ALBERT

Description: Mantle cell lymphoma (MCL) is a rare and aggressive subtype of non-Hodgkin Lymphoma. Although a typical presentation as an indolent lymphoma, without systemic symptoms and with a good performance status, the mantle cell lymphoma is an aggressive one, hardly curable with standard chemo-immunotherapy. Although current approaches to mantle cell lymphoma, including newer agents (such as bortezomib, lenalidomide, temsirolimus and ibrutinib) and autologous stem cell transplantation, have greatly improved the outcomes of affected patients, this disease is still characterized by high relapse rates, with most patients eventually dying of lymphoma progression. Before official approval by EMA, patients with relapsed/refractory mantle cell lymphoma with unsatisfied critical medical urgency were granted ibrutinib early access through a Named Patient Program in Italy (NPP, DM 8 May 2003). This observational, non-interventional, retrospective, multicenter study focuses on collecting information about the effectiveness and safety of ibrutinib as single-agent in patients who received at least one dose of ibrutinib under the NPP in the period between 29/Jul/2014 and 25/Jan/2015 in Italy. Data from patients treated with ibrutinib outside a controlled clinical trial within a NPP could give additional information about the clinical use, treatment duration, efficacy and toxicity of ibrutinib given to relapsed or refractory MCL patients in a real life context. Fifty-three heavily pretreated patients were enrolled. They had received a median of previous therapies of 3, comprising lenalidomide, bortezomib, temsirolimus and autologous stem transplant. Ninety-one percent had measurable disease and 83.0% had and ECOG performance status ≤2. At the end of therapy there were 11 complete responses (20.8%), 7 partial responses, 5 stable diseases and 30 progressions with an overall response rate of 33.9%. Twenty-six patients received ≥3 concomitant medications during ibrutinib therapy. At 20 months overall survival (OS) was 26.8% (median reached at 9 months) and disease free survival (DFS) 75% at 15 months: 10/11 patients are in continuous complete response with a median of 10.5 months. Hematological toxicities were manageable, 6 thrombocytopenia occurred, of which only 2 grade 4 (due to disease bone marrow infiltration) and the other 4 related to ibrutinib. Main extra-hematological toxicities were diarrhea (9.4%) and lung infections (7.5%) which all lead to early drug discontinuation. The observed occurrence of diarrhea by severity was 0 for CTCAE Grade 1, 4 for Grade 2, 2 for Grade 3 and 0 for Grade 4. Lung infection had a lower occurrence: 0, 2, 2 and 0 split by CTCAE Grade 1, 2, 3 and 4 respectively. There is a boundary zone in the passage from phase III to phase IV trials, i.e. from experimental to marketing and free use phases: in this zone we can find NPP and compassionate and off-label use. Despite the known potential bias of all the observational retrospective studies, reports on the real life experience make an important contribution to medical knowledge prior to widespread utilization: ibrutinib therapy is effective and tolerable also in a clinical setting mimicking the real world. Our results, in fact, are superimposable to those obtained in clinical trials: for safety, thrombocytopenia, diarrhea and lung infections are the relevant adverse events to be clinically focused on; for effectiveness, ibrutinib is confirmed to be a valid option for refractory/relapsed MCL. Disclosures Cascavilla: Janssen-Cilag: Honoraria. Zinzani:Abbvie: Membership on an entity's Board of Directors or advisory committees; Janssen: Membership on an entity's Board of Directors or advisory committees; MorphoSys: Membership on an entity's Board of Directors or advisory committees; Takeda: Membership on an entity's Board of Directors or advisory committees; Celegene: Membership on an entity's Board of Directors or advisory committees; Roche: Membership on an entity's Board of Directors or advisory committees.

