggressive disease requiring early initiation of treatment, while others have an indolent course and some, having so called smoldering CLL, may never need treatment. The variability in disease course can make predicting disease prognosis a complicated process. This brings forth the importance of establishing prognostic models that can predict disease course, time to treatment, and survival outcomes in such a heterogenous disease. The Rai and Binet staging systems were developed in the late 1970s to early 1980s. They separated patients into different stages based on clinical characteristics and laboratory findings. These simple staging systems are still in use; however, several prognostic markers need to be added for an individualized assessment and, with the recent development of genomic techniques leading to better understanding of CLL at the molecular level, newer prognostic markers have emerged.

Cutaneous Squamous Cell Carcinoma in Immunocompromised Patients—A Comparison between Different Immunomodulating Conditions

Background: Immunosuppression is strongly associated with an increased risk of developing cutaneous squamous cell carcinoma (cSCC). Studies on solid organ transplant recipients (SOTR) and chronic lymphocytic leukemia (CLL) patients have already demonstrated higher rates of aggressive cSCC tumors in these populations compared to immunocompetent controls. Studies on other immunosuppressed patient groups are scarce. This study was aimed at assessing the effects of different immunomodulating conditions on patients diagnosed with cSCC. We sought to compare the clinical features, treatments, and survival rates among the different study groups, as well as outcomes to those of immunocompetent controls with cSCC. Methods: A retrospective analysis of 465 cSCC patients, both immunosuppressed (IS) and immunocompetent controls. Etiologies for immunosuppression included SOTR, CLL, chronic kidney disease (CKD), psoriasis, rheumatoid arthritis (RA) and systemic lupus erythematous (SLE). Results: Compared to the control group, IS patients demonstrated several significant differences. These include higher rates of positive resection margins, higher recurrence rates, and multiple SCC tumors. Patients in the IS group, who were also given immunomodulating agents, demonstrated even lower survival rates. Cox regression analysis demonstrated statistically significant decreased overall survival (OS) rates for IS patients compared to the controls (OR = 1.9, p = 0.031). SOTR patients tend to have multiple cSCC tumors (35%), with the highest number of primary tumors compared to controls (2.54 tumors per patient on average, p < 0.001), but also compared to all other IS groups. The average SCC lesion size in the SOTR group was the smallest, measuring at 13.5 mm, compared to the control group and all other IS groups. Decreased survival rates were seen on Cox regression analysis compared to controls (HR = 2.4, p = 0.001), but also to all other IS groups. CLL patients also had the highest rates of positive margins compared to controls (36% vs. 9%, p < 0.01) and to all other IS groups. They were also most likely to get adjuvant or definitive oncological treatments, either radiotherapy or chemotherapy, compared to controls (36% vs. 15%, p = 0.02) and to other IS groups. Patients in the CKD group demonstrated the highest rates for multiple cSCC (OR = 4.7, p = 0.001) and the worst rates of survival on Cox regression analysis (HR = 3.2, p = 0.001). Both rheumatoid arthritis and psoriasis patients demonstrated the shortest disease-free survival rates (2.9y ± 1.1, 2.3y ± 0.7, respectively), compared to controls (4.1y ± 2.8) and to all other IS groups. Conclusions: Among cSCC patients, immunosuppression due to SOTR, CLL, CKD, RA, and psoriasis is associated with worse outcomes compared to controls and other IS groups. These patients should be regarded as high-risk for developing aggressive cSCC tumors. This study is the first to assess and compare cSCC outcomes among multiple IS patient groups.

Role of cytogenetic abnormalities detected by fluorescence in situ hybridization as a prognostic marker: Pathogenesis & clinical course in patients with B-chronic lymphocytic leukaemia

Background & objectives:

B-cell chronic lymphocytic leukaemia (B-CLL) is one of the most common forms of adult leukaemia, with a highly variable clinical course. Specific chromosomal and genetic aberrations are used clinically to predict prognosis, independent from conventional clinical markers. Molecular cytogenetic methods such as fluorescence in situ hybridization (FISH) detect aberrations in up to 80 per cent B-CLL patients. This study was conducted to score the frequencies of recurrent aberrations, i.e., del(13q14), trisomy 12, del(11q22), del(17p13), del(6q21) and IgH (immunoglobulin heavy chain) translocations and to understand their role in prognostication and risk stratification.

