ALBERT

Description: Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous category of lymphoid tumors that comprises different clinical forms not fully recognized in the WHO classification. In this regard, extranodal (EN) DLBCLs have particular clinicobiological features and outcome, sometimes related to the specific site where the lymphoma arises. Nowadays, rituximab plus chemotherapy (CT) is the gold-standard in the treatment of DLBCL. However, the superiority of rituximab-CT (R-CT) over CT alone has not been addressed for all the clinical subsets of the disease and, in fact, the clinical role of the new therapies might be different for primary nodal or EN DLBCLs. The aim of this study was to assess the impact of rituximab in patients suffering from nodal or EN DLBCL. Two-hundred and thirty non-immunocompromised patients (112M/118F; median age, 61 years) diagnosed with CD20+DLBCL in a single institution between 1997 and 2006 (five years before and after establishing R-CT as the standard treatment in DLBCL) and treated with adriamycin-containing regimens were the subject of the present study. The series included 148 primary nodal and 82 EN DLBCL. Patients with primary CNS lymphoma were excluded and lymphomas arising at Waldeyer ring were considered as nodal DLBCL. The main EN sites were GI (n=26), bone (n=13), soft tissue (n=13), lung/pleura (n=9), liver (n=9), and other (n=12). Main clinico-biological and evolutive variables were analyzed. One hundred nineteen patients received only CT and 111 R-CT. Eighty-seven cases with available information were assigned to germinal center B-cell-like (GCB) (41%) or non-GCB (59%) groups according to the Hans method (Blood2004;103:275–82) based on CD10, BCL6 and MUM1 expression. Main initial features, including the primary nodal or EN origin, international prognostic index (IPI), and GCB/non-GCB categories were similar for CT and R-CT groups. No correlation was observed between the GCB/non-GCB groups and the primary site of the tumor, although nodal lymphomas more frequently expressed MUM1 than EN (69% vs. 31%, respectively; p=0.01). CR rate and 5-year overall survival (OS) according to the treatment arm (CT vs. R-CT) is detailed for the whole series and for the nodal and EN groups in the table and OS curves depicted in the figure. In the whole series, variables predicting poor OS in the multivariate analysis were high-risk IPI (RR 2.5; p

Description: Diffuse large B-cell lymphomas (DLBCLs) can be divided into germinal-center B cell–like (GCB) and activated-B cell–like (ABC) subtypes by gene-expression profiling (GEP), with the latter showing a poorer outcome. Although this classification can be mimicked by different immunostaining algorithms, their reliability is the object of controversy. We constructed tissue microarrays with samples of 157 DLBCL patients homogeneously treated with immunochemotherapy to apply the following algorithms: Colomo (MUM1/IRF4, CD10, and BCL6 antigens), Hans (CD10, BCL6, and MUM1/IRF4), Muris (CD10 and MUM1/IRF4 plus BCL2), Choi (GCET1, MUM1/IRF4, CD10, FOXP1, and BCL6), and Tally (CD10, GCET1, MUM1/IRF4, FOXP1, and LMO2). GEP information was available in 62 cases. The proportion of misclassified cases by immunohistochemistry compared with GEP was higher when defining the GCB subset: 41%, 48%, 30%, 60%, and 40% for Colomo, Hans, Muris, Choi, and Tally, respectively. Whereas the GEP groups showed significantly different 5-year progression-free survival (76% vs 31% for GCB and activated DLBCL) and overall survival (80% vs 45%), none of the immunostaining algorithms was able to retain the prognostic impact of the groups (GCB vs non-GCB). In conclusion, stratification based on immunostaining algorithms should be used with caution in guiding therapy, even in clinical trials.

