Identification of Very Low-Risk Subgroups of Patients with Primary Mediastinal Large B-Cell Lymphoma Treated with R-CHOP.

BACKGROUND: R-CHOP can cure approximately 75% of patients with primary mediastinal large B-cell lymphoma (PMLBCL), but prognostic factors have not been sufficiently evaluated yet. R-da- EPOCH is potentially more effective but also more toxic than R-CHOP. Reliable prognostic classification is needed to guide treatment decisions. MATERIALS AND METHODS: We analyzed the impact of clinical prognostic factors on the outcome of 332 PMLBCL patients ≤65 years treated with R-CHOP ± radiotherapy in a multicenter setting in Greece and Cyprus. RESULTS: With a median follow-up of 69 months, 5-year freedom from progression (FFP) was 78% and 5-year lymphoma specific survival (LSS) was 89%. On multivariate analysis, extranodal involvement (E/IV) and lactate dehydrogenase (LDH) ≥2 times upper limit of normal (model A) were significantly associated with FFP; E/IV and bulky disease (model B) were associated with LSS. Both models performed better than the International Prognostic Index (IPI) and the age-adjusted IPI by Harrel's C rank parameter and Akaike information criterion. Both models A and B defined high-risk subgroups (13%-27% of patients [pts]) with approximately 19%-23% lymphoma-related mortality. They also defined subgroups composing approximately one-fourth or one-half of the patients, with 11% risk of failure and only 1% or 4% 5-year lymphoma-related mortality. CONCLUSION: The combination of E/IV with either bulky disease or LDH ≥2 times upper limit of normal defined high-risk but not very-high-risk subgroups. More importantly, their absence defined subgroups comprising approximately one-fourth or one-half of the pts, with 11% risk of failure and minimal lymphoma-related mortality, who may not need more intensive treatment such as R-da-EPOCH. IMPLICATIONS FOR PRACTICE: By analyzing the impact of baseline clinical characteristics on outcomes of a large cohort of patients with primary mediastinal large B-cell lymphoma homogeneously treated with R-CHOP with or without radiotherapy, we developed novel prognostic indices which can aid in deciding which patients can be adequately treated with R-CHOP and do not need more intensive regimens such as R-da-EPOCH. The new indices consist of objectively determined characteristics (extranodal disease or stage IV, bulky disease, and markedly elevated serum lactate dehydrogenase), which are readily available from standard initial staging procedures and offer better discrimination compared with established risk scores (International Prognostic Index [IPI] and age-adjusted IPI).

Real-life experience with the combination of polatuzumab vedotin, rituximab, and bendamustine in aggressive B-cell lymphomas.

Transplant-ineligible relapsed/refractory (rr) diffuse large B-cell lymphoma (DLBCL) patients represent an unmet medical need. Polatuzumab vedotin (Pola), an anti-CD79b antibody-drug-conjugate (ADG), with bendamustine- rituximab(BR) has recently gained approval for these patients, both in the USA and Europe, based on the GO29365 phase IIb trial. Real-life data with Pola are extremely limited. We report the outcomes of 61 Greek patients, who received Pola-(B)R mainly within a compassionate use program. Treatment was given for up to six 21-day cycles. Bendamustine was omitted in three cases due to previous short-lived responses. Fourty-nine rrDLBCL(efficacy cohort-EC) and 58 rr aggressive B-NHL (safety cohort-SC) patients received at least 1 Pola-BR cycle. Twenty-one (43%) patients of the EC responded with 12/49 (25%) CR and 9/49 (18%) PR as best response. Median progression-free survival, overall survival and duration of response were 4.0, 8.5, and 8.5 months respectively, while 55% of patients experienced a grade ≥3 adverse event, mainly hematologic. Treatment discontinuations and death during treatment were mainly due to disease progression. Twenty-two (41%) patients received further treatment; 11/22 are still alive, including one after CAR-T cells, and two after stem cell transplantation. Our data confirm that Pola-BR is a promising treatment for rrDLBCL patients, inducing an adequate response rate with acceptable toxicity. Pola-BR could be used as bridging therapy before further consolidative treatments.

