CD56 positive diffuse large B-cell lymphoma: a case report and literature review

CD56 positive B-cell lymphoma is very rare. We experienced a case of CD56 positive diffuse large B-cell lymphoma, occurred in a young child. A 5-year-old girl complained with snoring and open mouth breathing. No any abnormality in laboratory or physical examination was present, except enlarged both tonsils. Bilateral tonsillectomy was performed. Cut sections of right tonsil showed a 2 cm size, solid mass. On microscopically, large monomorphic lymphoid cells were diffusely proliferated and showed positivity for CD20 and CD56 and negative for Epstein-Barr virus (EBV) polymerase chain reaction (PCR). Monoclonality was observed on immunoglobulin heavy chain gene rearrangement. This is a unique case with incidentally found and occurred in a young child.     

Flow cytometric detection and quantification of CD56 (neural cell adhesion molecule, NCAM) expression in diffuse large B cell lymphomas and review of the literature

Stacchini A, Barreca A, Demurtas A, Aliberti S, di Celle P F & Novero D
(2012) Histopathology  60, 452–459
Flow cytometric detection and quantification of CD56 (neural cell adhesion molecule, NCAM) expression in diffuse large B cell lymphomas and review of the literature Aim: To report unusual CD56 (neural cell adhesion molecule, NCAM) expression on diffuse large B cell lymphoma (DLBCL). Methods and results: CD56 expression was first detected and quantified on tissues obtained from five cases of DLBCL by flow cytometry (FC), then confirmed by immunohistochemistry. The CD56 expression pattern was heterogeneous among the cases [the molecular equivalent of soluble fluorochrome (MESF) level ranged from 2214 to 133 466]. All were CD10 and Bcl‐6 positive, suggesting their germinal centre origin; one was also CD5 positive. An extranodal presentation occurred in three of five cases. Conclusions: CD56 expression in B cell lymphoma is a rare occurrence. FC is able to identify aberrant immunophenotypes that can be useful in the identification and monitoring of B cell lymphoma subtypes. The presence of CD56 reported by the literature on certain DLBCL with extranodal presentation might be related to mechanisms involved in growth and expansion.     

Diffuse large B-cell lymphoma with fibrillary matrix

Diffuse large B-cell lymphoma (DLBCL) with fibrillary matrix is an extremely rare variant of non-Hodgkin's lymphoma (NHL) whose pathological features are poorly known. Here, we report on our experience with such a condition arising in a 71-yr-old woman. Our findings not only demonstrate that DLBCL with fibrillary matrix actually represents a peculiar subtype of DLBCL, but they also illustrate that the cytologic and flow cytometric features in this disorder can be deceptive enough as to mislead even the most experienced cytopathologist.     

Nasopharyngeal alveolar rhabdomyosarcoma expressing CD56: a mimicker of extranodal natural killer/T-cell lymphoma

Alveolar rhabdomyosarcoma (ARMS) is remarkably rare in adults older than 45 years. Histologically, the tumor is composed of blue round cells with frequent expression of CD56 in addition to myogenic markers. Recent studies of ARMS have shown two specific recurrent translocations: PAX3-FKHR [t(2;13)(q35;q14)] or PAX7-FKHR [t(1;13)(p36;q14)]. Extranodal natural killer (NK)/T-cell lymphoma (ENKTL) occurs most frequently in the upper aerodigestive tract with a male preference in East Asia and Central and South Americas with neoplastic cells frequently expressing CD56. We report a 53-year-old Taiwanese man presenting with a nasopharyngeal mass, cervical lymphadenopathy, and multiple bone metastases. Histologically, the nasopharyngeal biopsy revealed diffuse sheets of small blue round tumor cells without obvious alveolar pattern, angioinvasion or tumor necrosis. An initial erroneous diagnosis of ENKTL was made due to CD56 expression using fresh tumor tissue with flow cytometric analysis and the patient was treated accordingly. Retrospective study showed that the tumor cells expressed CD56, desmin, and myogenin. Fluorescence in situ hybridization revealed that the tumor cells were positive for FKHR gene rearrangement, confirming the diagnosis of ARMS. Our case illustrates that a diagnosis of ENKTL based solely on CD56 expression can be misleading for a nasopharyngeal small blue round cell tumor. ARMS should be included as a differential diagnosis, and a correct diagnosis can be reached only after a high index of suspicion and a thorough histological examination with the aid of ancillary studies.     

