Microvessel density and expression of vascular endothelial growth factor and its receptors in diffuse large B-cell lymphoma subtypes

Vascular Growth in Lymphomas: Angiogenesis and Alternative Ways

The formation of new blood vessels is a critical process for tumor growth and may be achieved through different mechanisms. Angiogenesis represents the first described and most studied mode of vessel formation, but tumors may also use alternative ways to secure blood supply and eventually acquire resistance to anti-angiogenic treatments. These non-angiogenic mechanisms have been described more recently, including intussusceptive microvascular growth (IMG), vascular co-option, and vasculogenic mimicry. Like solid tumors, angiogenic and non-angiogenic pathways in lymphomas play a fundamental role in tumor growth and progression. In view of the relevant prognostic and therapeutic implications, a comprehensive understanding of these mechanisms is of paramount importance for improving the efficacy of treatment in patients with lymphoma. In this review, we summarize the current knowledge on angiogenic and non-angiogenic mechanisms involved in the formation of new blood vessels in Hodgkin's and non-Hodgkin's lymphomas.

Histopathological Evaluation of Angiogenic Markers in Non-Hodgkin's Lymphoma

Background Angiogenesis plays a key role in the development, maintenance, and progression of tumor. The incidence of non-Hodgkin's lymphoma (NHL) is increasing from the past three decades.

Materials and Methods The aim of the study is to evaluate microvessel density (MVD) using CD34 monoclonal antibody and vascular endothelial growth factor (VEGF) using monoclonal antibody that were studied in pretreatment paraffin-embedded tissue samples of 60 cases.

Results MVD was found to be increased in parallel with increasing grade of tumor. B-NHL had a mean MVD of 79.5 ± 8.8 (no./mm2), while T-NHL had a mean MVD of 183 ± 37.6 (no./mm2). VEGF expression was seen in 42 cases (70%), 20 cases (33.3%) showed strong VEGF expression, and the remainder showed either weak (36.6%) or no (30%) staining. Strong VEGF expression is seen in 100% cases of T-NHL and 77.7% cases of B-NHL. Mean MVD and VEGF expression was found to be correlated significantly with the histological grade of NHL (p = 0.001 and p = 0.000, respectively). Average microvessel counts were 53, 82.9, and 130.8 vessels (no./mm2) for negative, weak, and strong VEGF staining, respectively. These differences were statistically significant (p = 0.005 for strong vs. negative and p = 0.091 for strong vs. weak VEGF staining individually).

Conclusion As the grade of tumor progresses, the angiogenic potential also advances which seems to depend on VEGF. The presence of higher MVD in high-grade lymphomas can be utilized for antiangiogenic drugs.

Risk stratification model based on VEGF and International Prognostic Index accurately identifies low-risk diffuse large B-cell lymphoma patients in the rituximab era

Vascular endothelial growth factor affects the invasiveness of solid tumors by regulating angiogenesis. However, it is not clear whether VEGF could be used to predict the prognosis of DLBCL in the era of rituximab-based immunotherapy. We conducted a retrospective study to explore response to therapy and the prognostic value of VEGF on DLBCL in the rituximab era. The subjects were 65 patients with a histological diagnosis of DLBCL from the Affiliated Hospital of Xuzhou Medical University. Kaplan-Meier analysis was performed to estimate the cumulative survival rate of patients with different VEGF and IPI levels, and comparisons between groups were made using the log-rank test. DLBCL patients with elevated VEGF were more likely to have extranodal involvement, advanced stage, Myc/Bcl-2 double expression, and a higher Ki-67 score. Elevated VEGF was associated with poor therapeutic response and survival. When patients were divided into low, low-intermediate, high-intermediate and high-risk groups using the V-IPI model based on VEGF and IPI, PFS rates were 94.4, 74.1, 40.6 and 14.8%, respectively. This model better identified low-risk patients than IPI (85.9, 88.9, 37 and 7.8%). Our results demonstrate that VEGF predicts therapeutic response in DLBCL and the V-IPI model accurately predicts PFS of low-risk DLBCL in the rituximab era.

Immunohistochemical Markers of Tumor Microenvironment as Prognostic Predictors in Diffuse Large B-Cell Lymphoma: Study from an Oncology Centre in South India

Introduction Diffuse large B-cell lymphoma (DLBCL) accounts for 60% of lymphomas in India. Although the survival of DLBCL patients has improved following the addition of rituximab, a subset of patients do not respond well to therapy. Among the several factors responsible for this varied response, tumor microenvironment is considered to be crucial. This study is a search for such prognostic markers in the tumor microenvironment.

Materials and Methods A total of 97 patients were selected, of whom 34 were treated with the CHOP regimen and 63 with RCHOP. Immunohistochemistry for CD68 was performed to study the stromal-1 signature and CD34 for stromal-2 signature.

Results There was a significant increase in the counts of CD68-positive cells among patients free of events. CD34 count was higher in patients with events in both CHOP and RCHOP groups.

Conclusion Additional assessment of stromal microenvironment along with the cell of origin might predict the clinical outcome better in DLBCL.

Development of diffuse large B-cell lymphoma after sofosbuvir-ledipasvir treatment for chronic hepatitis C: A case report and literature review

Recently, treatments for chronic hepatitis C virus (HCV) infection have significantly improved by the development of direct-acting antiviral agents (DAAs) and almost all patients with HCV can complete antiviral treatment without apparent adverse events. Malignant lymphoma, particularly B-cell non-Hodgkin's lymphoma, is one of the extrahepatic manifestations associated with chronic HCV infection. The effectiveness of anti-HCV therapy with DAAs for B-cell non-Hodgkin's lymphoma has been demonstrated in recent reports, whereas late-onset B-cell non-Hodgkin's lymphoma after HCV eradication with DAAs has occasionally been reported. In the present study, a 77-year-old man with chronic hepatitis C and intermediate liver cancer risk received sofosbuvir-ledipasvir treatment for 12 weeks. Two months following the end of antiviral therapy, he had achieved sustained virologic response for 8 weeks. However, the patient occasionally found swelling of the right cervical lymph nodes without any subjective symptoms. Lymph node biopsy revealed diffuse large B-cell lymphoma and whole-body ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography with computed tomography showed increased FDG uptake in the right cervical, right submandibular, mediastinal and mesenteric lymph nodes. The patient received six courses of rituximab, cyclophosphamide, doxorubicin, vincristine and prednisolone chemotherapy and achieved complete response at 8 months after chemotherapy initiation. Thus, the development of lymphoid malignancies may arise, even after HCV eradication with DAAs. Therefore, clinicians should be aware of such risks during and after antiviral treatment with DAAs.