Description: Background Allogeneic stem-cell transplantation with myeloablative conditioning (MAC) in multiple myeloma (MM) is associated with a high transplant-related mortality (TRM) with a 15% of long-term survivors. Allogeneic transplantation with reduced-intensity conditioning (alloRIC) results in a lower TRM with a higher relapse rate. When used in first line in a tandem transplant approach (auto/alloRIC), the incidence of acute graft-versus host disease (aGvHD) grade II-IV reported ranges between 20-43%, chronic GvHD between 50-75% and the TRM between 10-15%. The reported PFS was 25% beyond 7 years. Because of this high morbimortality and the higher rate of relapse, the role of allogeneic transplantation in MM remains controversial, especially as part of the front-lline therapy. Aim to analyze the results of allogeneic transplantation in patients with MM outside clinical trials at our institution over a period of 27 years. Patients and Methods Between Feb 1986 and April 2009, 23 patients (17 M, 6 F, median age 41 –range 21-52 -) received a MAC from an HLA identical sibling donor. Disease status at the time of transplant was first response in 12 patients (53%) (3 CR, 9 PR), sensitive relapse in 3 (13%) (all PR) and refractory disease in 8 (35%). Conditioning regimen was heterogeneous (6 Cyclo/TBI, 2 Bu/Cyclo, 3 BCNU/Mel/Cyclo/TBI, 4 Cyclo/Mel/TBI, 5 Mel/TBI, 2 Bu/Mel). GvHD prophylaxis consisted on cyclosporine/MTX (10), cyclosporine/PDN (8), cyclosporine (2) or other (3). Between April 2001 and Aug 2012, 31 patients (18 M, 13F, median age 48 –range 25-64) received an alloRIC: 25 of them (80%) from an identical sibling donor and 6 (20%) from an unrelated donor. Seven patients (13%) who did not achieve a CR after front-line autologous transplant received an alloRIC in a tandem strategy. 17 (31%) were in sensitive relapse (first relapse 14, second relapse 3). Seven patients (13%) had refractory disease at the time of alloRIC. Conditioning regimen consisted on Fluda/Mel (26 patients), Flu/TBI (3) and Fluda/Mel/bortezomib (2). GVHD prophylaxis consisted on cyclosporine/MTX (6) or cyclosporine/MMF (25). All patients in the alloRIC group had received a prior single autologous transplant. Results On an intention-to-treat analysis, the CR rate after MAC was 35%. The incidence of aGvHD grade II-IV and III-IV were 48% and 39%, respectively. The TRM at any time was 56%. The causes of death were GvHD in 7 patients, infection not related to GvHD in 5 patients and VOD in 1 patient. The relapse rate was 30%.There are 3 patients who remain in continued CR at 13, 23 and 27 years beyond transplantation. With alloRIC the CR rate was 45%. The incidence of aGvHD grade II-IV and III-IV were 55% and 22%, respectively. Nine patients develop chronic GvHD. The TRM at any time was 29% and the causes of death were GVHD in 7 patients and pulmonary hemorrhage and postransplant lymphoma one patient each. Nine patients remain alive in continued CR from 5 months to 9 years of follow-up. After a median follow-up of 36.4 months, the median PFS was not significantly different between MAC and alloRIC and there was a trend towards a longer overall survival in the alloRIC group (4.6 vs 35 months, p=0.05). Conclusions Although a small fraction of patients with MM can be cured with MAC allogeneic transplantation, this procedure is associated with an extremely high TRM. Unfortunately, alloRIC was also associated with a high incidence of severe aGVHD resulting in a high TRM leading to a short PFS. New approaches aimed at decreasing the incidence of aGVHD are crucial. Disclosures: Jiménez: Janssen: Honoraria. Rosiñol:Janssen: Honoraria; Celgene: Honoraria. Blade:Janssen: Honoraria; Celgene: Honoraria.