Description: Introduction Fludarabine, cyclophosphamide and rituximab (FCR) and bendmaustine rituximab (BR) combinations have both been evaluated as salvage regimens in Waldenstrom's Macroglobulinemia. FCR exerts good quality of responses but there are some concerns regarding its use mainly for tardive myelosuppression and long term toxicity. BR showed to be effective with an excellent short term toxic profile but in literature there are no data on long term follow-up and toxicity. The aim of this study was to evaluate long term outcome and long term toxicity of patients treated with FCR and BR. Patients and Methods We analyzed 87 relapsed and refractory Waldenstrom's Macroglobuklinemia patients enrolled in two retrospective Italian multicenter studies in which FCR or BR were administered as salvage regimens. Patients treated with both bendamustine and fludarabine were excluded from the study. For each treatment group we compared: clinical and disease characteristics, Progression free survival (PFS) defined as progression or death for any cause from the beginning of salvage treatment; Event free survival (EFS) defined as progression or development of major infection, solid tumor, secondary MDS/AML, DLBCL, or death due to any cause. Results Of the 87 patients, 37 had received FCR and 50 BR. The two groups of patients did not differ in sex, median age, median number of prior treatments, previous therapy with alkylating agents, disease status, median IgM level, presence of adenopathies and/or splenomegaly at CT performed before salvage treatment. The significant differences between the two groups were: higher number of patients 〉70 years in the BR group (P=0.01) and lower number of patients previously treated with monoclonal antibody in the FCR population (P

Description: Background: The regression of hepatitis C virus (HCV)-associated lymphoma with antiviral treatment (AT) is the strongest argument in favour of an etiological link between lymphoma, especially marginal zone lymphoma (MZL), and HCV infection. In addition, the favourable impact of AT on overall survival of these patients has been reported (Arcaini 2014, Michot 2015). Although there is a clear association across the studies between the lymphoma regression and the clearance of HCV, the direct anti-lymphoma activity of interferon (IFN) cannot be ruled out. AT is undergoing a revolution: new antiviral drugs, including direct-acting antiviral (DAA) like sofosbuvir (SOF) cure more than 90% of infections. However, data on new IFN-free regimens in HCV-associated lymphoproliferative disorders are scanty and based on clinical reports (Rossotti 2015; Sultanik 2015; Carrier 2015). Patients and Methods: We analyzed virological and hematological response of 26 patients (pts) with indolent B-cell non-Hodgkin lymphomas (NHL) or chronic lymphocytic leukemia (CLL) and HCV infection treated with an IFN-free AT. We included the 5 cases reported in literature (Rossotti 2015; Sultanik 2015; Carrier 2015) with updated follow up. Results: Histological, virological and hematological features are summarized in Table 1. Histology distribution was as follows: 12 splenic MZL, 6 extranodal MZL of MALT, 2 leukemic MZL, 2 nodal MZL, 2 CLL/SLL, 1 lymphoplasmacytic lymphoma (LPL) and 1 low grade NHL NOS. Cryoglobulins were present in 13 (symptomatic cryoglobulinemia in 5). HCV genotype was 1 in 15 pts, 2 in 4 pts, 3 in 3 pts and 4 in 2 pts, NA in 2 pts. Three pts previously received chemotherapy and 4 underwent IFN-based therapy before. Twenty-four pts received a SOF-based regimens (SOF + simeprevir in 10, SOF + ribavirin in 5, SOF + daclatasvir in 8, SOF + ledipasvir in 1) and 2 pts other regimens (ombitasvir + paritaprevir + ritonavir + ribavirin and faldaprevir + deleobuvir + ribavirin). In one pt with renal MZL 4 rituximab (R) doses have been added to SOF + simeprevir. Median AT duration was 12 weeks (range: 6-24). At time of present analysis, virological response is available in 21 pts while hematological response has been assessed in 20 pts. A sustained virological response has been obtained in 20 pts; hematological response has been observed only in pts with HCV clearance: in particular 8 pts (all MZL) achieved a complete response and 4 (all MZL) a partial response (comprising one