Methods:

FISH studies were performed on bone marrow aspirate or peripheral blood of 280 patients using commercially available disease-specific probe set. The data were correlated with clinical and haematological parameters such as low haemoglobin, splenomegaly and lymphadenopathy.

Results:

Chromosomal aberrations were detected in 79 per cent of patients, with del(13q14) (57%) as the most common cytogenetic aberration, followed by trisomy 12 (27%), del(11q22) (22%), t(14q32) (19%), del(17p13) (18%) and del(6q21) (9%). Single or in coexistence with other aberration del(13q14) had a favourable outcome in comparison to del(11q22), t(14q32), del(17p13) and del(6q21) which were associated with advanced stages of the disease. Trisomy 12 had a variable clinical course.

Interpretation & conclusions:

FISH was found to be a sensitive and efficient technique in detecting the prevalence of recurrent cytogenetic abnormalities. Each of these aberrations is an important independent predictor of disease progression and survival which aids in designing risk-adapted treatment strategies for better disease management.

Clinical considerations about the coexistence of melanoma and chronic lymphocytic leukemia in the era of targeted therapies, triggered by rare clinical scenarios. A case series and review of the literature

The epidemiologic correlation of melanoma and chronic lymphocytic leukemia (CLL) has been the subject of several population studies. In the present article, through the presentation of five illustrative cases of patients with melanoma and CLL, several aspects of this complex relationship are highlighted, with a focus on the increased incidence of melanoma in patients with CLL, its speculated etiology, and the impact of CLL stage and disease duration on the incidence and prognosis of melanoma. Furthermore, the rare entity of the synchronous diagnosis of melanoma and CLL in biopsied lymph nodes is discussed, along with its implications on the diagnostic and therapeutic procedures. In addition, the available data on the treatment choices in patients with melanoma and CLL are presented and the efficacy and safety of fludarabine, anti-CD20 monoclonal antibodies, new targeted therapies for CLL, and checkpoint inhibitors are further discussed. Finally, since no formal guidelines are available for the management of this group of patients, guidelines are proposed for skin-cancer screening in patients with CLL, for the correct interpretation of BRAF mutation analysis in lymph-node specimens with ‘collision of tumors,’ and for the optimal use of imaging studies in the diagnosis of metastatic disease in patients with CLL and melanoma, while a treatment approach for such patients is also suggested. The information and proposed guidelines provided in the present article comprise a useful guide for physicians managing such patients, focusing on diagnostic challenges and therapeutic dilemmas posed by the coexistence of the two disease entities.

On-chip sample preparation for complete blood count from raw blood

This paper describes a monolithic microfluidic device capable of on-chip sample preparation for both RBC and WBC measurements from whole blood. For the first time, on-chip sample processing (e.g. dilution, lysis, and filtration) and downstream single cell measurement were fully integrated to enable sample preparation and single cell analysis from whole blood on a single device. The device consists of two parallel sub-systems that perform sample processing and electrical measurements for measuring RBC and WBC parameters. The system provides a modular environment capable of handling solutions of various viscosities by adjusting the length of channels and precisely controlling mixing ratios, and features a new 'offset' filter configuration for increased duration of device operation. RBC concentration, mean corpuscular volume (MCV), cell distribution width, WBC concentration and differential are determined by electrical impedance measurement. Experimental characterization of over 100,000 cells from 10 patient blood samples validated the system's capability for performing on-chip raw blood processing and measurement.

