Concordant but not discordant bone marrow involvement in diffuse large B-cell lymphoma predicts a poor clinical outcome independent of the International Prognostic Index

Utility of leukocyte-associated immunoglobulin-like receptor-1 (CD305) in flow cytometric detection of minimal bone marrow involvement by B-cell non-Hodgkin lymphoma

Multicolor flow cytometry (MFC) is crucial in detecting occult or minimal bone marrow (BM) involvement by non-Hodgkin lymphomas (NHL), which may not be detected using trephine biopsy or imaging studies. Detection of low-level BM involvement can be challenging without definite immunophenotypic aberrancies. We studied the utility of CD305 in MFC detection of minimal BM involvement by B-NHL, especially in the absence of aberrancies by commonly used markers. The study included 1084 consecutive BM samples submitted for the staging of B-NHLs (excluding CLL) over two years. Samples were studied for morphological, immunophenotypic, and histopathological assessment. MFC studies were performed using 10-13 color MFC, including CD305-antibody (clone, DX26). Minimal BM involvement was defined with a cutoff of ≤10% lymphoma cells in viable cells on MFC assessment. Of 1084, 148 samples revealed overt morphological involvement by B-NHL and were excluded from analysis. BM samples of 172/936 patients were morphologically negative but revealed involvement using MFC independently. Corresponding trephine biopsy involvement was detected in only 79/172 (45.9%) patients. On MFC, 23/172 samples showed BM involvement with >10% lymphoma cells, and 149/172 (86.6%) samples revealed minimal involvement. In 54/149 (36.24%) samples, lymphoma cells were detected only with aberrant loss of CD305 expression. In 78 of the remaining 95 samples (82.1%), it provided an immunophenotypic aberrancy addition to other markers and supported the results. CD305 is a highly useful marker in the flow cytometric assessment of minimal BM involvement by B-NHL. MFC is a superior modality to trephine biopsy in detecting low-level BM involvement.

Clinical significance of bone marrow involvement by immunoglobulin gene rearrangement in de novo diffuse large B-cell lymphoma: a multicenter retrospective study

Background

Bone marrow (BM) involvement is an indicator of a poor prognosis in diffuse large B-cell lymphoma (DLBCL); however, few studies have evaluated the role of immunoglobulin gene rearrangement (IgR) in detecting BM involvement.

Methods

We evaluated the clinical characteristics and treatment outcomes of patients with DLBCL based on histological BM involvement or positive BM IgR using polymerase chain reaction or next-generation sequencing. We also investigated the role of consolidative upfront autologous hematopoietic stem cell transplantation (ASCT) in patients with DLBCL and BM involvement.

Results

Among 624 patients, 123 (19.7%) with histological BM involvement and 88 (17.5%) with positive IgR in histologically negative BM had more advanced disease characteristics. Overall (OS) and progression-free (PFS) survival was better for patients with negative BM histology and negative IgR than that in patients with histological BM involvement (P = 0.050 and P < 0.001, respectively) and positive IgR with negative BM histology (P = 0.001 and P = 0.005, respectively). Survival rates did not differ among 82 (13.1%) patients who were treated with upfront ASCT and had histological BM involvement or positive IgR with negative BM histology. The survival outcomes were worse for patients who were not treated with upfront ASCT and for those with histological BM involvement or positive IgR, than for those with negative BM histology and negative IgR.

Conclusion

Patients diagnosed with DLBCL and BM involvement based on histology or IgR had aggressive clinical features and poor survival. Upfront ASCT mitigated poor prognosis due to BM involvement.

Identification of Tensin-3 as a MALT1 substrate that controls B cell adhesion and lymphoma dissemination

The protease MALT1 promotes lymphocyte activation and lymphomagenesis by cleaving a limited set of cellular substrates, most of which control gene expression. Here, we identified the integrin-binding scaffold protein Tensin-3 as a MALT1 substrate in activated human B cells. Activated B cells lacking Tensin-3 showed decreased integrin-dependent adhesion but exhibited comparable NF-κB1 and Jun N-terminal kinase transcriptional responses. Cells expressing a noncleavable form of Tensin-3, on the other hand, showed increased adhesion. To test the role of Tensin-3 cleavage in vivo, mice expressing a noncleavable version of Tensin-3 were generated, which showed a partial reduction in the T cell-dependent B cell response. Interestingly, human diffuse large B cell lymphomas and mantle cell lymphomas with constitutive MALT1 activity showed strong constitutive Tensin-3 cleavage and a decrease in uncleaved Tensin-3 levels. Moreover, silencing of Tensin-3 expression in MALT1-driven lymphoma promoted dissemination of xenografted lymphoma cells to the bone marrow and spleen. Thus, MALT1-dependent Tensin-3 cleavage reveals a unique aspect of the function of MALT1, which negatively regulates integrin-dependent B cell adhesion and facilitates metastatic spread of B cell lymphomas.

Lenalidomide overcomes the resistance to third-generation CD19-CAR-T cell therapy in preclinical models of diffuse large B-cell lymphoma

PURPOSE

Chimeric antigen receptor (CAR)-T cells against CD19 have been proven to be effective in treating B-cell hematological malignancies. However, the efficacy of this promising therapy is limited by many factors.

METHODS

In this study, the germinal center B-cell-like diffuse large B-cell lymphoma (GCB-DLBCL) cell line OCI-Ly1, and patient-derived xenografted (PDX) mice (CY-DLBCL) were used as the CAR-T cell-resistant model. Meanwhile, the activated B-cell-like (ABC) DLBCL cell line OCI-Ly3 and PDX mice (ZML-DLBCL) were defined as the CAR-T sensitive model. The enhancement of CAR-T cell function by lenalidomide (LEN) was examined in vitro and in vivo.

RESULTS

Lenalidomide effectively enhanced the function of third-generation CD19-CAR-T cells by polarizing CD8+ CAR-T cells to CD8 early-differentiated stage and Th1 type, reducing CAR-T cell exhaustion and improving cell expansion. It was further demonstrated that CAR-T cells combined with LEN substantially reduce the tumor burden and prolong the survival time in various DLBCL mouse models. LEN was also found to promote the infiltration of CD19-CAR-T cells into the tumor site by modulating the tumor microenvironment.

CONCLUSION

In summary, the results of the present study suggest that LEN can improve the function of CD19-CAR-T cells, providing a basis for clinical trials using this combination therapy against DLBCL.

Multicolor flow cytometric assessment of Ki67 expression and its diagnostic value in mature B-cell neoplasms

Background

There is no unified standard data about the sensitivity and specificity regarding flow cytometry analysis of Ki67 expression during lymphoma diagnoses.

Objective

This evaluated the efficacy of multicolor flow cytometry (MFC) in an estimate of the proliferative activity of B-cell non-Hodgkin lymphoma by comparing the expression of Ki67 using MFC and immunohistochemicals (IHC).

Method

A total of 559 patients with non-Hodgkin B-cell lymphoma were immunophenotyped using sensitive MFC, of which 517 were newly diagnosed and 42 were transformed lymphomas. Test samples include peripheral blood, bone marrow, various body fluids, and tissues. Through MFC multi-marker accurate gating, abnormal mature B lymphocytes with restricted expression of the light chain were screened. Ki67 was added to determine the proliferation index; the positive rate of Ki67 in tumor B cells was evaluated by cell grouping and internal control. For tissue specimens, MFC and IHC analyses were performed simultaneously to assess the Ki67 proliferation index.

Results

The positive rate of Ki67 by MFC was correlated with the subtype and aggressiveness of B-cell lymphoma. Ki67 could distinguish indolent lymphomas from aggressive subtypes with a cut-off value of 21.25%, and differentiate transformation from indolent lymphoma with a cut-off value of 7.65%. The expression of Ki67 by MFC (regardless of the type of samples)was highly agreement with the Ki67 proliferative index of tissue samples assessed by pathologic immunohistochemistry. MFC showed a fairly constant negative bias in evaluating tissue or bone marrow samples, compared with IHC.

Conclusions

Ki67 is a valuable flow marker that can distinguish between indolent and aggressive types of lymphoma and assess whether indolent lymphomas are transformed. Using MFC to evaluate the positive rate of Ki67 is important in clinical settings. MFC has unique advantages in judging the aggressiveness of lymphoma in samples of bone marrow, peripheral blood, pleural and ascites, and cerebrospinal fluid. This is particularly important when tissue samples cannot be obtained, making it an important supplement for pathologic examination.

