Outcomes of younger patients with mantle-cell lymphoma experiencing late relapse (>24 months): the LATE-POD study.

Patients with mantle cell lymphoma (MCL) who experience first relapse/refractoriness can be categorized into early or late progression-of-disease (POD) groups, with a threshold of 24 months from the initial MCL diagnosis. Bruton tyrosine kinase inhibitors (BTKi) are established standard treatment at first relapse, but their effectiveness as compared to chemoimmunotherapy (CIT) in late-POD patients remains unknown. In this international, observational cohort study, we evaluated outcomes amongst patients at first, late-POD beyond 24 months. Patients treated upfront with BTKi were excluded. The primary objective was progression-free survival from time of second-line therapy (PFS-2) of BTKi versus CIT. After accrual, all patients were prospectively followed-up. Overall, 385 late-POD patients were included from 10 countries. Their median age was 59 (range:19-70) years and 77% were males. Median follow-up from time of first relapse was 53 months (range:12-144). Overall, 114 patients had second-line BTKi, while 271 had CIT, consisting of rituximab-bendamustine (R-B, n=101), R-B and cytarabine (R-BAC, n=70), or other regimens (mostly cyclophosphamide-hydroxydaunorubicin-vincristine-prednisone-CHOP- or platinum-based, n=100). The two groups were balanced for clinicopathological features, and median time to first relapse (48 months for both). Overall, BTKi was associated with significantly prolonged median PFS-2 than CIT [not reached-NR vs 26 months, respectively, P=.0003], and overall survival [NR and 56 months, respectively, P=.03]. Multivariate analyses showed that BTKi was associated with lower risk of death than R-B and other regimens (hazard ratio-HR, 0.41 for R-B, 0.46 for others), but similar to R-BAC. These results may establish BTKi as the preferable second-line approach in BTKi-naïve MCL patients.

Ibrutinib improves survival compared with chemotherapy in mantle cell lymphoma with central nervous system relapse.

Central nervous system (CNS) relapse of mantle cell lymphoma (MCL) is a rare phenomenon with dismal prognosis, where no standard therapy exists. Since the covalent Bruton tyrosine kinase (BTK) inhibitor ibrutinib is effective in relapsed/refractory MCL and penetrates the blood-brain barrier (BBB), on behalf of Fondazione Italiana Linfomi and European Mantle Cell Lymphoma Network we performed a multicenter retrospective international study to investigate the outcomes of patients treated with ibrutinib or chemoimmunotherapy. In this observational study, we recruited patients with MCL with CNS involvement at relapse who received CNS-directed therapy between 2000 and 2019. The primary objective was to compare the overall survival (OS) of patients treated with ibrutinib or BBB crossing chemotherapy. A propensity score based on a multivariable binary regression model was applied to balance treatment cohorts. Eighty-eight patients were included. The median age at study entry was 65 years (range, 39-87), 76% were males, and the median time from lymphoma diagnosis to CNS relapse was 16 months (range, 1-122). Patients were treated with ibrutinib (n = 29, ibrutinib cohort), BBB crossing chemotherapy (ie, high-dose methotrexate ± cytarabine; n = 29, BBB cohort), or miscellaneous treatments (n = 30, other therapy cohort). Both median OS (16.8 vs 4.4 months; P = .007) and median progression-free survival (PFS) (13.1 vs 3.0 months; P = .009) were superior in the ibrutinib cohort compared with the BBB cohort. Multivariable Cox regression model revealed that ibrutinib therapeutic choice was the strongest independent favorable predictive factor for both OS (hazard ratio [HR], 6.8; 95% confidence interval [CI], 2.2-21.3; P < .001) and PFS (HR, 4.6; 95% CI, 1.7-12.5; P = .002), followed by CNS progression of disease (POD) >24 months from first MCL diagnosis (HR for death, 2.4; 95% CI, 1.1-5.3; P = .026; HR for death or progression, 2.3; 95% CI, 1.1-4.6; P = .023). The addition of intrathecal (IT) chemotherapy to systemic CNS-directed therapy was not associated with superior OS (P = .502) as the morphological variant (classical vs others, P = .118). Ibrutinib was associated with superior survival compared with BBB-penetrating chemotherapy in patients with CNS relapse of MCL and should be considered as a therapeutic option.

Chemotherapy after PD-1 inhibitors in relapsed/refractory Hodgkin lymphoma: Outcomes and clonal evolution dynamics.