Description: Background: Allogeneic hematopoietic stem cell transplantation (alloSCT) from unrelated donors mismatched (MMUD) at a single HLA-A, -B, -C, or -DRB1 locus (7/8) were previously reported to be associated with lower overall survival (OS) and disease-free survival (DFS), higher treatment-related mortality (TRM), and more acute graft-versus-host disease (GVHD) compared to 8/8 matched unrelated (MUD) allografts. Despite these risks, 7/8 MMUD grafts remain a viable option for alloSCT, particularly in patients who lack suitable donors or in those with aggressive hematologic malignancies for whom the risks of disease progression due to delays in identifying optimal donors is offset in part by the benefits of earlier transplantation with a 7/8 MMUD alloHCT. According to the published experience of post-transplant cyclophophamide (PTCy) in the context of haploidentical alloSCT, this GVHD prophylaxis strategy could potentialy overcome the detrimental effect of a single-locus HLA MMUD. Methods: We retrospectively analyzed 72 consecutive adult patients (median age 53y, range 18-69) who received 7/8 MMUD (n=44) or 8/8 MUD (N=28) alloSCT with PTCy in our institution. Unrelated donor selection was performed according to standard criteria, including high resolution typing for alleles at HLA-A, -B, -Cw, DRB1 and DQB1. For those patients in whom an 8/8 HLA-matched related or unrelated donor was not available, a search was performed based on a single HLA-mismatch. Results: Acute myeloid or lymphoblastic leukemia accounted for 51% of all hematologic diseases, myelodisplastic syndrome for 17%, chronic lymphoproliferative or myeloproliferative disorders for 28%, and severe aplastic anemia for 4%. Disease Risk Index (DRI) was intermediate in 51%, high 16% and very high 6%. Forty-four percent of patients had a HCT-CI ≥3. All patients, except 6 have received peripheral blood stem cells (PBSC). Fludarabine-based conditioning regimens were used in all patients (fludarabine-busulphan in 61%); of them, myeloablative (MAC) in 34 patients (47%) and RIC in 38 (53%). GVHD prophylaxis consisted on PTCy 50mg/kg IV on days 3 and 4 after transplant followed by one (tacrolimus or mycophenolate mofetil, MMF) (n=62, 86%) or 2 (n=10, 14%) immunossuppresor drugs. All but two patients engrafted and the median time to neutrophil (〉500/mL) and platelet (〉20,000/mL) recovery were 18 days (range 11-30) and 18 days (10-47), respectively. Thirteen patients (18%) developed an invasive pulmonary Aspergillosis, 20 (27%) had severe bacterial infection, 40 (56%) CMV reactivation, 5 (7%) cytomegalic disease and 3 EBV reactivation. The cumulative incidences of 1-year TRM, 100-days acute grade II-IV, 100-days grade III-IV GHVD, and 1-year moderate-severe chronic GHVD were 19%, 24%, 13%, and 11%, respectively. The cumulative incidence of relapse at 1-year was 16%. After a median follow-up for surviving patients of 12 months (2-60), 2-year OS, DFS, and survival free of moderate/severe chronic GVHD and relapse (cGRFS) were 64%, 61%, and 49%, respectively. Univariate analysis of variables that could influence OS, PFS, and cGRFS, including age, donor/patient sex, comorbidity, DRI, conditioning type, 1 vs. 2 immunosuppressors, and HLA 7/8 vs. 8/8 did not show any statistical differences. At 6 and 12 months after alloSCT, 42% and 73% of patients alive and without relapse were free of immunosuppressor drugs and prednisone. Conclusions: This study suggests that PTCy after unrelated PBSC alloSCT results in a low incidence of acute and chronic GVHD with encouraging survival outcomes even in the context of 7/8 HLA-mismatched transplant. An immunosuppressive schema of intermediate intensity such as PTCy followed by single-agent tacrolimus may provide an adequate GVHD prophylaxis and could be a good alternative to ATG in both MMUD and MUD transplants. Confirmatory and comparative studies are warranted to examine the effect of this approach on alloSCT outcomes. Disclosures Rosinol: Janssen, Celgene, Amgen, Takeda: Honoraria. Martinez:BMS: Research Funding; Takeda: Consultancy.

