Long-term survival of patients with mantle cell lymphoma after autologous haematopoietic stem-cell transplantation in first remission: a post-hoc analysis of an open-label, multicentre, randomised, phase 3 trial.

BACKGROUND: Autologous haematopoietic stem-cell transplantation (HSCT) in first remission is the current standard treatment in fit patients with mantle cell lymphoma. In this long-term follow-up study, we aimed to evaluate the efficacy of autologous HSCT versus interferon alfa maintenance after chemotherapy without or with rituximab in patients with primary advanced-stage mantle cell lymphoma. METHODS: We did a post-hoc, long-term analysis of an open-label, multicentre, randomised, phase 3 trial done in 121 participating hospitals or practices across six European countries. Patients who were aged 18-65 years with previously untreated stage III-IV mantle cell lymphoma and an ECOG performance score of 0-2 were eligible for participation. Patients were randomly assigned (1:1) to receive either myeloablative radiochemotherapy (fractionated total body irradiation with 12 Gy/day 6-4 days before autologous HSCT and cyclophosphamide 60 mg/kg per day intravenously 3-2 days before autologous HSCT) followed by autologous HSCT (the autologous HSCT group) or interferon alfa maintenance (the interferon alfa maintenance group; 6 × 106 IU three times a week subcutaneously until progression) after completion of CHOP-like induction therapy (cyclophosphamide 750 mg/m2 intravenously on day 1, doxorubicin 50 mg/m2 intravenously on day 1, vincristine 1·4 mg/m2 [maximum 2 mg] intravenously on day 1, and prednisone 100 mg/m2 orally on days 1-5; repeated every 21 days for up to 6 cycles) without or with rituximab (375 mg/m2 intravenously on day 0 or 1 of each cycle; R-CHOP). The primary outcome was progression-free survival from end of induction until progression or death among patients who had a remission and the secondary outcome was overall survival from the end of induction until death from any cause. We did comparisons of progression-free survival and overall survival according to the intention-to-treat principle between both groups among responding patients and explored efficacy in subgroups according to induction treatment without or with rituximab. Hazard ratios (HRs) were adjusted for the mantle cell lymphoma international prognostic index (MIPI) numerical score, and in the total group also for rituximab use (adjusted HR [aHR]). This trial was started before preregistration was implemented and is therefore not registered, recruitment is closed, and this is the final evaluation. FINDINGS: Between Sept 30, 1996, and July 1, 2004, 269 patients were randomly assigned to receive either autologous HSCT or interferon alfa maintenance therapy. The median follow-up was 14 years (IQR 10-16), with the intention-to-treat population consisting of 174 patients (93 [53%] in the autologous HSCT group and 81 [47%] in the interferon alfa maintenance group) who responded to induction therapy. The median age was 55 years (IQR 47-60), and R-CHOP was used in 68 (39%) of 174 patients. The median progression-free survival was 3·3 years (95% CI 2·5-4·3) in the autologous HSCT group versus 1·5 years (1·2-2·0) in the interferon alfa maintenance group (log-rank p<0·0001; aHR 0·50 [95% CI 0·36-0·69]). The median overall survival was 7·5 years (95% CI 5·7-12·0) in the autologous HSCT group versus 4·8 years (4·0-6·6) in the interferon alfa maintenance group (log-rank p=0·019; aHR 0·66 [95% CI 0·46-0·95]). For patients treated without rituximab, the progression-free survival adjusted HR for autologous HSCT versus interferon alfa was 0·40 (0·26-0·61), in comparison to 0·72 (0·42-1·24) for patients treated with rituximab. For overall survival, the adjusted hazard ratio for HSCT versus interferon alfa was 0·52 (0·33-0·82) without rituximab and 1·05 (0·55-1·99) for patients who received rituximab. INTERPRETATION: Our results confirm the long-term efficacy of autologous HSCT to treat mantle cell lymphoma established in the pre-rituximab era. The suggested reduced efficacy after immunochemotherapy supports the need for its re-evaluation now that antibody maintenance, high-dose cytarabine, and targeted treatments have changed the standard of care for patients with mantle cell lymphoma. FUNDING: Deutsche Krebshilfe, the European Community, and the Bundesministerium für Bildung und Forschung, Kompetenznetz Maligne Lymphome.

