Lymphocyte Doubling Time As A Key Prognostic Factor To Predict Time To First Treatment In Early-Stage Chronic Lymphocytic Leukemia.

The prognostic role of lymphocyte doubling time (LDT) in chronic lymphocytic leukemia (CLL) was recognized more than three decades ago when the neoplastic clone's biology was almost unknown. LDT was defined as the time needed for the peripheral blood lymphocyte count to double the of the initial observed value. Herein, the LDT prognostic value for time to first treatment (TTFT) was explored in our prospective O-CLL cohort and validated in in two additional CLL cohorts. Specifically, newly diagnosed Binet stage A CLL patients from 40 Italian Institutions, representative of the whole country, were prospectively enrolled into the O-CLL1-GISL protocol (clinicaltrial.gov identifier: NCT00917540). Two independent cohorts of newly diagnosed CLL patients recruited respectively at the Division of Hematology in Novara, Italy, and at the Hospital Clinic in Barcelona, Spain, were utilized as validation cohorts. In the training cohort, TTFT of patients with LDT >12 months was significantly longer related to those with a shorter LDT. At Cox multivariate regression model, LDT ≤ 12 months maintained a significant independent relationship with shorter TTFT along with IGHV unmutated (IGHVunmut) status, 11q and 17p deletions, elevated ß2M, Rai stage I-II, and NOTCH1 mutations. Based on these statistics, two regression models were constructed including the same prognostic factors with or without the LDT. The model with the LTD provided a significantly better data fitting (χ2 = 8.25, P=0.0041). The risk prediction developed including LDT had better prognostic accuracy than those without LDT. Moreover, the Harrell'C index for the scores including LDT were higher than those without LDT, although the accepted 0.70 threshold exceeded in both cases. These findings were also confirmed when the same analysis was carried out according to TTFT's explained variation. When data were further analyzed based on the combination between LDT and IGHV mutational status in the training and validation cohorts, IGHVunmut and LDT>12months group showed a predominant prognostic role over IGHVmut LTD ≤ 12 months (P=0.006) in the O-CLL validation cohort. However, this predominance was of borden-line significance (P=0.06) in the Barcelona group, while the significant prognostic impact was definitely lost in the Novara group. Overall, in this study, we demonstrated that LDT could be re-utilized together with the more sophisticated prognostic factors to manage the follow-up plans for Binet stage A CLL patients.

COVID-19 and Chronic Lymphocytic Leukemia: Where We Stand Now.

ABSTRACT: Coronavirus disease 2019 (COVID-19) has markedly impacted on the management of patients with chronic lymphocytic leukemia (CLL) and their outcome in the last year. The cumulative incidence of COVID-19 in patients with CLL in 1 year was approximately 3% in the recent Italian CAMPUS CLL survey; large retrospective studies have documented a higher mortality in patients with CLL hospitalized for severe COVID-19 compared with the general population. Controversial results for CLL-directed treatment have been reported, with some studies suggesting a potential benefit for BTK inhibitors. Reducing the number of hospital visits, delaying treatment whenever possible, and using oral therapy have become the mainstay of management in these patients. Available results with severe acute respiratory syndrome coronavirus 2 vaccines indicate an immune serological response in 40% of patients only, with a detrimental effect of recent therapy with or without anti-CD20 therapy, older age, and hypogammaglobulinemia. Further studies are needed to determine the best strategies in patients with CLL regarding (i) management of concomitant COVID-19, (ii) identification of patients in whom CLL therapy can be safely postponed, (iii) CLL treatment algorithms, and (iv) optimal severe acute respiratory syndrome coronavirus 2 vaccination strategies.

Lymphocyte doubling time in chronic lymphocytic leukemia modern era: a real-life study in 848 unselected patients.

The prognostic significance of lymphocyte doubling time (LDT) in chronic lymphocytic leukemia (CLL) was identified when the biology of the disease was poorly understood and therapy was not effective. We assessed the clinical and biological significance of LDT in 848 CLL patients in a real-life setting and the context of new biomarkers and effective therapy. A short LDT (≤12 months) was enriched for adverse biomarkers. Patients with a rapid LDT did need therapy shortly after diagnosis (median 23 months vs. not reached; p < 0.001) and had a poorer overall survival (median 95 months vs. not reached p < 0.001). LDT, IGHV mutational status, Beta-2 microglobulin, and Rai clinical stage were independent predictors for time to first treatment in the whole series and in Binet stage A patients. No correlation was observed between LDT and response to chemoimmunotherapy. However, a short LDT along with age ≥65 years, high-risk FISH (del(17p), del(11q)), unmutated IGHV, increased Beta-2 microglobulin, and TP53 mutations predicted short survival. Moreover, the prognostic significance of LDT was independent of the CLL-IPI and the Barcelona/Brno prognostic model. LDT remains an important outcome marker in the modern CLL era and should be incorporated into the clinical assessment and stratification of CLL patients.