Description: Abstract 1770 Bronchial-associated lymphoid tissue (BALT) lymphoma is a distinct subgroup of low grade B-cell extranodal lymphoma. The limited clinical information available in the literature makes it difficult to understand if such an indolent lymphoma may have a clinical outcome different from that observed in other extranodal marginal zone lymphomas. The aim of this study is to collect and analyze clinical characteristics of patients with primary marginal zone malignant lymphoma of the lung principally focusing on diagnosis, treatment modality, outcome and finally to evaluate biological and molecular features which may correlate with clinical behaviour. We collected clinical information and histological material on 73 patients diagnosed with marginal zone lymphoma of the lung from February 1990 to August 2008. Central pathology reviewed all histopathological material and the diagnosis was confirmed in 64 (88%) patients. The retrospective analysis has been conducted on this subset of patients. The majority of them (58/64) had limited disease at diagnosis with a good performance status (0-1) and low prognostic index (IPI 0–2). FISH analysis showed a rearrangement on 18q21 in 12 of cases. Median time from diagnosis to any treatment was 30 days (range 0–773). Twenty patients received only local treatment including definitive surgery or radiotherapy. 52 patients needed additional systemic treatment because of advanced stage or incomplete surgical resection. Most of them (26) received an alkylating containing regimen while only 10 patients were treated with an anthracycline containing regimen and 16/52 received monoclonal antibody in combination with chemotherapy. With a median follow up of 54 months, 17/64 patients (27%) relapsed. The median time to relapse was 28 months (range 1–82). No difference in terms of PFS or OS was observed among patients receiving systemic anthracycline or alkylating containing regimens. No significant correlation with MALT 1 aberrations was found. Clinical results observed in such retrospective study seem to suggest as surgery clearly benefits patients with localized disease. Chemotherapy can be reserved for early aggressive relapse. Systemic treatment could be recommended for patients with advanced stage or with incomplete response after the surgical procedure: when chemotherapy must be considered, alkylating containing regimens seem the best option. Considering data of a “pre-rituximab era”, the role of monoclonal antibodies still needs to be clarified and ongoing trials from IELSG could be helpful on this topic. Disclosures: No relevant conflicts of interest to declare.

Description: INTRODUCTION: Allogeneic hematopoietic stem cell transplantation (alloSCT) is the only curative strategy for relapsed/refractory T cell lymphoma (T-NHL). In the past ten years, there have been several improvements in conditioning regimens and graft versus host disease prophylaxis (GVHD), which have contributed to lower transplant-related mortality (TRM). Also, selective and low toxicity therapies, might improve response quality in some T-NHL Recently, haploidentical stem cell transplantation (Haplo) with post-transplant cyclophosphamide is a new option for those patients who do not have an HLA-identical sibling or a suitable unrelated donor, but also it has shortened the time for urgent cases. METHODS: This study analyzes overall outcomes of 211 consecutive patients diagnosed with T-NHL who received an alloSCT from 1995 to 2018 in GELTAMO/GETH centers. Previous therapies (chemotherapies and autologous stem cell transplantation) and baseline diagnostic parameters were recorded. RESULTS The median age at alloSCT was 47 years (range, 17-69). (see table 1). Forty-nine (23%) had primary extranodal disease. Disease status pre alloSCT was available in 202 patientes: 54% were in complete response (CR), 30% in partial response (PR) and 16% with stable/progressive disease (PD). Since 2013 BV was used as a bridge therapy in ≥ 3rd line in 25 patients with CD30+ tumor expression, it was effective in 20 (CR 