Impact of age on clinical risk scores in follicular lymphoma.

The Follicular Lymphoma (FL) International Prognostic Index (FLIPI) and FLIPI-2 are well-described clinical risk models. Age >60 years at diagnosis is a risk factor in both scores. Recently, we showed that older age is not associated with higher risk of disease progression or inferior treatment efficacy. Instead, shorter survival of older patients results mainly from an increased risk of nonrelapse deaths. This questions the value of age as a meaningful component of scores intended to predict disease-specific survival. The newly proposed PRIMA-prognostic index (PRIMA-PI) only includes ß2-microglobulin levels and bone marrow infiltration as risk factors. Here, we independently validate the PRIMA-PI in a clinical trial cohort of 475 patients with advanced FL who uniformly received cyclophosphamide, doxorubicin hydrochloride, vincristine sulfate, prednisone, and rituximab (R-CHOP) as frontline therapy. The PRIMA-PI separated 3 similar sized risk cohorts with 5-year progression-free survival (PFS) rates of 74%, 59%, and 39%, respectively (P < .0001). Furthermore, we compare the PRIMA-PI with the FLIPI and FLIPI-2. We demonstrate that the PRIMA-PI has the highest specificity to identify high-risk patients (80% for 5-year PFS) because of its superior risk stratification in patients >60 years (73% vs 33% [FLIPI] and 47% [FLIPI-2] for 5-year PFS). Thus, the PRIMA-PI is a promising clinical tool to stringently identify patients at highest risk of poor outcome after frontline R-CHOP for advanced FL, and is particularly useful in patients with older age. Further validation in non-R-CHOP treated cohorts is needed.

Transient antagonism of anti-CD20 monoclonal antibodies and PI3K inhibitor idelalisib in DLBCL cell lines.

INTRODUCTION: PI3K inhibitors are evaluated for relapsed and refractory Diffuse large B-cell lymphoma (DLBCL) patients. OBJECTIVE: As rituximab has shown to influence B-cell receptor (BCR) signaling, we investigated the interaction of anti-CD20 antibody rituximab and the new type II glycoengineered anti-CD20 antibody obinutuzumab in combination with the PI3K delta inhibitor idelalisib. METHODS: Established DLBCL cell lines were treated with either rituximab or obinutuzumab alone or in combination with PI3K delta inhibitor idelalisib. RESULTS: Rituximab and to a lesser extent obinutuzumab monotherapy resulted in a temporary upregulation of p-Akt, p42/44, and p38 signaling pathways. Idelalisib reduced p-Akt expression. Rituximab antagonized the p-Akt downregulation at early time points, while obinutuzumab did not interfere with idelalisib's effects. In cell growth analysis, early antagonism could also be detected. CONCLUSION: The combination of idelalisib with CD antibodies shows an initial antagonism of rituximab but not obinutuzumab in downregulation of PI3K-signaling targets.

Occurrence, risk factors and outcome of adenovirus infection in adult recipients of allogeneic hematopoietic stem cell transplantation.

BACKGROUND: Adenovirus (ADV) infections can have a high mortality in immunocompromised patients and are difficult to treat. OBJECTIVES AND STUDY DESIGN: We retrospectively analyzed occurrence and risk factors of ADV infection in 399 adults with hematological disorders undergoing hematopoietic stem cell transplantation (allo-HSCT), focusing on alternative donor transplantation (ADT) and disseminated disease. RESULTS: ADV infection occurred in 42 patients (10.5%). Disease was localized in 18 and disseminated in 6 patients. ADV infection was observed in 15% after ADT, performed in 29% of all recipients, and was less frequent (6%) in T-cell-replete (TCR) haploidentical transplantation using post-transplantation cyclophosphamide (PTCY) than in other ADT protocols. Lower age, the use of alternative donor grafts and acute graft-versus-host disease (GvHD)≥grade II were risk factors for ADV infection. After failure of standard antiviral treatment, three patients with disseminated ADV disease received one dose of ADV-specific T cells, resulting in virological response in 2/3 patients, clearance of ADV viremia in 2/2 patients, and survival of 1/3 patients; both patients with pneumonia died. CONCLUSIONS: ADV infection was of moderate occurrence in our adult recipients of allo-HSCT despite a high proportion of potential high-risk patients receiving ADT. TCR strategies using PTCY might limit ADV complications in haploidentical transplantation. Despite feasible adoptive therapy strategies, outcome of disseminated disease remains dismal.