弥漫性大B细胞淋巴瘤40例细胞病理学分析

目的 探讨细胞病理学诊断弥漫性大B细胞淋巴瘤的可行性和准确性.方法 选择40例由组织活检证实的弥漫性大B细胞淋巴瘤的细胞学病例,包括浅表淋巴结细针穿刺24例、结外包块细针穿刺6例、胸腔积液5例、腹腔积液1例、脑脊液2例、纤支镜刷片2例.对这些病例的临床特点、细胞形态和免疫细胞化学进行分析.结果 所有病例均查见较多中等偏大的淋巴样肿瘤细胞,其免疫表型为40例肿瘤细胞表达CD45(100%),39例肿瘤细胞表达CD20(97.5%),38例表达CD79α (95%),均表现为弥漫阳性,所有病例均不表达CD45RO和PCK,Ki-67增殖指数(proliferative index,PI)均值为52.1%.其中6例用细胞病理材料所作的免疫细胞化学检测中有6例表达CD45,5例表达CD20,6例表达CD79α,均不表达CD45RO和PCK,Ki-67 PI 50%～70%.40例病例中有7例(17.5%)细胞病理诊断为符合弥漫性大B细胞淋巴瘤,16例(40%)诊断为大细胞淋巴瘤,6例(15%)诊断为可疑淋巴瘤,6例(15%)误诊为低分化癌,5例(12.5%)误诊为炎性病变.结论 细胞病理虽然不是诊断弥漫性大B细胞淋巴瘤的的首选方法,但不失为一种新的尝试,仅观察细胞涂片中细胞的形态难以做出准确诊断,需要结合免疫细胞化学,流式细胞术等辅助方法来提高诊断的准确性和可靠性.     

Analysis of immunoglobulin VH genes in CD10-positive diffuse large B-cell lymphoma

CD10, a proteolytic enzyme seen in germinal center cells and in the majority of follicular lymphomas, is occasionally expressed in diffuse large B-cell lymphomas (DLBCL). To clarify the origin and cellular characteristics of CD10-positive DLBCL, we analyzed 36 de novo cases of DLBCL for somatic mutations of the immunoglobulin heavy chain variable region (VH) genes and for their immunophenotypes. Expression greater than that of grade 2 Bcl-6 was observed in 11 of the 30 CD10-negative cases (37%) and in all six CD10-positive cases (100%; P < 0.05) without expression of CD5, CD23, cyclin D1, CD30 or CD138. The average mutation frequencies of the six CD10-positive and 30 CD10-negative DLBCL were 12.9 and 9.8%, respectively. The range of SM frequencies in CD10-positive DLBCL (9.52-18.06) was distinctly narrower than that observed for CD10-negative DLBCL (0.69-26.89). These findings seem to indicate that CD10-positive DLBCL, originating from germinal center B cells, is a genetically and immunophenotypically more homogeneous group than CD10-negative DLBCL. Furthermore, three extranodal lymphomas, in five of the six CD10-positive DLBCL, showed ongoing mutation, indicating that antigen-driven, high-affinity somatic mutation may play an important role in clonal expansion in CD10-positive DLBCL. All four extranodal cases of the six CD10-positive DLBCL showed ongoing mutation and/or bcl-2/JH rearrangement. This result suggests that the cell origin of extranodal CD10-positive DLBCL may be the same as that of follicular lymphomas.     