68% (n=17), PR 12% (n=3) PD 16% (n=4), not assessed in 1 case). The use of BV was not associated with a better response probability pre alloSCT compared with other regimens used after third line and it did not impact on post alloSCT outcomes. Reduced intensity conditioning (RIC) was the most frequent (76%, n=156). (see table 2) GVHD prophylaxis were Methotrexate + CsaA or Tacrolimus (n=72, 35,8%), sirolimus-tacrolimus (n=37; 18,4%), Cy-post based (n=44, 21,9%; used in Haplo setting n= 29). The median follow-up of all cohort was 22.5 months (range, 0-280). The two year overall survival (OS) and disease free survival (DFS) were 60% (CI95%, 53-67%) and 76.7% (CI95%, 69.3-82.5%) (Figure 1A) We observed a significant improvement in alloSCT outcomes since 2011 (OS

Description: Abstract 3654 Background: Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous entity, showing affected patients a highly variable outcome. The improvement in survival gained with the addition of rituximab to CHOP chemotherapy (R-CHOP) led to re-define the international prognostic index (IPI). The new index, known as revised IPI (R-IPI), showed to be simpler as it groups the patients in only 3 risk groups. However, the effect of prior rituximab-therapy upon the usefulness and significance of previously recognized prognostic factors on patients relapsed or refractory and receiving subsequent treatment with rituximab plus chemotherapy in DLBCL remains unexplored. Biological parameters, including expression of Bcl-6, Bcl-2, p53 and MUM-1 have been described as IPI-independent prognostic factors. Objectives: The objective of this study was to evaluate the benefit of the R-IPI to predict the outcome of DLBCL patients at the relapse time following a front line treatment with chemotherapy and rituximab. We also aimed to establish in this population the relationship between immunohistochemical expression of biological parameters and outcome. Patients and methods: this was a multicentric, observational, post-authorization and cross-sectional study (ClinicalTrials.gov identifier: NCT01369784). Inclusion criteria were: patients with age ≥ 18 years with DLBCL refractory/relapsed after first line treatment with rituximab, with or without transplantation. Patients must have finished a rescue treatment including rituximab. Written informed consent was obtained from participants. When the data of the biopsies at diagnosis and relapse were available, immunohistochemical results of bcl-2, bcl-6, p53 and MUM-1 were obtained. Results: 152 patients were included (146 evaluables) with a median age of 58 years. At LDBCG diagnosis 48% had 〉 1 extranodal localization (29% had bone marrow disease), and 30% had ECOG 2 or greater. Eighty-one percent presented stages III or IV and 72% had elevated LDH. Three percent had very good prognosis R-IPI, 69% good prognosis R-IPI and 27% poor prognosis R-IPI. Most patients received R-CHOP as first line therapy. Overall response rate was 79% (40% complete remission). Relapse was confirmed with biopsy and histological study in 55 patients. At relapse 31% presented 〉 1 extranodal localization, 30% ECOG 2–4, 64% stages III-IV and 72% elevated LDH. R-IPI prognostic groups distribution at relapse were as follows: 8% very good, 75% good and 27% poor. R-ESHAP and R-GEMOX were the two more used rescue therapies resulting in 60% overall response rate (31% complete remission). R-IPI at relapse was significantly associated (p 〈 0,05) with overall response rate following R-chemotherapy rescue therapy. None of the immunohistochemical parameters analized correlated with rescue therapy results. Conclusions: This is the largest reported series analizing R-IPI in DLBCL at relapse/refractory in patients receiving R-chemotherapy. In this series of patients R-IPI calculated at the relapse time was the only prognostic factor capable of predicting the overall response to the second line of treatment. Thus R-IPI prognostic score is a simple and useful predictor for outcome in DLBCL at relapse/refractory Disclosures: No relevant conflicts of interest to declare.