Altered treatment of chronic lymphocytic leukemia in Germany during the last decade.

Chronic lymphocytic leukemia (CLL) is the most common subtype of adult leukemia in the western world. We here report a nationwide survey monitoring the treatment decisions concerning CLL patients in Germany in 2011 and compare treatment trends to sequential surveys performed previously during the last decade. The rate of patients diagnosed in early stages (Binet A/B) notably increased (2006: 66 %, 2009: 71 %, 2011: 77 %) over the years. From 2006 to 2009, the most frequent applied regime switched from chlorambucil to fludarabine containing regimes (2006 chlorambucil: 32 %, 2009: 14 %, fludarabine 2006: 23 %, 2009: 37 %). In 2011, the combination of rituximab with bendamustine (31 %) was most frequent used followed by the rituximab-fludarabine-cyclophosphamide (22 %) regime. Further, immune-chemotherapies were administered significantly more often over the observation period (2006: 15 %, 2011: 73 %). Taken together, this data reflects the change of treatment strategies over the last decade in clinical reality.

Temsirolimus acts as additive with bendamustine in aggressive lymphoma.

The mammalian target of rapamycin (mTOR) is a protein kinase involved in the phosphatidylinositol 3-kinase (PI3K)/AKT signalling pathway. It plays a pivotal role in the control of cell proliferation, survival, and angiogenesis with multiple and frequent dysregulations of this pathway in human tumors. Temsirolimus is an intravenous drug, specifically inhibiting the mTOR pathway. Bendamustine is well known for its clinical activity in indolent non-Hodgkin-lymphoma (NHL) and has lately shown clinical activity in mantle cell lymphoma (MCL). Here, we present a case report of temsirolimus in combination with bendamustine and rituximab leading to a CR in a pretreated male. In addition, our in vitro data underlines the additive and synergistic efficacy in cell growth reduction of temsirolimus combined with bendamustine in MCL cell lines and in DLBCL cell lines. Furthermore, as an underlying mechanism of this additive, effects on cell cycle inhibition and apoptosis induction could be identified.

Temsirolimus inhibits cell growth in combination with inhibitors of the B-cell receptor pathway.

Lately, mTOR inhibitors have gained clinical relevance in malignant lymphoma. Still, rapamycin derivatives may activate a pro-survival feedback loop through PI3K-Akt. In this current study, temsirolimus effectively reduced cell growth in GCB and ABC diffuse large cell B-cell lymphoma (GCB=30-66%, ABC=45-57%). Combination treatment with the PI3K-δ inhibitor idelalisib additively effected ABC and GCB lymphoma (GCB=16-38%, ABC=25-50%). Since Bruton's Tyrosine Kinase (BTK) plays a significant role for the survival of ABC lymphoma, this study also combined the BTK inhibitor ibrutinib with temsirolimus, which resulted in additive cell growth reduction (ibrutinib 50%, temsirolimus 44%, combination 25%) in ABC lymphoma. In contrast, bortezomib, which has been shown previously to be efficient in ABC lymphoma, revealed an antagonistic effect with temsirolimus in some GCB lymphoma (temsirolimus 53%, temsirolimus+bortezomib 63%). Western blot analysis identified the increase of phosphorylated pro-survival kinases Akt and PDK as a possible underlying mechanism of this interaction.