B-cell non-Hodgkin lymphoma: importance of angiogenesis and antiangiogenic therapy

Angiogenesis is critical for the initiation and progression of solid tumors, as well as hematological malignancies. While angiogenesis in solid tumors has been well characterized, a large body of investigation is devoted to clarify the impact of angiogenesis on lymphoma development. B-cell non-Hodgkin lymphoma (B-NHL) is the most common lymphoid malignancy with a highly heterogeneity. The malignancy remains incurable despite that the addition of rituximab to conventional chemotherapies provides substantial improvements. Several angiogenesis-related parameters, such as proangiogenic factors, circulating endothelial cells, microvessel density, and tumor microenvironment, have been identified as prognostic indicators in different types of B-NHL. A better understanding of how these factors work together to facilitate lymphoma-specific angiogenesis will help to design better antiangiogenic strategies. So far, VEGF-A monoclonal antibodies, receptor tyrosine kinase inhibitors targeting VEGF receptors, and immunomodulatory drugs with antiangiogenic activities are being tested in preclinical and clinical studies. This review summarizes recent advances in the understanding of the role of angiogenesis in B-NHL, and discusses the applications of antiangiogenic therapies.

Apatinib exerts anti-tumor activity to non-Hodgkin lymphoma by inhibition of the Ras pathway

Apatinib is a tyrosine kinase inhibitor that selectively targets vascular endothelial growth factor receptor-2 (VEGFR-2). Although apatinib has shown promising anti-tumor activity against several types of tumor, its role and underlying mechanism against non-Hodgkin lymphoma (NHL) remain to be explored. Here, we report that apatinib dramatically inhibited in vitro the proliferation of various human NHL cell lines, including Burkitt lymphoma (BL), mantle cell lymphoma (MCL), and diffuse large B-cell lymphoma (DLBCL), in a dose-dependent manner. Moreover, administration of apatinib markedly delayed tumor growth in vivo in a xenograft mouse model derived from human DLBCL OCI-ly3 cells, in association with significantly prolonged survival of tumor-bearing mice. Mechanistically, apatinib suppressed activation of VEGFR2 (manifested by reduced VEGFR2 phosphorylation), accompanied by inhibition of the Ras pathway (reflected by down-regulation Ras, Raf, pMEK1/2, pERK1/2) in OCI-ly1 (GCB subtype of DLBCL) and SU-DHL2 (ABC subtype of DLBCL) cells. Of note, apatinib sharply impaired angiogenesis in vivo in tumor tissues. Together, these results indicate that apatinib displays a marked cytotoxic activity against various types of NHL cells (including BL, MCL, and GCB- or ABC-DLBCL) both in vitro and in vivo. They also suggest that anti-NHL activity of apatinib might be associated with inhibition of tumor cell growth and induction of apoptosis as well as anti-angiogenesis by targeting VEGFR2 and its downstream Ras/Raf/MEK/ERK pathway.

Thalidomide enhanced the efficacy of CHOP chemotherapy in the treatment of diffuse large B cell lymphoma: A phase II study

Cyclophosphamide, doxorubicin, vincristine, and prednisolone plus rituximab (R-CHOP) is the standard treatment for patients with diffuse large B cell lymphoma (DLBCL). However, rituximab cannot be popularly applied in a considerable number of patients with DLBCL because of economic reasons. To develop a new regimen to improve the outcome of these patients is extremely important. In our study, sixty five patients with DLBCL were randomly assigned to thalidomide plus CHOP group (n=32) or to CHOP alone group (n=33). Objective response rates (ORR) and complete remission rates (CRR) were 96.7% and 80.6% in T-CHOP group versus 78.9 % and 57.8 % in CHOP group, respectively (P <0.05). At a median follow-up of 96 months, median PFS for T-CHOP group was still not reached yet, and in CHOP group it was 22.9 months (95% CI [0-50.4]). (P=0.163). Median overall survival (OS) for T-CHOP group was also not reached, and the estimated median OS for CHOP group was 83.5 months, the difference of OS between the two groups is not significant (p=0.263). But, in patients with Bcl-2 positive and Bcl-6 negative, the median PFS in T-CHOP group was longer than that in CHOP group (111.0 vs 8.5 months (P=0.017). In addition, thalidomide did not significantly increase the grade 3/4 toxicity of CHOP. We concluded that the addition of thalidomide to the CHOP regimen significantly improved the CRR and showed a trend of improving clinical outcome in patients with DLBCL, especially for patients with Bcl-2 positive and Bcl-6 negative B-cell phenotype, without increased toxicity.

The role of the tumor microenvironment in HIV-associated lymphomas

There has been considerable interest in the role of the lymphoma microenvironment. Despite the use of highly active antiretroviral therapy (HAART), AIDS-related diffuse large-B-cell lymphoma remains common and HIV-relatedHIV-associated classical Hodgkin's lymphoma is increasing in incidence. Less is known about the impact HIV and HAART have on the lymphoma microenvironment. AIDS-related diffuse large B-cell lymphoma is highly angiogenic, demonstrates increased lymphoblastic histology, proliferation, increased activated cytotoxic T cells, reduced CD4(+) and FOXP3(+) T cells, but no differences in tumor-associated macrophages. Early initiation of HAART improves immunosurveillance, but cases without viral antigens appear able to avoid immunologic reaction. Increased T cell infiltrates seen with HAART treatment in HIV-related classical Hodgkin's lymphoma may contribute to malignant cell growth.

A phosphodiesterase 4B-dependent interplay between tumor cells and the microenvironment regulates angiogenesis in B-cell lymphoma

Angiogenesis associates with poor outcome in diffuse large B-cell lymphoma (DLBCL), but the contribution of the lymphoma cells to this process remains unclear. Addressing this knowledge gap may uncover unsuspecting proangiogenic signaling nodes and highlight alternative antiangiogenic therapies. Here we identify the second messenger cyclic-AMP (cAMP) and the enzyme that terminates its activity, phosphodiesterase 4B (PDE4B), as regulators of B-cell lymphoma angiogenesis. We first show that cAMP, in a PDE4B-dependent manner, suppresses PI3K/AKT signals to down-modulate VEGF secretion and vessel formation in vitro. Next, we create a novel mouse model that combines the lymphomagenic Myc transgene with germline deletion of Pde4b. We show that lymphomas developing in a Pde4b-null background display significantly lower microvessel density in association with lower VEGF levels and PI3K/AKT activity. We recapitulate these observations by treating lymphoma-bearing mice with the FDA-approved PDE4 inhibitor Roflumilast. Lastly, we show that primary human DLBCLs with high PDE4B expression display significantly higher microvessel density. Here, we defined an unsuspected signaling circuitry in which the cAMP generated in lymphoma cells downmodulates PI3K/AKT and VEGF secretion to negatively influence vessel development in the microenvironment. These data identify PDE4 as an actionable antiangiogenic target in DLBCL.