Description: Abstract 4134 Gene expression profile (GEP) allows to distinguish two groups with different origin in patients with diffuse large B-cell lymphoma (DLBCL): germinal-center (GC) and activated (ABC), with the latter having a significantly poorer outcome. However, GEP is a technique not available in current clinical practice. For this reason, attempts to reproduce GEP data by immunophenotyping algorithms have been made. The aim of this study was to apply the most popular algorithms in a series of patients with DLBCL homogeneously treated with immunochemotherapy, in order to assess the correlation with GEP data and their usefulness to predict response and outcome of the patients. One hundred fifty seven patients (80M/77F; median age 65 years) diagnosed with DLBCL in 5 institutions of the Grup per l'Estudi dels Limfomes de Catalunya I Balears (GELCAB) during a 5-year period, treated with Rituximab-containing regimens (in most cases, R-CHOP), in whom histological material to construct a tissue microarrays (TMA) was available, constituted the subjects of the present study. Four algorithms were applied: Colomo (Blood 2003, 101:78) using CD10, bcl-6 and MUM1/IRF4; Hans (Blood 2004, 103:275) using CD10, bcl-6 and MUM1/IRF4; Muris (J Pathol 2006, 208:714) using CD10 and MUM1/IRF4, and Choi (Clin Cancer Res 2009, 15:5494), using CD10, bcl-6, GCET1, FOXP1 and MUM1/IRF4. The thresholds used were those previously described. GEP studies were performed in 62 patients in whom fresh frozen material was available. Main clinical and evolutive data were recorded and analyzed. The proportion of positive cases for the different single antigens was as follows: CD10 26%, bcl-6 64%, GCET1 46%, FOXP1 78% and MUM1/IRF4 28%. The distribution of cases (GC vs. non-GC) according to the algorithms is detailed in the table. In 88 of 110 patients (80%) with all the antigens available, the patients were allocated in the same group (either GC or non-GC). When the immunochemistry was compared with GEP data, the sensitivity in the GC group was 59%, 52%, 70% and 40% for Colomo, Hans, Muris and Choi algorithms, respectively. The sensitivity in the non-GC group was 81%, 85%, 62% and 84%, respectively. On the other hand, the positive predictive value (PPV) in the GC group was 81%, 83%, 72% and 77%, respectively. In non-GC subset the PPV for the different algorithms was 59%, 55%, 72% and 52%, respectively. We observed a higher percentage of misclassified cases in the GC-phenotype subset than in the non-GC subgroup. None of the immunohistochemical algorithms showed a significant superiority as surrogate of GEP information among the others. The ability of GEP groups as well as of groups defined by the algorithms to predict complete response (CR) rate, progression-free survival (PFS) and overall survival (OS) of the patients is showed in the table. Thus, whereas the GEP groups showed significant prognostic value for CR rate, PFS and OS, none of the immunohistochemical algorithms were able to predict the outcome. In conclusion, in a homogeneous series of DLBCL patients treated with immunochemotherapy, the different immunohistochemical algorithms were not able to mimic the GEP information. The prognostic impact of the groups defined by immunohistochemistry (GC vs. non-GC) was particularly low. N (%) CR rate N (%) 5-year PFS (%) 5-year OS (%) Colomo algorithm GC 53 (44) 39 (74) 48 54 Non-GC 68 (56) 53 (78) 55 62 Hans algorithm GC 61 (41) 47 (77) 54 60 Non-GC 88 (59) 67 (76) 52 59 Muris algorithm GC 87 (57) 63 (72) 48 57 Non-GC 65 (43) 51 (78) 56 63 Choi algorithm GC 45 (33) 32 (71) 48 54 Non-GC 90 (67) 70 (78) 52 61 Gene expression profile 30 (58) 25 (83) 76* 80** GC Activated 22 (42) 17 (77) 31* 45** * p=0.005, ** p=0.03. Disclosures: No relevant conflicts of interest to declare.