Comparison Between Venetoclax-based and Bruton Tyrosine Kinase Inhibitor-based Therapy as Upfront Treatment of Chronic Lymphocytic Leukemia (CLL): A Systematic Review and Network Meta-analysis.

BACKGROUND: Available targeted agents (TAs) for the upfront therapy of chronic lymphocytic leukemia (ie, ibrutinib, acalabrutinib, venetoclax) have rarely been compared in head-to-head clinical trials. In search of data for evidence-based treatment decisions, a systematic literature review and network meta-analysis was performed. MATERIALS AND METHODS: The screening process adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Guidelines (PRISMA). RESULTS: Only 3 trials were suitable for the base-case network analysis (ILLUMINATE, ELEVATE-TN, and CLL14). Regarding progression-free survival (PFS), fixed-effect analyses comparing ibrutinib-obinutuzumab (IO) with venetoclax-obinutuzumab (VO) (relative risk [RR], 1.52; 95% confidence interval [CI], 0.82-2.81), acalabrutinib (A) with IO (RR, 0.87; 95% CI, 0.47-1.61), and A with VO (RR, 0.57; 95% CI, 0.32-1.01) revealed that the upper limit of the 95% CI for RR did exceed the 1.0 value. This indicates a lack of significant difference in PFS for IO, VO, and A. In contrast, acalabrutinib plus obinutuzumab (AO) improved PFS in comparison with IO (RR, 0.43; 95% CI, 0.22-0.87) and VO (RR, 0.29; 95% CI, 0.15-0.56). No differences in the frequency of adverse events was observed across different TAs. Also, the analysis of PFS in relationship with high-risk genetic features (ie, TP53 aberrations, IGHV unmutated, 11q deletion) showed similar results for different TAs. However, patients with unmutated IGHV status fared better with AO than with VO in terms of PFS. CONCLUSIONS: This systematic review and network meta-analysis indicated that upfront AO prolongs PFS in comparison with IO and VO, whereas no differences are observed between IO, VO, and single-agent A. Hopefully, ongoing studies will further delineate the position of different TAs in chronic lymphocytic leukemia therapy based on effectiveness, availability, safety, cost, and treatment objectives.

How We Manage Patients With Chronic Lymphocytic Leukemia During the SARS-CoV-2 Pandemic.

Infections are a major cause of morbidity and mortality in patients with chronic lymphocytic leukemia (CLL). These can be exacerbated by anti-leukemic treatments. In addition, the typical patients with CLL already have fragilities and background risk factors that apply to the general population for severe COVID-19. On these bases, patients with CLL may experience COVID-19 morbidity and mortality. Recurrent seasonal epidemics of SARS-CoV-2 are expected, and doctors taking care of patients with CLL must be prepared for the possibility of substantial resurgences of infection and adapt their approach to CLL management accordingly. In this Guideline Article, we aim at providing clinicians with a literature-informed expert opinion on the management of patients with CLL during SARS-CoV-2 epidemic.

International prognostic score for asymptomatic early-stage chronic lymphocytic leukemia.

Most patients with chronic lymphocytic leukemia (CLL) are diagnosed with early-stage disease and managed with active surveillance. The individual course of patients with early-stage CLL is heterogeneous, and their probability of needing treatment is hardly anticipated at diagnosis. We aimed at developing an international prognostic score to predict time to first treatment (TTFT) in patients with CLL with early, asymptomatic disease (International Prognostic Score for Early-stage CLL [IPS-E]). Individual patient data from 11 international cohorts of patients with early-stage CLL (n = 4933) were analyzed to build and validate the prognostic score. Three covariates were consistently and independently correlated with TTFT: unmutated immunoglobulin heavy variable gene (IGHV), absolute lymphocyte count higher than 15 × 109/L, and presence of palpable lymph nodes. The IPS-E was the sum of the covariates (1 point each), and separated low-risk (score 0), intermediate-risk (score 1), and high-risk (score 2-3) patients showing a distinct TTFT. The score accuracy was validated in 9 cohorts staged by the Binet system and 1 cohort staged by the Rai system. The C-index was 0.74 in the training series and 0.70 in the aggregate of validation series. By meta-analysis of the training and validation cohorts, the 5-year cumulative risk for treatment start was 8.4%, 28.4%, and 61.2% among low-risk, intermediate-risk, and high-risk patients, respectively. The IPS-E is a simple and robust prognostic model that predicts the likelihood of treatment requirement in patients with early-stage CLL. The IPS-E can be useful in clinical management and in the design of early intervention clinical trials.

Predicting the outcome of patients with chronic lymphocytic leukemia: Progress and uncertainty.