Diffuse Large B-Cell Lymphoma (DLBCL): Early Patient Management and Emerging Treatment Options

Diffuse large B-cell lymphoma (DLBCL) represents a curable disease with a 60-70% chance of cure with current R-CHOP chemoimmunotherapy. However, 30-40% of patients are refractory or relapsing. Many attempts failed to improve the outcome of DLBCL patients, including the intensification of R-CHOP regimen, consolidation, or maintenance therapy since the introduction of R-CHOP in 2000. Better understanding of both molecular biology of lymphoma cells and the tumor microenvironment raised the hope for future improvement of DLBCL patients' survival. Novel molecular findings have initiated clinical trials exploring targeted therapy based on driver genetic alterations with an intent to improve survival of high-risk subsets of patients. But the preliminary results remain ambiguous. The approach "agnostic" to specific molecular alterations of lymphoma cell includes antibody-drug conjugates (especially polatuzumab vedotin), immunotherapy comprising different antibodies with immunomodulatory effect (tafasitamab, lenalidomide), and T-cell engaging therapy (bispecific antibodies, early use of CAR T-cell). This approach could increase the cure rates and change the current therapeutic paradigm. However, better prognostic stratification, smarter designs of clinical trials, modification of endpoints including the use of ctDNA are needed. This review covers the complexity of DLBCL management.

Challenges Encountered and Pattern-Based Analysis of Bone Marrow Biopsy in Lymphomas: An Institutional Experience

Objective The evaluation of bone marrow (BM) status is an integral part of the initial workup of patients diagnosed with lymphoma as it plays an important role in staging and predicting prognosis in these patients. This article determines the incidence and pattern of BM involvement in lymphoma cases and distinguishes benign from malignant lymphoid aggregates in BM biopsies.

Materials and Methods The study group included 121 cases of Hodgkin and non-Hodgkin lymphomas for which BM biopsies were performed, fixed in acetic acid-zinc formalin solution, decalcified using 10% formic acid, and subjected to hematoxylin and eosin and immunohistochemistry.

Results The overall incidence of BM biopsy involvement in our study was 31.4% (37/118), including 34.7% (35/101) in cases of B cell lymphomas, 25% (2/8) in cases of T cell lymphomas, and no involvement in Hodgkin lymphoma. The predominant histological pattern of BM involvement was diffused (14/37; 37.8%), followed by interstitial (10/37; 27.1%). Five cases revealed benign nonparatrabecular lymphoid aggregates which could be confused with lymphomatous involvement, especially in low grade lymphomas.

Conclusion A careful examination of the BM biopsies along with clinical history, peripheral blood examination, flow cytometry, and immunohistochemistry will help in arriving at the correct diagnosis.

Development and Characterization of 3D Hybrid Spheroids for the Investigation of the Crosstalk Between B-Cell Non-Hodgkin Lymphomas and Mesenchymal Stromal Cells

Purpose

B-cell non-Hodgkin lymphomas (B-NHLs) are the most common lymphoproliferative malignancy. Despite targeted therapies, the bone marrow involvement remains a challenge in treating aggressive B-NHLs, partly due to the protective interactions of lymphoma cells with mesenchymal stromal cells (MSCs). However, data elucidating the relationship between MSCs and B-NHLs are limited and inconclusive due to the lack of reproducible in vitro three-dimensional (3D) models. Here, we developed and described a size-controlled and stable 3D hybrid spheroids of Ri-1 (diffuse large B-cell lymphoma, DLBCL) and RAJI (Burkitt lymphoma, BL) cells with HS-5 fibroblasts to facilitate research on the crosstalk between B-NHL cells and MSCs.

Materials and Methods

We applied the commercially available agarose hydrogel microwells for a fast, low-cost, and reproducible hybrid lymphoma/stromal spheroids formation. Standard histological automated procedures were used for formalin fixation and paraffin embedding (FFPE) of 3D models to produce good quality slides for histopathology and immunohistochemical staining. Next, we tested the effect of the anti-cancer drugs: doxorubicin (DOX) and ibrutinib (IBR) on mono-cultured and co-cultured B-NHLs with the use of alamarBlue and live/dead cell fluorescence based assays to confirm their relevancy for drug testing studies.

Results

We optimized the conditions for B-NHLs spheroid formation in both: a cell line-specific and application-specific manner. Lymphoma cells aggregate into stable spheroids when co-cultured with stromal cells, of which internal architecture was driven by self-organization. Furthermore, we revealed that co-culturing of lymphoma cells with stromal cells significantly reduced IBR-induced apoptosis compared to the 3D mono-culture.

Conclusion

This article provides details for generating 3D B-NHL spheroids for the studies on the lymphoma- stromal cells. This approach makes it suitable to assess in a relevant in vitro model the activity of new therapeutic agents in B-NHLs.

Bone Marrow Lymphoid Niche Adaptation to Mature B Cell Neoplasms

B-cell non-Hodgkin lymphoma (B-NHL) evolution and treatment are complicated by a high prevalence of relapses primarily due to the ability of malignant B cells to interact with tumor-supportive lymph node (LN) and bone marrow (BM) microenvironments. In particular, progressive alterations of BM stromal cells sustain the survival, proliferation, and drug resistance of tumor B cells during diffuse large B-cell lymphoma (DLBCL), follicular lymphoma (FL), and chronic lymphocytic leukemia (CLL). The current review describes how the crosstalk between BM stromal cells and lymphoma tumor cells triggers the establishment of the tumor supportive niche. DLBCL, FL, and CLL display distinct patterns of BM involvement, but in each case tumor-infiltrating stromal cells, corresponding to cancer-associated fibroblasts, exhibit specific phenotypic and functional features promoting the recruitment, adhesion, and survival of tumor cells. Tumor cell-derived extracellular vesicles have been recently proposed as playing a central role in triggering initial induction of tumor-supportive niches, notably within the BM. Finally, the disruption of the BM stroma reprogramming emerges as a promising therapeutic option in B-cell lymphomas. Targeting the crosstalk between BM stromal cells and malignant B cells, either through the inhibition of stroma-derived B-cell growth factors or through the mobilization of clonal B cells outside their supportive BM niche, should in particular be further evaluated as a way to avoid relapses by abrogating resistance niches.

Chimeric antigen receptor (CAR) T-cell therapy for people with relapsed or refractory diffuse large B-cell lymphoma

BACKGROUND

Diffuse large B-cell lymphoma (DLBCL) is an aggressive cancer of the lymphatic system. About 30% to 40% of people with DLBCL experience relapse and 10% are refractory to first-line treatment usually consisting of R-CHOP chemotherapy. Of those eligible for second-line treatment, commonly consisting of salvage chemotherapy followed by autologous stem-cell transplantation (ASCT), around 50% experience relapse. With a median overall survival of less than six to 12 months, the prognosis of individuals who relapse or are refractory (r/r) to advanced lines of treatment or of those who are ineligible for ASCT, is very poor. With the introduction of chimeric antigen receptor (CAR) T-cell therapy, a novel treatment option for these people is available.

OBJECTIVES

To assess the benefits and harms of chimeric antigen receptor (CAR) T-cell therapy for people with relapsed or refractory (r/r) DLBCL.

SEARCH METHODS

An experienced information specialist performed a systematic database search for relevant articles on CENTRAL, MEDLINE and Embase until September 11th, 2020. We also searched trial registries and reference lists of identified studies up to this date. All search results were screened by two authors independently and a third author was involved in case of discrepancies.

SELECTION CRITERIA

We included prospectively planned trials evaluating CAR T-cell therapy for people with r/r DLBCL. We had planned to include randomised controlled trials (RCTs) and we flexibly adapted eligibility criteria to the most reliable study designs available. We excluded studies involving fewer than 10 participants with r/r DLBCL and studies with a proportion of participants with r/r DLBCL below 70%, unless data were reported separately for this subgroup.

DATA COLLECTION AND ANALYSIS

Two review authors extracted data and performed risk of bias ratings independently. A third author was involved in case of disagreements. As our search did not yield any completed RCTs, prospective controlled non-randomised studies of interventions (NRSIs) or prospective observational studies with a control group, we did not meta-analyse data and reported all results narratively. We adopted the GRADE approach to assess the certainty of the evidence for prioritised outcomes.