Checkpoint inhibitors (CPIs) are routinely employed in relapsed/refractory classical Hodgkin lymphoma. Nonetheless, persistent long-term responses are uncommon, and one-third of patients are refractory. Several reports have suggested that treatment with CPIs may re-sensitize patients to chemotherapy, however there is no consensus on the optimal chemotherapy regimen and subsequent consolidation strategy. In this retrospective study we analysed the response to rechallenge with chemotherapy after CPI failure. Furthermore, we exploratively characterized the clonal evolution profile of a small sample of patients (n = 5) by employing the CALDER approach. Among the 28 patients included in the study, 17 (71%) were primary refractory and 26 (92%) were refractory to the last chemotherapy prior to CPIs. Following rechallenge with chemotherapy, response was recorded in 23 (82%) patients experiencing complete remission and 3 (11%) patients experiencing partial remission. The tumour evolution of the patients inferred by CALDER seemingly occurred prior to the first cycle of therapy and was characterized either by linear or branching evolution patterns. Twenty-five patients proceeded to allogeneic stem cell transplantation. At a median follow-up of 21 months, median PFS and OS were not reached. In conclusion, patients who fail CPIs can be effectively rescued by salvage chemotherapy and bridged to allo-SCT/auto-SCT.

Quality of life of adult cancer survivors enrolled in Humanitas Research Hospital's survivorship care model.

INTRODUCTION: Clinicians should address the different health needs of cancer survivors (CS). We investigated concerns about physical/psychosocial symptoms and quality of life (QoL) of CS enrolled in our survivorship program. Our primary aim is to describe the CS population and their quality of life, considering both physical and psychosocial issues, with the intent to identify some possible association with the most frequently observed variables. METHODS: Adult patients, after ≥ 5 years from achieving complete hematologic or solid tumor remission, were included. The self-administered questionnaire used in the survey was based on the "Cancer Survivors Survey of Needs" (Mayo Clinic). RESULTS: We analyzed data from 191 CS. The median age was 63 years (53 years at diagnosis), and 70% of patients were females. A total of 93 patients (49%) reported a quality of life (QoL) score > 2. The most common psychosocial symptom concerns were fear of relapse (53%), genetic counseling (43%), living with uncertainty (35%), defining a new sense of normal (31%), and managing stress (28%). Females are more at risk to develop the following concerns compared with males: pain (40% vs 21%), sleep disturbance (54% vs 30%), weight gain (42% vs 21%), osteoporosis (41% vs 11%), body changes (45% vs 13%), hair or skincare issues (42% vs 16%), hot flashes (40% vs 11%), fear of recurrence (74% vs 54%), and living with a sense of uncertainty (53% vs 29%). Younger patients reported a higher score (> 2) for physical and psychological concerns compared with older patients. CONCLUSION: In this study, differences in physical and psychological symptoms/stressors among women and younger patients were identified. Female and younger patients appear to report physical and psychosocial concerns more frequently than other subgroups of patients. These observations should be validated and deepened in larger, prospective studies and considered during the long-term follow-up of these subgroups of patients.

Lymphomas associated with chronic hepatitis C virus infection: A prospective multicenter cohort study from the Rete Ematologica Lombarda (REL) clinical network.

Chronic hepatitis C virus (HCV) infection is related with an increased risk of non-Hodgkin lymphomas (NHL). In indolent subtypes, regression of NHL was reported after HCV eradication with antiviral therapy (AT). In 2008 in Lombardy, a region of Northern Italy, the "Rete Ematologica Lombarda" (REL, Hematology Network of Lombardy-Lymphoma Workgroup) started a prospective multicenter observational cohort study on NHL associated with HCV infection, named "Registro Lombardo dei Linfomi HCV-positivi" ("Lombardy Registry of HCV-associated non-Hodgkin lymphomas"). Two hundred fifty patients with a first diagnosis of NHL associated with HCV infection were enrolled; also in our cohort, diffuse large B cell lymphoma (DLBCL) and marginal zone lymphoma (MZL) are the two most frequent HCV-associated lymphomas. Two thirds of patients had HCV-positivity detection before NHL; overall, NHL was diagnosed after a median time of 11 years since HCV survey. Our data on eradication of HCV infection were collected prior the recent introduction of the direct-acting antivirals (DAAs) therapy. Sixteen patients with indolent NHL treated with interferon-based AT as first line anti-lymphoma therapy, because of the absence of criteria for an immediate conventional treatment for lymphoma, had an overall response rate of 90%. After a median follow-up of 7 years, the overall survival (OS) was significantly longer in indolent NHL treated with AT as first line (P = 0.048); this confirms a favorable outcome in this subset. Liver toxicity was an important adverse event after a conventional treatment in 20% of all patients, in particular among DLBCL, in which it is more frequent the coexistence of a more advanced liver disease. Overall, HCV infection should be consider as an important co-pathology in the treatment of lymphomas and an interdisciplinary approach should be always considered, in particular to evaluate the presence of fibrosis or necroinflammatory liver disease.

