Integrative analysis of clinicopathological features defines novel prognostic models for mantle cell lymphoma in the immunochemotherapy era: a report from The North American Mantle Cell Lymphoma Consortium.

BACKGROUND: Patients with mantle cell lymphoma (MCL) exhibit a wide variation in clinical presentation and outcome. However, the commonly used prognostic models are outdated and inadequate to address the needs of the current multidisciplinary management of this disease. This study aims to investigate the clinical and pathological features of MCL in the immunochemotherapy era and improve the prognostic models for a more accurate prediction of patient outcomes. METHODS: The North American Mantle Cell Lymphoma Project is a multi-institutional collaboration of 23 institutions across North America to evaluate and refine prognosticators for front-line therapy. A total of 586 MCL cases diagnosed between 2000 and 2012 are included in this study. A comprehensive retrospective analysis was performed on the clinicopathological features, treatment approaches, and outcomes of these cases. The establishment of novel prognostic models was based on in-depth examination of baseline parameters, and subsequent validation in an independent cohort of MCL cases. RESULTS: In front-line strategies, the use of hematopoietic stem cell transplantation was the most significant parameter affecting outcomes, for both overall survival (OS, p < 0.0001) and progression-free survival (PFS, p < 0.0001). P53 positive expression was the most significant pathological parameter correlating with inferior outcomes (p < 0.0001 for OS and p = 0.0021 for PFS). Based on the baseline risk factor profile, we developed a set of prognostic models incorporating clinical, laboratory, and pathological parameters that are specifically tailored for various applications. These models, when tested in the validation cohort, exhibited strong predictive power for survival and showed a stratification resembling the training cohort. CONCLUSIONS: The outcome of patients with MCL has markedly improved over the past two decades, and further enhancement is anticipated with the evolution of clinical management. The innovative prognostic models developed in this study would serve as a valuable tool to guide the selection of more suitable treatment strategies for patients with MCL.

Outcomes of Richter's transformation of chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL): an analysis of the SEER database.

Richter's transformation (RT) is a rare complication arising in patients with chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) and is associated with an overall dismal outcome. The rarity of this entity poses many challenges in understanding its biology and outcomes seen and the optimal treatment approach. We utilized the SEER (Surveillance, Epidemiology and End Results) database to identify patients diagnosed with CLL/SLL between 2000 and 2016 and subsequently had a diagnosis of diffuse large B-cell lymphoma (DLBCL) or Hodgkin lymphoma (HL), thus capturing those who experienced an RT event. We compared the outcomes of those patients to those of patients in the database diagnosed with DLBCL without a preceding CLL/SLL diagnosis. We identified 530 patients who developed RT out of 74,116 patients diagnosed with CLL/SLL in the specified period. The median age at RT diagnosis was 66 years, and the median time from CLL/SLL diagnosis to RT development was roughly 4 years. Patients with RT had a dismal outcome with median overall survival of 10 months. We identified advanced Ann Arbor stage (III/IV) and prior treatment for CLL as predictors of worse outcome in patients with RT. Our study represents the largest dataset of patients with CLL/SLL and RT and adds to the existing literature indicating the poor outcomes for those patients.

Follicular large cleaved cell (centrocytic) lymphoma: an unrecognized variant of follicular lymphoma.

The World Health Organization classification of lymphoma recommends the subdivision of follicular lymphoma (FL) into 3 grades (FL1-3) based on the average number of centroblasts per high-power field in the neoplastic follicles, but does not recognize a form of FL characterized by a predominance of large cleaved cells (centrocytes) without enough centroblasts to meet the World Health Organization criteria for FL3. We have classified such cases as follicular large cleaved cell lymphoma (FLC) and, herein, describe the pathologic and clinical features of 72 cases of this entity. The features of FLC include a follicular growth pattern with pale follicles at low magnification and frequent follicular and/or interfollicular fibrosis. Cytologically, the cells are predominantly large cleaved cells with moderately coarse to fine chromatin, absent or inconspicuous nucleoli, and small to moderate amounts of pale cytoplasm. The mean nuclear diameter of the large cleaved cells was 10.1µ, approximately twice that of small lymphocytes and similar to centroblasts. The t(14;18) was present in 83% of the cases, and a high proportion expressed BCL2 (84%), BCL6 (100%), and CD10 (88%) and had high Ki67 proliferation (81%). The clinical features of patients with FLC were similar to those with other types of FL, and survival was excellent with anthracycline-based chemotherapy plus rituximab. FLC is a variant of follicular lymphoma which should be recognized in future lymphoma classifications because the diagnosis of FLC may be important for the selection of therapy.