MAIN RESULTS

We identified 13 eligible uncontrolled studies evaluating a single or multiple arms of CAR T-cell therapies. We also identified 38 ongoing studies, including three RCTs. Ten studies are awaiting classification due to completion with no retrievable results data or insufficient data to justify inclusion. The mean number of participants enrolled, treated with CAR T-cell therapy and evaluated in the included studies were 79 (range 12 to 344; data unavailable for two studies), 61 (range 12 to 294; data unavailable for one study) and 52 (range 11 to 256), respectively. Most studies included people with r/r DLBCL among people with other haematological B-cell malignancies. Participants had received at least a median of three prior treatment lines (data unavailable for four studies), 5% to 50% had undergone ASCT (data unavailable for five studies) and, except for two studies, 3% to 18% had undergone allogenic stem-cell transplantation (data unavailable for eight studies). The overall risk of bias was high for all studies, in particular, due to incomplete follow-up and the absence of blinding. None of the included studies had a control group so that no adequate comparative effect measures could be calculated. The duration of follow-up varied substantially between studies, in particular, for harms. Our certainty in the evidence is very low for all outcomes. Overall survival was reported by eight studies (567 participants). Four studies reported survival rates at 12 months which ranged between 48% and 59%, and one study reported an overall survival rate of 50.5% at 24 months. The evidence is very uncertain about the effect of CAR T-cell therapy on overall survival. Two studies including 294 participants at baseline and 59 participants at the longest follow-up (12 months or 18 months) described improvements of quality of life measured with the EuroQol 5-Dimension 5-Level visual analogue scale (EQ-5D-5L VAS) or Function Assessment of Cancer Therapy-Lymphoma (FACT-Lym). The evidence is very uncertain about the effect of CAR T-cell therapy on quality of life. None of the studies reported treatment-related mortality. Five studies (550 participants) reported the occurrence of adverse events among participants, ranging between 99% and 100% for any grade adverse events and 68% to 98% for adverse events grade ≥ 3. In three studies (253 participants), 56% to 68% of participants experienced serious adverse events, while in one study (28 participants), no serious adverse events occurred. CAR T-cell therapy may increase the risk of adverse events and serious adverse events but the evidence is very uncertain about the exact risk. The occurrence of cytokine release syndrome (CRS) was reported in 11 studies (675 participants) under use of various grading criteria. Five studies reported between 42% and 100% of participants experiencing CRS according to criteria described in Lee 2014. CAR T-cell therapy may increase the risk of CRS but the evidence is very uncertain about the exact risk. Nine studies (575 participants) reported results on progression-free survival, disease-free survival or relapse-free survival. Twelve-month progression-free survival rates were reported by four studies and ranged between 44% and 75%. In one study, relapse-free survival remained at a rate of 64% at both 12 and 18 months. The evidence is very uncertain about the effect of CAR T-cell therapy on progression-free survival. Thirteen studies (620 participants) provided data on complete response rates. At six months, three studies reported complete response rates between 40% and 45%. The evidence is very uncertain about the effect of CAR T-cell therapy on complete response rates.

AUTHORS' CONCLUSIONS

The available evidence on the benefits and harms of CAR T-cell therapy for people with r/r DLBCL is limited, mainly because of the absence of comparative clinical trials. The results we present should be regarded in light of this limitation and conclusions should be drawn very carefully. Due to the uncertainty in the current evidence, a large number of ongoing investigations and a risk of substantial and potentially life-threatening complications requiring supplementary treatment, it is critical to continue evaluating the evidence on this new therapy.

Application of CD54 in diagnosing bone marrow involvement by using flow cytometry in patients with diffuse large B-cell lymphoma

Background

Flow cytometry plays a key role in detecting bone marrow (BM) involvement in patients with diffuse large B-cell lymphoma (DLBCL). To improve its detection sensitivity, we need to explore novel markers. In this study, we detected the expression CD54 on lymphoma cells in BM specimens from DLBCL patients and clarified its diagnostic significance in BM involvement by DLBCL.

Methods

We collected BM specimens from 76 patients with DLBCL (germinal center B-cell (GCB) = 25, non-GCB = 51) and 10 control patients without lymphoma. We detected and compared the expression of CD54 on lymphoma cells and normal mature B cells by using 10-color panels.

Results

Normal plasma cells expressed a higher level of CD54 as compared with hematogones (p < 0.05) and normal mature B cells (p < 0.05). Among 76 patients, 23 of them (GCB = 12, non-GCB = 11) had BM involvement. Lymphoma B cells from 12 cases (GBC = 4, non-GCB = 8) expressed a higher level of CD54 compared to normal mature B cells (p < 0.05). Additionally, lymphoma cells of the non-GCB subtype frequently expressed a higher level of CD54 in comparison to the GCB subtype (p < 0.05). And the high expression of CD54 was not related to plasmacytoid differentiation.

Conclusion

Aberrant expression of CD54 on lymphoma cells is frequently seen in patients’ BM specimens involved by DLBCL, especially in the non-GCB subtype. CD54 could be used as a new marker to gate on lymphoma cells and improve the detection sensitivity of BM involvement in patients with DLBCL.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08753-0.

Histopathologic and Machine Deep Learning Criteria to Predict Lymphoma Transformation in Bone Marrow Biopsies

CONTEXT.—

Large-cell transformation (LCT) of indolent B-cell lymphomas, such as follicular lymphoma (FL) and chronic lymphocytic leukemia (CLL), signals a worse prognosis, at which point aggressive chemotherapy is initiated. Although LCT is relatively straightforward to diagnose in lymph nodes, a marrow biopsy is often obtained first given its ease of procedure, low cost, and low morbidity. However, consensus criteria for LCT in bone marrow have not been established.

OBJECTIVE.—

To study the accuracy and reproducibility of a trained convolutional neural network in identifying LCT, in light of promising machine learning tools that may introduce greater objectivity to morphologic analysis.

DESIGN.—

We retrospectively identified patients who had a diagnosis of FL or CLL who had undergone bone marrow biopsy for the clinical question of LCT. We scored morphologic criteria and correlated results with clinical disease progression. In addition, whole slide scans were annotated into patches to train convolutional neural networks to discriminate between small and large tumor cells and to predict the patient's probability of transformation.

RESULTS.—

Using morphologic examination, the proportion of large lymphoma cells (≥10% in FL and ≥30% in CLL), chromatin pattern, distinct nucleoli, and proliferation index were significantly correlated with LCT in FL and CLL. Compared to pathologist-derived estimates, machine generated quantification demonstrated better reproducibility and stronger correlation with final outcome data.

CONCLUSIONS.—

These histologic findings may serve as indications of LCT in bone marrow biopsies. The pathologist-augmented with machine system appeared to be the most predictive, arguing for greater efforts to validate and implement these tools to further enhance physician practice.

The value of bone marrow biopsy for staging of patients with primary CNS lymphoma

BACKGROUND

In patients with presumed primary CNS lymphoma (PCNSL) a systemic manifestation is found only in a small minority. Although bone marrow biopsy (BMB) is recommended for staging, its diagnostic value is unclear.

METHODS

A retrospective analysis of 392 patients with presumed PCNSL from three university hospitals and 33 patients with secondary CNS lymphoma (SCNSL) and initial CNS involvement from a multicentre Germany-wide prospective registry was performed.

RESULTS

A BMB was performed and documented in 320/392 patients with presumed PCNSL; 23 had pathologic results. One harboured the same lymphoma in the brain and bone marrow (BM), 22 showed findings in BM discordant to the histology of brain lymphoma; n=12 harboured a low grade lymphoma in the bone marrow, the other showed B-cell proliferation but no proof of lymphoma (n=5), monoclonal B-cells (n=3) or abnormalities not B-cell associated (n=2). In the group of SCNSL with initial CNS manifestation 32/33 patients underwent BMB; seven were documented with bone marrow involvement (BMI); one had concordant results in the brain and bone marrow with no other systemic manifestation. Six had additional systemic lymphoma manifestations apart from the brain and bone marrow.

CONCLUSIONS

In only two out of 352 (0.6%) patients with CNS lymphoma (320 presumed PCNSL and 32 SCNSL) BMB had an impact on diagnosis and treatment. While collected in a selected cohort these findings challenge the value of BMB as part of routine staging in presumed PCNSL.

Prognostic significance of bone marrow 2-[18F]-fluoro-2-deoxy-d-glucose uptake in diffuse large B-cell lymphoma: relation to iliac crest biopsy results

AIM

To investigate the prognostic significance of bone marrow (BM) 2-[¹⁸F]-fluoro-2-deoxy-d-glucose (FDG) uptake in relation to posterior iliac crest BM biopsy (BMB) results in diffuse large B-cell lymphoma (DLBCL).

MATERIALS AND METHODS

Pretreatment integrated positron-emission tomography(PET)/computed tomography (CT) images of 512 DLBCL patients who underwent BMB and received rituximab combined with cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) chemotherapy were analysed retrospectively. BM uptake was assessed visually and by maximum standard uptake value (SUVmax). Associations with lymphoma-specific survival (LSS) were assessed using Kaplan-Meier and Cox regression analyses.