Description: Abstract 667 Historically CLL has been considered a non-proliferative disease characterized by accumulation of leukemic cells. However, recent clinical and biological observations are questioning this concept. From the clinical standpoint, although some patients have lymphocyte counts stable during the course of the disease, others exhibit a short lymphocyte doubling time, suggesting the existence of a significant cell proliferation. Some specific anatomic locations (bone marrow (BM) and lymph nodes) seem to be more prone to proliferation than peripheral blood (PB). The amount of cell proliferation and its prognostic significance has not been properly analyzed. Against this background, gene expression profiling of proliferation genes and the amount of cell proliferation in different tissue compartments (BM and PB) were examined in patients with CLL. In isolated CD19/CD5+ tumoral cells from 20 paired PB and BM samples, expression of genes (n=93) involved in the initiation and development of the cell cycle was analyzed by low-density TaqMan® arrays. The amount of proliferative (Ki67 positive) CLL cells was measured by flow cytometry in 50 paired samples. In addition, coexpression of molecules associated with cellular activation (CD38, CD71, CD69), adhesion (CD49d), chemokine receptors (CXCR4, CXCR3, CCR7), interaction between T and B cells (CD86), signaling (ZAP-70), and Toll-like receptors (TLR9) was compared between Ki67+ and Ki67- CLL subpopulations. Finally, the degree of proliferation was correlated with the main clinical and biological characteristics. As assessed by gene expression profile, the great majority of genes involved in the initiation and development of cell cycle were more expressed in BM than in PB. Of note, Ki67+ CLL cells were significantly higher in BM than in PB (mean: 1.13% vs 0.88%; p= 0.004). This difference on Ki67+ expression between BM and PB was particularly significant (mean: 1.6% vs 1.1%; p=0.01) in patients who progressed of their disease at any particularly time (n=20), whereas it was not observed in patients with stable disease. Proliferating (Ki67+) CLL cells had significantly increased expression of ZAP-70 (mean fluorescence intensity (MFI): 162 vs 94, p

Description: Abstract 3677 Lymphoplasmacytic lymphoma (LPL) is a very heterogeneous disease from the clinical stand point, including the fact that Waldenström macroglobulinemia (WM) can be recognized in a significant proportion of LPL cases. Whether LPL with and without criteria for WM differ in the clinical features and outcome is not well known and is the aim of the present study. For this purpose, 50 patients (median age, 67 years (range, 19 to 91; 50% males) with a tissue biopsy diagnostic of LPL or a bone marrow infiltration by LPL were included in the present study. Main clinic-biological characteristics and outcome were recorded and analysed. Bone marrow infiltration and presence of a serum paraprotein were observed in 42 cases (89%) and 37 cases (86%), respectively. WM according to WHO criteria was identified in 26 patients (60%). Thirty-four patients received treatment for LPL (69%), including rituximab at any time in 74% of treated patients. The main clinical features of the series according to the WM/LPL or non-WM/LPL criteria are listed in the table. No relevant differences were identified when comparing WM cases with remaining LPL cases, except for those determined by their definition. Six patients eventually developed solid neoplasms with no differences between both groups. After a median follow-up of 35 months (range 0,3 to 209), 17 patients have died, including 10 patients by disease progression, 2 by secondary malignancies, 2 by heart failure, and 3 by unknown causes. The median survival of the whole series was 133 months (CI 95%: 40–226). Among the ten patients who died as a result of disease progression, two different patterns were observed. In six cases disease progression was characterized by general symptoms and lymph node growth, whereas the other 4 cases showed severe cytopenias unresponsive to treatment. These patterns were both observed indistinctly in WM and the non-WM/LPL cases. OS was similar in both groups of patients (median OS 133 vs. 216 months in WM and non-WM, respectively; p=NS). In conclusion, no major differences were observed in terms of initial features and outcome among LPL patients according to the definition of WM or non-WM/LPL.FeaturesAll patients (n=50)WM/LPL patients (n=26)Non-WM /LPL patients (n= 24)Age (median, yrs)676668Gender (male, %)25 (50%)12 (46%)13 (54%)Stage IV (%)46 (94%)26 (100%)20 (87%)Bone marrow infiltration44 (90%)26 (100%)*18 (78%)*Serum paraprotein37 (86%)26 (100%)*11 (65%)*IgM type30 (81%)26 (100%)*4 (36%)*M size (median, g/L)181815.3ECOG ≥ 2 (%)8 (18%)2 (9%)6 (29%)Enlarged lymph nodes17 (37%)8 (33%)9 (41%)Splenomegaly12 (26%)5 (20%)7 (33%)Bulky disease7 (15%)3 (12%)4 (18%)Hb (