Minimal residual disease detection with tumor-specific CD160 correlates with event-free survival in chronic lymphocytic leukemia

In chronic lymphocytic leukemia (CLL), the detection of minimal residual disease (MRD) correlates with outcome in the trial setting. However, MRD assessment does not guide routine clinical management and its assessment remains complex. We incorporated detection of the B cell, tumor-specific antigen CD160 to develop a single-tube, flow cytometry assay (CD160FCA) for CLL MRD to a threshold of 10⁻⁴ to 10⁻⁵. One hundred and eighty-seven patients treated for CLL were enrolled. Utilizing the CD160FCA methodology, there was a high level of comparison between blood and bone marrow (R=0.87, P<0.001). In a validation cohort, CD160FCA and the international standardised approach of the European Research Initiative on CLL group demonstrated high concordance (R=0.91, P<0.01). Patients in complete remission (CR) and CD160FCA negative had longer event-free survival (EFS) (63 vs 16 months, P<0.01) and prolonged time to next treatment (60 vs 15 months, P<0.001) vs MRD positive patients; with a median time to MRD positivity of 36 months. In multivariate analysis, CD160FCA MRD detection was independently predictive of EFS in patients in CR and even predicted EFS in the good-risk cytogenetic subgroup. CD160FCA offers a simple assay for MRD detection in CLL and gives prognostic information across different CLL risk groups.

Skin cancer surveillance and malignancies of the skin in a community-dwelling cohort of patients with newly diagnosed chronic lymphocytic leukemia

PURPOSE

Assess compliance with skin cancer screening guidelines in a community-dwelling cohort of patients with newly diagnosed chronic lymphocytic leukemia (CLL) and evaluate the clinical utility of such screening.

METHODS

We identified patients diagnosed at Mayo Clinic with CLL between January 1, 2004, and June 1, 2012, who resided within 30 miles of Mayo Clinic. We evaluated adherence to skin cancer screening and identified the prevalence of skin malignancies during follow-up. Medical records were reviewed to document skin cancer screening and diagnosis of a skin malignancy.

RESULTS

Collectively, 113 individuals who met criteria were diagnosed with CLL during the study interval. Forty-one patients (36%) had a whole body skin examination by either a dermatologist or primary care provider documented within 6 months of diagnosis; of these; nine (8% of overall cohort; 22% of examined patients) had a skin malignancy identified. Fifteen additional skin malignancies were diagnosed during follow-up. There were a total of 24 skin malignancies (21% of cohort) diagnosed, including basal cell carcinoma (n = 10), squamous cell carcinoma (n = 11), sebaceous carcinomas (n = 2), and melanoma (n = 1).

CONCLUSION

We documented a low compliance with guidelines to screen for skin malignancy in a community-dwelling cohort of patients with newly diagnosed CLL. Standardized and systems-based approaches are likely to increase compliance with skin cancer screening guidelines in patients with CLL.

Inhibition of nuclear factor kappa B activation in early-stage chronic lymphocytic leukemia by omega-3 fatty acids

Targeting the nuclear factor kappa B (NFκB) pathway is proposed as therapy for chronic lymphocytic leukemia (CLL). We hypothesized that an omega-3 fatty acids (n-3) supplement would suppress NFκB activation in lymphocytes of Rai Stage 0-1 CLL patients. The initial dose of 2.4 g n-3/day was gradually increased to 7.2 g n-3/day. After n-3 consumption: 1) plasma n-3 increased; 2) NFκB activation was suppressed in lymphocytes; 3) in vitro sensitivity of lymphocytes to doxorubicin was increased; and 4) expression of 32 genes in lymphocytes was significantly decreased.

Ofatumumab: a novel anti-CD20 monoclonal antibody for treatment of refractory chronic lymphocytic leukemia

OBJECTIVE

To present the current clinical evidence on ofatumumab for use in refractory chronic lymphocytic leukemia (CLL).

DATA SOURCES

A literature search was performed using MEDLINE and PubMed (both 1966-May 2011), as well as the American Society of Hematology abstracts (2000-May 2011), using the primary search terms ofatumumab and HuMax-CD20.

STUDY SELECTION AND DATA EXTRACTION

Clinical studies and abstracts available in the English language, describing the pharmacology, pharmacokinetics, clinical activity, and safety of ofatumumab in CLL were included in this review.