RESULTS

FDG(+) BM was observed in 64 cases (41 focal, 12 heterogeneous, 11 diffuse). This finding distinguished iliac crest involvement (positive in 59 and negative in 453) with 89.6% accuracy (459/512) and 93.6% specificity (424/453). In BMB(+) patients, BM-to-liver SUVmax ratio >1.8 concurred perfectly with FDG(+) BM. During 52 months of follow-up, there were 156 lymphoma-related deaths. In the entire population, multivariate analysis revealed high International Prognostic Index (IPI; p<0.001), old age (p=0.003), bulky disease (p=0.011), BMB(+) (p=0.028), and FDG(+) BM (p=0.019) as independent predictors of worse LSS. In the BMB(+) subgroup, high National Comprehensive Cancer Network-revised IPI (NCCN-IPI; p=0.029) and FDG(+) BM (p=0.008) were significant independent predictors. Among BMB(+) patients with low to low-intermediate NCCN-IPI, FDG(+) BM was associated with significantly worse 2-year LSS (33.3% versus 100%; p=0.017). The same was true among those with high-intermediate NCCN-IPI (34.7% versus 76.9%.; p=0.026).

CONCLUSION

Increased BM FDG in DLBCL is a predictor of worse LSS independent of BMB results and other prognostic variables including IPI/NCCN-IPI.

Evaluation of the prognostic utility of bone marrow biopsy in diffuse large B-Cell lymphoma in the SEER-Medicare dataset

Positron emission tomography-computed tomography (PET-CT) has become the primary modality for staging in diffuse large B-cell lymphoma (DLBCL), whereas the role of staging bone marrow biopsy (BMB) has become less clear. In this analysis, we included 7,005 DLBCL patients in SEER-Medicare who received either PET-CT without BMB (PET-CT w/o BMB), CT with BMB (CT w/ BMB), or both PET-CT and BMB (PET-CT w/ BMB). The proportion of patients undergoing PET-CT increased across years of diagnosis, while the proportion undergoing CT or BMB decreased. In a fully adjusted Cox proportional hazards model, PET-CT w/ BMB was associated with a marginally superior OS compared to PET-CT w/o BMB. Notably, the association between PET-CT w/ BMB and OS was strongest in patients ≤70 years, but was not present when looking at individual stage of diagnosis. Overall, these data do not provide sufficient support to eliminate staging BMB in patients who undergo PET-CT.

Biopsy remains indispensable for evaluating bone marrow involvement in DLBCL patients despite the use of positron emission tomography

Initial staging by positron emission tomography/computed tomography (PET/CT) scanning is recommended for patients with diffuse large B-cell lymphoma (DLBCL). Whether both PET/CT and bone marrow biopsy (BMB) are required remains unclear. This study examined whether staging by PET/CT is sufficient. Participants with untreated DLBCL assessed using both PET/CT and BMB were included. Patients received independent diagnostic assessments from a radiologist and a hematopathologist. Both hematoxylin-eosin staining and CD20 immunostaining were performed to determine the bone marrow involvement in BMB. A total of 84 patients were included. The number of patients with positive bone marrow involvement identified by PET/CT and BMB was 16 (19%) and 22 (26%), respectively. Eight (10%) patients showed positive results in both tests. When considering BMB as a reference, PET/CT showed 36% sensitivity and 87% specificity, with positive and negative predictive values of 50% and 79%, respectively. BMB-positive patients had shorter progression-free (PFS) and overall (OS) survival than their BMB-negative counterparts. Compared to PET/CT-negative patients, patients with positive results did not show any significant differences in PFS and OS. However, among 16 PET/CT-positive patients, poor PFS and OS were observed among patients who were also BMB positive. BMB remains a mandatory step in staging of untreated DLBCL patients.

Comparison of Bone Marrow Involvement with Bone Marrow Biopsy and PET-CT and Evaluation of Any Effects on Survival in Patients Diagnosed with Hodgkin and Non-Hodgkin Lymphoma

We aimed to demonstrate whether PET-CT can replace bone marrow biopsy in detecting bone marrow involvement in subtypes of lymphoma. In addition, we aimed to also reveal whether there is a difference between the mean survival of patients with bone marrow involvement via PET-CT or biopsy. A total of 276 newly diagnosed lymphoma patients who underwent bone marrow biopsy and PET-CT prior to the treatment were scanned retrospectively. Bone marrow biopsy was used as the standard method to investigate the presence of bone marrow involvement in PET-CT. The relationship between bone marrow involvement and mean survival was compared using both methods. Out of the 276 patients, bone marrow involvement was detected with PET-CT and with biopsy, respectively in 56 patients (20.2%) and in 78 patients (28.2%). In terms of PET-CT's accuracy with respect to revealing bone marrow involvement, the highest rates were achieved respectively in diffuse large B cell lymphoma (DLBCL) (87.4%) and Hodgkin lymphoma (HL) (77.7%). In both the PET-CT and bone marrow biopsy methods, Overall Survival (OS) was found to be significantly shorter in patients with involvement than in patients without involvement (P: 0.001). PET-CT may replace bone marrow (BM) biopsy in detecting the bone marrow involvement in aggressive lymphoma subtypes such as DLBCL and HL. The presence of BM involvement at the time of diagnosis in both PET-CT and BM biopsy is associated with poor prognosis, and OS is short in this group.

Systematic review of staging bone marrow involvement in B cell lymphoma by flow cytometry

The clinical relevance of flow cytometry (FC)-based bone marrow involvement (BMI) in B cell non-Hodgkin lymphoma (B-NHL) is not well established. We conducted a systematic review of MEDLINE regarding the use of FC to establish BMI in B-NHL to determine the prevalence of BMI by FC, to understand the interrelation between FC and bone marrow biopsy (BMB), and to explore the prognostic impact of BMI by FC. Relevant exclusion criteria included publication before 2010. Eleven publications (of 18 screened) were included, with 2803 patients involved. Relevant methodological details were often unreported. The prevalence of BMI by FC varied based on histological subtypes included. The median kappa agreement between BMB and FC was 0.68 and the type of discordance (FC+/BMB- vs. FC-/BMB+) was highly variable across studies. Only 4 studies (all in diffuse large B cell lymphoma) assessed the prognostic impact of BMI by FC. Two found a worse prognosis for patients with FC+/BMB- than those without BMI. To conclude, studies assessing BMI by FC are retrospective, of low methodological quality and with heterogeneous findings.

The Role of Integrated Positron Emission Tomography/Computed Tomography (PET/CT) and Bone Marrow Examination in Staging Large B-Cell Lymphoma

Introduction:

In the era of routine use of positron emission tomography/computed tomography (PET/CT) for staging, it is not yet clear whether PET/CT can replace bone marrow biopsy for the assessment of bone marrow involvement in large B-cell lymphoma.

Objectives:

To compare the clinical utility of bone marrow biopsy and PET/CT scanning in the staging of large B-cell lymphoma.

Methods:

This was a retrospective analysis of all patients who presented to single center over a 4-year period with large B-cell lymphoma who had concurrent PET/CT and bone marrow biopsy performed in the assessment and staging of the lymphoma.

Results:

Out of 89 patients, 24 had bone marrow involvement either by PET/CT, by bone marrow biopsy, or by both. Bone marrow biopsy identified 12 patients (sensitivity 50%, specificity 100%, negative predictive value 84%), whereas PET/CT identified 23 patients (sensitivity 96%, specificity 100%, negative predictive value 98%). No patients were upstaged by the bone marrow biopsy result, and no patients had their treatment plan changed based on the bone marrow biopsy result.

Conclusion:

The results show that PET-CT is more sensitive and has better negative predictive value than bone marrow biopsy. This suggests that PET-CT could replace bone marrow biopsy in detecting bone marrow involvement for staging of large B-cell lymphoma.

Impact of bone marrow involvement on outcome in relapsed and refractory transplant eligible diffuse large B-cell lymphoma and transformed indolent lymphoma

In front-line treatment of diffuse large B-cell lymphoma (DLBCL), prior studies suggest that concordant but not discordant involvement of the bone marrow (BM) portends a poor prognosis. The prognostic impact of bone marrow infiltration (BMI) in recurrent or refractory DLBCL (r/rDLBCL) and transformed indolent lymphoma (r/rTRIL) patients is less clear. Thus, we examined the prognostic significance of the infiltration of bone marrow (BMI) by concordant, large B-cells (conBMI) and discordant, small B-cells (disBMI) in this patient group. We performed a single center retrospective analysis of the prognostic impact of BMI diagnosed before start of second-line treatment as well as multiple clinicopathologic variables in 82 patients with r/rDLBCL or r/rTRIL intended to treat with autologous SCT. Twenty-five of 82 patients (30.5%) had BMI. Out of these, 19 (76%) had conBMI and 6 (24%) had disBMI. In patients with conBMI but not disBMI, uni- and multivariate analysis revealed inferior progression free survival (PFS) and overall survival (OS) compared to patients without BMI (median PFS, 9.2 vs 17.45 months, log rank: p = 0.049; Hazard Ratio, 2.34 (Confidence Interval, 1.24-4.44), p = 0.009; median OS 14.72 vs 28.91 months, log rank: p = 0.017; Hazard Ratio, 2.76 (Confidence Interval, 1.43-5.31), p = 0.002). ConBMI was strongly associated with nonGCB subtype as classified by the Hans algorithm (82.4% vs 17.6%, p = 0.01). ConBMI comprised an independent predictor of poor prognosis in primary and secondary r/rDLBCL. Incorporating conBMI in the pretherapeutic risk assessment for r/rDLBCL and r/rTRIL patients may be useful for prognostication, for stratification in clinical trials, and to assess new therapies for this high-risk patient subset that might not benefit from SCT in second-line treatment.

Large B-cell lymphoma presenting primarily in bone marrow is frequently associated with haemophagocytic lymphohistiocytosis and has distinct cytogenetic features

The criteria for primary bone marrow large B-cell lymphoma (PBMLBCL) have not yet been clearly established. We aimed to investigate the clinicopathological features of PBMLBCLs (27 cases) and large B-cell lymphomas (LBCLs) with secondary marrow involvement (55 cases). PBMLBCL was defined as LBCLs presenting initially in bone marrow without lymphadenopathy, extramedullary tumour or localised bone tumour, and no evidence of transformation from low grade B-cell lymphoma. Compared with the patients in the secondary group, more patients in the primary group had haemophagocytic lymphohistiocytosis, cytogenetic aberrations, cytopenias, and atypical lymphocytes in peripheral blood. The most common chromosome abnormality in both groups was 6q deletion. The primary group had additional chromosome 10, 2, and 3 abnormalities. The acquired chromosome 10 aberration was associated with the risk of haemophagocytic lymphohistiocytosis. The 1-year survival rate was lower in the primary group than in the secondary group; however, the difference was not significant when the cases without chemotherapy plus rituximab were excluded. Moreover, multivariate analysis revealed that relatively high white blood cell count, not receiving chemotherapy plus rituximab, and cytogenetic aberrations were poor prognostic factors in the secondary group, but only not receiving chemotherapy plus rituximab was retained in the primary group. In conclusion, PBMLBCL is genetically and clinically distinct. Although patients with PBMLBCL generally have a poor outcome, the disease is treatable and some patients become long-term survivors.

Impact of concurrent indolent lymphoma on the clinical outcome of newly diagnosed diffuse large B-cell lymphoma

Some patients with diffuse large B-cell lymphoma (DLBCL) present with a concurrent indolent lymphoma at diagnosis. Their outcomes in the rituximab era are not fully defined. Using a prospectively followed cohort of 1324 newly diagnosed DLBCL patients treated with immunochemotherapy, we defined the prevalence, characteristics, and outcome of DLBCL with concurrent indolent lymphoma. Compared with patients with DLBCL alone (n = 1153; 87.1%), patients with concurrent DLBCL and follicular lymphoma (FL) (n = 109; 8.2%) had fewer elevations in lactate dehydrogenase, lower International Prognostic Index (IPI), and predominantly germinal center B-cell-like (GCB) subtype, whereas patients with concurrent DLBCL and other indolent lymphomas (n = 62; 4.7%) had more stage III-IV disease and a trend toward higher IPI and non-GCB subtype. After adjusting for IPI, patients with concurrent DLBCL and FL had similar event-free survival (EFS) (hazard ratio [HR] = 0.95) and a trend of better overall survival (OS) (HR = 0.75) compared with patients with DLBCL alone, but nearly identical EFS (HR = 1.00) and OS (HR = 0.84) compared with patients with GCB DLBCL alone. Patients with concurrent DLBCL and other indolent lymphomas had similar EFS (HR = 1.19) and OS (HR = 1.09) compared with patients with DLBCL alone. In conclusion, DLBCL patients with concurrent FL predominantly had the GCB subtype with outcomes similar to that of GCB DLBCL patients. DLBCL patients with concurrent other indolent lymphoma had similar outcomes compared with patients with DLBCL alone. These patients should not be summarily excluded from DLBCL clinical trials.

Impact and Intricacies of Bone Marrow Microenvironment in B-cell Lymphomas: From Biology to Therapy

Lymphoma, a group of widely prevalent hematological malignancies of lymphocyte origin, has become the focus of significant clinical research due to their high propensity for refractory/relapsed (R/R) disease, leading to poor prognostic outcomes. The complex molecular circuitry in lymphomas, especially in the aggressive phenotypes, has made it difficult to find a therapeutic option that can salvage R/R disease. Furthermore, the association of lymphomas with the Bone Marrow (BM) microenvironment has been found to portend worse outcomes in terms of heightened chances of relapse and acquired resistance to chemotherapy. This review assesses the current therapy options in three distinct types of lymphomas: diffuse large B-cell lymphoma, follicular lymphoma and mantle cell lymphoma. It also explores the role of the BM tumor microenvironment as a secure 'niche' for lymphoma cells to grow, proliferate and survive. It further evaluates potential mechanisms through which the tumor cells can establish molecular connections with the BM cells to provide pro-tumor benefits, and discusses putative therapeutic strategies for disrupting the BM-lymphoma cell communication.

Prognostic Value of Bone Marrow F-18 FDG Uptake in Patients with Advanced-Stage Diffuse Large B-Cell Lymphoma

Purpose

We assessed prognostic implication of bone marrow uptake on baseline F-18 fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) in patients with advanced-stage diffuse large B-cell lymphoma (DLBCL).

Methods

We retrospectively reviewed 140 patients with stage III and IV DLBCL, who underwent baseline F-18 FDG PET/CT at diagnosis. Bone marrow uptake on F-18 FDG PET/CT (BM FDG) was compared with findings on bone marrow biopsy (BMB), and patients were grouped based on these results: BMB-positive and BM FDG-positive (group 1), BMB-positive and BM FDG-negative (group 2), BMB-negative and BM FDG-positive (group 3), and BMB-negative and BM FDG-negative (group 4). The prognostic value of clinicopathologic factors and BM FDG for predicting progression-free survival (PFS) and overall survival (OS) was assessed using a Cox proportional hazards model. Differences in PFS and OS were examined by the Kaplan-Meier method.

Results

BMB was the only significant indicator in predicting PFS, and age, IPI score higher than 3, and BM FDG significantly predicted OS. Group 1 showed inferior PFS than group 2 (median PFS, 7.4 vs. 13.9 months; p = 0.04). In contrast, there was no significant difference either in PFS or OS between group 2 and group 3.

Conclusion

We showed that BM FDG-positive predicted a poorer survival in patients with advanced stage DBLCL. We also found that BMB-negative and BM FDG-positive patients had similar PFS or OS to BMB-positive and BM FDG-negative patients. Further study in a larger population is needed to clarify clinical significance of BM FDG in these patients.

Prognostic impact of germinal center B-cell-like and non-germinal center B-cell-like subtypes of bone marrow involvement in patients with diffuse large B-cell lymphoma treated with R-CHOP

The prognostic significances of the germinal center B-cell-like (GCB) and non-germinal center B-cell-like (non-GCB) types of diffuse large B-cell lymphoma (DLBCL) have been reported to be different. We analyzed the effect of the cell of origin (COO) of bone marrow (BM) involvement in patients with DLBCL who were treated with rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) in a single institute.The subtype of BM involvement was evaluated in 633 patients who were diagnosed with primary DLBCL and had been treated with R-CHOP. BM trephine biopsies were analyzed, and immunohistochemical staining of CD20, CD79a, and CD3 was performed. Additional staining of CD10, Bcl-6, and MUM1 was performed to determine the COO based on a previously reported algorithm.BM involvement was present in 81 patients (12.8%). Among them, 30 patients (37.0%) had GCB-type BM involvement and 51 (63.0%) showed non-GCB-type involvement. Kaplan-Meier survival analysis showed that the non-GCB type had the worst progression-free survival (PFS) and overall survival (OS) (P <.001). In multivariate analysis controlled for the International Prognostic Index (IPI) score, non-GCB type was an independent predictor of PFS (P <.004) and OS (P =.042), whereas GCB type was not a prognostic factor independent of the IPI score.Further prognostication based on the COO of BM involvement is a useful indicator of PFS, independent of IPI score. Accurate staging based on the COO should be included in the examination of BM in DLBCL.

Trends in Bone Marrow Sampling and Core Biopsy Specimen Adequacy in the United States and Canada: A Multicenter Study

OBJECTIVES

To assess bone marrow (BM) sampling in academic medical centers.