Anti-apoptotic role and clinical relevance of neurotrophins in diffuse large B-cell lymphomas

Background:

Diffuse large B-cell lymphoma (DLBCL) is a fatal malignancy that needs to identify new targets for additional therapeutic options. This study aimed to clarify the clinical and biological significance of endogenous neurotrophin (nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF)) in DLBCL biopsy samples and cell lines.

Methods:

We analysed expression of NGF, BDNF, and their receptors (Trk, p75^NTR) in 51 biopsies and cell lines by immunohistochemistry, immunofluorescence, and western blotting. To investigate the biological role of BDNF/TrkB/p75^NTR axis, effects of neurotrophin signalling inhibition were determined on tumour cell survival and vascular endothelial growth factor (VEGF) secretion. The pharmacological pan-Trk inhibitor K252a was used for in vitro and in vivo studies.

Results:

A BDNF/TrkB axis was expressed in all biopsies, which was independent of the germinal centre B-cell (GCB)/non-GCB profile. p75^NTR, TrkB, and BDNF tumour scores were significantly correlated and high NGF expression was significantly associated with MUM1/IRF4, and the non-GCB subtype. Diffuse large B-cell lymphoma cell lines co-expressed neurotrophins and their receptors. The full-length TrkB receptor was found in all cell lines, which was also phosphorylated at Tyr-817. p75^NTR was associated to Trk and not to its cell death co-receptor sortilin. In vitro, inhibition of neurotrophin signalling induced cell apoptosis. K252a caused cell apoptosis, decreased VEGF secretion, and potentiated rituximab effect, notably in less rituximab-sensitive cells. In vivo, K252a significantly reduced tumour growth and potentiated the effects of rituximab in a GCB-DLBCL xenograft model.

Conclusions:

This work argues for a pro-survival role of endogenous neurotrophins in DLBCLs and inhibition of Trk signalling might be a potential treatment strategy for rituximab resistant subgroups.

Shaping of the tumor microenvironment: Stromal cells and vessels

Lymphomas develop and progress in a specialized tissue microenvironment such as bone marrow as well as secondary lymphoid organs such as lymph node and spleen. The lymphoma microenvironment is characterized by a heterogeneous population of stromal cells, including fibroblastic reticular cells, nurse-like cells, mesenchymal stem cells, follicular dendritic cells, and inflammatory cells such as macrophages, T- and B-cells. These cell populations interact with the lymphoma cells to promote lymphoma growth, survival and drug resistance through multiple mechanisms. Angiogenesis is also recognized as an important factor associated with lymphoma progression. In recent years, we have learned that the interaction between the malignant and non-malignant cells is bidirectional and resembles, at least in part, the pattern seen between non-neoplastic lymphoid cells and the normal microenvironment of lymphoid organs. A summary of the current knowledge of lymphoma microenvironment focusing on the cellular components will be reviewed here.

The tumour microenvironment in B cell lymphomas

B cell lymphomas are cancers that arise from cells that depend on numerous highly orchestrated interactions with immune and stromal cells in the course of normal development. Despite the recent focus on dissecting the genetic aberrations within cancer cells, it has been increasingly recognized that tumour cells retain a range of dependence on interactions with the non-malignant cells and stromal elements that constitute the tumour microenvironment. A fundamental understanding of these interactions gives insight into the pathogenesis of most B cell lymphomas and, moreover, identifies novel therapeutic opportunities for targeting oncogenic pathways, both now and in the future.

R-CHOP with or without bevacizumab in patients with previously untreated diffuse large B-cell lymphoma: final MAIN study outcomes

Vascular endothelial growth factor is involved in lymphoma growth, suggesting a potential role for anti-vascular endothelial growth factor therapies in hematologic malignancies. In this phase III study, patients with CD20-positive diffuse large B-cell lymphoma were randomized to rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone plus either placebo (R-CHOP) or bevacizumab (RA-CHOP). Treatment was administered every 21 (8 cycles) or 14 days (6 cycles plus 2 rituximab cycles) as per institutional practice. An early analysis of risk/benefit by the Data and Safety Monitoring Board showed that RA-CHOP increased cardiotoxicity without prolonging progression-free survival compared with R-CHOP, and the trial was stopped early. The study protocol was amended to allow for 12 additional months of follow up to evaluate safety. With 787 patients enrolled, median follow up was 23.7 and 23.6 months for R-CHOP and RA-CHOP, respectively. Median progression-free survival for R-CHOP and RA CHOP was 42.9 and 40.2 months, respectively (hazard ratio=1.09; P=0.49). The proportion of deaths was identical for R-CHOP (83 of 387, 21%) and RA-CHOP (82 of 390, 21%). Relative to R-CHOP, RA-CHOP had a higher rate of left ventricular ejection fraction perturbation (18% vs. 8%; odds ratio=2.51; 95% confidence interval (CI): 1.60-3.93) and congestive heart failure (16% vs. 7%; odds ratio=2.79; 95%CI: 1.72-4.54). Bevacizumab added to R-CHOP increased cardiac events, without increasing efficacy, arguing against further evaluation of RA-CHOP in patients with diffuse large B-cell lymphoma. The MAIN study is registered at clinicaltrials.gov identifier:00486759.

CD163 expression was associated with angiogenesis and shortened survival in patients with uniformly treated classical Hodgkin lymphoma

Background

Recent studies have reported the prognostic value of tissue-associated magrophages (TAMs) in classical Hodgkin lymphoma (cHL). In addition, TAMs are implicated in the tumor angiogenesis. In this study, we examined the prognostic relevance of TAMs in relation to vascular endothelial growth factor (VEGF) expression and angiogenesis in uniformly treated cases of cHL.

Methods

Diagnostic tissue from 116 patients with ABVD-treated cHL was evaluated retrospectively by immunohistochemical analysis for CD68, CD163 and VEGF expression and for CD31 expression as a measure of microvessel density (MVD).