DATA SYNTHESIS

Ofatumumab is a human immunoglobulin monoclonal antibody that binds to B-lymphocytes expressing CD-20 cell surface antigens. Ofatumumab was granted accelerated approval by the Food and Drug Administration in October 2009 for the treatment of CLL refractory to fludarabine and alemtuzumab. A Phase 1/2 trial has established the safety and tolerability of single-agent ofatumumab at an initial dose of 300 mg intravenously on week 1, followed by 2000 mg once weekly for 7 doses (weeks 2-8), followed by 2000 mg once every 4 weeks for 4 doses (weeks 9-12), for a total of 12 doses. The final analysis of a pivotal international multicenter trial has shown promising activity in patients with CLL refractory to fludarabine and alemtuzumab, demonstrating overall response rates of 44-51%, with prolonged progression-free and overall survival. Ofatumumab activity has also been shown in a variety of other malignant and nonmalignant conditions, including non-Hodgkin lymphoma, rheumatoid arthritis, and multiple sclerosis. The most common adverse effect is grade 1 and 2 infusion reactions. Other adverse effects include infection, neutropenia, anemia, rash, fever, and diarrhea.

CONCLUSIONS

Clinical evidence suggests that ofatumumab is an effective agent in patients with CLL refractory to fludarabine and alemtuzumab. Data are awaited comparing ofatumumab to other salvage regimens. Until results of head-to-head trials are conducted comparing ofatumumab to existing regimens, it cannot be said whether ofatumumab is more efficacious or tolerable than currently available therapies.

Cytogenetic methods in chronic lymphocytic leukemia

In chronic lymphocytic leukemia of the B-lineage (B-CLL), cytogenetic alterations are highly relevant for prognosis and therapeutic decisions. With conventional techniques, chromosome banding analysis in CLL has been hampered by the low quality of metaphases and low rates of cytogenetic alterations due to a low in vitro proliferation rate of CLL cells. Thus, interphase fluorescence in situ hybridization (FISH) has become the standard technique for cytogenetic analysis in CLL. However, interphase FISH is not able to provide an overview on the whole karyotype. In order to improve chromosome banding analysis in CLL, specific stimulation techniques have been developed. These either use CD40 ligand or oligonucleotides (e.g., CpG) and IL-2 in combination. With the respective techniques, metaphase cultivation is successful in >90% of CLL cases and aberrant karyotypes can be detected in nearly 90% of CLL cases. This has allowed the detection of new clinically relevant subgroups (e.g., complex aberrant karyotype cases) and a more differentiated picture of distinct cytogenetic subtypes, e.g., cases with a 13q deletion. Efforts should continue to define the value of chromosomal banding in CLL focusing as well on the interaction with already established techniques such as interphase FISH or immunophenotyping.

Timeliness and quality of diagnostic care for medicare recipients with chronic lymphocytic leukemia

BACKGROUND

Little is known about the patterns of care relating to the diagnosis of chronic lymphocytic leukemia (CLL), including the use of modern diagnostic techniques such as flow cytometry.

METHODS

The authors used the SEER-Medicare database to identify subjects diagnosed with CLL from 1992 to 2002 and defined diagnostic delay as present when the number of days between the first claim for a CLL-associated sign or symptom and SEER diagnosis date met or exceeded the median for the sample. The authors then used logistic regression to estimate the likelihood of delay and Cox regression to examine survival.

RESULTS

For the 5086 patients analyzed, the median time between sign or symptom and CLL diagnosis was 63 days (interquartile range [IQR] = 0-251). Predictors of delay included age ≥75 (OR 1.45 [1.27-1.65]), female gender (OR 1.22 [1.07-1.39]), urban residence (OR 1.46 [1.19 to 1.79]), ≥1 comorbidities (OR 2.83 [2.45-3.28]) and care in a teaching hospital (OR 1.20 [1.05-1.38]). Delayed diagnosis was not associated with survival (HR 1.11 [0.99-1.25]), but receipt of flow cytometry within thirty days before or after diagnosis was (HR 0.84 [0.76-0.91]).

CONCLUSIONS

Sociodemographic characteristics affect diagnostic delay for CLL, although delay does not seem to impact mortality. In contrast, receipt of flow cytometry near the time of diagnosis is associated with improved survival.