METHODS

Data from 6,374 BM samples obtained in 32 centers in 2001 and 2011, including core length (CL), were analyzed.

RESULTS

BM included a biopsy (BMB; 93%) specimen, aspirate (BMA; 92%) specimen, or both (83%). The median (SD) CL was 12 (8.5) mm, and evaluable marrow was 9 (7.6) mm. Tissue contraction due to processing was 15%. BMB specimens were longer in adults younger than 60 years, men, and bilateral, staging, and baseline samples. Only 4% of BMB and 2% of BMB/BMA samples were deemed inadequate for diagnosis. BM for plasma cell dyscrasias, nonphysician operators, and ancillary studies usage increased, while bilateral sampling decreased over the decade. BM-related quality assurance programs are infrequent.

CONCLUSIONS

CL is shorter than recommended and varies with patient age and sex, clinical circumstances, and center experience. While pathologists render diagnoses on most cases irrespective of CL, BMB yield improvement is desirable.

Prognostication of diffuse large B-cell lymphoma in the molecular era: moving beyond the IPI

Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous disease with variable outcomes. Despite the majority of patients being cured with combination chemoimmunotherapy, up to 30% eventually succumb to the disease. Until recently, baseline prognostic assessment has centred on the International Prognostic Index (IPI), although this index is yet to impact strongly on treatment choice. Molecular features such as cell of origin, MYC and BCL-2 genetic alterations and protein overexpression were identified over a decade ago, yet their prognostic value is still not fully elucidated. Adding complexity are the plethora of new clinical, biological and molecular prognostic markers described in the recent literature, most of which lack independent validation, likely act as surrogate markers for those already in common use and have yet to substantially impact on therapeutic decision making. This review comprehensively assesses the value of individual prognostic markers in the clinical setting and their potential to predict response to novel agents, and ways to optimise their use in future research.

Mutations or copy number losses of CD58 and TP53 genes in diffuse large B cell lymphoma are independent unfavorable prognostic factors

The advent of next generation sequencing (NGS) technologies has expedited the discovery of novel genetic lesions in DLBCL. The prognostic significance of these identified gene mutations is largely unknown. In this study, we performed NGS for the 27 genes most frequently implicated in 196 patients. Interestingly, TP53 mutations were found to be significantly more common in DLBCL with MYC translocations (r = 0.446, P = 0.034). While no gene mutation was found to be more prevalent in patients with DLBCL with bone marrow involvement, MYD88 mutations were more common in primary DLBCL of the CNS or testis. To evaluate the prognostic significance of the abnormalities of these 27 genes, a total of 165 patients with newly diagnosed DLBCL, NOS were included in a multivariate survival analysis. Surprisingly, in addition to the TP53 mutation, CD58 mutation was found to predict poor clinical outcome. Furthermore, copy number loss of CD58 or TP53 was also identified to be an independent negative prognostic factor. Our results have uncovered the previously unknown critical impact of gene mutations on the prognosis of DLBCL and are fundamentally important for the future design of tailored therapy for improved clinical outcomes.

The utility of bone marrow sampling in the diagnosis and staging of lymphoma in South Africa

INTRODUCTION

The bone marrow biopsy (BMB) is a diagnostic and staging tool in lymphoma that remains practically useful and relevant in resource-constrained settings, despite restricted applications in international staging guidelines, which favour less invasive nuclear medicine techniques.

METHODS

Retrospective laboratory data review of BMBs in adult lymphoma patients from 2005 to 2010 to determine subtypes, rates of bone marrow involvement (BMI), human immunodeficiency virus (HIV) seroprevalence and CD4 counts, trephine length and additional findings.

RESULTS

A total of 1215 BMBs reported in lymphoma included 759 newly diagnosed patients, with BMI in 43.6% of non-Hodgkin lymphoma (NHL) overall, 28.9% of high-grade B subtypes and 35.7% of Hodgkin lymphoma (HL). HIV seroprevalence was 38.8%, 53.0% and 33.9% in the 3 respective groups. There was a statistical association between BMI and HIV seropositivity in Burkitt lymphoma and HL, and BMI and CD4 count in HIV-related HL. Over 10% (n = 79) of new lymphoma cases were diagnosed by BMB with ancillary tests. Occasional histological discordance and transformation were reported in NHL. Focal/unilateral BMI was uncommon. Bilateral BMB and biopsy length exceeding 26 mm did not improve BMI detection.

CONCLUSION

In the South African public sector, high HIV prevalence leads to a different lymphoma pathology profile from the developed world. High BMI rates are encountered. Here, and in similar resource-constrained settings, international lymphoma staging guidelines can be logistically challenging and unaffordable. BMB remains useful in the staging and diagnosis of lymphoma. Unilateral sampling with a processed trephine length of at least 26 mm is recommended.

Clinical impact of CD5 expression in Korean patients with diffuse large B-cell lymphoma

BACKGROUND

CD5-positive diffuse large B-cell lymphoma (CD5+ DLBCL) accounts for 5-10% of DLBCL cases and has poor patient outcomes. However, most studies on CD5+ DLBCL were performed in Japanese patients and only few data are available for Korean population. In this study, we investigated the clinical characteristics and prognostic impact of CD5 expression in Korean patients with bone marrow (BM) involvement of DLBCL.

METHODS

Patients who were initially diagnosed with BM involvement of de novo DLBCL from 2005 to 2013 were included. Clinicopathological features and outcomes of patients were compared between CD5+ and CD5 negative (CD5-) DLBCL.

RESULTS

Among a total of 57 patients, the number of patients with CD5+ and CD5- DLBCL were 13 and 44, respectively. Clinical and laboratory features of CD5+ DLBCL were not significantly different from those of CD5- DLBCL. The 3-year overall survival (OS) rates for CD5+ and CD5- DLBCL were 20.2% and 59.0%, respectively (P=0.031), and 3-year progression-free survival (PFS) rates for CD5+ and CD5- DLBCL were 23.1% and 50.1%, respectively (P=0.055).

CONCLUSION

CD5+ DLBCL with BM involvement showed an inferior survival tendency compared to CD5- DLBCL, and thorough evaluation of CD5 expression might be helpful to predict the prognosis of patients with DLBCL.

Bone Marrow-Liver-Spleen Type of Large B-Cell Lymphoma Associated with Hemophagocytic Syndrome: A Rare Aggressive Extranodal Lymphoma

Recently, an unusual subtype of large B-cell lymphoma (LBCL) with distinctive clinicopathologic features has been recognized; it is characterized by involvement of bone marrow with or without liver and/or spleen, but no lymph node or other extranodal sites, usually associated with fever, anemia, and hemophagocytic lymphohistiocytosis (HLH). Because of this distinctive clinical presentation, it has been designated "bone marrow-liver-spleen" (BLS) type of LBCL. To date there is only one series of 11 cases of BLS type of LBCL with detailed clinical, pathologic, and cytogenetic data. Herein, we describe a case of BLS type LBCL presenting with associated HLH in a 73-year-old female. The bone marrow core biopsy showed cytologically atypical large lymphoma cells present in a scattered interstitial distribution and hemophagocytosis and infrequent large lymphoma cells were seen in the bone marrow aspirate smears. Circulating lymphoma cells were not seen in the peripheral blood smears. The patient underwent treatment with chemotherapy (R-CHOP) but unfortunately passed away 2 months after initial presentation. BLS type of LBCL is a very rare and clinically aggressive lymphoma whose identification may be delayed by clinicians and hematopathologists due to its unusual clinical presentation and pathologic features.

Concordant bone marrow involvement of diffuse large B-cell lymphoma represents a distinct clinical and biological entity in the era of immunotherapy

In diffuse large B-cell lymphoma (DLBCL), the clinical and biological significance of concordant and discordant bone marrow (BM) involvement have not been well investigated. We evaluated 712 de novo DLBCL patients with front-line rituximab-containing treatment, including 263 patients with positive and 449 with negative BM status. Compared with negative BM disease, concordant BM adversely impacted overall and progression-free survival, independent of the International Prognostic Index (IPI) and cell-of-origin classification. Once BM is concordantly involved, poor prognosis was not associated with the extent of BM involvement. Conversely, patients with discordant BM showed favorable overall survival similar to stage I-II DLBCL. A BM-adjusted IPI, using three parameters: concordant BM involvement, age >60 years, and performance status >1, improves the risk stratification for DLBCL with positive BM. Intensive immunochemotherapy seemingly rendered survival benefit for patients with concordant BM, as did rituximab maintenance for the discordant BM group. Frequently revealing adverse clinical and molecular characteristics, patients with concordant BM demonstrated gene expression signatures relevant to tumor cell proliferation, migration and immune escape. In conclusion, clinical and biological heterogeneity is seen in DLBCL with positive BM but concordant BM involvement represents a distinct subset with unfavorable gene signatures, high-risk clinicopathologic features and poor prognosis.