Results

High CD163 expression (≥35% of cellularity) correlated with VEGF expression (Pearson’s Chi-square test, P = 0.008) and MVD (Spearman correlation coefficient 0.310, P<0.001). High CD163 expression was associated with inferior event-free survival (EFS, P = 0.005) and overall survival (OS, P<0.001) in univariate analysis. In multivariate analysis, high CD163 expression was strongly associated with inferior EFS (P = 0.043) and OS (P = 0.008). Patients with high MVD had a lower OS than those with low MVD, but the difference was not significant (P = 0.071, respectively). While high expression of CD68 was also associated with inferior EFS (P = 0.007), it showed no correlation with VEGF or MVD.

Conclusions

Our data confirms that CD163 expression provides independent prognostic information in cHL. The correlation of CD163 with VEGF expression and MVD suggests the role of CD163-positive cells in tumor angiogenesis of cHL.

Correlation of dynamic contrast-enhanced MRI perfusion parameters with angiogenesis and biologic aggressiveness of rectal cancer: Preliminary results

PURPOSE

To investigate whether quantitative parameters derived from dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) are correlated with angiogenesis and biologic aggressiveness of rectal cancer.

MATERIALS AND METHODS

A total of 46 patients with rectal cancer underwent DCE-MRI. Using a two-compartmental model, quantitative parameters (K(trans) , kep , ve , and iAUC) were calculated from the whole-transverse region of interest (ROI) and high K(trans) area ROI of entire tumors. Histological specimens were analyzed for tumor size; T/N stage; lymphatic, vascular, perineural invasion; expression of epidermal growth factor receptor (EGFR); and KRAS gene mutations. Tumor angiogenesis was evaluated based on the microvessel density (MVD) and the expression level of the vascular endothelial growth factor. Correlations of the DCE-MRI parameters with histological markers and angiogenesis were determined using Student's t-test and analysis of variance (ANOVA).

RESULTS

The mean kep from high K(trans) area ROIs showed a significantly positive correlation with MVD (P  =  0.030, r  =  0.514, R(2)   =  0.264). The mean kep from the whole-transverse ROIs showed a significant inverse correlation with T stage (T1 vs. T2-4, P  =  0.021). EGFR-positive cancer displayed higher mean K(trans) (P  =  0.045) and kep (P  =  0.038) than EGFR-negative cancer in whole-transverse ROIs.

CONCLUSION

These preliminary results suggest that the determination of kep of high K(trans) area permits the noninvasive estimation of tumor angiogenesis in rectal cancer and that DCE-MRI parameters can be used as imaging biomarkers to predict the biologic aggressiveness of the tumor and patient prognosis.

The role of angiogenesis in human non-Hodgkin lymphomas

The role of angiogenesis in the growth of lymphomas and survival of patients with leukemias and other hematological malignancies has become evident since 1994. Angiogenic factors, such as vascular endothelial growth factor and its receptors together with other tumor microenvironment components, including myelo-monocytic cell, mast cells, endothelial progenitor cells, and circulating endothelial cells, have been shown to be important in the progression and maintenance of lymphoproliferative disorders. In this review article, we present an overview of the literature focusing on the relationship between angiogenesis and disease progression and the recent advantages in the antiangiogenic treatment in human non-Hodgkin lymphomas.

A phase II study of sorafenib (BAY 43-9006) in recurrent diffuse large B cell lymphoma: an eastern cooperative oncology group study (E1404)

Patients with diffuse large B cell lymphoma (DLBCL) who are not candidates for or recur after autologous stem cell transplant have a poor overall prognosis. We conducted a phase II study of sorafenib (formerly BAY 43-9006) in the treatment of relapsed DLBCL. Fourteen patients were enrolled and assessed for response. Median number of cycles administered was 3 (range, 1-12). Common grade 3 toxicities included fatigue (29%), rash/desquamation (21%) and diarrhea (14%). One complete response (CR) was observed (the 14th patient enrolled). Response rate was 7% (90% CI, 0.4 - 30%). Duration of response was 6 months. Median progression-free survival (PFS) was 2 months (90% CI, 1 - 5 months). Median overall survival (OS) was 9 months (90% CI, 5 - 16 months). Although sorafenib has demonstrated activity in solid malignancies it demonstrated low single agent activity in treatment of DLBCL.

Sorafenib inhibits lymphoma xenografts by targeting MAPK/ERK and AKT pathways in tumor and vascular cells

The anti-lymphoma activity and mechanism(s) of action of the multikinase inhibitor sorafenib were investigated using a panel of lymphoma cell lines, including SU-DHL-4V, Granta-519, HD-MyZ, and KMS-11 cell lines. In vitro, sorafenib significantly decreased cell proliferation and phosphorylation levels of MAPK and PI3K/Akt pathways while increased apoptotic cell death. In vivo, sorafenib treatment resulted in a cytostatic rather than cytotoxic effect on tumor cell growth associated with a limited inhibition of tumor volumes. However, sorafenib induced an average 50% reduction of tumor vessel density and a 2-fold increase of necrotic areas. Upon sorafenib treatment, endothelial and tumor cells from SU-DHL-4V, Granta-519, and KMS-11 nodules showed a potent inhibition of either phospho-ERK or phospho-AKT, whereas a concomitant inhibition of phospho-ERK and phospho-AKT was only observed in HD-MyZ nodules. In conclusion, sorafenib affects the growth of lymphoid cell lines by triggering antiangiogenic mechanism(s) and directly targeting tumor cells.

Prognostic role of tumor-associated macrophages and angiogenesis in classical Hodgkin lymphoma

We studied by immunohistochemistry CD68 + tumor-associated macrophages (TAMs) and angiogenesis in 121 consecutive cases of uniformly treated classical Hodgkin lymphoma (cHL). High TAM count showed a significant correlation with age ≥ 45, mixed cellularity subtype and high β₂-microglobulin level. Vessel density (VD) was unrelated to clinicopathological features, while a significant correlation was found between TAM count and VD. Patients with high TAMs showed a trend toward reduced progression-free survival and significantly shorter overall survival (OS). No correlation was found between VD and survival. At multivariate analysis, bulky disease was an independent predictor of reduced progression-free survival, while independent adverse prognostic factors for OS were male sex, age ≥ 45, advanced stage and bulky disease. High TAM count results in an adverse overall outcome in cHL and is significantly correlated to VD. Since VD has no prognostic relevance, the adverse effect of TAMs is presumably unrelated to angiogenesis.