Positron emission tomography after response to rituximab-CHOP in primary mediastinal large B-cell lymphoma: impact on outcomes and radiotherapy strategies.

End-of-treatment (EoT) PET/CT is used as a guide to omit radiotherapy (RT) patients with primary mediastinal large B-cell lymphoma (PMBCL). We present the mature and extended results of a retrospective study evaluating the prognostic significance of EoT-PET/CT after adequate response to R-CHOP. Among 231 consecutive PMLBCL patients, 182 underwent EoT-PET/CT and were evaluated according to the Deauville 5-point scale (D5PS) criteria. Freedom from progression (FFP) was measured from the time of PET/CT examination. Among 182 patients, 72 (40%) had D5PS score 1 (D5PSS-1), 33 (18%) had 2, 28 (15%) had 3, 29 (16%) had 4, and 20 (11%) had 5. The 5-year FFP was 97, 94, 92, 82, and 44% for D5PSS-1, D5PSS-2, D5PSS-3, D5PSS-4, and D5PSS-5, respectively. Among 105 patients with unequivocally negative PET/CT (D5PSS-1/D5PSS-2), 49 (47%) received RT (median dose 3420 cGy) and 56 (53%) did not with relapses in 0/49 vs. 4/56 patients (2 mediastinum and 2 isolated CNS relapses).The 5-year FFP for those who received RT or not was 100% versus 96%, when isolated CNS relapses were censored (p = 0.159). Among D5PSS-3 patients (27/28 irradiated-median dose 3600 cGy), the 5-year FFP was 92%. The 5-year FFP for D5PSS-4 and D5PSS-5 was 82 and 44%; 44/49 patients received RT (median dose 4000 and 4400 cGy for D5PSS-4 and D5PSS-5). Our study supports the omission of RT in a sizeable fraction of PET/CT-negative patients and definitely discourages salvage chemotherapy and ASCT in patients with PMLBCL who conventionally respond to R-CHOP, solely based on PET/CT positivity in the absence of documented progressive or multifocal disease. The persistence of positive PET/CT with D5PSS < 5 after consolidative RT should not trigger the initiation of further salvage chemotherapy in the absence of conventionally defined PD.

Study of bone metabolism and angiogenesis in patients undergoing high-dose chemotherapy/autologous hematopoietic stem cell transplantation.

OBJECTIVES: As the interaction between hematopoietic stem cells (HSCs) and endosteal and endothelial niches in HSCs homing is essential, we aimed to study bone turnover and angiogenesis in 29 patients with lymphoma/multiple myeloma undergoing hematopoietic stem cell transplantation (HSCT). METHODS: Serum samples were collected before high-dose chemotherapy (HDT), at the end of HDT, after HSC infusion, at the nadir of myelotoxicity, and at engraftment. Bone metabolism (CTX, TRACP-5b, bALP, OC, DKK1, RANKL, OPG), and angiogenesis (Ang1, Ang2) markers were measured. These markers were also measured in 21 control patients before and after conventional chemotherapy. RESULTS AND CONCLUSIONS: Bone resorption declined during HSCT (decrease in TRACP-5b [P < .001] and CTX [P = .006]). Bone formation declined as well (decrease in bALP and OC [P < .001 for both]). RANKL/OPG ratio, an indicator of osteoclastic activation, did not change significantly (P = .5). Ang1/Ang2 ratio, a vessel equilibrium marker, decreased significantly (P < .001) suggesting endothelial destabilization. The changes observed in the control group were similar except of bALP and RANKL/OPG ratio. Moreover, Ang1/Ang2 ratio on the day after HSC infusion strongly correlated with time to neutrophil and platelet engraftment (P < .001 for both). Conclusively, bone turnover and vessel destabilization represent important events during HSCT probably reflecting the effect of chemotherapy.

Bone metabolism markers and angiogenic cytokines as regulators of human hematopoietic stem cell mobilization.