treated also with R) while 5 had stable disease (response by histology is summarized in Table 1). In 7 pts response duration is +1 mo (in 2 pts), +2 mo (in 1 pt), +6 mo (in 3 pts), and +22 mo (in 1 pt); 6 pts (60%) cleared cryoglobulins after AT. After a median follow-up of 6 mo (range: 1-28), 2 pts progressed: one pt shifted to DLBCL and one pt without virological response progressed and died of lymphoma; another pt with hematological CR died of metastatic hepatocellular carcinoma 8 mo after AT. Complete data for all pts will be presented at the meeting. Conclusions: Our study shows that a significant rate of hematological response can be achieved in HCV-associated MZL also with IFN-free AT. These data are a strong rationale for planning prospective trials with DAA in this setting. Table 1. Features of 26 pts with NHL associated with HCV infection treated with IFN-free regimen and lymphoma response by histology N % Age, median (range) 26 57 (40-78) M/F 11/15 42/58 - Marginal-zone lymphoma SplenicNodalExtranodal of MALTLeukemic MZL- CLL - Lymphoplasmacytic lymphoma - Low-grade B-cell NHL NOS 22 12 2 6 2 2 1 1 84.7 46.2 7.7 23.1 7.7 7.7 3.8 3.8 Ann Arbor stage III-IV 19 73 B symptoms 4 15 ECOG 0 1 2 3 11 10 0 1 50 45 0 5 BM involvement 14 54 Extranodal disease 17 65 Splenic involvement 13 50 Liver involvement 5 19 Nodal disease 15 58 Bulky disease 7 27 Leukemic disease 9 35 Elevated LDH 8/22 36 Elevated b2-microglobulin 8/10 80 Albumin

Description: Mantle cell lymphoma (MCL) is an uncommon type of non- Hodgkin lymphoma (NHL) comprising

Description: INTRODUCTION Treatment of Diffuse Large B cell lymphoma (DLBCL) in the elderly population is challenging as many patients (pts) are not eligible to receive standard curative therapy, due to comorbid conditions and to a higher susceptibility to the side effects of standard anthracycline containing regimens. Among currently available active drugs, Lenalidomide has been used in the setting of relapsed/refractory DLBCL both as monotherapy and in combination with rituximab, showing a good activity and an acceptable safety profile. We started a prospective, multicenter, single arm, phase II trial to demonstrate activity and safety of a chemofree combination of lenalidomide + rituximab in elderly (≥ 70 years) untreated pts with DLBCL who were prospectively defined as frail according to a simplified comprehensive geriatric assessment (sCGA) (Tucci A. et al., Leuk Lymphoma. 2015 Apr). PATIENTS AND METHODS Pts were eligible if they were previously untreated DLBCL patients, older than 69 years and defined as frail according to sCGA. The treatment consisted of a 28-day cycle (R2) combining oral Lenalidomide (20 mg on days 1 to 21) and i.v. Rituximab (375 mg/m2 on day 1); a maximum number of 6 cycles was planned; response assessment was performed after cycles 4 and 6. At the end of the 6thcycle, patients with partial or complete response continued treatment with Lenalidomide 10mg/d on days 1 to 21 every 28 days, until cycle 12or unacceptable toxicity. Final response was evaluated within 28 days after the last study drug administration. Primary study endpoint was Overall Response Rate (ORR) after 6 R2 cycles, defined according to Lugano 2014 criteria; co-primary endpoint was the rate of extra-hematological toxicity with CTCAE grade 〉2 and of death for any cause during the treatment The study was planned according to a two stage Simon design. A total of 68 pts had to be enrolled to complete the study: 23 pts were required in the first stage. Second stage could be activated withat least 12 patients showing a Partial or Complete Response (PR/CR) in stage I. According to the Ray and Rai method less than 15/23 adverse events were also required for the safety coprimary endpoint. RESULTS From January 2017 to December 2017, 24 newly diagnosed frail DLBCL were enrolled in 8 Italian centers. Median age was 83 years (range 76-89) and 79% had stage III/IV; 42% of pts were male, and 44%, had elevated LDH, 45% had High risk IPI (i.e. 3-5 risk factors). All pts were confirmed eligible and started R2 treatment. The planned 6 courses of R2 were completed in 13 pts (54%). The median number of R2 cycles was 6 (1-6). Treatment was discontinued in 11 pts for the following reasons: lymphoma progression in 4 cases, second malignancy in 2, extra-hematological toxicity in 3 cases, consent withdrawal and investigator choice after 4 cycles in CR in 1 case each. Response assessment after 6 R2 cycles showed12 responding pts (ORR 50%), 4 CR and 8 PR, that was higher than by the inferior limit required by the Simon optimal design. Regarding safety coprimary endpoint 13 events were reported including 9 extra-hematological toxicities 〉 grade 2 CTCAE (3 cardio-vascular and 6 respiratory events, all resolved) and 4 deaths (2 patients due visceral arterial ischemia and 2 due infectious disease). The rate of adverse events was lower than the superior limit of 15 allowed the first stage of the study.Since August 2018 the enrollment in the stage II of the trial has been resumed and it is currently ongoing with 45 patients enrolled. CONCLUSIONS The ReRi is the first study to evaluate activity and safety of a chemo-free therapy in patients with diffuse large B-Cell Lymphoma who are not eligible for conventional cytotoxic therapy. The results of the planned interim analysis of our study confirmed the initial efficacy and safety hypotheses of R2 combination in untreated elderly pts with DLBCL. Treatment of elderly frail DLBCL pts with R2 holds promise in terms of both ORR and safety. Disclosures Bassan: Amgen Inc.: Honoraria; Incyte: Honoraria; Pfizer: Honoraria; Shire: Honoraria. Merli:Sandoz: Membership on an entity's Board of Directors or advisory committees; Teva: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees, Other: Travel Expenses; Janssen: Honoraria; Takeda: Honoraria, Other: Travel Expenses; Gilead: Honoraria; Roche: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel expenses, Research Funding; Mundipharma: Honoraria. Liberati:AbbVie: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Clinical trial support; Roche: Other: Clinical trial support; Amgen: Membership on an entity's Board of Directors or advisory committees, Other: Clinical trial support; Celgene: Honoraria, Other: Clinical trial support; Bristol-Myers Squibb: Honoraria; Takeda: Membership on an entity's Board of Directors or advisory committees; Servier: Honoraria, Membership on an entity's Board of Directors or advisory committees; Incyte: Consultancy; Janssen: Honoraria; Novartis: Other: Clinical trial support. Luminari:ROCHE: Other: Role as Advisor ; CELGENE: Other: Role as Advisor & Travel Grant; TAKEDA: Other: Travel Grant; GILEAD: Other: Lecturer .

Description: Background: Marginal zone Lymphomas (MZL) are indolent B cell non hodgkin Lymphoma (NHL) and include splenic, nodal and extranodal subtypes (SMZL, NMZL, ENMZL). When therapy is needed in symptomatic patients, standard treatment usually requires systemic immunochemotherapy (ICT). Although the outcome of MZL is generally measured in decades a high heterogeneity of clinical behaviour exists that warrants the identification of accurate prognostic features to better estimate the risk of relapse, progression or death in the individual patient. Recently the analysis of progression free survival (PFS) was used to identify clinically useful endpoints in B-cell NHLs, with PFS at 24 (PFS24) months identified to stratify overall survival (OS) in follicular NHL. Here we examined the ability of PFS24 to predict subsequent OS in a large, multinational MZL cohort as part of the NF10 observational multicentric international study promoted by Fondazione Italiana Linfomi (FIL). Methods: The NF10 Project was started in 2010 as a prospective registry specifically conceived to investigate the prognosis of Indolent Non-Follicular B-Cell Lymphomas (INFL). The registration of clinical, laboratory data, treatment and outcome details of consecutive adult patients with newly diagnosed INFL was available at a dedicated website. All patients with a histologic confirmed diagnosis of INFL also including MZL were eligible with no exclusion criteria. Patients were followed based on local institution guidelines, and PFS was defined as time from the date of pathologic diagnosis to progression, re-treatment, or death due to any cause. PFS24 was calculated only for patients requiring immediate therapy and was defined as being alive and progression-free 24 months from diagnosis. Subsequent OS was defined as time from achieving PFS24 or time from progression in patients failing to achieve PFS24 (progression within 24 months of diagnosis). Results: Between July 2010 and July 2018, 1.253 INFL cases have been registered by 65 centres in Europe and South America. MZLs were 677 (54%): 283 ENMZL (43%), 221 SMZL (32%), 69 NMZL (10%); 104 cases were classified as disseminated MZL (Diss-MZL 15%) due to the lack of a clear pattern of organ involvement. Median age was 66 years (range 27-93); Ann Arbor stage was III-IV in 79%; 14% had B symptoms, 6% had ECOG performance status (PS) 〉1, lactate dehydrogenase (LDH) and β2-microglobulin were above upper normal limit (UNL) in 26% and 56% of cases respectively. Bone marrow involvement was present in 67%, positive HCV and HBV serology was found in 8% and 18% of cases respectively. For the current study we identified 400 patients with MZL for whom immediate therapy was planned right after lymphoma diagnosis. Patients with immediate therapy were 59% of all MZL. Rituximab (R) combined with chemotherapy was used in 332 (82%): R plus bendamustine (RB) in 142 (36%), R plus alkylating agents (R-alk) in 101 cases (25%) (mostly ENMZL), R plus CHOP in 50 (12%) (mainly NMZL and DissMZL); R monotherapy was used in 36 (9%). The median follow-up was 38 months (range 1-83). For treated pts 3y-PFS was 79% and 3y-OS was 90%; progressive disease was the cause of death in 47% of all cases. The percentage of patients who failed to achieve PFS24 was 20% with a lower frequency in the subtypes NMZL and ENMZL (13%) compared to the group of SMZL and DissMZL (24%, p=0.015). Three-year OS for patients with progression within the first 24 months was 46% (95%CI 28-63%) with a HR of 28.3 (95%CI 10.6 - 75.6) when compared with patients without early relapse (96%, 95%CI 91-98%). When PFS24 was adjusted by IPI in all cases and by HPLL (Montalbán et al, BJH 2012) in SMZL, the PFS24 retained its prognostic role (p

Description: Background: Almost all PCNSL belong to the category of DLBCL. However, affected pts are treated with high-dose methotrexate-based combinations that are not currently used in other DLBCL and require hospitalization and extensive expertise to manage toxicity. The use of R-CHOP could overcome these difficulties, but CNS availability of related drugs is poor. TNF induces BBB permeabilization and enhances CNS access of anticancer drugs. Coupling TNF with NGR, a peptide that targets CD13+ tumor vessels, improves its biological effects and therapeutic index. Thus, we tested the hypothesis that this conjugate (called NGR-hTNF) can break the BBB, thereby improving CNS access and activity of R-CHOP in pts with r/rPCNSL enrolled in a phase II trial (NCT03536039). Herein, we report results of activity, safety and BBB permeabilization. Methods: HIV-neg adults with PCNSL failed after methotrexate-based chemo and measurable disease were enrolled and treated with 1 course of R-CHOP, followed by 5 courses of R-CHOP21 preceded by NGR-hTNF (0.8 μg/m², 1-h inf). Overall response rate (ORR) was the primary endpoint. The two-stage Simon Minimax design was used; sample size estimated to demonstrate an improvement from 30% ORR (P0) to 50% (P1) (one-sided test; α 10%; β 90%) was 28 pts. NGR-hTNF/RCHOP would be declared active if ≥12 responses were recorded. As secondary endpoints, changes in vessel permeability, CD13 expression and anticancer drugs pharmacokinetics were assessed in the first 10 pts. Changes in BBB permeability were assessed by Dynamic Contrast Enhanced MRI (DCE-MRI) and 99mTc-DTPA-SPECT in tumor lesions, perilesional areas and normal appearing brain. DCE-MRI findings recorded before/after the 1st course (RCHOP alone - baseline) and before/after the 2nd and 6th courses (NGR-hTNF/RCHOP) were compared to establish the effect of TNF, and results were expressed as Ktrans values normalized using contralateral white matter. SPECT was performed before and after the 3rd course, and results were expressed as changes in the volume of ≥30% 99mTc-DTPA uptake (cm3). CD13 expression was assessed by immunohistochemistry on diagnostic tissue samples. Rituximab, cyclophosphamide and doxorubicin concentrations on matched CSF/plasma samples collected before/after the 1st, 2nd and 6th courses were tested to exclude a non-specific effect of NGR-hTNF on pharmacokinetics. Results: 22 pts (median age: 58 yo, range 26-78; 11 males) were enrolled; 18 pts had intermediate-high IELSG score. Pts were heavily pretreated: 13 had received ASCT, WBRT or both; 13 had refractory disease. Twenty pts were evaluable for the primary endpoint. NGR-hTNF/RCHOP combination was active: the predetermined activity threshold (≥12 responses) was achieved, with confirmed tumor response in 13 pts (65%; 95%CI= 45-85%), which was complete in 9. At a median follow-up of 8 months (2-26), 9 pts remain relapse free and 12 pts are alive. Treatment was well tolerated; toxicities were quickly solved without dose reductions or interruptions. G4 toxicities were neutropenia (49% of courses) and thrombocytopenia (15%), anemia (1%), and FN (1%). Ten SAEs were recorded in 8 pts: g2 seizures (n= 2), g2 DVT (2), g3 infections (2), g3 syncope (2), g4 FN and g2 LVEF reduction. There were 3 cases of g1-2 TNF infusion reaction. DCE-MRI studies showed an increase of vascular permeability after NGR-hTNF infusion as median (range) Ktrans of tumor and perilesional areas raised from baseline values of 23.5 (6.8-98.8) and 2.5 (0.4-3.9) to 35.3 (23.9-887.7; p= 0.39) and 4.7 (2.2-37.7; p= 0.01), respectively. Likewise, SPECT studies showed a significant enlargement of the volume ≥30% 99mTc-DTPA uptake, with median (range) values before and after NGR-hTNF infusion of 26 cm3 (5 - 67) and 40 cm3 (10 - 92), respectively (p= 0.02), with a median volume increase of 45% (14-87%). As important features supporting the specificity of the effect of NGR-hTNF, CD13 was expressed in all diagnostic samples, and drug levels in CSF/plasma samples were not influenced by NGR-hTNF. Conclusions: NGR-hTNF/RCHOP is active and safe in pts with r/rPCNSL. NGR-hTNF enhances vascular permeability specifically in tumor lesions and perilesional areas, which was consistently demonstrated by DCE-MRI, SPECT and plasma/CSF pharmacokinetics studies and was in line with CD13 expression. Accrual completion is warranted. This innovative approach deserves to be addressed as first-line treatment in PCNSL pts. Disclosures Angelucci: Novartis: Honoraria, Other: Chair Steering Comiittee TELESTO Protocol; Vertex Pharmaceuticals Incorporated (MA) and CRISPR CAS9 Therapeutics AG (CH): Other: Chair DMC; Jazz Pharmaceuticals Italy: Other: Local ( national) advisory board; Roche Italy: Other: Local (national) advisory board; Celgene: Honoraria, Other: Chair DMC.

Description: Key Points CD37 positivity predicts significantly better survival for DLBCL, and is superior to other prognostic factors in GCB-DLBCL. CD37 loss is an important risk factor for R-CHOP resistance in both GCB- and ABC-DLBCL.

Description: Introduction: Targeted RNA sequencing using Next Generation Sequencing (NGS) has significant advantages over transcriptome sequencing. In addition to information on mutations, fusion and alternative splicing, RNA quantification using targeted RNA sequencing is sensitive, reproducible and provides better dynamic range. We used targeted RNA sequencing for RNA profiling of diffuse large B-cell lymphoma (DLBCL) and explored its utility in the sub-classification of DLBC to ABC and GCB. Method: RNA extracted from 441 FFPE lymphnode samples with DLBC lymphoma and sequenced targeting 1408 genes. These cases were previously subclassified as ABC vs GCB using expression profiling and immunohistochemistry. We first normalized RNA expression data to PAX5 expression, then we tried to narrow down important markers using univariate significance tests. Setting the cutoff for false discovery rate at 0.0001, 48 variables remained significant, including 46 RNA levels and two genes (MYD88 and EZH2) mutation status. Using 60% of samples as training set, we used multiple statistical approaches for classification. Deep learning emerged as the best approach. We used autoencoder with 5 hidden layers and developed a model for classification of ABC vs GCB. To further improve on classification, we divided patients in each subgroup based on survival using simple tree model. In this tree model, expression level of CD58 emerged as a powerful prognostic marker for the ABC group and RLTPR expression in the GCB group. Results: Using probability of scoring developed based on deep learning and logestic