Noncanonical effector functions of the T-memory-like T-PLL cell are shaped by cooperative TCL1A and TCR signaling

T-cell prolymphocytic leukemia (T-PLL) is a poor-prognostic neoplasm. Differentiation stage and immune-effector functions of the underlying tumor cell are insufficiently characterized. Constitutive activation of the T-cell leukemia 1A (TCL1A) oncogene distinguishes the (pre)leukemic cell from regular postthymic T cells. We assessed activation-response patterns of the T-PLL lymphocyte and interrogated the modulatory impact by TCL1A. Immunophenotypic and gene expression profiles revealed a unique spectrum of memory-type differentiation of T-PLL with predominant central-memory stages and frequent noncanonical patterns. Virtually all T-PLL expressed a T-cell receptor (TCR) and/or CD28-coreceptor without overrepresentation of specific TCR clonotypes. The highly activated leukemic cells also revealed losses of negative-regulatory TCR coreceptors (eg, CTLA4). TCR stimulation of T-PLL cells evoked higher-than-normal cell-cycle transition and profiles of cytokine release that resembled those of normal memory T cells. More activated phenotypes and higher TCL1A correlated with inferior clinical outcomes. TCL1A was linked to the marked resistance of T-PLL to activation- and FAS-induced cell death. Enforced TCL1A enhanced phospho-activation of TCR kinases, second-messenger generation, and JAK/STAT or NFAT transcriptional responses. This reduced the input thresholds for IL-2 secretion in a sensitizer-like fashion. Mice of TCL1A-initiated protracted T-PLL development resembled such features. When equipped with epitope-defined TCRs or chimeric antigen receptors, these Lckpr-hTCL1Atg T cells gained a leukemogenic growth advantage in scenarios of receptor stimulation. Overall, we propose a model of T-PLL pathogenesis in which TCL1A enhances TCR signals and drives the accumulation of death-resistant memory-type cells that use amplified low-level stimulatory input, and whose loss of negative coregulators additionally maintains their activated state. Treatment rationales are provided by combined interception in TCR and survival signaling.

Increased body mass index is associated with improved overall survival in diffuse large B-cell lymphoma

BACKGROUND

Obesity is a well-known risk factor for the development of several types of cancer including lymphomas, but its influence on the course of disease is fairly unknown. Recently, a retrospective cancer registry analysis demonstrated significantly prolonged survival for overweight and obese patients with diffuse large B-cell lymphoma (DLBCL). The study population almost exclusively consisted of male US American patients of lower socioeconomic status and one-fifth of patients received cyclophosphamide, doxorubicin, vincristine, prednisone (CHOP) chemotherapy without rituximab. Therefore, it remains unclear if these results can be extrapolated to the general DLBCL population.

PATIENTS AND METHODS

This retrospective single-center analysis included 183 unselected DLBCL patients who were treated with rituximab and standard-dosed anthracycline-based chemoimmunotherapy as first-line therapy between January 2004 and December 2012. Patients were stratified by body mass index (BMI) into 'low BMI' (<25.0 kg/m(2)) and 'high BMI' (≥25.0 kg/m(2)).

RESULTS

The two groups were well balanced regarding age, performance score, international prognostic index, B-symptoms and extranodal involvement. However, there was a trend for male sex (P = 0.053) and higher-stage disease (P = 0.066) in the high-BMI group. Patients with higher BMI had significantly longer overall survival (OS; hazard ratio [HR] 0.546; P = 0.035) with 80.9% of patients alive at 3 years versus 64.2% in the low-BMI group. BMI was also an independent prognostic factor for OS in multivariate analysis (HR 0.557; P = 0.043).

CONCLUSION

We could show a significant association between overweight/obesity and improved OS in an unselected DLBCL cohort.

Alemtuzumab in chronic lymphocytic leukemia: final results of a large observational multicenter study in mostly pretreated patients

This retrospective study evaluated the benefit of alemtuzumab monotherapy in unselected patients with advanced B-cell chronic lymphocytic leukemia (CLL) and prolymphocytic leukemia (B-PLL) to definitely describe the impact of this antibody in clinical routine use. Data were collected from 208 consecutive, mainly pretreated, patients with CLL (n = 202), and B-PLL (n = 6) who had received alemtuzumab. Response, progression-free survival (PFS), and overall survival (OS) in various settings were assessed, and toxicities were documented. In these routine patients, a comparably low cumulative dose of alemtuzumab (median, 403 mg) was applied. In CLL, overall response rate was 32 %, and various pre-therapeutic parameters were predictive for inferior response, among them, the prior administration of ≥3 therapy lines (P < 0.001), refractoriness to fludarabine (P = 0.002), and bulky lymphadenopathy (P = 0.003). PFS and OS after start of alemtuzumab were 6.2 and 21.0 months, respectively. Bulky lymphadenopathy was the prominent risk factor for both inferior PFS (P < 0.001) and OS (P = 0.002). In B-PLL, four patients experienced a fatal outcome, whereas two patients had some benefit with alemtuzumab. The main adverse effects were CMV reactivation (20 %) and a broad spectrum of infections, which together were the main reasons for treatment interruption and/or premature termination. In conclusion, alemtuzumab administered even at low dose levels was effective but overall considerably toxic in routine CLL patients. We emphasize that alemtuzumab remains an important therapeutic option in subsets of CLL patients.

Addition of rituximab to fludarabine and cyclophosphamide in patients with chronic lymphocytic leukaemia: a randomised, open-label, phase 3 trial

BACKGROUND

On the basis of promising results that were reported in several phase 2 trials, we investigated whether the addition of the monoclonal antibody rituximab to first-line chemotherapy with fludarabine and cyclophosphamide would improve the outcome of patients with chronic lymphocytic leukaemia.

METHODS

Treatment-naive, physically fit patients (aged 30-81 years) with CD20-positive chronic lymphocytic leukaemia were randomly assigned in a one-to-one ratio to receive six courses of intravenous fludarabine (25 mg/m(2) per day) and cyclophosphamide (250 mg/m(2) per day) for the first 3 days of each 28-day treatment course with or without rituximab (375 mg/m(2) on day 0 of first course, and 500 mg/m(2) on day 1 of second to sixth courses) in 190 centres in 11 countries. Investigators and patients were not masked to the computer-generated treatment assignment. The primary endpoint was progression-free survival (PFS). Analysis was by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00281918.

FINDINGS

408 patients were assigned to fludarabine, cyclophosphamide, and rituximab (chemoimmunotherapy group) and 409 to fludarabine and cyclophosphamide (chemotherapy group); all patients were analysed. At 3 years after randomisation, 65% of patients in the chemoimmunotherapy group were free of progression compared with 45% in the chemotherapy group (hazard ratio 0·56 [95% CI 0·46-0·69], p<0·0001); 87% were alive versus 83%, respectively (0·67 [0·48-0·92]; p=0·01). Chemoimmunotherapy was more frequently associated with grade 3 and 4 neutropenia (136 [34%] of 404 vs 83 [21%] of 396; p<0·0001) and leucocytopenia (97 [24%] vs 48 [12%]; p<0·0001). Other side-effects, including severe infections, were not increased. There were eight (2%) treatment-related deaths in the chemoimmunotherapy group compared with ten (3%) in the chemotherapy group.

INTERPRETATION

Chemoimmunotherapy with fludarabine, cyclophosphamide, and rituximab improves progression-free survival and overall survival in patients with chronic lymphocytic leukaemia. Moreover, the results suggest that the choice of a specific first-line treatment changes the natural course of chronic lymphocytic leukaemia.

FUNDING

F Hoffmann-La Roche.