Perfusion and flow extraction product as potential discriminators in untreated follicular and diffuse large B cell lymphomas using volume perfusion CT with attempt at histopathologic explanation

OBJECTIVE

The purpose of this article is to measure perfusion parameters, including transit constant (K(trans)), in untreated follicular and diffuse large B cell lymphoma using volume perfusion CT, to establish their discriminating role and to search for a possible histopathologic background.

SUBJECTS AND METHODS

Between January 2010 and June 2011, 46 consecutive patients with untreated histologically confirmed follicular lymphoma (n = 16) or diffuse large B cell lymphoma (n = 30) were enrolled. A 40-second volume perfusion CT of the tumor bulk using 6.9-cm z-axis coverage and a total of 26 volume measurements was performed. Blood flow (BF), blood volume (BV), and K(trans) were determined. Tumor size was recorded as the product of long- and short-axis diameters. In 13 of 46 patients, pathologic specimens of an appropriate size were available for assessment of microvessel density (MVD) and microvascular luminal diameter for comparison with volume perfusion CT measurements.

RESULTS

Mean BF, BV, and K(trans) values were significantly higher in follicular lymphoma than in diffuse large B cell lymphoma, even after controlling for patient age and tumor size (p < 0.05, respectively). Although MVD was slightly, but not significantly, higher in follicular lymphoma versus diffuse large B cell lymphoma (p > 0.05), microvascular luminal diameter was significantly larger in follicular lymphoma than in diffuse large B cell lymphoma (p < 0.05). We defined cutoff values for BF, BV, and K(trans). If the cutoff points are met for all three parameters, the overall accuracy for correctly identifying diffuse large B cell lymphoma and follicular lymphoma was 90.5% and 87.5%, respectively.

CONCLUSION

Volume perfusion CT allows assessment of differences in vascularity of follicular and diffuse large B cell lymphomas, reflecting vascular luminal variability and histopathologic anatomy.

Lymphangiogenesis in non-Hodgkin's lymphoma and its correlation with cyclooxygenase-2 and vascular endothelial growth factor-C

We aimed to investigate the correlations between lymphangiogenesis, cyclooxygenase (COX)-2 and vascular endothelial growth factor-C (VEGF-C) in non-Hodgkin's lymphoma (NHL) and their associations with the clinical parameters of patients. A total of 75 patients diagnosed with NHL were enrolled in this study. Of the 75 patients, 14 (18.7%) had low-grade and 61 (81.3%) had aggressive lymphoma. We examined the immunohistochemical expression of COX-2 and VEGF-C and estimated lymphangiogenesis by counting lymphatic vessels expressing lymph vessel endothelial hyaluronan receptor-1 (LYVE-1). Our results showed that lymphatic vessel density (LVD) was positive in 59.0% of the cases with aggressive morphology, while the LVD positive rate of indolent lymphoma was only 28.6% (P=0.039). Both COX-2 and VEGF-C were correlated with lymphangiogenesis (P=0.030 and 0.000, respectively). The expression levels of COX-2 and VEGF-C were significantly correlated (P=0.015). LVD, COX-2 and VEGF-C were not correlated with the gender, age, lactate dehydrogenase (LDH) levels, β2 microglobulin (β2M) levels, extranodal involvement, disease stage, B symptoms or international prognostic index of the patients. In conclusion, lymphangiogenesis was correlated with aggressive histology in NHL. COX-2 and VEGF-C are inducers of lymphangiogenesis and their expression levels were correlated in NHL.

A phase 2 trial of standard-dose cyclophosphamide, doxorubicin, vincristine, prednisone (CHOP) and rituximab plus bevacizumab for patients with newly diagnosed diffuse large B-cell non-Hodgkin lymphoma: SWOG 0515

S0515 was a phase 2 trial to determine whether the addition of bevacizumab to cyclophosphamide, doxorubicin, vincristine, prednisone (CHOP) plus rituximab (R-CHOP) would improve progression-free survival (PFS) without adding significant toxicity in patients with newly diagnosed advanced diffuse large B-cell lymphoma. A total of 73 patients were enrolled. For the 64 eligible patients, median age was 68 years, and 60% had International Prognostic Index scores more than or equal to 3. The observed 1- and 2-year PFS estimates were 77% and 69%, respectively. These PFS estimates were not statistically different from the expected PFS for this population if treated with R-CHOP alone. Grade 3 or higher toxicities were observed in 81% of patients, including 2 grade 5 events. The majority of serious toxicities were hematologic but also included 5 patients with gastrointestinal perforations, 4 patients with thrombotic events, and 11 patients who developed grade 2 or 3 left ventricular dysfunction. Higher baseline urine VEGF and plasma VCAM levels correlated with worse PFS and overall survival. In conclusion, the addition of bevacizumab to R-CHOP chemotherapy was not promising in terms of PFS and resulted in increased serious toxicities, especially cardiac and gastrointestinal perforations. This study is registered at www.clinicaltrials.gov as #NCT00121199.

Potent antitumor effects of bevacizumab in a microenvironment-dependent human lymphoma mouse model

We established a mouse model of microenvironment-dependent human lymphoma, and assessed the therapeutic potential of bevacizumab, an antitumor agent acting on the microenvironment. NOD/Shi-scid, IL-2Rγ^null (NOG) mice were used as recipients of primary tumor cells from a patient with diffuse large B-cell lymphoma (DLBCL), which engraft and proliferate in a microenvironment-dependent manner. The lymphoma cells could be serially transplanted in NOG mice, but could not be maintained in in vitro cultures. Injection of bevacizumab together with CHOP (cyclophosphamide, doxorubicin, vincristine, prednisolone) significantly increased necrosis and decreased vascularization in the tumor, compared with CHOP alone. Levels of human soluble interleukin-2 receptor (sIL2R) in the serum of bevacizumab+CHOP-treated mice (reflecting the DLBCL tumor burden) were significantly lower than in CHOP recipients. Mice receiving bevacizumab monotherapy also showed significant benefit in terms of tumor necrosis and vascularization, as well as decreased serum sIL2R concentrations. The present DLBCL model reflects the human DLBCL in vivo environment more appropriately than current mouse models using established tumor cell lines. This is the first report to evaluate the efficacy of bevacizumab in such a tumor microenvironment-dependent model. Bevacizumab may be a potential treatment strategy for DLBCL patients.