Prevalence and clinical significance of the MYD88 (L265P) somatic mutation in Waldenstrom's macroglobulinemia and related lymphoid neoplasms.

A study has shown that MYD88 (L265P) is a recurring somatic mutation in Waldenström's macroglobulinemia (WM). We developed an allele-specific polymerase chain reaction (PCR) for this mutation, and analyzed bone marrow or peripheral blood samples from 58 patients with WM, 77 with IgM monoclonal gammopathy of undetermined significance (IgM-MGUS), 84 with splenic marginal zone lymphoma (SMZL), and 52 with B-cell chronic lymphoproliferative disorders (B-CLPD). MYD88 (L265P) was detected in 58/58 (100%) patients with WM, 36/77 (47%) with IgM-MGUS, 5/84 (6%) with SMZL, and 3/52 (4%) with B-CLPD. Compared to IgM-MGUS patients with wild-type MYD88, those carrying MYD88 (L265P) showed significantly higher levels of IgM (P < .0001) and presented Bence-Jones proteinuria more frequently at diagnosis (P = .002). During follow-up, 9 patients with IgM-MGUS progressed to WM or to marginal zone lymphoma. Using a case-control approach, the risk of evolution of patients carrying MYD88 (L265P) was significantly higher than that of patients with wild-type MYD88 (odds ratio 4.7, 95% confidence interval 0.8 to 48.7, P = .047). These findings indicate that the allele-specific PCR we developed is a useful diagnostic tool for patients with WM or IgM-MGUS. In this latter condition, MYD88 (L265P) is associated with greater disease burden and higher risk of disease progression, and the mutation may therefore also represent a useful prognostic marker.

The NOTCH pathway is recurrently mutated in diffuse large B-cell lymphoma associated with hepatitis C virus infection.

Hepatitis C virus has been found to be associated with B-cell non-Hodgkin lymphomas, mostly marginal zone lymphomas and diffuse large B-cell lymphoma. Deregulation of signaling pathways involved in normal marginal zone development (NOTCH pathway, NF-κB, and BCR signaling) has been demonstrated in splenic marginal zone lymphoma. We studied mutations of NOTCH pathway signaling in 46 patients with hepatitis C virus-positive diffuse large B-cell lymphoma and in 64 patients with diffuse large B-cell lymphoma unrelated to HCV. NOTCH2 mutations were detected in 9 of 46 (20%) hepatitis C virus-positive patients, and NOTCH1 mutations in 2 of 46 (4%). By contrast, only one of 64 HCV-negative patients had a NOTCH1 or NOTCH2 mutation. The frequency of the NOTCH pathway lesions was significantly higher in hepatitis C virus-positive patients (P=0.002). The 5-year overall survival was 27% (95%CI: 5%-56%) for hepatitis C virus-positive diffuse large B-cell lymphoma patients carrying a NOTCH pathway mutation versus 62% (95%CI: 42%-77%) for those without these genetic lesions. By univariate analysis, age over 60 years, NOTCH2 mutation, and any mutation of the NOTCH pathway (NOTCH2, NOTCH1, SPEN) were associated with shorter overall survival. Mutation of the NOTCH pathway retained an independent significance (P=0.029). In conclusion, a subset of patients with hepatitis C virus-positive diffuse large B-cell lymphoma displays a molecular signature of splenic marginal zone and has a worse clinical outcome.

Autologous stem cell transplantation with in vivo purged progenitor cells shows long-term efficacy in relapsed/refractory follicular lymphoma.