Clinicopathogenetic significance of chromosomal abnormalities in patients with blastic peripheral B-cell lymphoma. Kiel-Wien-Lymphoma Study Group

So far, reproducible histomorphologic and immunological criteria to distinguish clinicopathologic subtypes of blastic peripheral B-cell non-Hodgkin's lymphoma (BBCL), especially centroblastic (cb) and immunoblastic (ib) lymphomas, for daily diagnostic use are still lacking. Therefore, we correlated the cytogenetic findings in 126 patients with BBCL with histopathologic diagnoses. Subclassification of cb and ib lymphomas relied on the criteria defined in the updated Kiel classification; these subtypes are also listed in the Revised European-American Lymphoma (REAL) classification and in a preliminary report on the newly established World Health Organization classification, to investigate their clinical significance. Moreover, we performed a multivariate analysis to compare the prognostic significance of cytogenetic findings with the International Index. There were significant differences in the frequency of chromosome aberrations between different BBCL subtypes: t(8;14) was predominantly present in Burkitt's lymphomas, t(14;18) in centroblastic lymphomas, deletions in 8q and 14q, changes of 4q and losses of chromosome 10 in immunoblastic lymphomas; t(11;14) was restricted to blastoid mantle cell lymphomas and associated with a poor prognosis. In cb lymphomas, deletions in 1q42-qter, duplications in 1q23-32, trisomy 5, and changes of 15q were identified as independent prognostic factors. In ib lymphomas, changes of 7q and 8q had stronger impact on survival than the International Index. These findings underline that Burkitt's, cb, ib, and blastoid mantle-cell lymphoma are biologically distinct and clinically relevant entities and that cytogenetic findings can be helpful to subtype BBCL.

Outcome of patients with low-grade B cell non-Hodgkin lymphoma and initial bone marrow involvement: data of a single institution

We evaluated 1179 consecutive patients with low-grade B-NHL diagnosed according to criteria of the Kiel classification and presenting with initial bone marrow involvement. Therapeutic approaches were not changed during the observation period 1975-1995. CLL (n=895) and IC (n=169) were treated palliatively with chlorambucil/prednisone or prednimustine. In CBCC (n=65) and CC (n=50) remission was induced with COP or CHOP. The overall response rate was 67%, but only 35% of CBCC and 23% of CC patients achieved complete remission. Median survival was 64 months in CBCC and 28 months in CC. As the median age of our patient population was 68 years (range: 23-93) it seems doubtful whether overall prognosis can be improved by aggressive therapeutic measures. One exception might be CBCC patients who were younger (median age 56 years) and who were usually in good general condition so that they might qualify for high dosage chemotherapy and stem cell support. Whether the prognosis of IC and CLL (median survival 74 months and 107 months, respectively) can be improved by treatment with drugs such as purine analogs will depend on the long-term outcome of clinical studies.

Ifosfamide, mitoxantrone and etoposide (VIM) as salvage therapy of low toxicity in non-Hodgkin's lymphoma

Patients with non-Hodgkin's lymphoma (NHL) who fail to respond to first-line treatment or relapse after having shown complete or partial remission have a poor prognosis, especially in high-grade NHL. Several salvage regimens show considerable toxicity and a poor long-term outcome. In this retrospective study we analyzed data of 55 patients (34 men and 21 women) with a median age of 66 years (range: 18-89). The combination chemotherapy (VIM) consisted of VP-16 (etoposide) 65 mg/m2, ifosfamide 650 mg/m2 and mitoxantrone 3 mg/m2 and was administered on 3 consecutive days along with mesna as uroprotection. Patients were treated for refractory disease or relapse and did not qualify for high-dose chemotherapy and ABMT. Stages according to the An Arbor classification were: stage I/16, II/4, III/8 and IV/37 patients. Thirty-three patients suffered from high-grade and 22 from low-grade NHL. Toxicity (WHO recommendations) was very mild. High-grade NHL showed a better response rate (18/33, 46%) than low-grade NHL (7/22, 36%). Overall response was 41% (12 CR and 11 PR) with a median duration of 36 months (range: 6-57 months). The combination therapy investigated exhibits mild toxicity even in extensively pretreated or elderly patients. The overall response rate of 41% might be improved by increased dosage and growth factor support.