Extranodal diffuse large B cell lymphoma of cutaneous follicle centre lymphoma type: a study of 24 patients with non-cutaneous primary limited stage extranodal diffuse large B cell lymphoma in support of a new concept

Aigner F, Korol D, Schmitt A M & Kurrer M O
(2012) Histopathology  60, 774–784 Extranodal diffuse large B cell lymphoma of cutaneous follicle centre lymphoma type: a study of 24 patients with non‐cutaneous primary limited stage extranodal diffuse large B cell lymphoma in support of a new concept Aims: Follicle centre cell lymphoma of small cell type showing either a follicular or diffuse growth pattern similar to cutaneous follicle centre lymphoma (cFCL) has been recognized in extranodal non‐cutaneous sites. Our aim was (i) to investigate whether diffuse large B cell lymphoma (DLBCL) of cFCL type could be identified in extranodal non‐cutaneous sites and (ii) whether clinical characteristics similar to primary cFCL could be recognized. Methods and results: Of 24 extranodal non‐cutaneous DLBCLs, nine (38%) had large centrocytoid morphology and 15 (62%) were either ‘centrocytoid and centroblastic’ or ‘centroblastic and immunoblastic’. Six centrocytoid cases were Irf‐4 negative, Bcl‐6 positive and at most weakly CD10‐ or Bcl‐2‐positive by immunohistochemistry, consistent with DLBCL of cFCL type. All patients with cFCL type were stage IE and were significantly younger than other patients. Recurrences occurred in two patients and were exclusively extranodal. Conclusion: Our results suggest that DLBCL of cFCL type can be identified in extranodal non‐cutaneous sites and shows clinical characteristics similar to genuine cFCL. We propose to expand the concept of cFCL to encompass large cell lymphomas in extranodal sites.     

Analysis of the immunoglobulin heavy chain gene variable region of 101 cases with peripheral B cell neoplasms and B cell chronic lymphocytic leukemia in the Japanese population

We have analyzed the immunoglobulin heavy chain (VH) gene variable regions (CDR2 and FW3) of 101 Japanese cases with peripheral B cell neoplasms. When all except one case with a deletion were graphed by frequency of replacement mutation, the 100 cases could be separated into two groups: 24 cases with zero, one and two mutations (germline or low frequency of somatic mutation); and 76 cases with three or more mutations (medium to high frequency of somatic mutation). While most mantle cell lymphoma cases (11/13) showed germline or low frequency of somatic mutation, all cases of mucosa-associated lymphoid tissue (MALT) lymphoma (11/11), follicular lymphoma (three of three cases), plasma cell myeloma (seven of seven cases) and most cases of diffuse large B cell lymphoma (DLBCL; 42/47) belonged to the latter group. These 76 cases, therefore, may be considered to show somatic hypermutation. More than half of chronic lymphocytic leukemia/small lymphocytic lymphoma cases (CLL/SLL; eight of 13) showed a hypermutated VH gene and the ratio of replacement mutation: silent mutation in CDR2 of CLL/SLL was considerably higher compared with DLBCL and MALT lymphoma, showing somatic hypermutation. When comparing VH gene type of B cell-CLL (B-CLL) among our series and those in the literature, more cases of CD5+ B-CLL in the Western literature have the VH5 and VH6 family types, while more cases in Japan are reported to have VH4 family. The occurrence of VH families in B-CLL between Japanese and Western people seems to be comparable.     

Primary intravascular large B cell lymphoma of the endometrium

Primary intravascular large B cell lymphoma (IVLBCL) of the endometrium is extremely rare. So far, only 5 cases have been reported in the English literature. We now report a new case of endometrial IVLBCL which exhibited distinct clinicopathological characteristics and meaningful laboratory tests, and also review the literature. A 66-year-old woman showed symptoms of chronic cough and choking sensation for 4 months. Following three days of vaginal bleeding she presented for examination and diagnosis. The percentage of monocytes in the blood was double that of normal levels. There was a polyp in the endometrium, which showed a number of medium–large lymphoid cells in dilated capillaries. Immunohistochemically, the lymphoid cells were immunoreactive to CD20, CD79a, Mum-1 and Foxp-1 with 85% cells immunoreactive to Ki-67. IVLBCL of the endometrium is rare and the clinical diagnosis is very difficult. Unexplained fever of old people and abnormal laboratory tests such as obvious abnormal monocyte distribution in the blood should alert the clinical doctor to the possibility of IVLBCL. A correct diagnosis mainly depends on pathological tests and immunohistochemical labeling. The prognosis of IVLBCL is poor and few patients survive longer than one year.     