High-dose chemotherapy with autologous stem cell transplantation (ASCT) has been shown effective in the control of relapsed/refractory follicular lymphoma. We evaluate the long-term outcome of patients with relapsed or refractory follicular lymphoma treated with ASCT with in vivo purged progenitors cells. We report the long-term results of a prospective multicenter phase 2 trial on 124 relapsed/refractory follicular lymphoma patients treated with a program of anthracycline-based debulking chemotherapy, immunochemotherapy, mobilization of in vivo purged PBSC followed by ASCT. Median age was 52 years; 14% of patients had grade 3A histology. Debulking chemotherapy produced CR in 16% and PR in 71%, while 13% of patients progressed. After rituximab, cyclophosphamide, vincristine, prednisone (R-COP), CR was obtained in 60% and PR in 35%; 118 patients successfully mobilized PBSC and 117 proceeded to ASCT. The harvest in all the 32 molecularly informative patients was bcl-2 negative. TRM was 0%. The 5-year PFS was 54% and the 5-year OS was 83%. After a median f-up of 6.7 years (range 1.5-13.6), 54% are still in CR. These data show that prolonged PFS is achievable in relapsed/refractory patients with high dose autologous transplantation of in vivo purged progenitor cells.

The BRAF V600E mutation in hairy cell leukemia and other mature B-cell neoplasms.

The somatically acquired V600E mutation of the BRAF gene has been recently described as a molecular marker of hairy cell leukemia (HCL). We developed an allele-specific PCR for this mutation and studied 62 patients with HCL, 1 with HCL variant, 91 with splenic marginal zone lymphoma, 29 with Waldenström macroglobulinemia, and 57 with B-cell chronic lymphoproliferative disorders. The BRAF V600E mutation was detected in all HCL cases and in only 2 of the remaining 178 patients. These 2 subjects had B-cell chronic lymphoproliferative disorders that did not fulfill the diagnostic criteria for HCL. Despite the positive PCR finding, the mutation could not be detected by Sanger sequencing in these 2 cases, suggesting that it was associated with a small subclone. We conclude that the BRAF V600E mutation is present in all patients with HCL and that, in combination with clinical and morphologic features, represents a reliable molecular marker for this condition.

Real-World Outcome of Treatment with Single-Agent Ibrutinib in Italian Patients with Chronic Lymphocytic Leukemia: Final Results of the EVIdeNCE Study.

Real-world data in clinical practice are needed to confirm the efficacy and safety that ibrutinib has demonstrated in clinical trials of patients with chronic lymphocytic leukemia (CLL). We described the real-world persistence rate, patterns of use, and clinical outcomes in 309 patients with CLL receiving single-agent ibrutinib in first line (1L, n = 118), 2L (n = 127) and ≥3L (n = 64) in the prospective, real-world, Italian EVIdeNCE study. After a median follow-up of 23.9 months, 29.8% of patients discontinued ibrutinib (1L: 24.6%, 2L: 29.9%, ≥3L: 39.1%), mainly owing to adverse events (AEs)/toxicity (14.2%). The most common AEs leading to discontinuation were infections (1L, ≥3L) and cardiac events (2L). The 2-year retention rate was 70.2% in the whole cohort (1L: 75.4%, 2L: 70.1%, ≥3L: 60.9%). The 2-year PFS and OS were, respectively, 85.4% and 91.7% in 1L, 80.0% and 86.2% in 2L, and 70.1% and 80.0% in ≥3L. Cardiovascular conditions did not impact patients' clinical outcomes. The most common AEs were infections (30.7%), bleeding (12.9%), fatigue (10.0%), and neutropenia (9.7%), while grade 3-4 atrial fibrillation occurred in 3.9% of patients. No new safety signals were detected. These results strongly support ibrutinib as a valuable treatment option for CLL.

Allogeneic stem cell transplantation in patients with mantle cell lymphoma: results from the MANTLE-FIRST study on behalf of Fondazione Italiana Linfomi.

The role of allogeneic stem cell transplantation (allo-SCT) in mantle cell lymphoma (MCL) is uncertain, even more in the era of bruton's tyrosine kinase inhibitors (BTKi) and chimeric antigen receptor T-cells. We retrospectively analyzed 55 patients who underwent allo-SCT for MCL relapsed or refractory (r/r) after rituximab and high-dose cytarabine within the MANTLE-FIRST project. With a median follow-up of 3.7 years, non-relapse mortality (NRM), progression-free survival, and overall survival were 23%, 53%, and 56%, respectively. NRM was significantly higher in the case of acute graft-versus-host disease, > 2 prior lines of therapy, age > 60 years. The outcome was similar for patients with early (≤24 months) and late progression of disease. The use of BTKi as a bridge to allo-SCT did not increase the toxicity and allowed a good control of disease. Our real-life experience confirms that allo-SCT still represents an option in MCL patients, especially if young and early-relapsed.