Angiogenesis in Non-Hodgkin's Lymphoma: An Intercategory Comparison of Microvessel Density

Background. This study was aimed at comparing angiogenesis, seen as microvessel density (MVD) in subtypes of non-Hodgkin's lymphoma (NHL). Methods. In this study, 64 cases of NHL diagnosed over a three-year period were included along with 15 lymph node biopsies of reactive hyperplasia. NHLs were classified using REAL classification, and immunohistochemistry was performed for CD34 in all cases. CD34-stained sections were evaluated for “hot spots,” where MVD was assessed and expressed as per mm². Appropriate statistical methods were applied. Results. There were 6 cases of well-differentiated lymphocytic lymphoma (SLL), 21 diffuse large B-cell lymphoma (DLBCL), 15 follicular lymphoma, 10 lymphoblastic lymphoma, 7 MALToma, and 5 peripheral T-cell lymphoma (PTCL). Mean MVD was highest in reactive hyperplasia (191.92 ± 12.16 per mm²) compared to all NHLs. Among NHLs, PTCL demonstrated the highest MVD (183.42 ± 8.24) followed by DLBCL (149.91 ± 13.68). A significant difference was found in MVD between reactive and individual lymphoma groups. SLL had significantly lower MVD than other lymphoma subtypes. Conclusion. Angiogenesis, assessed by MVD, showed significant differences among subtypes of NHL, especially the indolent types like SLL. The higher MVD in aggressive lymphomas like PTCL and DLBCL can potentially be utilized in targeted therapy with antiangiogenic drugs.

Microenvironment-centred dynamics in aggressive B-cell lymphomas

Aggressive B-cell lymphomas share high proliferative and invasive attitudes and dismal prognosis despite heterogeneous biological features. In the interchained sequence of events leading to cancer progression, neoplastic clone-intrinsic molecular events play a major role. Nevertheless, microenvironment-related cues have progressively come into focus as true determinants for this process. The cancer-associated microenvironment is a complex network of nonneoplastic immune and stromal cells embedded in extracellular components, giving rise to a multifarious crosstalk with neoplastic cells towards the induction of a supportive milieu. The immunological and stromal microenvironments have been classically regarded as essential partners of indolent lymphomas, while considered mainly negligible in the setting of aggressive B-cell lymphomas that, by their nature, are less reliant on external stimuli. By this paper we try to delineate the cardinal microenvironment-centred dynamics exerting an influence over lymphoid clone progression in aggressive B-cell lymphomas.

VEGFA and VEGFR2 genetic polymorphisms and survival in patients with diffuse large B cell lymphoma

We evaluated the impact of functional polymorphisms in the vascular endothelial growth factor A (VEGFA) and vascular endothelial growth factor 2 (VEGFR2) genes on the survival of patients with diffuse large B cell lymphoma (DLBCL). Five potentially functional polymorphisms in the VEGFA (rs699947, rs2010963 and rs3025039) and VEGFR2 (rs1870377 and rs2305948) genes were assessed in 494 DLBCL patients treated with rituximab plus CHOP chemotherapy. The associations of genotype and haplotype with overall survival (OS) and progression-free survival (PFS) were analyzed. Of the five polymorphisms, VEGFR2 rs1870377T>A was significantly associated with both OS and PFS; in the dominant model, patients with the AA + TA genotypes had significantly better OS (P = 0.002) and PFS (P = 0.004) than those with the TT genotype. The association between significantly better OS and the AA + TA genotypes was observed separately in patients with low (0-2; P = 0.035) and high (3-5; P = 0.043) International Prognostic Index scores. Multivariate analysis showed that, relative to the AA + TA genotypes, the TT genotype was an independent prognostic factor for poor OS (HR, 1.71; 95% CI, 1.21-2.43; P = 0.002) and PFS (HR, 1.57; 1.13-2.17; P = 0.004). Other independent significant predictors of survival in patients with DLBCL were International Prognostic Index score, age > 60 years, lactate dehydrogenase concentration >normal, extranodal disease >1 and presence of B symptoms. The VEGFR2 rs1870377 polymorphism might affect survival in patients with DLBCL, suggesting that angiogenesis might be related to poor survival in these patients.

Angioimmunoblastic T-cell lymphoma: the effect of initial treatment and microvascular density in 31 patients

The objectives of this study are to explore the clinical features and treatment outcomes and to investigate the correlation between microvessel density (MVD) and survival in patients with angioimmunoblastic T-cell lymphoma (AITL). We retrospectively analyzed clinical and follow-up data of 31 patients treated in two hospitals during 1995-2009 histologically proven AITL. We also assessed MVD in the lump of 31 previously untreated patients using α-CD34 immunohistochemical staining. The median age of the 31 patients was 48 years, eighty percent of the patients were in an advanced stage. 67.7% of them had B symptoms, with the follow-up of 2-13 years, the 5-year overall survival rate was 25.8%. The response rates (RR) of CHOP group and COP (cyclophosphamide, vincristine and prednisolone) group are 76.5 and 75%, respectively, which is no significant difference (P=0.894). RR did not differ whether chemotherapy regimens contained anthracycline or not. The 3-year PFS rate for patients who received COP and CHOP regimen was 25.4 and 35.3% (P=0.562), while 5-year OS rates were 25.0 and 29.4%, respectively (P=0.667). The median PFS for patients with high MVD and low MVD were 15.1 and 30.0 months (P=0.048), while the median OS were 20 and 45 months, respectively (P=0.038). Patients who were sensitive to initial chemotherapy COP regimen have the similar therapeutic effect to CHOP regimen. Patients with high MVD measured in the microenvironment had worse PFS and OS than AITL patients with low expression.

Strong cross-talk between angiogenesis and EBV: do we need different treatment approaches in lymphoma cases with EBV and/or high angiogenic capacity

Angiogenesis is the new blood vessels formation and is the critical event for the growth of malignant diseases and plays a key role in the development, invasion, and metastasis of malignant tumors. Epstein-Barr virus (EBV) is an important carcinogen causing to the some neoplastic disorders and lytically infected cells may contribute to the growth of EBV-associated malignancies, and this phenomenon is related with enhancing angiogenesis. Due to the strong cross-talk between angiogenesis and viral carcinogenesis and increased information about the angiogenesis and viral carcinogenesis in lymphomas, we need new therapeutic approaches to cases with lymphoma. Due to the strong cross-talk between angiogenesis and viral lymphomagenesis, this association was reviewed in this study.