Rituximab Improves the Outcome of Patients With Grade 3 Follicular Lymphoma Receiving Anthracycline-Based Therapy.

BACKGROUND: The combination of rituximab with chemotherapy has improved the outcome of patients with follicular lymphoma (FL). However, data on Grade 3 FL (FL3) and its subtypes are lacking. The aims of the study were to determine: (1) the clinical features and outcome of patients with FL3 treated with rituximab and anthracycline-based chemotherapy; and (2) the clinical significance of the 3 subtypes of FL3. PATIENTS AND METHODS: Eighty-seven patients with Grade 1/2 FL, 84 with FL3 including 46 FL3A, 17 FL3B, and 21 follicular large cleaved cell (FL3C), and 411 patients with diffuse large B-cell lymphoma (DLBCL) treated with rituximab and anthracycline-based chemotherapy, and a historical cohort of 167 patients with FL3 who received only anthracycline-based chemotherapy (FL3*) were included in this retrospective study. RESULTS: The FL3 group had a significantly better overall survival (OS) and event-free survival (EFS) compared with those with FL3* or DLBCL. No significant differences in OS were found among the 3 subtypes of FL3. However, patients with FL3B had a shorter EFS than those with FL3A and FL3C. Moreover, patients with FL3B had an outcome similar to those with DLBCL, whereas patients with FL3A and 3C had significantly better outcomes than those with DLBCL. Less than 50% of the patients with FL3B and less than 20% of the patients with FL3A and 3C have relapsed, and relapses were uncommon after 5 years. CONCLUSION: The use of rituximab with anthracycline-based chemotherapy significantly improved the survival of patients with FL3 and should be considered the benchmark by which other therapies for FL3 are evaluated in the future.

Isolated MYC cytogenetic abnormalities in diffuse large B-cell lymphoma do not predict an adverse clinical outcome.

In this study, we investigated the significance of MYC, BCL2 and BCL6 gene abnormalities in a cohort of 205 diffuse large B-cell lymphoma (DLBCL) patients studied by conventional and/or fluorescence in situ hybridization cytogenetic analysis. Combining these methods, 172 cases (84%) were classified as MYC-, 17 (8%) were MYC+/BCL2-/BCL6-, and 16 (8%) were double/triple-hit lymphomas (i.e. MYC+/BCL2+, MYC+/BCL6+, or MYC+/BCL2+/BCL6+). We found a significant difference in event-free survival (EFS) among the three groups (p = 0.02), with the double/triple-hit group having the worst EFS. Patients who were MYC+, but BCL2- and BCL6-, had the best EFS. We conclude that patients with MYC+ DLBCL, but without BCL2 or BCL6 abnormalities, do not have a worse outcome when compared to those who are MYC-. However, patients with double/triple-hit DLBCL have a very poor outcome and should be treated with aggressive or novel therapies.

MYC and BCL2 protein expression predicts survival in patients with diffuse large B-cell lymphoma treated with rituximab.

Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous disease and "double-hit" DLBCL, with both MYC and BCL2 translocations has a poor prognosis. In this study, we investigated whether MYC and BCL2 protein expression in tissue would predict survival in DLBCL. The study included 106 cases of de novo DLBCL treated with rituximab and cyclophosphamide, doxorubicin, vincristine and prednisone (R-CHOP) or CHOP-like regimens. The results were validated on an independent cohort of 205 DLBCL patients. Patients with low expression of BCL2 (≤30%) and MYC (≤50%) had the best prognosis, whereas those with high BCL2 (>30%) and MYC (>50%) had the worst outcome. In multivariate analysis, the combination of the BCL2 and MYC was an independent predictor of overall survival (OS) and event-free survival (EFS) (P = 0·015 and P = 0·005, respectively). The risk of death was nine times greater for patients with high BCL2 and MYC compared to those with low expression. High BCL2 and MYC was a strong predictor of poor OS (P < 0·001) and EFS (P = 0·0017) in patients with the germinal centre B-cell (GCB) type, but not in the non-GCB type. In DLBCL, high co-expression of MYC and BCL2 was an independent predictor of poor survival, and could be used to stratify patients for risk-adapted therapies.