Outcomes in first relapsed-refractory younger patients with mantle cell lymphoma: results from the MANTLE-FIRST study.

Patients with mantle cell lymphoma (MCL) that fail induction treatment represent a difficult-to-treat population, where no standard therapy exists. We evaluated outcomes in patients with first relapsed-refractory (r/r) MCL after upfront high dose cytarabine including standard regimens. Overall survival (OS-2) and progression-free survival (PFS-2) were estimated from the time of salvage therapy. The previously described threshold of 24 months was used to define patients as early- or late-progressors (POD). Overall, 261 r/r MCL patients were included. Second-line regimens consisted of rituximab-bendamustine (R-B, 21%), R-B and cytarabine (R-BAC, 29%), ibrutinib (19%), and others (31%). The four groups were balanced in terms of clinicopathological features. Adjusting for age and early/late-POD, patients treated with R-BAC had significantly higher complete remission (63%) than comparators. Overall, Ibrutinib and R-BAC were associated with improved median PFS-2 [24 and 25 months, respectively], compared to R-B (13) or others (7). In patients with early-POD (n = 127), ibrutinib was associated with inferior risk of death than comparators (HR 2.41 for R-B, 2.17 for others, 2.78 for R-BAC). In patients with late-POD (n = 134), no significant differences were observed between ibrutinib and bendamustine-based treatments. Ibrutinib was associated with improved outcome in early-POD patients.

Assessment of bone marrow involvement in non-Hodgkin's lymphomas: comparison between histology and flow cytometry.

Bone marrow (BM) examination is essential in the staging of non-Hodgkin's lymphoma (NHL) patients. Few studies have compared BM histologic findings with results of flow cytometric (FC) analysis. We analyzed the incidence and patterns of histologic BM involvement in a series of 753 patients with NHL. For 498 patients, a concurrent FC analysis on BM was available. Histologic involvement was detected at diagnosis in 311/753 (41%) patients. By FC, BM involvement was clearly detected in 150/498 (30%). After excluding 12 cases with equivocal histology, concordance between the two methods was detected in 411 (85%) cases (27% BMB+/FC+; 58% BMB-/FC-), while discordance was present in 75 (15%) (P < 0.001): 58 cases (12%) were BMB+/FC- and 17 (3%) were BMB-/FC+. Discordance was more frequent in FL and in lymphoplasmacytic lymphoma (LPL). These data demonstrate that the two methods are comparable in qualitative assessment of BM involvement in NHL, with the exception of FL and LPL. In FL, diffuse large B-cell lymphoma (DLBCL) and LPL, FC underestimates the extent of infiltrate with respect to histology.

A First-in-human Study of Tenalisib (RP6530), a Dual PI3K δ/γ Inhibitor, in Patients With Relapsed/Refractory Hematologic Malignancies: Results From the European Study.

BACKGROUND: Tenalisib (RP6530) is a novel, highly specific, dual phosphoinositide-3 kinases (PI3K) δ/γ inhibitor with nano-molar potency. MATERIAL AND METHODS: This was a phase I, open-label, 3 + 3 dose escalation, maximum tolerated dose determination study to evaluate the safety, pharmacokinetics, and efficacy of tenalisib in patients with relapsed/refractory hematologic malignancies. Tenalisib was administered orally twice/thrice daily in 28-day cycles with starting dose of 25 mg twice daily. RESULTS: Thirty-five patients were enrolled across 11 dose levels. No dose limiting toxicity was reported at any of the dose levels. The most common treatment-emergent adverse events irrespective of causality were asthenia and cough in 15 (43%) patients and pyrexia in 13 (37%) patients. The most frequently reported related treatment-emergent adverse events were diarrhea, nausea, and vomiting. Related grade 3/4 adverse events were limited to events of hypertriglyceridemia, neutropenia, and diarrhea. Pharmacokinetics showed rapid absorption. Based on maximum plasma concentration and area under the plasma-concentration time curve, dose proportionality was observed up to 400 mg dose. Of 31 patients included in the efficacy analysis, complete response was seen in 2 (7%) patients and partial response in 4 (13%) patients, with an overall response rate of 19% and a disease-control rate of 61%. The median duration of response was 5.7 months. Responders demonstrated a marked downregulation of phospho-AKT on C1D8. CONCLUSION: Tenalisib demonstrated acceptable safety up to 1200 mg twice a day with no dose-limiting toxicities. Consistent clinical response was seen at doses 200 mg BID and above. Pharmacodynamics correlated well with clinical outcome. Further phase I/II studies are being undertaken to evaluate efficacy across different histologies.