Involvement of the Syk-mTOR pathway in follicular lymphoma cell invasion and angiogenesis

Follicular lymphoma (FL) is the second-most common non-Hodgkin's lymphoma. The disease affects the lymph nodes, and 50% of patients present with bone marrow infiltration; however, the mechanisms involved in dissemination of the disease are not yet known. We previously reported that FL cells display an overexpression of Syk, a tyrosine kinase involved in many cellular processes including cell migration. Therefore, we sought to explore its role in the invasive process. Here, we show that FL patients display higher matrix metalloproteinase (MMP)-9 and vascular endothelial growth factor (VEGF) levels than healthy donors. Moreover, using Syk small interfering RNA and the Syk inhibitor R406, we demonstrate that, in FL cells, Syk is involved in the regulation of MMP-9 and VEGF expression, and that invasion and angiogenesis is mediated through a phosphatidylinositol-3 kinase (PI3K)-mammalian target of rapamycin module. Finally, using a FL xenograft mouse model we observe that fostamatinib (R788), inhibits MMP-9 expression and angiogenesis in vivo. Altogether, this study provides strong evidence that Syk represents an encouraging therapeutic target in FL and suggests the potential use of fostamatinib as an anti-invasive and anti-angiogenic drug.

CSF1 expression in nongynecological leiomyosarcoma is associated with increased tumor angiogenesis

Leiomyosarcoma (LMS) is a malignant tumor of smooth muscle cells for which few effective therapies exist. A subset of LMS cases express macrophage colony-stimulating factor (CSF1) and the resultant tumor-associated macrophage (TAM) infiltration predicts poor clinical outcome. Further, TAMs have been shown to increase tumor angiogenesis. Here, we analyzed 149 LMS cases by immunohistochemistry for vascular marker CD34 and show that high microvessel density (MVD) in nongynecological LMS cases significantly predicts poor patient outcome. The majority of high MVD cases were also CSF1-positive, and when combining high MVD with CSF1 expression, an even stronger prognostic correlation with patient outcome was obtained. Gene expression profiling revealed that MVD has a stronger correlation with CSF1 expression than with expression of vascular endothelial growth factor isoforms, which have traditionally been used as markers of angiogenesis and as anti-angiogenic therapeutic targets. Finally, patterns of CSF1 expression and TAM recruitment remained consistent between primary tumors and their metastases, and between primary tumors and those grown as xenografts in mice, highlighting the stability of these features to the biology of LMS tumors. Together, these findings suggest an important role for CSF1 and the resulting TAM infiltration in the pathological neovascularization of LMS tumors and provide a rationale for CSF1-targeted therapies in LMS.

Angiogenic markers in canine lymphoma tissues do not predict survival times in chemotherapy treated dogs

Angiogenesis, which is essential for malignancies to progress, depends on various signalling proteins including vascular endothelial growth factor (VEGF) and vascular endothelial growth factor receptors 1 and 2 (VEGFR-1 and VEGFR-2). Microvessel density (MVD) is frequently used to evaluate angiogenesis. This study assessed the relationship between expression of VEGF, VEGFR-1 and VEGFR-2, MVD and the survival time in dogs with lymphoma. VEGF, VEGFR-1 and VEGFR-2 expression was evaluated immunohistochemically and microvessel profiles were counted in 34 lymphoma samples. Seventy-nine percent of the samples showed high VEGF expression and 62% were highly positive for VEGFR-1; VEGFR-2 immunoreactivity was mostly negative. Dogs treated with chemotherapy had a median survival time of 266days, but no significant relationships were found between overall survival time, MVD and expression of VEGF, VEGFR-1 or VEGFR-2. In this study, VEGF its receptors and the MVD were no prognostic factors in dogs with lymphoma.

Image analysis tools for evaluation of microscopic views of immunohistochemically stained specimen in medical research-a review

The aim of this study is to review the methods being used for image analysis of microscopic views of immunohistochemically stained specimen in medical research. The solutions available range from general purpose software to commercial packages. Many studies have developed their own custom written programs based on some general purpose software available. Many groups have reported development of computer aided image analysis programs aiming at obtaining faster, simpler and cheaper solutions. Image analysis tools namely Aperio, Lucia, Metaview, Metamorph, ImageJ, Scion, Adobe Photoshop, Image Pro Plus are also used for evaluation of expressions using immunohistochemical staining. An overview of such methods used for image analysis is provided in this paper. This study concludes that there is good scope for development of freely available software for staining intensity quantification, which a medical researcher could easily use without requiring high level computer skills.

Image analysis tools for evaluation of microscopic views of immunohistochemically stained specimen in medical research-a review

The aim of this study is to review the methods being used for image analysis of microscopic views of immunohistochemically stained specimen in medical research. The solutions available range from general purpose software to commercial packages. Many studies have developed their own custom written programs based on some general purpose software available. Many groups have reported development of computer aided image analysis programs aiming at obtaining faster, simpler and cheaper solutions. Image analysis tools namely Aperio, Lucia, Metaview, Metamorph, ImageJ, Scion, Adobe Photoshop, Image Pro Plus are also used for evaluation of expressions using immunohistochemical staining. An overview of such methods used for image analysis is provided in this paper. This study concludes that there is good scope for development of freely available software for staining intensity quantification, which a medical researcher could easily use without requiring high level computer skills.

Novel antibodies against follicular non-Hodgkin's lymphoma

The anti-CD20 monoclonal antibody rituximab has revolutionized the treatment of patients with follicular B-cell lymphoma. With the combination of chemotherapy and rituximab the overall survival rate has increased with approximately 30%. Unfortunately, there is resistance to rituximab with relapse of the disease in about 60% of the patients during the first five years of treatment and eventually in all patients. To this end, there is a need to develop improved anti-CD20 monoclonal antibodies and antibodies that target other attractive molecules expressed on the follicular lymphoma cell. This review describes the development and clinical achievements so far of next generation anti-CD20 and other antibodies in the treatment of follicular B-cell lymphoma.

