Elisa Bernocco

Telomere length is an independent predictor of survival, treatment requirement and Richter's syndrome transformation in chronic lymphocytic leukemia

Telomere length (TL) has been associated with outcome in chronic lymphocytic leukemia (CLL). The aim of this extensive analysis carried out on 401 CLL patients was to assess TL conclusively as a prognostic biomarker. Our study included two cohorts used as learning (191 patients) and blinded validation series (210 patients). A TL cutoff of 5000 bp was chosen by receiver operating characteristic (ROC) analysis and Youdens index in the learning series. In this series, TL⩽5000 bp was independently associated to a worse outcome for both overall survival (OS; 105.5 vs 281 months, P<0.001) and treatment-free survival (TFS; 24.6 vs 73 months, P<0.001). In the blinded validation series, TL⩽5000 bp was confirmed as an independent outcome predictor for OS (79.8 vs not reached, P<0.001) and TFS (15.2 vs 130.8 months, P<0.001). Moreover, TL⩽5000 bp independently predicted the risk of Richters syndrome (5-year risk: 18.9 vs 6.4%, P=0.016). Within CLL subsets defined by biological predictors, TL consistently identified patient subgroups harboring unfavorable prognosis. These results demonstrate that TL is a powerful independent predictor of multiple outcomes in CLL, and contributes to refine the prognostic assessment of this disease when utilized in combination with other prognostic markers. We thus believe that this prognostic biomarker has the potential for a more widespread use in CLL.

Telomeres and telomerase in normal and malignant B-cells

The telomeric checkpoint is emerging as a critical sensor of cellular damage, playing a major role in human aging and cancer development. In the meantime, telomere biology is rapidly evolving from a basic discipline to a translational branch, capable of providing major hints for biomarker development, risk assessment and targeted treatment of cancer. These advances have a number of implications in the biology of lymphoid tumours. Moreover, there is considerable interest in the potential role of telomeric dysfunction in the wide array of immunological abnormalities, grouped under the definition of ‘immunosenescence’. This review will summarize the impact of recent advances in telomere biology on the physiology and pathology of the B lymphocyte, with special interest in immunosenescence and lymphomagenesis. Copyright

Clinical implications and prognostic role of minimal residual disease detection in follicular lymphoma.

The identification of patients at high risk of relapse is a critical goal of modern translational research in oncohematology. Minimal residual disease (MRD) detection by polymerase chain reaction-based methods is routinely employed in the management of patients with acute lymphoblastic leukemia. Current knowledge indicates that it is also a useful prognostic tool in several mature lymphoproliferative disorders and particularly in follicular lymphoma (FL). Based on this evidence clinical trials employing MRD-based risk stratification are currently ongoing in FL. In this review the ‘state of the art’ of MRD evaluation in FL is discussed. A short description of technical issues and recent methodological advances is provided. Then, the bulk of the review focuses on critical take-home messages for clinicians working in the field. Finally, we discuss future perspectives of MRD detection and more generally outcome prediction in FL.

Telomere loss in Philadelphia-negative hematopoiesis after successful treatment of chronic myeloid leukemia: Evidence for premature aging of the myeloid compartment

Telomere shortening, a well-known marker of aging and cellular stress, occurs under several conditions in the hematopoietic compartment, including aplastic anemia and following iatrogenic noxae. We decided to verify whether pathological telomere erosion also arises in restored Philadelphia-negative (Ph-negative) hematopoiesis following successful treatment of chronic myeloid leukemia (CML). Eighty-one CML patients in complete cytogenetic remission were compared to 76 age-matched healthy subjects. Myeloid cells of CML patients had shorter telomeres than controls (6521 bp vs 7233 bp, p<0.001). This difference was specific for the myeloid compartment, since it was not observed in lymphoid cells (6774 bp vs 6909 bp, p=0.620). Acquired Ph-negative cytogenetic abnormalities (p=0.010), lack of complete molecular remission (p=0.016) and age (p=0.013) were independent predictors of telomere shortening. Telomere dynamics were assessed over a median follow-up period of 22 months. We documented accelerated non-physiological ongoing telomere shortening in 17/59 CML patients (28%). Patients experiencing grade 2-4 hematological toxicity, during CML remission possessed significantly shorter telomeres compared to those lacking toxicity (p=0.005 for any toxicity, p=0.007 for anemia). CML patients suffer from significant and often ongoing telomere stress resulting in premature and selective aging of the myeloid compartment which might have long-term consequences on function and integrity of Ph-negative hematopoiesis.

