David Sibon

18F-FDG PET/CT bone/bone marrow findings in Hodgkin’s lymphoma may circumvent the use of bone marrow trephine biopsy at diagnosis staging

PurposeAccurate staging of Hodgkin’s lymphoma (HL) is necessary in selecting appropriate treatment. Bone marrow trephine biopsy (BMB) is the standard procedure for depicting bone marrow involvement. BMB is invasive and explores a limited part of the bone marrow. 18F-FDG PET/CT is now widely used for assessing response to therapy in HL and a baseline study is obtained to improve accuracy. The aim of this retrospective analysis was to assess whether routine BMB remains necessary with concomitant 18F-FDG PET/CT.MethodsData from 83 patients (newly diagnosed HL) were reviewed. All patients had received contrast-enhanced CT, BMB and 18F-FDG PET/CT. Results of BMB were not available at the time of 18F-FDG PET/CT imaging.ResultsSeven patients had lymphomatous involvement on BMB. Four patients had bone involvement on conventional CT (two with negative BMB). All patients with bone marrow and/or bone lesions at conventional staging were also diagnosed on 18F-FDG PET/CT scan. PET/CT depicted FDG-avid bone/bone marrow foci in nine additional patients. Four of them had only one or two foci, while the other had multiple foci. However, the iliac crest, site of the BMB, was not involved on 18F-FDG PET/CT. Osteolytic/sclerotic lesions matching FDG-avid foci were visible on the CT part of PET/CT in three patients. MRI ordered in three other patients suggested bone marrow involvement. Interim and/or end-therapy 18F-FDG PET/CT documented response of FDG-avid bone/bone marrow foci to chemotherapy in every patient.Conclusion18F-FDG PET/CT highly improves sensitivity for diagnosis of bone/bone marrow lesions in HL compared to conventional staging.

Life without Peripheral Serotonin: Insights from Tryptophan Hydroxylase 1 Knockout Mice Reveal the Existence of Paracrine/ Autocrine Serotonergic Networks

Since its identification, 75 years ago, the monoamine serotonin (5-HT) has attracted considerable attention toward its role as a neurotransmitter in the central nervous system. Yet, increasing evidence, from a growing number of research groups, substantiates the fact that 5-HT regulates important nonneuronal functions. Peripheral 5-HT, synthesized by the enzyme tryptophan hydroxyase (Tph) in intestinal cells, was assumed to be distributed throughout the entire body by blood platelets and to behave as a pleiotropic hormone. A decade ago, generation of a mouse model devoid of peripheral 5-HT lead to the discovery of a second isoform of the enzyme Tph and also suggested that 5-HT might act as a local regulator in various organs. The objective of this review is to highlight the newly discovered functions played by the monoamine using the Tph1 KO murine model and to outline current findings that led to the discovery of complete serotonergic systems in unexpected organs. Within an organ, both the presence of local Tph enzymatic activity and serotonergic components are of particular importance as they support the view that 5-HT meets the criteria to be qualified as a monoamine with a paracrine/autocrine function.

Early posttransplantation donor-derived invariant natural killer T-cell recovery predicts the occurrence of acute graft-versus-host disease and overall survival

Invariant natural killer T (iNKT) cells can experimentally dissociate GVL from graft-versus-host-disease (GVHD). Their role in human conventional allogeneic hematopoietic stem cell transplantation (HSCT) is unknown. Here, we analyzed the post-HSCT recovery of iNKT cells in 71 adult allografted patients. Results were compared with conventional T- and NK-cell recovery and correlated to the occurrence of GVHD, relapse, and survival. We observed that posttransplantation iNKT cells, likely of donor origin, recovered independently of T and NK cells in the first 90 days after HSCT and reached greater levels in recipient younger than 45 years (P = .003) and after a reduced-intensity conditioning regimen (P = .03). Low posttransplantation iNKT/T ratios (ie, < 10(-3)) were an independent factor associated with the occurrence of acute GVHD (aGVHD; P = .001). Inversely, reaching iNKT/T ratios > 10(-3) before day 90 was associated with reduced nonrelapse mortality (P = .009) without increased risk of relapse and appeared as an independent predictive factor of an improved overall survival (P = .028). Furthermore, an iNKT/T ratio on day 15 > 0.58 × 10(-3) was associated with a 94% risk reduction of aGVHD. These findings provide a proof of concept that early postallogeneic HSCT iNKT cell recovery can predict the occurrence of aGVHD and an improved overall survival.