Hematopoietic stem cell (HSC) mobilization involves cleavage of ligands between HSC and niche components. However, there are scarce data regarding the role of bone cells in human HSC mobilization. We studied biochemical markers of bone metabolism and angiogenic cytokines during HSC mobilization in 46 patients' sera with lymphoma and multiple myeloma, by ELISA. Significant changes between pre-mobilization and collection samples were found: (1) Bone alkaline phosphatase (BALP) increased, indicating augmentation of bone formation; (2) Receptor activator of Nf-κB ligand/osteoprotegerin ratio (RANKL/OPG) increased, showing osteoclastic differentiation and survival; however, there was no evidence of increased osteoclastic activity; and (3) Angiopoietin-1/Angiopoietin-2 ratio (ANGP-1/ANGP-2) decreased, consistent with vessel destabilization. Poor mobilizers had significantly higher carboxy-terminal telopeptide of collagen type I (CTX) and lower ANGP-1 at pre-mobilization samples, compared to good ones. CTX, amino-terminal telopeptide of collagen type I (NTX) and ANGP-1 pre-mobilization levels correlated significantly with circulating CD34+ peak cell counts. Our results indicate that bone formation and vessel destabilization are the two major events during human HSC mobilization. Osteoblasts seem to be the orchestrating cells, while osteoclasts are stimulated but not fully active. Moreover, ANGP-1, CTX and NTX may serve as predictors of poor mobilization.

Detection of L265P MYD-88 mutation in a series of clonal B-cell lymphocytosis of marginal zone origin (CBL-MZ).

Clonal B-cell lymphocytosis of marginal zone origin (CBL-MZ) is a recently described entity characterized by the presence of clonal B cells in the blood and/or bone marrow (BM) with morphologic and immunophenotypic features consistent with marginal zone derivation in otherwise healthy individuals. CBL-MZ is commonly associated with paraproteinemia, usually immunoglobulin M (IgM), raising diagnostic difficulties from Waldenstrom macroglobulinemia (WM). The aim of the present study was to determine the presence of MYD-88 L265P mutation in a well-characterized series of CBL-MZ to identify cases that may in fact represent WM. Fifty-three CBL-MZ cases were retrospectively evaluated. MYD-88 L265P mutation was determined by allele-specific polymerase chain reaction in blood and/or BM mononuclear cells. Almost half of the CBL-MZ cases (49%) were associated with paraproteinemia mainly of the IgM type (65%). MYD-88 L265P mutation was identified in 10 cases (19%). These cases may truly represent WM, whereas 43 cases (81%) are still classified as CBL-MZ. Mutated cases were all associated with paraproteinemia compared with 37% of the nonmutated ones (P < .0001). In addition, mutated cases displayed more frequently CD38 and CD25 positivity (P = .002 and P = .005, respectively). Moreover, cases without paraproteinemia presented more frequently with lymphocytosis, irrespective of the presence of the MYD-88 mutation (P = .02). The present study demonstrates that MYD-88 L265P mutation may represent the only sensitive marker for the differentiation of CBL-MZ from probable WM. However, further studies are warranted to better define the biological significance of MYD-88 L265P mutation and to clarify whether the presence of the mutation establishes WM diagnosis or that it can also be present in borderline cases associated with paraproteinemia.

Prognostic Implication of the Absolute Lymphocyte to Absolute Monocyte Count Ratio in Patients With Classical Hodgkin Lymphoma Treated With Doxorubicin, Bleomycin, Vinblastine, and Dacarbazine or Equivalent Regimens.