Chronic lymphocytic leukemia associated with myelodysplastic syndrome with ring sideroblasts

Diagnosis of myelodysplastic syndrome/acute myeloid leukemia (MDS/AML) and chronic lymphocytic leukemia (CLL) in the same patient is extremely rare. We describe a 69-year-old CLL patient who developed MDS with ring sideroblasts 1 year after diagnosis of CLL and without any previous treatment. Diagnosis was based on flow cytometry, bone marrow aspirate morphology, and iron stain. Our findings indicate that the 2 disorders belong to 2 different hematopoietic clones in this patient. In cases of worsening anemia in CLL patients, it is recommended that an iron stain be performed on bone marrow aspirates to exclude a coexistent malignancy such as refractory anemia with ring sideroblasts.

Fine-scale mapping of the 6p25.3 chronic lymphocytic leukaemia susceptibility locus

A recent genome-wide association study of chronic lymphocytic leukaemia (CLL) has identified a susceptibility locus on 6p25.3 associated with a modest but highly significant increase in CLL risk. Using a set of single nucleotide polymorphism (SNP) markers, we generated a fine-scale map and narrowed the association signal to a 18 kb DNA segment within the 3'-untranslated region (UTR) of the IRF4 (interferon regulatory factor 4) gene. Resequencing this segment in European subjects identified 55 common polymorphisms, including 13 highly correlated candidate causal variants. In a large case-control study, it was shown that all but four variants could be excluded with 95% confidence. These four SNPs map to a 3 kb region of the 3'-UTR of IRF4, consistent with the causal basis of the association being mediated through differential IRF4 expression.

Fludarabine phosphate for the first-line treatment of chronic lymphocytic leukaemia

This paper presents a summary of the evidence review group (ERG) report into the clinical and cost-effectiveness of fludarabine phosphate or fludarabine plus cyclophosphamide for the first-line treatment of chronic lymphocytic leukaemia, based upon the evidence submission from Schering Health Care (SHC) to the National Institute for Health and Clinical Excellence (NICE) as part of the single technology appraisal (STA) process. The submission was of good quality with no major errors or omissions in the clinical evidence. Two published studies and seven abstracts were included in the company submission, which showed improvements in overall response and progression-free survival (PFS) and a higher complete response rate in the fludarabinecontaining arms; however, until the complete data are made available for evaluation these results must be interpreted with caution. The manufacturer’s decision-analytic Markov model to estimate the cost-effectiveness of treatment with fludarabine monotherapy, fludarabine plus cyclophosphamide and chlorambucil was considered to be the most relevant source for informing this STA; it was appropriate for the decision problem and the data sources used to inform the model were appropriate from a UK NHS perspective. The incremental cost-effectiveness ratio of fludarabine plus cyclophosphamide compared with chlorambucil from the revised model presented in the manufacturer’s addendum was £3244 per additional quality-adjusted life-year. The results were robust to a range of subgroup and sensitivity analyses. Additional sensitivity and survival analyses were carried by the ERG to investigate possible bias in the results. This brought into question the validity of the assumptions underpinning the extrapolation of data over a lifetime time horizon and showed that the ICER estimates submitted by the manufacturer were not calculated correctly and uncertainty surrounding the decision problems was not expressed fully. Based on these analyses the ERG suggests that further evidence is needed to enable an accurate assessment to be made of the clinical and cost-effectiveness of fludarabine as first-line treatment for chronic lymphocytic leukaemia. The guidance issued by NICE in December 2006 as a result of the STA states that fludarabine monotherapy, within its licensed indication, is not recommended for the first-line treatment of chronic lymphocytic leukaemia; no recommendations have been made with respect to fludarabine plus cyclophosphamide combination therapy because the current marketing authorisation does not specifically provide a recommendation that fludarabine should be used concurrently with other drugs for the treatment of chronic lymphocytic leukaemia.