Over‐expression of BACH2 is related to ongoing somatic hypermutation of the immunoglobulin heavy chain gene variable region of de novo diffuse large B‐cell lymphoma

The basic region–leucine zipper (bZip) factor BTB, CNC homology 2 (BACH2) is known to have important roles in class switch recombination and somatic hypermutation (SHM) of the immunoglobulin (Ig) gene. In this study, we investigated the relationship between the expression of BACH2 and the status of SHM of the Ig heavy chain gene variable region (IgHV) for SHM in diffuse large B‐cell lymphoma (DLBCL). We examined 20 cases of DLBCL, 13 of which were germinal center B‐cell (GCB) DLBCL and 7 were non‐GCB DLBCL. Seven cases were negative, 6 were positive (cytoplasmic expression) and 7 were strongly positive (both nuclear and cytoplasmic expression) for BACH2. Confirmed mutation (CM) was identified in 8 cases and the CM index (number of confirmed mutations per 10 subclones) was distributed from 0 to 5. A CM index of 7 strongly positive (over‐expression) cases with BACH2 were distributed from 0 to 5, and that of 7 negative and 6 positive cases were distributed from 0 to 1. Over‐expression of BACH2 was statistically related to CM index (P = 0.008). In conclusion, over‐expression of BACH2 is critical for ongoing SHM of IgHV in DLBCL, and our data suggest that BACH2 may play an essential role for SHM of the Ig gene in B‐cell lymphoma.     

The role of gender in patients with diffuse large B cell lymphoma treated with rituximab-containing regimens: a meta-analysis

Introduction

Diffuse large B cell lymphoma (DLBCL) is the most common subtype of non-Hodgkin lymphoma (NHL). Although gender has not been included in prognostic systems, male gender has been found as a bad prognostic indicator in Hodgkin lymphoma, follicular lymphoma and chronic lymphocytic leukemia. The relationship between gender and prognosis is not clear in patients with DLBCL treated with rituximab-containing regimens. The aim of this meta-analysis is to determine the prognostic/predictive role of gender in patients with DLBCL treated with rituximab-containing regimens.

Material and methods

We systematically searched for studies investigating the relationships between gender and prognosis in DLBCL treated with rituximab-containing regimens. After careful review, survival data were extracted from eligible studies. A meta-analysis was performed to generate combined hazard ratios for overall survival, disease-free survival (DFS) and event-free survival (EFS).

Results

A total of 5635 patients from 20 studies were included in the analysis. Our results showed that male gender was associated with poor prognosis in terms of overall survival (OS) (hazard ratio (HR) = 1.155; 95% confidence interval (CI): 1.037–1.286; p < 0.009). The pooled hazard ratio for DFS and EFS showed that male gender was not statistically significant (HR = 1.219; 95% CI: 0.782–1.899; p = 0.382, HR = 0.809; 95% CI: 0.577–1.133; p = 0.217).

Conclusions

The present meta-analysis indicated male gender to be associated with a poor prognosis in patients with DLBCL treated with rituximab-containing regimens.     

B cell lymphoma,unclassifiable, with features intermediate between diffuse large B cell lymphoma and classical hodgkin lymphoma: Diagnosis by fine‐needle aspiration cytology

A 58‐year‐old lady presented with mediastinal lymphadenopathy. A thoracoscopic ultrasound‐guided fine‐needle aspiration showed large atypical epithelioid cells arranged in cohesive sheets and dispersed as single cells with intact cytoplasm amid a background of lymphocytes and histiocytes. A cytological diagnosis of “a malignant neoplasm” was made, raising a broad list of differential diagnoses. A broad panel of immunocytochemical stains performed on the cell block was indicative of a lymphoproliferative disorder, but the immunophenotype was intermediate between diffuse large B cell lymphoma (DLBCL) and classical Hodgkin lymphoma (cHL). Diffuse and strong reactivity to CD20, CD79a, and PAX‐5, and weak reactivity to CD30, was in favor of a DLBCL, or more precisely mediastinal (thymic) large B cell lymphoma (MLBL). However, there were negative staining for LCA, OCT‐2, and BOB‐1 as well as positive staining for EBV‐encoded RNA, which were against a diagnosis of MLBL and raised the possibility of cHL. The absence of RS cells and the typical mileu, the negativity for CD15 and the strong positivity of CD20 and PAX‐5 were against a diagnosis of cHL. On this basis, the diagnosis of “B‐cell lymphoproliferative disorder with features intermediate between DLBCL and cHL” was rendered. The diagnosis was subsequently confirmed on excisional biopsy. This case report demonstrates broad differential diagnoses raised by this diagnostic entity and the importance of an adequate cell block for accurate designation. Diagn. Cytopathol. 2014;42:690–693. © 2013 Wiley Periodicals, Inc.     