regression, approximately 30% of the cases had a score between 0.5 and 0.75. For the remaining 70% of patients, the ABC vs GCB classification showed sensitivity and specificity of 96% and 97% for the testing set. We also applied the same approach to 60 independent cases classified using NanoString (Lymph2Cx). Our model showed sensitivity and specificity of 96% and 97% in the NanoString independent cases. Using the tree model for further classification of the ABC and GCB classes, CD58 mRNA levels separated the ABC group into two subgroups (ABC1 and ABC2) and RLTPR mRNA separated the GCB into two subgroups (GCB1 and GCB2) with significant difference in overall survival (P=0.0010) and progression-free survival (PFS) (P=0.0027). Conclusion: Targeted RNA sequencing is very reliable and practical for the subclassification of DLBCL and can provide clinical-grade reproducible test for prognostically subclassification of DLBCL. Figure Disclosures Albitar: Genomic Testing Ccoperative: Employment, Equity Ownership. De Dios:Genomic Testing Ccoperative: Employment. Tam:Takeda: Consultancy; Paragon Genomics: Consultancy. Hsi:Abbvie: Research Funding; Eli Lilly: Research Funding; Cleveland Clinic&Abbvie Biotherapeutics Inc: Patents & Royalties: US8,603,477 B2; Jazz: Consultancy. Ferreri:Roche: Research Funding; Celgene: Consultancy, Research Funding; Novartis: Consultancy; Kite: Consultancy. Piris:Millenium/Takeda: Membership on an entity's Board of Directors or advisory committees, Other: Lecture Fees, Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees; Gilead: Membership on an entity's Board of Directors or advisory committees, Research Funding; Jansen: Membership on an entity's Board of Directors or advisory committees, Other: Lecture Fees; Nanostring: Membership on an entity's Board of Directors or advisory committees; Kyowa Kirin: Membership on an entity's Board of Directors or advisory committees; Kura: Research Funding. Kantarjian:Ariad: Research Funding; Agios: Honoraria, Research Funding; Daiichi-Sankyo: Research Funding; Novartis: Research Funding; BMS: Research Funding; Takeda: Honoraria; Actinium: Honoraria, Membership on an entity's Board of Directors or advisory committees; AbbVie: Honoraria, Research Funding; Jazz Pharma: Research Funding; Cyclacel: Research Funding; Immunogen: Research Funding; Amgen: Honoraria, Research Funding; Pfizer: Honoraria, Research Funding; Astex: Research Funding.

Description: Introduction. The majority of SMZLs display an indolent course, however the disease is still incurable and a significant proportion of patients (~25-30%) experience poor outcomes surviving 5 years, and for whom tumor material collected before initiation of medical therapy was available. Mutation analysis was performed by CAPP-seq targeted deep next generation sequencing of tumor genomic DNA. A stringent bioinformatic pipeline was applied to suppress the background noise allowing to call variants with a sensitivity of 5x10-2 in FFPE derived DNA. Copy number variations (CNVs) were identified by using the sequencing reads-based GATK4-CNV algorithm. IGHV rearrangements were obtained by using LymphoTrack® IGH FR1 Assay Panel kit. Molecular clusters were identified by an iterative algorithm that maximizes genetic distinctiveness of subgroups by reassigning patients between clusters that are created a priori based on the co-occurrence of genetic lesions. Relative survival, defined as the ratio between actuarial survival observed in the SMZL cohort and expected survival of the general population matched to patients by geographical origin, sex, age and calendar year of diagnosis, was calculated using the Ederer II method. Results. The analysis included 303 patients with a SMZL diagnosis confirmed on spleen histology. The sample size allowed to identify 30% differences in survival for molecular subgroups comprising at least 5% of cases with a statistical power between 80-100%. Median follow-up was 9.2 years. At 10 years, 85% of patients were alive, consistent with the known indolent behavior of this lymphoma. Genes recurrently affected by non-synonymous somatic mutations in 〉10% of SMZL included KLF2 (24%), NOTCH2 (19%), KMT2D (15%), TNFAIP3 (13%), EP300 and TP53 (10%). Deletion 7q was documented in 25% of cases and IGHV1-2*04 usage in 32%. By cluster analysis, three major molecular subgroups were identified, each of them characterized by a NOTCH pathway mutated gene (Fig. 1A). The first cluster was defined by NOTCH2 and/or KLF2 mutations and was enriched in TNFAIP3 mutations and IGHV1-2*04 gene usage (Fig. 1A). The second cluster was defined by SPEN mutations, and was enriched in KMT2D and other epigenetic gene mutations (Fig. 1A). The third cluster was enriched in NOTCH1 mutations (Fig. 1A). By relative survival analysis, the NOTCH2/KLF2 cluster showed a lower survival compared to the matched general population, indicating a significant impact of the disease on patients' expected survival (Fig. 1B). Conclusions. The large sample size and inclusion of SMZL confirmed by spleen histopathology review allowed for precise estimation of the prevalence of KLF2 and NOTCH2 mutations in this lymphoma. Three molecular clusters were identified in SMZL, each of them containing a NOTCH pathway gene, supporting the relevance of NOTCH signaling in the pathogenesis of SMZL. Patients belonging to the NOTCH2/KLF2 cluster had a lower relative survival compared to the matched general population. Disclosures Traverse-Glehen: Astra Zeneca: Other: Travel; Takeda: Research Funding. Gomes da Silva:Roche: Other: Institution's payment for consultancy, Travelling support; BMS: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other: lecture fees; Celgene: Other: Travelling support; Janssen: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other: lecture fees, Institution's payment for consultancy, Travelling support; Abbvie: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other: lecture fees; Gilead Sciences: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other: lecture fees, Research Funding. Ladetto:Celgene: Honoraria; Jannsen: Honoraria; Acerta: Honoraria; Abbvie: Honoraria; Sandoz: Honoraria; Roche: Honoraria. Rambaldi:Pfizer: Consultancy; Novartis: Consultancy; Omeros: Consultancy; Italfarmaco: Consultancy; Amgen Inc.: Consultancy; Roche: Consultancy; Celgene: Consultancy. Vitolo:Takeda: Speakers Bureau; Sandoz: Speakers Bureau; Gilead: Speakers Bureau; Janssen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Roche: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau. Zinzani:MSD: Honoraria, Speakers Bureau; Gilead: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; SERVIER: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; TG Pharmaceuticals: Honoraria, Membership on an entity's Board of Directors or advisory committees; Bayer: Membership on an entity's Board of Directors or advisory committees; PFIZER: Honoraria, Membership on an entity's Board of Directors or advisory committees; Merck: Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen: Honoraria, Speakers Bureau; Bayer: Membership on an entity's Board of Directors or advisory committees; TG Pharmaceuticals: Honoraria, Membership on an entity's Board of Directors or advisory committees; BMS: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celltrion: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Takeda: Membership on an entity's Board of Directors or advisory committees; PFIZER: Honoraria, Membership on an entity's Board of Directors or advisory committees; Verastem: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Merck: Honoraria, Membership on an entity's Board of Directors or advisory committees; Roche: Honoraria, Membership on an entity's Board of Directors or advisory committees; Astra Zeneca: Speakers Bureau. Gaidano:Roche: Consultancy, Honoraria; Gilead: Consultancy, Honoraria; AbbVie: Consultancy, Honoraria; Morphosys: Honoraria; Amgen: Consultancy, Honoraria; Janssen: Consultancy, Honoraria. Salles:Servier: Honoraria; Abbvie: Honoraria; F. Hoffmann-La Roche Ltd: Consultancy, Honoraria, Research Funding; Novartis: Consultancy, Honoraria; Amgen: Honoraria; BMS: Honoraria, Other: Advisory Board; Celgene: Honoraria, Other: Advisory Board, Research Funding; Acerta: Honoraria; Janssen: Honoraria, Other: Advisory Board; Merck: Honoraria; Pfizer: Honoraria; Morphosys: Honoraria; Gilead: Honoraria, Other: Advisory Board; Epizyme: Honoraria; Servier: Honoraria, Other: Advisory Board; Takeda: Honoraria. Zucca:Celltrion: Consultancy; AstraZeneca: Consultancy.