HTLV-1 propels untransformed CD4+ lymphocytes into the cell cycle while protecting CD8+ cells from death

Human T cell leukemia virus type 1 (HTLV-1) infects both CD4+ and CD8+ lymphocytes, yet it induces adult T cell leukemia/lymphoma (ATLL) that is regularly of the CD4+ phenotype. Here we show that in vivo infected CD4+ and CD8+ T cells displayed similar patterns of clonal expansion in carriers without malignancy. Cloned infected cells from individuals without malignancy had a dramatic increase in spontaneous proliferation, which predominated in CD8+ lymphocytes and depended on the amount of tax mRNA. In fact, the clonal expansion of HTLV-1-positive CD8+ and CD4+ lymphocytes relied on 2 distinct mechanisms--infection prevented cell death in the former while recruiting the latter into the cell cycle. Cell cycling, but not apoptosis, depended on the level of viral-encoded tax expression. Infected tax-expressing CD4+ lymphocytes accumulated cellular defects characteristic of genetic instability. Therefore, HTLV-1 infection establishes a preleukemic phenotype that is restricted to CD4+ infected clones.

Antiviral therapy is associated with a better survival in patients with hepatitis C virus and B-cell non-Hodgkin lymphomas, ANRS HC-13 lympho-C study

Hepatitis C virus (HCV) infection increases the risk of B‐cell non‐Hodgkin lymphomas (B‐NHL). Antiviral treatment (AT) can induce hematological responses in patients with marginal zone lymphomas (MZL). The ANRS HC‐13 Lympho‐C study aimed at a better understanding of the impact of AT on HCV associated B‐NHL. This multicentric study enrolled 116 HCV‐positive patients with B‐NHL between 2006 and 2012. Cytological and histological samples were collected for centralized review. At lymphoma diagnosis, median age was 61 years and gender ratio M/F was 1. Cytohistological distribution was marginal zone lymphoma (MZL) n = 45 (39%), diffuse large B‐cell lymphoma (DLBCL) n = 45 (39%), and other types n = 26 (22%). MZL patients had more frequent detection of rheumatoid factor (68% vs. 35%; P = 0.001) and more frequently mixed cryoglobulinemia (74% vs. 44%; P = 0.021) than patients with DLBCL. Among patients receiving AT, a sustained virologic response was achieved in 23 of 38 (61%) patients with MZL and in 9 of 17 (53%) with DLBCL (P = 0.42). Three‐year overall survival (OS) and progression‐free survival were 78% 95%CI [63–88] and 64% [48–76], respectively, without difference between cytohistological groups. Outcome analysis showed a favorable association between OS and AT in all patients (P = 0.05) and in the subgroup of MZL patients only (P = 0.04). Our data support that AT improves the outcomes of HCV‐associated NHLs. The impact of new AT regimen with protease inhibitor needs to be investigated in this setting. [clinicalTrials.gov Identification number NCT01545544] Am. J. Hematol. 90:197–203, 2015.

Lenalidomide in lower-risk myelodysplastic syndromes with karyotypes other than deletion 5q and refractory to erythropoiesis-stimulating agents

Lenalidomide (LEN) has been shown to yield red blood cell (RBC) transfusion independence in about 25% of lower risk myelodysplastic syndromes (MDS) without del(5q), but its efficacy in patients clearly refractory to erythropoiesis‐stimulating agents (ESA) is not known. We report on 31 consecutive lower‐risk non‐del(5q) MDS patients with anaemia refractory to ESA and treated with LEN in a compassionate programme, 20 of whom also received an ESA. An erythroid response was obtained in 15 patients (48%), including 10 of the 27 (37%) previously transfusion‐dependent (RBC‐TD) patients, who became transfusion‐independent (RBC‐TI). Nine of the responders relapsed, whereas 6 (40%) were still responding and transfusion‐free after 11+–31+ months. Median response duration was 24 months. The erythroid response rate was lower in refractory cytopenia with multilineage dysplasia (27% vs. 60%) and tended to be higher in patients treated with LEN + ESA (55% vs. 36%). Response duration was significantly longer in responders who obtained RBC‐TI and in patients treated with LEN after primary resistance to ESA. The main toxicity of LEN was cytopenias. We confirm that, in a patient population of lower risk MDS without del 5q clearly resistant to ESA, LEN is an interesting second line therapeutic option. Its combination with ESAs in this context warrants prospective studies.

Fate of premalignant clones during the asymptomatic phase preceding lymphoid malignancy.

Almost all cancers are preceded by a prolonged period of clinical latency during which a combination of cellular events helps move carcinogen-exposed cells towards a malignant phenotype. Hitherto, investigating the fate of premalignant cells in vivo remained strongly hampered by the fact that these cells are usually indistinguishable from their normal counterparts. Here, for the first time, we have designed a strategy able to reconstitute the replicative history of the bona fide premalignant clone in an animal model, the sheep experimentally infected with the lymphotropic bovine leukemia virus. We have shown that premalignant clones are early and clearly distinguished from other virus-exposed cells on the basis of their degree of clonal expansion and genetic instability. Detectable as early as 0.5 month after the beginning of virus exposure, premalignant cells displayed a two-step pattern of extensive clonal expansion together with a mutation load approximately 6 times higher than that of other virus-exposed cells that remained untransformed during the life span of investigated animals. There was no fixation of somatic mutations over time, suggesting that they regularly lead to cellular death, partly contributing to maintain a normal lymphocyte count during the prolonged premalignant stage. This equilibrium was finally broken after a period of 18.5 to 60 months of clinical latency, when a dramatic decrease in the genetic instability of premalignant cells coincided with a rapid increase in lymphocyte count and lymphoma onset.