Phase II study of single-agent bortezomib for the treatment of patients with fludarabine-refractory B-cell chronic lymphocytic leukemia

Therapeutic options are limited and the prognosis is poor for patients with fludarabine-refractory B-cell chronic lymphocytic leukemia (CLL). Bortezomib induces apoptosis in vitro in CLL cells, both alone and in combination, including in cells resistant to fludarabine or other agents. The aim of the current randomized, open-label, Phase II study was to investigate the clinical activity of bortezomib in patients with fludarabine-refractory B-cell CLL. Twenty-two patients with histologically confirmed B-cell CLL were treated with bortezomib at doses of 1.0 mg/m2, 1.3 mg/m2, or 1.5 mg/m2 on Days 1, 4, 8, and 11 of a 21-day treatment cycle for a maximum of 9 cycles. None of 19 patients evaluable for response achieved complete remission or partial response; however, signs of biologic activity based on disease site responses (e.g., reduction in lymphocytosis, splenomegaly, and lymphadenopathy) were observed. In the 1.5 mg/m2 dose group, a higher proportion of patients had stable disease, and a lower proportion had progressive disease compared with the 2 lower-dose groups. Eleven patients, all in the 2 higher dose groups, experienced Grade 3/4 adverse events (AEs) (according to National Cancer Institute Common Toxicity Criteria [version 2.0]); 2 patients experienced Grade 4 neutropenia. Grade 3 hematologic AEs included anemia, neutropenia, thrombocytopenia, and hemolytic anemia; Grade 3 nervous system AEs included aphasia; peripheral neuropathy, not otherwise specified; and peripheral sensory neuropathy. Although no objective responses were achieved in patients with fludarabine-refractory B-cell CLL, single-agent bortezomib demonstrated biologic activity. In view of the evidence for its activity, further exploration of bortezomib in combination with other agents is warranted.

A new automated flow cytometry data analysis approach for the diagnostic screening of neoplastic B-cell disorders in peripheral blood samples with absolute lymphocytosis

Currently, multiparameter flow cytometry immunophenotyping is the selected method for the differential diagnostic screening between reactive lymphocytosis and neoplastic B-cell chronic lymphoproliferative disorders (B-CLPD). Despite this, current multiparameter flow cytometry data analysis approaches still remain subjective due to the need of experienced personnel for both data analysis and interpretation of the results. In this study, we describe and validate a new automated method based on vector quantization algorithms to analyze multiparameter flow cytometry immunophenotyping data in a series of 307 peripheral blood (PB) samples. Our results show that the automated method of analysis proposed compares well with currently used manual approach and significantly improves semiautomated approaches and, that by using it, a highly efficient discrimination with 100% specificity and 100% sensitivity can be made between normal/reactive PB samples and cases with B-CLPD based on the total B-cell number and/or the sIgkappa+/sIglambda+ B-cell ratio. In addition, the method proved to be able to detect the presence of pathologic neoplastic B-cells even when these are present at low frequencies (<5% of all lymphocytes in the sample) and in poor-quality samples enriched in 'noise' events.

A robust ratio metric method for analysis of Zap-70 expression in chronic lymphocytic leukemia (CLL)

Since Zap-70 expression in chronic lymphocytic leukemia (CLL) cells correlates with a lack of somatic mutation of the immunoglobulin variable heavy chain (IgVH) genes, it has been proposed as a surrogate marker for disease prognosis. However, published studies of Zap-70 expression have used different commercial antibodies and analytic strategies. This study was undertaken to determine if any strategy was broadly applicable in a clinical flow cytometry laboratory. Expression of Zap-70 was determined in 37 CLL patients using four different commercial antibodies. T, NK, and CLL cells were identified by immunophenotyping along with Zap-70 expression. Data was analyzed in terms of both percent of CLL cells expressing Zap-70 and the ratio of Zap-70 expression in CLL cells compared to that in T + NK cells. Three Zap-70 antibodies showed wide ranges of Zap-70 expression as a percentage of tumor cells, while a fourth gave consistently elevated results. Comparing the percent Zap-70 expression with any two antibodies gave poor correlations (r(2) = 0.45-0.63). Our results indicated that the previous analytical strategies were not reproducible. A ratio metric is proposed, which gave better correlations (r(2) as high as 0.95) and would allow separation of CLL patients with elevated or decreased Zap-70 expression.