Phase II trial of 131-Iodine tositumomab with high-dose chemotherapy and autologous stem cell transplantation for relapsed diffuse large B cell lymphoma.

The purpose of this study was to evaluate the standard outpatient dose of 131-Iodine tositumomab (75 cGy) combined with high-dose carmustine, etoposide, cytarabine, and melphalan (BEAM) followed by autologous stem cell rescue for the treatment of chemotherapy-sensitive relapsed or refractory, or high-risk first complete remission (CR) patients with diffuse large B cell non-Hodgkin's lymphoma (DLBCL). Forty patients with chemotherapy-sensitive persistent or relapsed or high/intermediate or high international prognostic index DLCBL were treated in a phase II trial combining 75 cGy 131-Iodine tositumomab with high-dose BEAM followed by autologous stem cell transplantation. The CR rate after transplantation was 78%, and the overall response rate was 80%. Short-term and long-term toxicities were similar to historical control patients treated with BEAM alone. With a median follow-up of 6 years (range, 3-10 years), the 5-year overall survival (OS) was 72% (95% confidence interval [CI], 55%-83%), and the 5-year progression-free survival (PFS) rate was 70% (95% CI, 53%-82%). The PFS and OS were encouraging in this group of chemotherapy-sensitive persistent, relapsed, or high-risk patients with DLBCL. A follow-up phase III trial with 131-Iodine tositumomab/BEAM vs rituximab/BEAM was planned based on this information.

Lymph node-induced immune tolerance in chronic lymphocytic leukaemia: a role for caveolin-1.

Emerging evidence indicates that the tumour microenvironment (TME) regulates the behaviour of chronic lymphocytic leukaemia (CLL). However, the precise mechanism and molecules involved in this process remain unknown. Gene expression profiles of CLL cells from lymph node (LN), bone marrow (BM) and peripheral blood (PB) indicate overexpression of a tolerogenic signature in CLL cells in lymph nodes (LN-CLL). Based on their role in B cell biology, the progression of CLL, or immune regulation, a few genes of this 83-gene signature were selected for further analyses. We observed a significant correlation between the clinical outcomes and the expression of CAV1 (P = 0·041), FGFR1 isoform 8 (P = 0·032), PTPN6 (P = 0·031) and ZWINT (P < 0·001). CAV1, a molecule involved in the regulation of tumour progression in other cancers, was seven-fold higher in LN-CLL cells compared to BM- and PB-CLL cells. Knockdown of CAV1 expression in CLL cells resulted in significantly decreased migration (P = 0·016) and proliferation (P = 0·04). When CAV1 was knocked down in B and T cell lines, we observed an inability to form immune synapses. Furthermore, CAV1 knockdown in CLL cells impaired their ability to form immune synapses with autologous T lymphocytes and allogeneic, healthy T cells. Subsequent analyses of microarray data showed differential expression of cytoskeletal genes, specifically those involved in actin polymerization. Therefore, we report a novel role for CAV1 in tumour-induced immunosuppression during the progression of CLL.

Late relapse in patients with diffuse large B-cell lymphoma.