Combined ifosfamide, etoposide and oxalipatin chemotherapy, a low-toxicity regimen for first-relapsed or refractory Hodgkin lymphoma after ABVD/EBVP: a prospective monocentre study on 34 patients.

Around 20% of Hodgkin lymphoma (HL) patients are refractory to first‐line therapy with ABVD (adriamycin–bleomycin–vinblastine–dacarbazine) or relapse after complete remission. Salvage regimens frequently have delayed courses or require dose‐reduction because of haemotoxicity. We evaluated the IVOx (ifosfamide–etoposide–oxaliplatin) salvage regimen in terms of response rate, toxicity and stem‐cell mobilization. Thirty‐four patients with relapsed/refractory HL after anthracycline‐containing chemotherapy prospectively received IVOx, consisting of ifosfamide (1500 mg/m2 days 1–3), etoposide (150 mg/m2 days 1–3) and oxaliplatin (130 mg/m2 day 1). Patients <65 years old received high‐dose therapy followed by autologous stem‐cell transplantation (HDT–ASCT). Response was assessed by computed and positron‐emission tomographies. Overall and complete response rates were 76% and 32%, respectively, after 2 cycles. Three episodes of febrile neutropenia occurred, and three patients required dose‐reductions. Twenty‐six patients underwent HDT–ASCT. With median follow‐up at 5 years, the 5‐year overall and event‐free survival rates were 74% and 63%, respectively. IVOx is a well‐tolerated outpatient regimen for relapsed HL, that does not hamper stem‐cell mobilization, achieves good response rates and compares favourably with previously published salvage regimens.

Single or tandem autologous stem-cell transplantation for first-relapsed or refractory Hodgkin lymphoma: 10-year follow-up of the prospective H96 trial by the LYSA/SFGM-TC study group

We assessed the long-term results of autologous stem-cell transplantation for patients with first-relapsed or refractory Hodgkin lymphoma included in the prospective Lymphoma Study Association/Société Française de Greffe de Moelle H96 trial. This large multicenter phase II trial evaluated a risk-adapted strategy with single or tandem autologous stem-cell transplantation for 245 Hodgkin lymphoma patients. Poor-risk patients (n=150) had primary refractory Hodgkin lymphoma (n=77) or ≥2 risk factors at first relapse (n=73) and were eligible for tandem autologous stem-cell transplantation. Intermediate-risk patients (n=95) had one risk factor at first relapse and were eligible for single autologous stem-cell transplantation. With a median follow-up of 10.3 years, 10-year freedom from second failure and overall survival rates were, respectively: 64% (95% CI, 54% to 74%) and 70% (95% CI, 61% to 80%) for the intermediate-risk group, and 41% (95% CI, 33% to 49%) and 47% (95% CI, 39% to 55%) for the poor-risk group. Considering only patients who did not relapse after completing autologous stem-cell transplantation, the 15-year cumulative incidences of second primary malignancies were 24% for the 70 intermediate-risk patients and 2% for the 75 poor-risk ones. With long-term follow-up, the risk-adapted strategy remains appropriate. Tandem autologous stem-cell transplantation can still be considered an option for poor-risk patients, but integration of positron-emission tomography findings and new drugs may help to refine the need for a second autologous stem-cell transplant and possibly improve outcomes of patients with first-relapsed or refractory Hodgkin lymphoma.

Clinical Trials of Adult T-Cell Leukaemia/Lymphoma Treatment

Adult T-cell leukaemia/lymphoma (ATLL) is an aggressive malignancy of mature activated T cells caused by human T-cell lymphotropic virus type I (HTLV-1). Prognosis is severe because of intrinsic chemoresistance and severe immuosuppression. Four different subtypes are described with different outcomes, and treatment strategies vary according to the different clinical courses. Japanese trials show that combinations of chemotherapy can increase the response rates especially in the lymphoma subtype. However, patients have a high rate of relapse and the outcome remains extremely poor. Recently, a worldwide meta-analysis demonstrated that the combination of Zidovudine and Interferon-alpha (IFN) is effective in the leukemic subtypes (smoldering, chronic, and acute) and influences favorably the course of the disease. In order to prevent relapse, clinical trials testing new drugs such as monoclonal antibodies or combinations such as arsenic/IFN are needed. Finally, allogeneic stem cell transplantation is a feasible option but bears a very high rate of complications.