Low absolute lymphocyte count (ALC) to absolute monocyte count (AMC) ratio (ALC/AMC) is an independent prognostic factor in Hodgkin lymphoma (HL), but different cutoffs (1.1, 1.5, and 2.9) have been applied. We aimed to validate the prognostic significance of ALC/AMC in 537 homogenously treated (doxorubicin, bleomycin, vinblastine, and dacarbazine or equivalents ± radiotherapy) classical HL patients at various cutoffs. The median ALC/AMC was 2.24 (0.44-20.50). The median AMC was 0.653 × 10(9)/L (0.050-2.070). Lower ALC/AMC was associated with established markers of adverse prognosis. In total, 477 (89%), 418 (78%), and 189 (35%) patients had an ALC/AMC ratio of ≥1.1, ≥1.5, and ≥2.9; respectively; 20% had monocytosis (≥0.9 × 10(9)/L). Ten-year time to progression (TTP) was 77% versus 55% for patients with ALC/AMC ≥1.1 and <1.1 (p = .0002), 76% versus 68% for ALC/AMC ≥1.5 and <1.5 (p = .049), 77% versus 73% for ALC/AMC ≥2.9 and <2.9 (p = .35), and 79% versus 70% for ALC/AMC ≥2.24 and <2.24 (p = .08), respectively. In stages ΙΑ/ΙΙΑ and in patients ≥60 years old, ALC/AMC had no significant effect on TTP. In advanced stages, ALC/AMC was significant only at the cutoff of 1.1 (10-year TTP 67% vs. 48%; p = .016). In younger, advanced-stage patients, the differences were more pronounced. In multivariate analysis of TTP, ALC/AMC < 1.1 (p = .007) and stage IV (p < .001) were independent prognostic factors; ALC/AMC was independent of International Prognostic Score in another model. ALC/AMC was more predictive of overall survival than TTP. At the cutoff of 1.1, ALC/AMC had independent prognostic value in multivariate analysis. However, the prognostically inferior group comprised only 11% of patients. Further research is needed prior to the widespread use of this promising marker.

Real-life Experience With Rituximab-CHOP Every 21 or 14 Days in Primary Mediastinal Large B-cell Lymphoma.

BACKGROUND/AIM: Primary mediastinal large B-cell lymphoma (PMLBCL) is an aggressive B-cell non-Hodgkin lymphoma (NHL), whose prognosis has greatly improved since the incorporation of the anti-CD20 monoclonal antibody rituximab into current therapeutic regimens. Evidence, however, on the optimal time interval between consecutive chemoimmunotherapy (CIT) cycles is still scarce. This study aimed to evaluate the efficacy outcomes of the more commonly administered 3-weekly regimens to the biweekly ones in a PMLBCL patients' population, who were mostly treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone every 21 days (R-CHOP-21) or R-CHOP-14. PATIENTS AND METHODS: We retrospectively studied our cohort of consecutively treated PMLBCL patients, focusing on their treatment density, in order to determine possible differences in treatment outcomes. RESULTS: CIT, in the form of both R-CHOP-21 as well as R-CHOP-14 (or similar regimens), is highly active in PMLBCL, with low rates of early treatment failure. In our cohort of patients, R-CHOP-14 did not result in a meaningful improvement of freedom from progression (FFP) or overall survival (OS). CONCLUSION: Both R-CHOP-14 and R-CHOP-21 are probably equally effective in PMLBCL, yet further, prospective, randomized studies are warranted to clarify whether dose-dense regimens can be associated with better disease control and long-term results.

Small Lymphocytic Lymphoma: Analysis of Two Cohorts Including Patients in Clinical Trials of the German Chronic Lymphocytic Leukemia Study Group (GCLLSG) or in "Real-Life" Outside of Clinical Trials.

BACKGROUND: Only few studies have focused exclusively on patients with small lymphocytic lymphoma (SLL). PATIENTS AND METHODS: In the present report, 103 SLL patients were analyzed from both, clinical trials of the German Chronic Lymphocytic Leukemia Study Group and Greek centers, and emphasis was placed on the therapeutic strategy. The impact of lymph node characteristics, such as the presence of proliferation centers (PCs) on response and survival was also assessed. RESULTS: SLL patients included in clinical trials were treated mostly with fludarabine-based regimens while those in "real-life" were staged and treated mostly as patients with low-grade lymphomas. Our analysis showed a trend for better survival for patients with SLL without detectable PCs. CONCLUSION: Patients with SLL outside of clinical trials are usually treated as cases of lymphoma. In addition, this analysis supports published data regarding the adverse prognostic value of the presence of PCs in lymphoid nodes in SLL.

Hodgkin Lymphoma Transformation of Chronic Lymphocytic Leukemia Under Ibrutinib Therapy: Chance Association or Therapy-related?

The established treatment algorithms for chronic lymphocytic leukemia (CLL)/small lymphocytic lymphoma (SLL) are currently challenged by novel classes of drugs, with ibrutinib being one of the most effective. Published data suggest that patients with early progression under ibrutinib often emerge as having Richter's transformation (RT) with a rapidly fatal prognosis, mostly developing diffuse large B-cell lymphoma (DLBCL). In this respect, it is known that RT to large DLBCL occurs in about 5% of patients with CLL during the disease course and less frequently to Hodgkin lymphoma (HL). Here, we report a patient with CLL who presented with HL transformation while still receiving therapy with ibrutinib stressing the need for clinical vigilance in any case with persisting or enlarging lymph nodes during treatment with this agent, as prompt modification of therapy is most important.

The Significance of PET/CT in the Initial Staging of Hodgkin Lymphoma: Experience Outside Clinical Trials.

AIM: To examine the real-life impact of baseline positron-emission tomography/computed tomography (PET/CT) in Hodgkin lymphoma (HL). PATIENTS AND METHODS: A total of 162 consecutive patients with HL were retrospectively studied. RESULTS: Disease was up-staged in 26 patients (16%) and down-staged in 9 (6%). However, treatment strategy was modified in only 10 patients (6% of total). Involved field radiotherapy was delineated according to PET/CT in 36/66 patients (59%). These treatment modifications did not significantly affect outcome. Moreover, three potent prognostic parameters were identified: the number of involved sites, maximum standardized uptake value (SUVmax), and the product of SUVmax and maximal largest lesion diameter, as a surrogate of total lesion glycolysis. All three significantly correlated with 5-year freedom from disease progression p=0.004, p=0.009 and p=0.04, respectively). CONCLUSION: Baseline PET/CT findings may lead to treatment modification in <15% of patients with HL without a significant impact on outcome. Certain PET/CT parameters have potent prognostic significance.

New insights in the mobilization of hematopoietic stem cells in lymphoma and multiple myeloma patients.

Following chemotherapy and/or the administration of growth factors, such as granulocyte-colony stimulated factor (G-CSF), hematopoietic stem cells (HSC) mobilize from bone marrow to peripheral blood. This review aims to systematically present the structure of the HSC "niche" and elucidate the mechanisms of their mobilization. However, this field is constantly evolving and new pathways and molecules have been shown to contribute to the mobilization process. Understanding the importance and the possible primary pathophysiologic role of each pathway is rather difficult, since they share various overlapping components. The primary initiating event for the mobilization of HSC is chemotherapy-induced endogenous G-CSF production or exogenous G-CSF administration. G-CSF induces proliferation and expansion of the myelomonocytic series, which leads to proteolytic enzyme activation. These enzymes result in disruption of various receptor-ligand bonds, which leads to the disanchorage of HSC from the bone marrow stroma. In everyday clinical practice, CXC chemokine receptor-4 (CXCR4) antagonists are now being used as mobilization agents in order to improve HSC collection. Furthermore, based on the proposed mechanisms of HSC mobilization, novel mobilizing agents have been developed and are currently evaluated in preclinical and clinical studies.

Clinical aspects of malt lymphomas.

Extranodal marginal zone lymphoma of the mucosa-associated lymphoid tissue (MALT) is an indolent lymphoma arising in extranodal sites. Several infectious agents and autoimmune disorders have been implicated in its pathogenesis. The stomach represents the most common and best-studied organ involved by MALT lymphoma and its development is strongly associated with Helicobacter pylori (Hp) infection. MALT lymphomas are characterized by an indolent clinical course and excellent survival in most cases, independently of the treatment delivered. Recent progress in the knowledge of the etiology and the cellular and molecular pathological events related to MALT lymphomas allowed us to improve our clinical understanding of this disease entity and to better define treatment strategies.

New insights into monoclonal B-cell lymphocytosis.

Monoclonal B-cell lymphocytosis (MBL) is a premalignant condition characterized by the presence of less than 5000/µL circulating clonal B cells in otherwise healthy individuals. Three subcategories have been identified according to the immunophenotypic features: CLL-like, CD5(+) atypical, and CD5(-) MBL. CLL-like MBL is by far the most frequent and best studied category and further divided in low-count [LC] and high-count [HC] MBL, based on a cutoff value of 500/µL clonal B cells. LC-MBL typically remains stable and probably does not represent a truly premalignant condition, but rather an age-related immune senescence. On the other hand, HC-MBL is closely related to CLL-Rai0, bearing similar immunogenetic profile, and is associated with an annual risk of progression to CLL requiring therapy at a rate of 1.1%. Currently there are no reproducible factors for evaluating the risk of progression to CLL. CD5(-) MBL is characterized by an immunophenotype consistent with marginal zone origin and displays many similarities with marginal zone lymphomas (MZL), mainly the splenic MZL. The cutoff value of 5000/µL clonal B cells cannot probably be applied in CD5(-) MBL, requiring a new definition to describe those cases.