Lenalidomide in Pretreated Mantle Cell Lymphoma Patients: An Italian Observational Multicenter Retrospective Study in Daily Clinical Practice (the Lenamant Study)

BACKGROUND Mantle cell lymphoma (MCL) has the worst prognosis of B-cell subtypes owing to its aggressive clinical disease course and incurability with standard chemo-immunotherapy. Options for relapsed MCL are limited, although several single agents have been studied. Lenalidomide is available in Italy for patients with MCL based on a local disposition of the Italian Drug Agency. SUBJECTS, MATERIALS, AND METHODS An observational retrospective study was conducted in 24 Italian hematology centers with the aim to improve information on effectiveness and safety of lenalidomide use in real practice. RESULTS Seventy patients received lenalidomide for 21/28 days with a median of eight cycles. At the end of therapy, there were 22 complete responses (31.4%), 11 partial responses, 6 stable diseases, and 31 progressions, with an overall response rate of 47.1%. Eighteen patients (22.9%) received lenalidomide in combination with either dexamethasone (n = 13) or rituximab (n = 5). Median overall survival (OS) was reached at 33 months and median disease-free survival (DFS) at 20 months: 14/22 patients are in continuous complete response with a median of 26 months. Patients who received lenalidomide alone were compared with patients who received lenalidomide in combination: OS and DFS did not differ. Progression-free survivals are significantly different: at 56 months, 36% in the combination group versus 13% in patients who received lenalidomide alone. Toxicities were manageable, even if 17 of them led to an early drug discontinuation. CONCLUSION Lenalidomide therapy for relapsed MCL patients is effective and tolerable even in a real-life context. IMPLICATION FOR PRACTICE Several factors influence treatment choice in relapsed/refractory mantle cell lymphoma (rrMCL), and the therapeutic scenario is continuously evolving. In fact, rrMCL became the first lymphoma for which four novel agents have been approved: temsirolimus, lenalidomide, ibrutinib, and bortezomib. The rrMCL therapeutic algorithm is not so well established because data in the everyday clinical practice are still poor. Lenalidomide for rrMCL patients is effective and tolerable even in a real-life context.

Progressive telomere shortening is part of the natural history of chronic lymphocytic leukaemia and impacts clinical outcome: Evidences from long term follow-up

Many biological markers at diagnosis have improved the prediction of outcome in chronic lymphocytic leukaemia (CLL) (Nabhan et al, 2015). Previous studies on telomere length (TL) have demonstrated that shorter telomeres at diagnosis are associated with poor outcome, along with unmutated IGHV status, high levels of CD38, CD49d and ZAP70 (Grabowski et al, 2005; Roos et al, 2008; Lin et al, 2014; Dos Santos et al, 2015). Moreover, our previous study, on a large CLL population (n = 401), showed that short TL (<5000 bp) at diagnosis is an independent predictor of shorter overall survival (OS), treatment-free survival (TFS) and progression to Richter syndrome (Rossi et al, 2009). Here we report TL dynamics over time and its predictive value in 90 CLL patients with a longer follow-up. Patients from the previous cohort that were willing to donate further samples were analysed. Diagnosis and treatment of CLL were managed according to institutional guidelines, based on the National Cancer Institute (NCI) Working Group (Hallek et al, 2008). Clinical and biological data were recorded (Table SI). All patients provided informed consent. TL was assessed at two time-points; telomere loss over time was calculated in terms of absolute loss, defined as the loss of telomeric DNA (in base pairs, bp) between the first and second determination of TL, and then adjusted for time, as Yearly Loss [YL = absolute loss (bp)/time (months)], in order to limit the bias of different timing in the second sample acquisition among patients. The second TL analysis was performed on peripheral blood mononuclear cells, recovered using density gradient stratification procedure (Ficoll-Hypaque, GE Healthcare, Buckinghanshire, UK), as previously described (Rossi et al, 2009). Genomic DNA was extracted using DNAzol (Invitrogen, Carlsbad, CA, USA). DNA yields and quality were measured by Nanodrop2000 (ThermoScientific, Waltham, MA, USA). TL was determined by Southern blot analysis. Primary end-point was TFS, defined as the time from the first TL evaluation to the time of first treatment. For univariate analyses, the TFS curve was estimated by the Kaplan– Meier method and compared using the log-rank test. TFS was then analysed by the Cox proportional hazards model comparing, by the Wald test, relevant risk factors (Table I). All reported P-values were two-sided, at the 5% significance level. Data were analysed as of June 2016 by R v.3.3.0 (R Foundation for Statistical Computing, Vienna, Austria). Ninety CLL patients from the original series were clinically monitored for a median time of 128 months (range, 21– 336 months). The first TL determination (baseline TL) was assessed at early stage of the disease, while the second, follow-up, determination (FU TL) was not uniform for all patients, with a median time between the two TL measures of 44 months (range: 11 5–231 months). At the time of the second determination, 26 patients had already relapsed after a first-line treatment, while 64 patients were still in Watch and Wait (WW). Among these, 33 progressed and required a treatment between FU TL and the last follow-up. Telomeres were shorter at FU TL compared to baseline TL (median YL 137 bp; range +174 to 1906 bp, P < 0 001). This was particularly evident in IGHV-mutated patients, as compared to unmutated (median YL 205 bp vs. +63 bp; P < 0 05). Patients with longer telomeres at baseline showed