Expression of CD56 antigen in Langerhans cell histiocytosis associated with T-lymphoblastic lymphoma in a same lymph node

Association of T-lymphoblastic lymphoma (LBL) and Langerhans cell histiocytosis (LCH) in the same lymph node is very rare. Herein, we report such two cases with expression of CD56 in Langerhans cells. Immunohistochemically, lymphoblasts were positive for anti-polyclonal CD3 antibody, CD34, CD7, CD99, and terminal deoxynucleotidyl transferase. LCH cells were positive for anti-S100 protein, CD1a, CD4, CD56, and CD68. Although those two populations were separated topographically, many histiocytes intermingled with lymphoblasts in the paracortex and a few lymphoblasts were scattered within the intrasinusoidal sheets of histiocytes. Neither admixed eosinophils nor multinucleated giant cells were observed. The pathogenetic mechanism of CD56 expression in LCH associated with LBL is discussed.     

A case of natural killer/T cell lymphoma of the subcutis resembling subcutaneous panniculitis-like T cell lymphoma

A case of nasal type natural killer (NK)/T cell lymphoma of the subcutis showing clinical and morphological features that resemble subcutaneous panniculitis-like T cell lymphoma (SPTCL) is presented. A 73-year-old man presented with swelling of the left arm and was diagnosed with panniculitis by a dermatologist. It was concluded from a skin biopsy specimen that the patient had non-Hodgkin's lymphoma of the large cell, NK/T cell type because the neoplastic cells showed polyclonal CD3 immunoreactivity. Treatment with interferon-gamma was initiated, but the patient died of disseminated intravascular coagulation and multiple organ failure 2 months after the initial symptoms appeared. However, involvement of additional organs by the lymphoma was not apparent clinically. An autopsy was not performed. A routinely stained section of the biopsy skin specimen revealed massive necrosis of the subcutaneous fat, karyorrhexis admixed with reactive histiocytes, and large atypical lymphoid cells. Immunoreactivity for polyclonal CD3 was present in the perinuclear region, but absent in the neoplastic cell membranes. CD56, CD45RO (UCHL-1), CD43 (MT1), CD45 (leukocyte common antigen), and the cytotoxic molecules perforin, granzyme B and TIA-1 were positive, but CD20 (L26), CD4, CD8, and betaF1 were negative. Epstein-Barr virus (EBV) mRNA was detected in the nuclei of neoplastic cells by in situ hybridization. Subcutaneous panniculitis-like T cell lymphoma is reported to be an EBV-negative, clonal T cell neoplasm. Although this case showed clinical and morphological features that resembled SPTCL, perinuclear polyclonal CD3 staining and membranous CD56 reactivity seen in neoplastic cells were suggestive of NK cells. Furthermore, the neoplastic cells were positive for EBV. This case is considered to be a NK/T cell lymphoma of the subcutis resembling SPTCL. It is believed that it is important to recognize such a tumor because patients may undergo a fulminant clinical course, despite the tumor being localized in the subcutaneous adipose tissue.     