Apoptotic and proliferative characteristics of proliferation centers in lymph node sections of patients with chronic lymphocytic leukemia.

We have analyzed the immunohistochemical expression of a wide range of molecules along with the proliferation rate separately in the proliferation centers (PCs) and in the rest of the tumor area, in lymph node or spleen sections of patients with chronic lymphocytic leukemia (CLL). Fas, FasL and c-FLIP were observed both within and outside the PCs in all cases. However, only the difference in FasL expression between the PCs and the non-PC areas attained statistical significance. Median survivin expression in the PCs was higher compared to the non-PC areas. Cleaved caspase 3 was expressed at very low levels both within and outside PCs, while BCL-2 protein was expressed at high levels in all cases in both tumor compartments. Multivariate analysis demonstrated that concurrent overexpression of Fas/FasL/c-FLIP in the PCs was correlated with worse outcome for progression-free survival as well as for overall survival.

Immunohistochemical analysis of IL-6, IL-8/CXCR2 axis, Tyr p-STAT-3, and SOCS-3 in lymph nodes from patients with chronic lymphocytic leukemia: correlation between microvascular characteristics and prognostic significance.

A number of studies have looked into the pathophysiological role of angiogenesis in CLL, but the results have often been inconsistent. We aimed to gain direct insight into the angiogenic process in lymph nodes involved by CLL, focusing on proangiogenic cytokines and microvessel morphometry. The tissue levels of VEGF, Th-2 cytokines IL-6 and IL-8, IL-8 receptor CXCR2, and tyrosine p-STAT-3/SOCS-3 axis modulating cytokine expression were evaluated immunohistochemically in 62 CLL/SLL cases. Microvascular characteristics were evaluated by image analysis. Results were analyzed with regard to clinicopathological characteristics. Proliferation centers (PCs) were less well vascularised compared to non-PC areas. IL-8 and CXCR2 expression was distinctly uncommon as opposed to IL-6, VEGF and SOCS-3, which were detected in the vast majority of cases. The latter two molecule expressions were more pronounced in the PCs in ∼ 40% of the cases. p-STAT-3 immunoreactivity was recorded in 66.67% of the cases with a predilection for PCs. Microvessel morphometry was unrelated to proangiogenic cytokines, p-STAT-3, SOCS-3, or survival. Microvascular caliber and VEGF expression were higher in Binet stage A, whereas IL-6 expression was higher in stage C. VEGF and p-STAT-3 exerted a favorable effect on progression, which remained significant in multivariate analysis, thereby constituting potential outcome predictors in CLL patients.

Combination of rituximab with chlorambucil as first line treatment in patients with mantle cell lymphoma: a highly effective regimen.

The optimal treatment approach for patients with mantle cell lymphoma (MCL) is not well defined. Intensive therapeutic regimens result in high response rates and prolonged progression-free survival but at the expense of significant toxicity. We report here our results of the administration of rituximab plus chlorambucil (R-Chl) as first line treatment in patients with MCL. Twenty consecutively diagnosed patients were treated with this combination in which an induction and a maintenance arm were included. During induction, rituximab was administered at a dose of 375 mg/m(2) on day 1, while chlorambucil was given afterward at a dose of 10 mg/day for 10 consecutive days for eight cycles and then as a single agent for an additional four cycles. Maintenance consisted of rituximab administration every 2 months for 1 year. Most patients had indolent disease features such as a low mantle-cell international prognostic index (MIPI) score. The overall response rate was 95% (90% CR, 5% PR). Among patients in CR, 78% presented a molecular remission. The 3-year progression-free survival was 89%. There were no serious side effects. These results show that the R-Chl combination could be an effective therapeutic option as first line treatment in MCL, especially for patients with indolent disease characteristics.