Because chronic lymphocytic leukemia is a heterogeneous disease, there are considerable efforts underway to develop increasingly accurate and precise analytics with which to estimate the probability of future events such as the need for and probability of response to therapy, progression-free survival, and survival. These analytics typically are constructed from clinical and laboratory variables. These variables often are combined into scores or staging systems, some of which are prognostic (therapy-independent), whereas others are predictive (therapy-dependent). Predictive variables differ with different therapies. Because response to therapy is a necessary condition for the improvement of survival, predictive biomarkers are extremely important. However, despite some progress to identify new predictive biomarkers, del(17p)/TP53 mutation remains the only widely accepted variable used to guide therapy. New laboratory techniques and analytical tools may contribute to improvements in the precision and accuracy of outcome indicators. However, there are inherent limitations when applying cohort-based estimates to individuals within the cohort. The accuracy and precision of prediction also are limited by measurement error and chance. Ultimately, estimating outcomes requires a careful balance between clinical experience, imperfect prediction, and uncertainty.

Minimal Residual Disease and Survival Outcomes in Patients With Chronic Lymphocytic Leukemia: A Systematic Review and Meta-analysis.

BACKGROUND: Patients with chronic lymphocytic leukemia (CLL) who achieve undetectable minimal residual disease (U-MRD) (ie, < 10-4 detectable leukemic cells in peripheral blood or bone marrow) have better outcomes than those with detectable MRD. To assess the magnitude of improvement of progression-free survival (PFS) or overall survival (OS) in patients who achieved U-MRD after upfront chemotherapy (CT) or chemo-immunotherapy (CIT), we conducted a systematic review and meta-analysis. MATERIALS AND METHODS: The screening process adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Guidelines. The search strategy yielded 365 records, including 22 articles assessed for eligibility. RESULTS: Eleven studies comprising 2457 patients with CLL treated in upfront with CT or CIT were considered suitable for inclusion in the quantitative meta-analysis. Nine studies (n = 2088) provided data on the impact of MRD on PFS and 6 (n = 1234) on OS. MRD was the main endpoint in only 2 of these studies (n = 213). Tests of heterogeneity revealed significant differences among studies for PFS and OS, which highlights differences across studies. U-MRD status was associated with significantly better PFS overall (P < .001) and in patients who achieved conventional complete remission (P = .01). Regarding OS, U-MRD predicted longer OS globally (P < .001) but not in patients having achieved complete remission (P = .82). CONCLUSIONS: U-MRD status after treatment with CT or CIT in newly diagnosed CLL is associated with long-term survival. These findings provide quantitative evidence to support the integration of MRD assessment as an end point in clinical trials of CLL.

Critical molecular pathways in CLL therapy.

Chronic lymphocytic leukemia (CLL), the most frequent type of leukemia in western countries, is characterized by the progressive accumulation in blood, bone marrow and lymphoid tissues of monoclonal B lymphocytes with a characteristic immunophenotype. Despite advances in therapy and improved outcome, in most instances CLL is an incurable disorder. Signaling via the B-cell receptor (BCR), the upregulation of anti-apoptotic proteins, and the cross-talk between CLL cells and microenvironment constitute key factors in the pathogenesis of CLL. Currently, inhibitors of kinases like BTK or PI3K blocking BCR signaling, and molecules that mimic the BH3 domain to compete with BCL-2 are established tools in the treatment of CLL. As the complex biology of CLL is rapidly unfolding, the number of small molecules targeting CLL molecular pathways is increasing and it is likely that they will further improve the outcome of patients with this form of leukemia.

High-risk chronic lymphocytic leukemia in the era of pathway inhibitors: integrating molecular and cellular therapies.

High-risk chronic lymphocytic leukemia (CLL) has been defined by clinical and/or genetic resistance (TP53 abnormalities) to treatment with chemoimmunotherapy (CIT). With the availability of pathway inhibitors (PIs), such as kinase inhibitors and BCL2 antagonists, the outlook of CIT-resistant patients has dramatically improved. Here, we propose a revision of the concept of high-risk CLL, driven by TP53 abnormalities and response to treatment with PI. CLL high-risk-I, CIT-resistant is defined by clinically CIT-resistant disease with TP53 aberrations, but fully responsive to PI. This category is largely the domain of PI-based therapy, and cellular therapy (ie, allogeneic hematopoietic cell transplantation) remains an option only in selected patients with low individual procedure-related risk. In CLL high-risk-II, CIT- and PI-resistant, characterized by increasing exhaustion of pharmacological treatment possibilities, cellular therapies (including chimeric antigen receptor-engineered T cells) should be considered in patients eligible for these procedures. Moreover, molecular and cellular therapies are not mutually exclusive and could be used synergistically to exploit their full potential.