Sunitinib in relapsed or refractory diffuse large B-cell lymphoma: a clinical and pharmacodynamic phase II multicenter study of the NCIC Clinical Trials Group

There are limited effective therapies for most patients with relapsed diffuse large B-cell lymphoma (DLBCL). We conducted a phase II trial of the multi-targeted vascular endothelial growth factor receptor (VEGFR) kinase inhibitor, sunitinib, 37.5 mg given orally once daily in adult patients with relapsed or refractory DLBCL. Of 19 enrolled patients, 17 eligible patients were evaluable for toxicity and 15 for response. No objective responses were seen and nine patients achieved stable disease (median duration 3.4 months). As a result, the study was closed at the end of the first stage. Grades 3-4 neutropenia and thrombocytopenia were observed in 29% and 35%, respectively. There was no relationship between change in circulating endothelial cell numbers (CECs) and bidimensional tumor burden over time. Despite some activity in solid tumors, sunitinib showed no evidence of response in relapsed/refractory DLBCL and had greater than expected hematologic toxicity.

Dynamic contrast enhancement magnetic resonance imaging (DCE-MRI) for differential diagnosis in head and neck cancers

PURPOSE

To examine the potential of dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) for differential diagnosis of head and neck cancer.

METHODS AND MATERIALS

DCE-MRI was performed in 26 patients with untreated squamous cell carcinoma (SCC), 28 undifferentiated carcinoma (UD) and 8 lymphoma. DCE-MRI was analyzed with the pharmacokinetic model proposed by Tofts and Kermode to produce the three DCE parameters: k(trans), v(e) and v(p). Areas under the curve (AUC) at the initial 60 and 90s (AUC60 and AUC90) were also recorded. Histogram analysis was conducted to obtain the mean, 25%, 50%, 75% and 95% percentile values and the Kruskal-Wallis test was used to compare the DCE parameters between the three groups of cancer.

RESULTS

k(trans), AUC60 and AUC90 showed significant differences (p<0.01) between UD/SCC and UD/lymphoma, but not between SCC/lymphoma. The mean AUC90 demonstrated the highest accuracy of 78% (sensitivity of 68% and specificity of 88%) for distinguishing UD and SCC, and the 75% percentile AUC90 provided the highest accuracy of 97% (sensitivity of 100% and specificity of 88.5%) for distinguishing UD and lymphoma.

CONCLUSIONS

There are significant differences in the DCE parameters which show the potential for distinguishing UD from SCC or lymphoma.

High-mobility group B1 proteins in canine lymphoma: prognostic value of initial and sequential serum levels in treatment outcome following combination chemotherapy

Elevated high-mobility group box 1 (HMGB1) levels have been demonstrated in different human neoplasias. Information on serum HMGB1 before and during chemotherapy is lacking, as is data pertaining to its prognostic significance. The aim of this study was to characterize serum HMGB1 level in dogs with lymphoma and to assess its influence on the outcome following chemotherapy. Serum HMGB1 concentrations were measured in 16 dogs with lymphoma before treatment (W1) and on weeks 2 (W2), 6 (W6) and 12 (W12) of treatment with chemotherapy. Initial serum HMGB1 levels were significantly higher than HMGB1concentrations in control dogs and the levels in W2, W6 and W12. HMGB1-W1 concentrations were lower in dogs achieving complete remission than that in the single dog with partial remission. The ratio W12/W6 exhibited significant influence on remission duration. In these dogs with lymphoma, serum HMGB1 was elevated in comparison with that in controls. Initial serum HMGB1 level and its modulation during treatment may possess prognostic value.

Role of Wnt canonical pathway in hematological malignancies

Wnt canonical signaling pathway plays a diverse role in embryonic development and maintenance of organs and tissues in adults. It has been observed that Wnt/β-catenin signaling pathway is involved in the pathogenesis of many carcinomas. Moreover, Wnt/β-catenin pathway has been revealed to be associated with angiogenesis. Wnt canonical pathway signaling has great potential as a therapeutic target. It has been disclosed that some hematological malignancies, such as chronic lymphocytic leukemia, mantle cell lymphoma, may occur partly due to the constitutive activation of Wnt canonical signaling pathway. This review will summarize the latest development in Wnt canonical signaling pathway and its roles in tumorigenesis and angiogenesis.

Vascularization predicts overall survival and risk of transformation in follicular lymphoma

Follicular lymphoma patients display heterogeneous overall survival and variable risk of transformation. Recent studies have highlighted the role of the microenvironment. The contribution of microvessel density to follicular lymphoma survival remains controversial. We used a quantitative tumor mapping approach to determine whether the degree of vascularization correlated with outcome in a uniformly treated cohort. Whole-tissue sections of diagnostic biopsies from 84 cases were stained for CD34 and tumor-to-vessel-distance that encompassed 90% of the tumor (TVD(90)) was determined using image analysis. Twenty-one cases with lower TVD(90) showed inferior overall survival (P=0.0001) and high risk of transformation (P=0.01). These cases significantly correlated with increased Lymphoma-Associated Macrophages (χ(2)=0.025). In multivariate analysis macrophages content, IPI and TVD(90) were independent predictors of overall survival (P=0.05, P=0.001 and P=0.01, respectively) and IPI and TVD(90) predicted risk of transformation (P=0.008 and P=0.08, respectively). Increased angiogenesis is an independent marker of inferior survival and may promote transformation.

Clinical impact of bulky mass in the patient with primary extranodal diffuse large B cell lymphoma treated with R-CHOP therapy

Although numerous studies about primary extranodal diffuse large B cell lymphoma (DLBCL) were reported sporadically, the literature of clinical value of immunophenotype and bulky diameter in rituximab era is limited. Ninety-six patients with primary extranodal DLBCL receiving R-CHOP therapy were analyzed to evaluate whether immunophenotype and size of bulky disease are significantly important. The International Prognostic Index was still an important prognostic factor for progression-free survival (PFS) and overall survival (OS; p = 0.003, p = 0.027). Difference of survival between germinal center (GC) type and non-GC type was not different (PFS: p = 0.192; OS: p = 0.197). In two separated groups according to extranodal maximum tumor diameter (EN-MTD) 7.5 cm as cutoff value for survival, the group of EN-MTD > or =7.5 cm had lower PFS and OS than <7.5 cm (PFS: p = 0.001; OS: p = 0.008). In four divided subgroups according to EN-MTD combined with immunophenotype, the subgroup of non-GC type with EN-MTD > or = 7.5 cm had lower PFS and OS compared with the other subgroups (PFS: p < 0.001; OS: p = 0.008). Multivariate analysis revealed that non-GC with EN-MTD > or = 7.5 cm was an independent prognostic parameter (PFS: HR = 5.407, 95%CI = 2.378-12.294, p < 0.001; OS: HR = 4.136, 95%CI = 1.721-9.941, p = 0.002). Bulky primary extranodal DLBCL would be associated with unfavorable outcome especially in non-GC type.