Utility of Bone Marrow Biopsy and Aspirate for Staging of Diffuse Large B Cell Lymphoma in the Era of Positron Emission Tomography With 2-Deoxy-2-[Fluorine-18]fluoro-deoxyglucose Integrated With Computed Tomography

BACKGROUND

About one-third of patients with diffuse large B cell lymphoma (DLBCL) have lymphomatous bone marrow involvement (BMI) at the time of diagnosis, and bone marrow aspirate/biopsy (BMAB) is considered the gold standard to detect such involvement. [¹⁸F] fluorodeoxyglucose positron emission tomography combined with computed tomography (PET-CT), has become standard pretreatment imaging in DLBCL and may be a noninvasive alternative to BMAB to ascertain BMI. Prior studies have suggested that PET-CT scan may obviate the need for BMAB as a component for staging patients with newly diagnosed DLBCL, but this is not yet a standard of practice. The aim of this retrospective study was to determine the accuracy of PET-CT in detecting BMI in DLBCL and to define 2-year and 5-year overall survival based on BMI by BMAB versus PET-CT.

METHODS

We reviewed institutional records of all patients with newly diagnosed DLBCL between January 2004 and December 2013 who underwent pretreatment PET-CT and BMAB. PET-CT images were visually assessed for BMI, including the posterior iliac crest. Patients with primary mediastinal DLBCL, previous history or coexistence of another lymphoma subtype, and those with a nondiagnostic BMAB, and in whom the PET-CT did not show marrow signal abnormality, were excluded from the analysis. Ann Arbor stage was determined using PET-CT with and without the contribution of BMAB, and the proportion of stage IV cases by each method was measured.

RESULTS

Among 99 eligible patients, the median age was 62 years (range, 24-88 years), 62 (63%) were male, 53 (53%) had elevated serum lactate dehydrogenase, and 17 (16%) had an Eastern Community Oncology Group performance status of > 2. Thirteen (12%) patients had more than 1 extra-nodal site of lymphoma involvement. Revised International Prognostic Index score was 1 in 39 (37%) patients, 2 in 42 (40%) patients, 3 in 20 (19%) patients, and 4 in 4 (4%) patients. A total of 38 (36%) patients had BMI established by either PET-CT (n = 24; 24%), BMAB (n = 14; 14%), or by both modalities (n = 12; 12%). Twelve (50%) of the 24 patients with positive PET-CT had BMI by DLBCL, whereas only 2 (3%) of the 75 patients with negative PET-CT showed BMI. BMAB upstaged 1 (2%) of the 53 stage I/II patients to stage IV. The sensitivity and specificity of PET-CT scan to detect BMI by DLBCL was 86% (95% confidence interval, 51.9%-95.7%) and 87% (95% confidence interval, 76%-92%), respectively. Eighty-five (86%) patients had concordant results between lymphomatous BMAB and PET-CT (12 patients were positive for both; 73 patients were negative for both), and 14 (14%) patients had a discordant interpretation (2 patients were positive by BMAB and negative by PET-CT, and 12 patients were negative by BMAB and positive by PET-CT). The positive predictive value of PET-CT was only 50%, whereas the negative predictive value was 98%. The accuracy of PET-CT was 86%. Although patients with positive BMAB had inferior 5-year overall survival estimates compared with those with negative BMAB (66% vs. 85%; P = .08), no such difference was demonstrated between PET-CT-positive and PET-CT-negative patients (79% vs. 83%; P = .30).

CONCLUSIONS

In patients with newly diagnosed DLBCL, PET-CT is accurate in detecting BMI by DLBCL. Although PET-CT has a very high negative predictive value for BMI, it overestimates the number of cases with marrow involvement by DLBCL. In clinical practice, routine BMAB may no longer be necessary for all patients with DLBCL who are staged by PET-CT, unless the results would change both staging and therapy. The prognostic implication of BMI identified by PET-CT compared with BMAB remains unknown. Whether a PET-CT precludes the need for a BMAB in patients with DLBCL remains to be evaluated in a prospective study.

Implications of infiltrating immune cells within bone marrow of patients with diffuse large B-cell lymphoma

The implications of infiltrating immune cells, especially T cells and macrophages, in the bone marrow (BM) microenvironment of patients with diffuse large B-cell lymphoma (DLBCL) have rarely been studied. We aimed to investigate the significance of infiltrating immune cells in the BM microenvironment as a prognostic factor for DLBCL patients. Using the initial pretreatment BM biopsy obtained from 198 DLBCL patients, we semiquantitatively evaluated CD3+ T cells, CD8+ T cells, and CD163+ macrophages that infiltrate into the paratrabecular and interstitial areas of BM by immunohistochemistry and analyzed their clinicopathological and prognostic implications. Levels of infiltrating CD3+ T cells, CD8+ T cells, and CD163+ macrophages were significantly higher in BM with DLBCL involvement (BMI-positive group) than in that without DLBCL involvement (BMI-negative group). Infiltration of CD8+ T cells significantly increased in cases with advanced Ann Arbor stage, elevated lactate dehydrogenase level, extranodal site involvement ≥2 sites, higher Eastern Cooperative Oncology Group performance status, and higher International Prognostic Index (IPI) risk. High levels of CD3+ T cells were significantly associated with age ≤60, and high levels of CD163+ macrophages were associated with advanced Ann Arbor stage and higher IPI risk. High infiltration of CD8+ T cells was significantly related to inferior overall and recurrence-free survival rate, even in the BMI-negative group. High infiltration of CD8+ T cells within the pretreatment BM was related to poor prognosis, and might be a useful prognostic factor of DLBCL patients. Therefore, evaluation of CD8+ T cells is helpful for predicting prognosis in initial pretreatment BM biopsy of DLBCL patients.

Prognostic significance of bone marrow infiltration detected by PET-CT in newly diagnosed diffuse large B cell lymphoma

The aim of this study was to examine the prognostic value of bone marrow involvement (BMI) assessed by baseline PET-CT (PET(0)-BMI) in treatment-naïve patients with diffuse large B-cell lymphoma (DLBCL). All patients from a single centre diagnosed as DLBCL between 2005 and 2014 had data extracted from staging PET-CT (PET(0)-CT), bone marrow biopsy (BMB), and treatment records. The PET(3)-CT (PET-CT scan after cycle 3 of immunochemotherapy) was performed on all the patients with PET(0)-BMI positivity (PET(0)-BMI(+)). Of 169 patients, 20 (11.8%) had BMI on BMB, whereas 35 (20.7%) were PET(0)-BMI positive. Among PET(0)-BMI(+) patients, patients with maximum of standard uptake value (SUVmax) of bone marrow (SUVmax(BM)) more than 8.6 were significantly associated with high IPI score (3–5) (P=0.002), worse progression-free survival (PFS) and overall survival (OS) (P=0.025 and P=0.002, respectively). In the 68 stage IV cases, 3-year OS was higher in the patients with negative PET(0)-BMI (PET(0)-BMI(−)) than that with PET(0)-BMI(+) (84.2%±6.5% vs. 44.1%±8.6%; P=0.003), while 3-year PFS only shown a trend of statistic significance (P=0.077) between the two groups. Among the 69 patients of inter-risk of IPI (2–3), patients with PET(0)-BMI(+) had significantly inferior PFS and OS than that with PET(0)-BMI(−) (P=0.009 and P<0.001, respectively). The cut-off value of the decreased percentage of SUVmax(BM) between PET(0)-CT and PET(3)-CT (ΔSUVmax(BM)) was 70.0%, which can predict PFS (P=0.003) and OS (P=0.023). These data confirmed that along with the increased sensitivity and accuracy of identifying bone marrow by PET-CT, novel prognostic values of marrow involvement were found in patients with DLBCL.

