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.

Khorana score and histotype predicts incidence of early venous thromboembolism in non-Hodgkin lymphomas. A pooled-data analysis of 12 clinical trials of Fondazione Italiana Linfomi (FIL).

Current data suggests that the risk of venous thromboembolism (VTE) in patients with non-Hodgkin lymphoma (NHL) is comparable to that observed in patients with solid tumours, although more robust confirmatory analyses are required. With that in mind, we investigated the occurrence of VTE in a pooled analysis of 12 "Fondazione Italiana Linfomi" (FIL) prospective clinical studies. Specifically, we wished to assess the cumulative incidence of VTE in NHL patients, evaluate the predictive value of the Khorana Score (KS), and identify other potential risk factors for VTEs. Data for VTE occurrence were retrieved from study databases and pharmacovigilance reports. Our analysis includes 1717 patients from 12 prospective phase II and III trials, including newly diagnosed NHL. We observed 53 VTEs (any grade) in 46 patients, with 20 severe VTEs in 17 patients. The cumulative incidences for "all-grade" or grade ≥3 VTEs were 2.9 % (95 % CI: 2.1-3.8) and 1.1 % (95 % CI: 0.6-1.6), respectively. KS categories were positively associated with the risk of VTE of any grade, and with severe events (i. e. grade ≥3; Gray's test p-values = 0.048 and 0.012, respectively). Among NHL patients, those with diffuse large B-cell lymphoma (DLBCL) showed a greater risk of (any grade) VTE (HR: 3.42, 95 % CI: 1.32-8.84, p-value = 0.011). Our study indicates that 1) VTE is a relevant complication for NHL patients, 2) KS is predictive of VTE events and 3) DLBCL histotype is an independent risk factor for VTE incidence, for which preventative interventions could be considered.

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.

Rituximab-based pre-emptive treatment of molecular relapse in follicular and mantle cell lymphoma.

Pre-emptive rituximab (pRTX) might represent an effective approach for patients with follicular (FL) and mantle cell lymphoma (MCL) experiencing molecular relapse (M-rel). However, available experience is still limited. We retrospectively collected FL and MCL cases that underwent pRTX with four weekly rituximab infusions (375 mg/m²) due to molecular persistence or M-rel. M-rel was assessed using nested polymerase chain reaction (PCR) and real-time quantitative PCR using the Bcl-1/IGH, Bcl-2/IGH or the immunoglobulin heavy chain rearrangement. Twenty-three occurrences of M-rel or persistence were treated in 18 patients (nine MCL and nine FL). The pRTX reinduced molecular remission (MR) in 17/23 cases (7/9 FL and 10/14 MCL). The median time to MR reinduction was 4.5 months (range 3-12), and the median duration of the first MR reinduction was 34 months (range 12-72). In five MCL cases, pRTX was used to treat subsequent M-rels, with success in four cases. No clinical relapses were seen within 2 years of successful reinduction of MR. Progression-free survival after pRTX was 64 % at a median follow-up of 6 years. pRTX was feasible and safe and effectively reinduced MR in FL and MCL patients (74 %). Prospective trials are needed to verify the clinical benefit of similar approaches.

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.

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.