The outcomes for 162 patients with diffuse large B-cell lymphoma treated with a CHOP (cyclophosphamide, doxorubicin, vincristine, prednisolone)-like regimen who obtained a complete remission and who subsequently relapsed after ≥5 years of remission (late relapse, N=30), or <5 years of remission (early relapse, N=132), were compared. The late relapsing patients had better prognostic characteristics at diagnosis, such as stage I/II disease (73% vs. 49%, P=0·04), a normal lactic dehydrogenase (77% vs. 48%, P=0·01), and a Karnofsky performance score of ≥80 (100% vs. 86%, P=0·01). The 3-year survival after relapse was better in late relapsing patients (48% vs. 25%, P=0·03), but the survival at 5 years (32% vs. 20%) and 10 years (13% vs. 14%) after relapse was not different. A multivariate analysis of factors predicting survival after relapse found age (P<0·0001) and presence of B-symptoms (P=0·03) to predict survival, but not early versus late relapse. A small percentage of the late relapsing patients can have a prolonged second remission. However, the overall survival from the time of relapse was not different between early and late relapsing patients with most succumbing to lymphoma.

Hedgehog-induced survival of B-cell chronic lymphocytic leukemia cells in a stromal cell microenvironment: a potential new therapeutic target.

B-cell chronic lymphocytic leukemia (B-CLL) is characterized by an accumulation of neoplastic B cells due to their resistance to apoptosis and increased survival. Among various factors, the tumor microenvironment is known to play a role in the regulation of cell proliferation and survival of many cancers. However, it remains unclear how the tumor microenvironment contributes to the increased survival of B-CLL cells. Therefore, we studied the influence of bone marrow stromal cell-induced hedgehog (Hh) signaling on the survival of B-CLL cells. Our results show that a Hh signaling inhibitor, cyclopamine, inhibits bone marrow stromal cell-induced survival of B-CLL cells, suggesting a role for Hh signaling in the survival of B-CLL cells. Furthermore, gene expression profiling of primary B-CLL cells (n = 48) indicates that the expression of Hh signaling molecules, such as GLI1, GLI2, SUFU, and BCL2, is significantly increased and correlates with disease progression of B-CLL patients with clinical outcome. In addition, SUFU and GLI1 transcripts, as determined by real-time PCR, are significantly overexpressed and correlate with adverse indicators of clinical outcome in B-CLL patients, such as cytogenetics or CD38 expression. Furthermore, selective down-regulation of GLI1 by antisense oligodeoxynucleotides (GLI1-ASO) results in decreased BCL2 expression and cell survival, suggesting that GLI1 may regulate BCL2 and, thereby, modulate cell survival in B-CLL. In addition, there was significantly increased apoptosis of B-CLL cells when cultured in the presence of GLI1-ASO and fludarabine. Together, these results reveal that Hh signaling is important in the pathogenesis of B-CLL and, hence, may be a potential therapeutic target.

Molecular basis of aggressive disease in chronic lymphocytic leukemia patients with 11q deletion and trisomy 12 chromosomal abnormalities.

In B-cell chronic lymphocytic leukemia (CLL), Rai stage, immunoglobulin gene mutational status, chromosomal abnormalities, CD38 and ZAP-70 expression were used as prognostic markers. In this study, to understand the molecular basis of chromosomal abnormalities leading to tumor progression, 90 CLL patients were grouped into poor prognosis (with 11q deletion and trisomy 12) and good prognosis (with normal karyotype and 13q deletion) and their clinical outcome was assessed. Gene expression profiles of 35 CLL samples with poor outcome (11q deletion, n=9; trisomy 12, n=5) and good outcome (13q deletion, n=13; normal karyotype, n=8) were analyzed using oligonucleotide microarray. Significance analysis of microarray (SAM) identified 27 differentially expressed genes between these two subgroups with significant overexpression of ATF5 and underexpression of CDC16, PCDH8, SLAM, MNDA and ATF2 in CLL patients with poor outcome. ATF5 gene expression in CLL was further studied because of its role in the regulation of cell cycle progression/differentiation and apoptosis. The overexpression of ATF5 was confirmed by real-time PCR using 39 CLL samples from the poor and good outcome groups. ATF5 was significantly (p<0.001) overexpressed in the poor outcome group. Furthermore, ATF5 expression was significantly higher in the 11q deletion as well as trisomy 12 group alone compared to the 13q deletion and normal karyotype groups. ATF5 overexpression was also associated with significantly (p=0.04) shorter time to treatment. Similarly, expression of five underexpressed genes also correlated with longer time to treatment. Thus, this report demonstrates that ATF5 may be one of the key genes involved in increased proliferation and survival in 11q deletion or trisomy 12, whereas CD16, CD86, SLAM, MNDA and ATF2 may be involved in the decreased proliferation of CLL cells with 13q deletion or normal karyotype.