Sequential development of diffuse large B-cell lymphoma in a patient with angioimmunoblastic T-cell lymphoma

Lymphoma of different histologic type can occur in the same patient. Here, we describe a 64-year-old male patient with angioimmunoblastic T-cell lymphoma (AITL) who subsequently developed diffuse large B-cell lymphoma (DLBCL). At the time of initial diagnosis, histologic examination of a left inguinal lymph node of the patient and a monoclonal pattern of TCRβ gene rearrangement showed typical features of AITL, and there was no evidence of a monoclonal B-cell population. Twenty-six months later, he had generalized lymphadenopathy and organs involvement by DLBCL. A monoclonal IgH gene rearrangement proved de novo development of secondary B-cell lymphoma and excluded relapse of a primary composite lymphoma. The in situ hybridization analysis showed Epstein-Barr-encoded RNA (EBER) sporadic positivity in sample collected from AITL but extensive positivity in the immunoblasts collected from DLBCL. Our observation supports the hypothesis that Epstein-Barr virus (EBV) is etiologically related to AITL in this case. Clonal expansion of EBV-associated DLBCL is a secondary event in AITL via EBV infection or reactivation.     

Clinicopathologic differences between 22 cases of CD56-negative and CD56-positive subcutaneous panniculitis-like lymphoma in Japan

CD56 is an important marker for prospecting clinicopathologic features of cytotoxic T-cell and natural killer (NK)/T-cell lymphomas. We examined 22 cases of subcutaneous panniculitis-like lymphoma and classified these into CD56-positive and CD56-negative groups. The 11 CD56-negative cases were mainly in the younger age group and had systemic subcutaneous nodules without ulceration. They exhibited subcutaneous invasion by medium-sized lymphoma cells, scattered erythrophagocytosis, patchy necrosis, and little tumor invasion in the superficial dermis. Their lymphoma cells had characteristics of CD3 epsilon-, CD8-, TcR beta F1-, T-cell intracellular antigen (TIA)1-, and granenzyme B-positive cytotoxic T cells and were negative for apoptosis-promoting proteins CD95 (Fas), Bax, CPP32 (caspase 3), and p53 (DO7). Ten patients were alive despite clinical signs of hemophagocytic syndrome and relapses in 7 cases. The 11 CD56-positive cases had systemic ulcerative skin tumors composed of pleomorphic lymphoma cells with massive necrosis and little erythrophagocytosis involving the subcutis and also often the whole dermis. Their tumor cells were positive for CD3 epsilon, TIA1, granenzyme B, CD95, CD95L (Fas ligand), Bax, and CPP32. Three cases were of the TcR beta F1-positive phenotype, 1 was of the TcR gamma/delta-positive T-cell phenotype, and 6 were of the TcR beta F1- and TcR gamma/delta-negative NK/T-cell phenotype. Six cases were p53 (DO7) positive. Seven cases had complications of liver dysfunction and cytopenia, and 8 died of disease. One CD56-negative case and 3 CD56-positive cases had nuclear signals of Epstein-Barr virus-encoded RNA in their lymphoma cells. The 2 groups had significantly (P <0.01) different prognoses by Kaplan-Meier and log-rank methods. Patients with CD56-negative and CD56-positive groups had statistically different clinicopathologic, immunohistologic, and functional findings and prognoses.     

CXCR4 expression enhances diffuse large B cell lymphoma dissemination and decreases patient survival

The chemokine receptor CXCR4 has been implicated in the migration and trafficking of malignant B cells in several haematological malignancies. Over‐expression of CXCR4 has been identified in haematological tumours, but data concerning the role of this receptor in diffuse large B cell lymphoma (DLBCL) are lacking. CXCR4 is a marker of poor prognosis in various neoplasms, correlating with metastatic disease and decreased survival of patients. We studied CXCR4 involvement in cell migration in vitro and dissemination in vivo. We also evaluated the prognostic significance of CXCR4 in 94 biopsies of DLBCL patients. We observed that the level of expression of CXCR4 in DLBCL cell lines correlated positively with in vitro migration. Expression of the receptor was also associated with increased engraftment and dissemination, and decreased survival time in NOD/SCID mice. Furthermore, administration of a specific CXCR4 antagonist, AMD3100, decreased dissemination of DLBCL cells in a xenograft mouse model. In addition, we found that CXCR4 expression is an independent prognostic factor for shorter overall survival and progression‐free survival in DLBCL patients. These results show that CXCR4 mediates dissemination of DLBCL cells and define for the first time its value as an independent prognostic marker in DLBCL patients. Copyright © 2014 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd