Genotypic and phenotypic differences between nodal and extranodal diffuse large B-Cell lymphomas

Diffuse Large B-Cell Lymphoma Germinal Center B-Cell Subtype of the Thyroid

Non-Hodgkin lymphoma is one of the most common hematological malignancies having both nodal and extranodal sites of involvement. The thyroid gland is one of the rarest primary sites. Most cases of primary thyroid lymphoma are diffuse large B-cell in nature; thus, aggressive and in extreme cases can rapidly lead to airway compromise, especially in patients who have been living with goiter for years. We present one such case of a 64-year-old female who presented with signs of airway compromise, requiring emergent airway intubation and surgical debulking. She was treated with emergent chemotherapy (DA-EPOCH-R regimen), without radiotherapy and this resulted in complete remission.

Cutaneous involvement in diffuse large B cell lymphoma at presentation: report of two rare cases and literature review

BACKGROUND

Diffuse large B cell lymphoma (DLBCL) can occur at nodal and/or extra-nodal sites. After the gastrointestinal tract, cutaneous involvement predominates in extra-nodal DLBCL. Skin involvement at presentation can be in the form of plaques, papules, nodules or ulcers. Differentiating primary cutaneous DLBCL from systemic DLBCL with cutaneous involvement is important for appropriate patient management.

CASE PRESENTATION

We describe here, two interesting cases of skin involvement in DLBCL- one primary cutaneous DLBCL and the other, cutaneous involvement in systemic DLBCL with different clinico-pathological profiles. Though both cases had almost similar morphology of the skin lesions (ulcero-proliferative) at presentation, the disease was confined to the skin in the former, while the latter had involvement of lymph nodes and bone marrow.

CONCLUSIONS

Meticulous clinical evaluation, appropriate histopathological and immunohistochemical workup helped in their diagnosis and correct classification of the disease status, guiding the further treatment decisions.

Value of 18F-FDG PET/CT for prognostic stratification in patients with primary intestinal diffuse large B cell lymphoma treated with an R-CHOP-like regimen

PURPOSE

The prognostic value of ¹⁸F-FDG PET/CT for primary intestinal diffuse large B-cell lymphoma (PI-DLBCL) patients has not been determined. This prompted us to explore the value of ¹⁸F-FDG PET/CT for prognostic stratification in patients with PI-DLBCL treated with an R-CHOP-like regimen.

MATERIALS AND METHODS

Seventy-three PI-DLBCL patients who underwent baseline PET/CT between January 2010 and May 2019 were included in this retrospective study. Total metabolic tumor volume (TMTV) and total lesion glycolysis (TLG) were computed using the 41% SUV_max thresholding method. Progression-free survival (PFS) and overall survival (OS) were used as endpoints to evaluate prognosis.

RESULTS

During the follow-up period of 3-117 months (29.0 ± 25.5 months), high TLG, non-germinal center B-cell-like (non-GCB) and high National Comprehensive Cancer Network International Prognostic Index (NCCN-IPI) were significantly associated with inferior PFS and OS. TLG, cell-of-origin and NCCN-IPI were independent predictors of PFS, and both TLG and NCCN-IPI were independent predictors of OS. The grading system was based on the number of risk factors (high TLG, non-GCB, high NCCN-IPI) and patients were divided into 4 risk groups (PFS: χ² = 33.858, P < 0.001; OS: χ² = 29.435, P < 0.001): low-risk group (none of the 3 risk factors, 18 patients); low-intermediate risk group (1 risk factor, 24 patients); high-intermediate risk group (2 risk factors, 16 patients); and high-risk group (all 3 risk factors, 15 patients).

CONCLUSIONS

High TLG, non-GCB and high NCCN-IPI can identify a subset of PI-DLBCL patients with inferior survival outcomes. Furthermore, the grading system can identify PI-DLBCL patient groups with markedly different prognoses, which might contribute to the adjustment of the therapeutic regime.

C-MYC, BCL2 and BCL6 Translocation in B-cell Non-Hodgkin Lymphoma Cases

C-MYC, BCL2 and BCL6 genes are the most commonly oncogenes involved in B-Cell lymphomas. Translocations of these oncogenes are associated with an aggressive clinical course. This study aims to elucidate the patterns of BCL6, BCL2 and C-MYC gene aberrations among Malaysian B-cell Non-Hodgkin Lymphoma (NHL) using fluorescence in situ hybridization (FISH). Eighty-one B-cell NHL tissue blocks were retrieved between the year 2011 to 2015 and investigated using immunohistochemistry and interphase FISH dual colour break-apart probes of BCL2, BCL6, C-MYC and IgH. A significant difference was detected between the nodal and extranodal sites in all the BCL2 (p=0.01), C-MYC (p=0.03) and IgH (p=0.006) cases except for BCL6 (p=0.2). Our study showed that BCL6 had the highest gene translocation while BCL2/BCL6 had the most mixed aberrations of gain copies and translocation, however no mixed aberrations of gain copies and translocation was found in C-MYC. None of the mixed gain copies and translocation was found in any of the germinal centre B-cell (GCB) subtype of Diffuse Large B-cell Lymphoma, however, five were found in BCL6 and IgH gene in the non-GCB subtype; while mixed gain copies and translocation cases of BCL2 gene was found in the Follicular Lymphoma cases only. The study found interesting findings of BCL2, C-MYC and IgH gene aberrations between nodal and extranodal sites. This information might benefit future study in predicting prognosis and determine effective therapeutic strategies in the multi-ethnic populations of Malaysia as well as the Asian population.

Primary extranodal diffuse large B-cell lymphomas: Many sites, many entities? Clinico-pathological, immunohistochemical and cytogenetic study of 106 cases

We analyzed the clinicopathological, immunohistochemical and cytogenetic features of 106 extranodal (EN) diffuse large B-cell lymphomas (DLBCLs) from stomach (34 cases), intestine (10), cervico-cephalic region (11), central nervous system (13), testes (21), skin (8), and miscellaneous sites (9). Hans' algorithm and the immunohistochemical double expressor score (DES) for MYC and BCL2 were applied to all cases. A subset of fifty-eight cases were analyzed with fluorescent in situ hybridization (FISH) with specific break apart probes for BCL6, MYC, BCL2, CCND1, BCL10 and MALT1 genes. Clinical records were available for all patients. The immunohistochemical study showed that, in our series of EN-DLBCLs, the Hans' subgroup and the DES differed significantly according to the site of origin. At FISH analysis, BCL6 and BCL2 were the most commonly rearranged genes in non-GC and in GC cases, respectively. Gastrointestinal lymphomas displayed the highest rate of gene rearrangements, often with MYC involvement. One testicular DLBCL showed BCL2/MYC double hit. At survival analysis, cerebral and testicular origin was associated with poor prognosis. In addition, Hans' subgroup and other immunohistochemical markers influenced patients' outcome. In conclusion, our data suggest that immunophenotypic, genetic and survival characteristics of EN-DLBCL are related to the specific primary site of the disease.

Molecular Subtypes, Apoptosis and Proliferation Status in Indonesian Diffuse Large B-Cell Lymphoma Cases

Objective:

The diffuse large B-cell lymphoma (DLBCL) has two major molecular subtypes, germinal center B-cell-like (GCB) and non-GCB. These have differing behavior which affects overall patient survival. However, immunohistochemistry based molecular subtyping of Indonesian DLBCLs has been limited. This was the focus of the present study, with a focus of attention on the apoptotic index (AI) and the proliferation index (PI) of the two molecular subtypes.

Materials and Methods:

During the study period of 3.5 years, a total of 98 cases of DLBCL were identified. Molecular subtypes and PI were determined by immunohistochemistry and TUNEL method was used to determine the AI.

Result:

GCB accounted for 31 cases (31.6%) and non-GCB the remainder (68.4%). Gender showed a slight male predominance (54 cases, 55.1%), with a higher incidence in the extra-nodal region (57 cases, 58.2%). The AI and PI were significantly higher in GCB (p<0.001 in the Mann-Whitney test) and a Spearman correlation coefficient test showed that PI was positively correlated with AI (r=0.673, p<0.001).

Conclusion:

The findings indicate that the non-GCB subtype is more common than GCB in Indonesian DLBCL. GCB features significantly higher PI and AI, which themselves appear linked.

Estrogen receptor beta expression and prognosis of diffuse large B cell lymphoma

OBJECTIVES

Estrogen receptor beta (ERβ)-selective agonists inhibited B cell lymphoma growth in animal models. However, a recent study found that higher ERβ expression in tissue from diffuse large B cell lymphoma (DLBCL) patients indicated a poorer survival. This study aimed to determine the ERβ expression in DLBCL tissue using immunohistochemistry and correlate with clinical outcomes.

METHODS

Diagnostic tissues from newly diagnosed adult DLBCL patients treated with Rituximab-Cyclophosphamide/Doxorubicin/Vincristine/Prednisolone were counted for ERβ1-expressing cells. Nodal lymphoma (N = 41) was analyzed separately from extra-nodal DLBCL (N = 31).

RESULTS

On immunohistochemistry, ERβ1 was expressed in 73.6% of cases with the median expressing cells of 20%. For nodal lymphoma, high ERβ expression (≥25%) was associated with poorer event free survival (EFS) independent of the international prognostic index with the adjusted hazard ratio (HR) of 2.49 (95% Confidence interval (CI) 1.03-6.00, P = 0.042). On the contrary, high ERβ expression (≥25%) was associated with superior outcomes in extra-nodal DLBCL with the adjusted HR of 0.25 (95% CI 0.09-0.75, P = 0.013) for EFS and adjusted HR of 0.29 (95% CI 0.10-0.85, P = 0.024) for overall survival in multivariate analyses.

CONCLUSION

ERβ1 protein expression represented opposite prognostic factors in nodal vs. extra-nodal DLBCL.

Rare case of primary pleural lymphoma presenting with pleural effusion

Primary pleural lymphoma is rare and has been described in association with human immunodeficiency virus (HIV) infection or pyothorax. We report a rare case of primary pleural lymphoma in a 73-year-old man who presented with chest pain and no history of HIV infection or pyothorax. Chest imaging showed pleural thickening and pleural effusion. Thoracoscopic pleural biopsy was performed. Histopathological and immunohistochemical examinations conformed to that of a diffuse large B-cell lymphoma. Physicians should be aware of this rare location of primary lymphoma and implement thoracoscopy as soon as possible.

Genetic and immunohistochemical characterization of Epstein-Barr virus-associated diffuse large B-cell lymphoma

Epstein-Barr virus (EBV) has a pathogenic role in several lymphomas, including diffuse large B-cell lymphoma (DLBCL). EBV-associated genetic aberrations in DLBCL have not been fully characterized. The aim of this study was to investigate the prevalence of EBV infection in sporadic DLBCL cases in Kuwait and to evaluate their EBV status in relation to demographic data, the anatomical disease site, immunophenotypic features, particularly pertaining to the Choi's DLBCL prognostic classification, and chromosomal aberrations. Using immunohistochemistry (IHC), in situ hybridization (ISH), nested polymerase chain reaction (nPCR) and comparative genomic hybridization techniques, formalin-fixed paraffin-embedded blocks of archived DLBCL cases were included and evaluated in the study. EBV was detected in 6.9, 18.2 and 25% of the studied cases using IHC, ISH and nPCR, respectively, indicating that nPCR is more sensitive in detecting EBV than IHC and ISH. EBV- DLBCL cases showed BCL6 protein expression more frequently than EBV+ DLBCL cases. The reported prevalence of EBV+ DLBCL cases in this study is similar to that reported in the literature using ISH results and higher using nPCR results. There was a significant inverse correlation between BCL6 protein expression and the presence of EBV (p = 0.01).