Mantle Cell Lymphoma of Mucosa-Associated Lymphoid Tissue: A European Mantle Cell Lymphoma Network Study.

While classical nodal mantle cell lymphoma (cMCL) is often associated with involvement of multiple extranodal sites, isolated extranodal disease (ED) at the time of diagnosis is a rare event; data on the outcome of these forms are lacking. On behalf of the European MCL Network, we conducted a retrospective analysis on the clinical characteristics and outcomes of MCL presenting with isolated or predominant ED (MALT MCL). We collected data on 127 patients with MALT MCL diagnosed from 1998 to 2015: 78 patients (61%) were male with a median age of 65 years. The involved sites include: upper airways + Waldeyer ring (40; 32%), gastrointestinal tract (32; 25%), ocular adnexa (17; 13%), oral cavity and salivary glands (17; 13%) and others (13; 1%); 7 patients showed multiple extranodal sites. The median follow-up was 80 months (range: 6-182), 5-year progression-free survival (PFS) was 45% (95% CI: 35-54) and 5-year overall survival (OS) was 71% (95% CI: 62-79). In an explorative setting, we compared MALT MCL with a group of 128 cMCL patients: MALT MCL patients showed a significantly longer PFS and OS compared with nodal cMCL; with a median PFS of 4.5 years vs 2.8 years (p = 0.001) and median OS of 9.8 years vs 6.9 years (p = 0.018), respectively. Patients with MALT MCL at diagnosis showed a more favorable prognosis and indolent course than classical nodal type. This clinical variant of MCL should be acknowledged to avoid possible over-treatment.

Italian real life experience with ibrutinib: results of a large observational study on 77 relapsed/refractory mantle cell lymphoma.

Although sometimes presenting as an indolent lymphoma, mantle cell lymphoma (MCL) is an aggressive disease, hardly curable with standard chemo-immunotherapy. Current approaches have greatly improved patients' outcomes, nevertheless the disease is still characterized by high relapse rates. Before approval by EMA, Italian patients with relapsed/refractory MCL were granted ibrutinib early access through a Named Patient Program (NPP). An observational, retrospective, multicenter study was conducted. Seventy-seven heavily pretreated patients were enrolled. At the end of therapy there were 14 complete responses and 14 partial responses, leading to an overall response rate of 36.4%. At 40 months overall survival was 37.8% and progression free survival was 30%; disease free survival was 78.6% at 4 years: 11/14 patients are in continuous complete response with a median of 36 months of follow up. Hematological toxicities were manageable, and main extra-hematological toxicities were diarrhea (9.4%) and lung infections (9.0%). Overall, 4 (5.2%) atrial fibrillations and 3 (3.9%) hemorrhagic syndromes occurred. In conclusions, thrombocytopenia, diarrhea and lung infections are the relevant adverse events to be clinically focused on; regarding effectiveness, ibrutinib is confirmed to be a valid option for refractory/relapsed MCL also in a clinical setting mimicking the real world.

Distinctive clinical and histological features of Waldenström's macroglobulinemia and splenic marginal zone lymphoma.

We studied 122 patients with Waldenström's macroglobulinemia (WM) and 98 with splenic marginal zone lymphoma (SMZL); 29 SMZL patients (30%) had a serum MC (IgM in 17 patients). SMZL differed from WM for female prevalence, abdominal and superficial adenopathy, spleen and liver involvement, positive HCV. The median MC level was 2.0 g/dL in WM and 0.95 g/dL in SMZL (P<.001). On BM histology, SMZL was characterized by sinusoidal infiltration (70% of cases) and by a more frequent nodular pattern (P<.01) while WM had a higher incidence of interstitial BM localization. After a median follow-up of 5.3 years, median OS was not reached for SMZL and was 12 years for WM (P=.23; 14 years for asymptomatic WM, 8 years for symptomatic WM). In conclusion, despite similar outcomes of these 2 entities, SMZL appears as a disease with distinct clinical features and BM histology and a peculiar association with HCV infection.