Phase I trial of (90)Y-ibritumomab tiuxetan in patients with relapsed B-cell non-Hodgkin's lymphoma following high-dose chemotherapy and autologous stem cell transplantation.

Between January 2001 and September 2005, 19 patients with progressive B-cell non-Hodgkin's lymphoma were treated with a cohort-specific dose of yttrium-90 ibritumomab tiuxetan (0.10 - 0.20 mCi/kg) to determine appropriate dosing in patients who had previously received high-dose chemotherapy and autologous stem cell transplantation (ASCT). Patients were required to have adequate end organ function and bone marrow status. Patients had been treated with a median of three prior therapies (range, 1 - 9). The median time from ASCT to radioimmunotherapy was 28 months. Hematologic toxicities were dose-limiting and included grade 3 - 4 thrombocytopenia (53%), neutropenia (32%), and anemia (21%). The majority of grade 3 - 4 events occurred at the 0.2 mCi/kg dose level. Nine patients responded (complete response, complete response unconfirmed, or partial response) to the therapy. At a median follow-up of 37 months, the 1-year event-free and overall survival rates were 26% and 57%, respectively. A dose of 0.2 mCi/kg ibritumomab tiuxetan is safe and effective for patients with progressive disease after high-dose chemotherapy and ASCT.

Bulky lymphadenopathy with poor clinical outcome is associated with ATM downregulation in B-cell chronic lymphocytic leukemia patients irrespective of 11q23 deletion.

B-cell chronic lymphocytic leukemia (B-CLL) is the most common B-cell leukemia among older populations in Western countries. The clinical course of B-CLL is heterogeneous: in some patients the disease course is indolent, in others it is aggressive. The B-CLL subgroups with chromosome 11q23 deletion have been associated with aggressive disease course involving ATM deletion, extensive bulky lymphadenopathy (BLA), and inferior clinical outcome. Using real-time reverse transcriptase-polymerase chain reaction, we found that ATM was consistently underexpressed in B-CLL patients with BLA, irrespective of 11q23 deletion status. In addition, B-CLL patients who presented with BLA had a significantly shorter time to treatment (2 months) than did patients without BLA (74 months). Moreover, gene expression analysis in B-CLL patients with and without BLA revealed differences in expression for genes involved in apoptosis, cell cycle, and cell adhesion. These results indicate an association between BLA and reduced expression of ATM, suggesting a role for ATM in disease progression in B-CLL.

A significant diffuse component predicts for inferior survival in grade 3 follicular lymphoma, but cytologic subtypes do not predict survival.

Grade 3 follicular lymphoma (FL3) is thought to have an aggressive clinical course. On the basis of possible biologic differences, the new World Health Organization (WHO) classification of lymphoma suggests further subdivision of FL3 into grades 3a and 3b and states that the percentage of involvement by diffuse large B-cell lymphoma (DLBCL) should also be reported. However, the clinical implications of these features are unclear. Therefore, we studied 190 newly diagnosed patients with lymph node-based FL3 who received anthracycline-containing combination chemotherapy. The follicular component was subclassified as grade 3a (FL3a) or grade 3b (FL3b) according to the WHO criteria, or as follicular large cleaved cell type (FLC). The percentage of a diffuse component, if present, was also recorded. Of the 190 cases, there were 107 FL3a (56%), 53 FL3b (28%), and 30 FLC (16%) cases. Diffuse areas were seen in 72 cases (31 FL3a, 28 FL3b, and 13 FLC). There were no significant differences in the clinical characteristics, overall survival, or event-free survival between patients with grades FL3a, FL3b, or FLC. However, those cases with a predominant diffuse component (> 50% diffuse) had a significantly worse overall survival (P =.0037) and event-free survival (P =.012). Therefore, we conclude that the subdivision of FL3 into cytologic subtypes does not appear to be important clinically. However, patients with FL3 having a diffuse component of more than 50% have an inferior survival that is similar to the survival of those with DLBCL.