High total metabolic tumor volume in PET/CT predicts worse prognosis in diffuse large B cell lymphoma patients with bone marrow involvement in rituximab era

Bone marrow involvement (BMI) in diffuse large B cell lymphoma (DLBCL) was naively regarded as an adverse clinical factor. However, it has been unknown which factor would separate clinical outcomes in DLBCL patients with BMI. Recently, metabolic tumor volume (MTV) on positron emission tomography/computed tomography (PET/CT) was suggested to predict prognosis in several lymphoma types. Therefore, we investigated whether MTV would separate the outcomes in DLBCL patients with BMI. MTV on PET/CT was defined as an initial tumor burden as target lesion ≥ standard uptake value, 2.5 in 107 patients with BMI. Intramedullary (IM) MTV was defined as extent of BMI and total MTV was as whole tumor burden. 260.5 cm(3) and 601.2 cm(3) were ideal cut-off values for dividing high and low MTV status in the IM and total lymphoma lesions in Receiver Operating Curve analysis. High risk NCCN-IPI (p<0.001, p<0.001), bulky disease (p=0.011, p=0.005), concordant subtype (p=0.025, p=0.029), high IM MTV status (p<0.001, p<0.001), high total MTV status (p<0.001, p<0.001), and ≥ 2CAs in BM (p=0.037, p=0.033) were significantly associated with progression-free survival (PFS) and overall survival (OS) than other groups. In multivariate analysis, high risk NCCN-IPI (PFS, p=0.006; OS, p=0.013), concordant subtype (PFS, p=0.005; OS, p=0.007), and high total MTV status (PFS, p<0.001; OS, p<0.001) had independent clinical impacts. MTV had prognostic significances for survivals in DLBCL with BMI.

Discordant bone marrow involvement in non-Hodgkin lymphoma

A discordant lymphoma occurs where 2 distinct histologic subtypes coexist in at least 2 separate anatomic sites. Histologic discordance is most commonly observed between the bone marrow (BM) and lymph nodes (LNs), where typically aggressive lymphoma is found in a LN biopsy with indolent lymphoma in a BM biopsy. Although the diagnosis of discordance relied heavily on histopathology alone in the past, the availability of flow cytometry and molecular studies have aided the identification of this entity. The true prevalence and clinical ramifications of discordance remain controversial as available data are principally retrospective, and there is therefore little consensus to guide optimal management strategies. In this review, we examine the available literature on discordant lymphoma and its outcome, and discuss current therapeutic approaches. Future studies in discordant lymphoma should ideally focus on a large series of patients with adequate tissue samples and incorporate molecular analyses.

Direct comparison of visual and quantitative bone marrow FDG-PET/CT findings with bone marrow biopsy results in diffuse large B-cell lymphoma: does bone marrow FDG-PET/CT live up to its promise?

BACKGROUND

Detection of bone marrow involvement using 18F-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography (FDG-PET/CT) has been proposed as a non-invasive alternative to standard blind bone marrow biopsy (BMB) of the posterior iliac crest in patients with newly diagnosed diffuse large B-cell lymphoma (DLBCL). However, studies that directly compare FDG-PET/CT results with histopathology are currently lacking.

PURPOSE

To directly compare both visual and quantitative bone marrow FDG-PET/CT to BMB at the right posterior iliac crest in patients with newly diagnosed DLBCL.

MATERIAL AND METHODS

A total of 40 patients with newly diagnosed DLBCL, who had undergone FDG-PET/CT before BMB of the right posterior iliac crest, were retrospectively included. FDG-PET/CT images were visually assessed for bone marrow involvement in the right posterior iliac crest. 3D partial volume corrected mean standardized uptake value (cSUVmean), maximum standardized uptake value (SUVmax), and peak standardized uptake value (SUVpeak) were measured in the right posterior iliac crest, using volume of interest analysis. BMB of the right posterior iliac crest was used as reference standard for bone marrow involvement.

RESULTS

Sensitivity and specificity of visual FDG-PET/CT analysis for the detection of bone marrow involvement in the right posterior iliac crest were 14.3% (95% confidence interval [CI], 0.5-53.4%) and 100% (95% CI, 87.6-100%), respectively. cSUVmean, SUVmax, and SUVpeak of BMB-negative patients (1.4 ± 0.49, 2.2 ± 0.69, and 1.7 ± 0.59, respectively) considerably overlapped with those of BMB-positive patients (1.8 ± 0.53, 2.7 ± 0.71, and 2.2 ± 0.61, respectively).

CONCLUSION

In a local, head-to-head comparison with BMB, the diagnostic value of both visual and quantitative FDG-PET/CT for the detection of bone marrow involvement is low in patients with newly diagnosed DLBCL.

Opportunities and limitations of bone marrow biopsy and bone marrow FDG-PET in lymphoma

Bone marrow involvement in lymphoma may have prognostic and therapeutic consequences. Bone marrow biopsy (BMB) is the established method for the evaluation of the bone marrow. (18)F-fluoro-2-deoxy-d-glucose positron emission tomography (FDG-PET) plays an important role in lymphoma staging, but its value in the assessment of the bone marrow and whether it can replace BMB is still a topic of debate and investigation. The purpose of this scientific communication is to provide an evidence-based overview about the opportunities and limitations of BMB and FDG-PET in the evaluation of the bone marrow in patients with lymphoma. This article first reviews the basic properties, opportunities and limitations of BMB and bone marrow FDG-PET, and then focuses on the clinical utility of BMB and bone marrow FDG-PET in three major lymphoma subtypes including Hodgkin lymphoma, diffuse large B-cell lymphoma, and follicular lymphoma.

Synchronous diffuse large B-cell lymphoma and malignant clonal plasma cells in bone marrow as primary presentation: a diagnostic and therapeutic challenge

Coexistence of Diffuse Large B-Cell Lymphoma (DLBCL) with other morphologically and phenotypically distinct lymphoid neoplasm although unusual, has been reported in literature. The most common lymphoid neoplasms associated with DLBCL are Hodgkin's lymphoma, mantle cell lymphoma and marginal zone lymphoma. However, they have been reported predominantly in the sites other than the bone marrow. Rarely, DLBCL associated with paraproteinemia of IgM type, result of monoclonal plasma cell proliferation, has also been reported in literature. There is either an associated increase in the free light chain levels or disruption in the normal kappa: lambda ratio. However, co-existence of DLBCL with malignant non secretory clonal plasma cells, diagnosed primarily in the bone marrow has not been reported in the literature.

Prognostic impact of concordant and discordant bone marrow involvement and cell-of-origin in Korean patients with diffuse large B-cell lymphoma treated with R-CHOP

AIMS

Previous studies have suggested many prognostic factors in diffuse large B-cell lymphoma (DLBCL), but the prognostic importance of cell-of-origin and discordant bone marrow involvement remains unclear. The aim of this study was to evaluate the prognostic impact of bone marrow involvement histological subtype, cell-of-origin subtype and international prognostic index (IPI) scores in patients with DLBCL.

METHODS

Patients who were newly diagnosed with DLBCL and treated with rituximab plus cyclophosphamide, doxorubicin, vincristine and prednisone (R-CHOP) were analysed. Clinical information was reviewed retrospectively. Patients were classified into negative, concordant and discordant bone marrow involvement by histological review. The cell-of-origin types were defined using immunohistochemical analysis.

RESULTS

Both concordant and discordant bone marrow involvement had a negative prognostic impact on progression-free survival, independent of the standard and National Comprehensive Cancer Network (NCCN) IPI scores and cell-of-origin. Patients with non-germinal centre B-cell type showed significantly shorter progression-free survival than those with germinal centre B-cell type. However, non-germinal centre B-cell type did not have a prognostic impact on progression-free survival or overall survival after controlling for the standard and NCCN-IPI and bone marrow involvement.

CONCLUSIONS

Both concordant and discordant bone marrow involvement had an adverse prognostic impact on progression-free survival and overall survival; this was independent of the standard and NCCN-IPI and cell-of-origin (non-germinal centre B-cell type). The NCCN-IPI had more powerful prognostic value than the standard IPI (sIPI). The non-germinal centre B-cell type lost significant prognostic impact on progression-free survival after adjustment for standard and NCCN-IPI and bone marrow involvement.

Toll-like receptor 4-induced inflammatory responses contribute to the tumor-associated macrophages formation and infiltration in patients with diffuse large B-cell lymphoma

To evaluate the expression of tumor-associated macrophages (TAMs) and Toll-like receptor 4 (TLR4) in diffuse large B-cell lymphoma (DLBCL) and their correlation with patient clinical characteristics, we detected using immunohistochemistry in 81 specimens of patients with DLBCL. The correlation between protein expression levels and clinical parameters, as well as the association between CD68 and TLR4 were analyzed. The number of CD68 TAMs was closely related to β2-microglobulin (P = .028 and P < .05), whereas there was no significant correlation between the number of CD68 TAMs and other clinical factors. Toll-like receptor 4 was related to tumor size and peripheral blood lymphocyte to monocyte ratio. The Spearman correlation coefficient indicated a significant positive correlation between CD68 TAMs and TLR4 expression (r = 0.240; P = .038, P = .05). These results, on one hand, indicated that TLR4-induced inflammatory responses may affect TAM infiltration and accumulation, and that TAMs and TLR4 may interact to play important roles in DLBCL microenvironment regulating the tumor growth, but, on the other hand demonstrated that both of TAMs and TLR4 had not only one side on DLBCL growth.