[Follicular dendritic cell sarcoma: a clinicopathologic analysis of ten cases].

OBJECTIVE: To study the clinicopathologic features of follicular dendritic cell sarcoma (FDCS) and its differential diagnosis. METHODS: Ten cases of FDCS were studied by light microscopy, immunohistochemistry and in-situ hybridization. The clinical features and follow-up information were analyzed. RESULTS: Amongst the 10 cases of FDCS studied, the male-to-female ratio was 1:1. The mean age of the patients was 42 years. Six of them were located in cervical and peritoneal lymph nodes and four in extranodal sites (including tonsil, pelvic cavity, tail of pancreas and spleen). Histologically, the tumor cells had whorled, storiform or diffuse growth patterns. They were spindle in shape and contained syncytial eosinophilic cytoplasm, with round or oval nuclei, vesicular chromatin, distinct nucleoli and a variable number of mitotic figures. Multinucleated tumor giant cells and intranuclear pseudoinclusions were occasionally seen. There was a sprinkling of small lymphocytes and neutrophils within the tumor as well as in the perivascular region. Immunohistochemical study showed that the tumor cells were diffusely or focally positive for CD21, CD23, CD35 and D2-40, but negative for LCA, CD20, CD3, CD1a, HMB45 and CK. Some of them showed EMA, CD68 and S-100 reactivity. In-situ hybridization for Epstein-Barr virus-encoded RNA (EBER) showed positive signals in only one case (which was diagnosed as inflammatory pseudotumor-like FDCS). Of the 7 patients with follow-up information available (duration: 2 months to 39 months; mean: 14 months), 2 cases with paraneoplastic pemphigus died of pulmonary infection at 5 and 7 months respectively. The remaining 5 patients were alive and disease-free after surgical excision (+/- chemotherapy and radiotherapy). CONCLUSIONS: FDCS is a rare low to intermediate-grade malignant tumor. Appropriate application of FDC markers, such as CD21, CD35 and D2-40, would be helpful for arriving at a correct diagnosis. Most cases are associated with good prognosis after surgical treatment, with or without chemotherapy and radiotherapy. Patients with paraneoplastic pemphigus carry a less favorable prognosis.

[Clinicopathologic study of 963 cases of mature T-cell and natural killer/T-cell lymphoma with respect to 2008 WHO classification of lymphoid neoplasms].

OBJECTIVE: To study the clinicopathologic features of various types of mature T-cell and natural killer (NK)/T-cell lymphoma in Guangdong, China, with respect to the 2008 WHO classification of lymphoid neoplasms. METHODS: Eleven hundred and thirty-seven (1137) cases of mature T-cell or NK/T-cell lymphoma diagnosed during the period from 2002 to 2006 in Guangzhou area were retrieved. The clinical data, histologic features and immunohistochemical findings were reviewed by a panel of experienced hematopathologists. Additional immunostaining was performed if indicated. The cases were re-classified according to the 2008 WHO classification of lymphoid neoplasms. RESULTS: Nine hundred and sixty-three (963) cases fulfilled the diagnostic criteria of mature T-cell or NK/T-cell lymphoma and accounted for 20.1% of all cases of lymphoma encountered during the same period (963/4801). A predominance of extranodal involvement was noted in 644 cases (66.9%), while 319 cases (33.1%) showed mainly nodal disease. The prevalence of various lymphoma subtypes was as follows: peripheral T-cell lymphoma, unspecified (PTCL, NOS) 293 cases (30.4%), extranodal NK/T-cell lymphoma, nasal type 281 cases (29.2%), anaplastic large cell lymphoma (ALCL) 198 cases (20.6%), and angioimmunoblastic T-cell lymphoma (AILT) 46 cases (4.8%). The male-to-female ratio was 1.99. The median age of the patients was 44 years, with the peak age of PTCL, NOS, extranodal NK/T-cell lymphoma, nasal type and AILT being 55 to 64 years, 25 to 54 years and 65 to 74 years, respectively. ALK-positive ALCL occurred more frequently in young age, while the ALK-negative ALCL cases occurred mainly in the elderly. CONCLUSIONS: Extranodal lesions predominate in mature T-cell and NK/T-cell lymphomas occurring in Guangzhou area. There is a male predominance and the overall incidence shows no increasing trend with age of the patient. The peak age of various subtypes however varies. The most common subtype was PTCL, NOS, followed by extranodal NK/T-cell lymphoma, nasal type, ALCL and AILT. The relatively frequent occurrence of extranodal NK/T-cell lymphoma, nasal type in Guangdong area is likely associated with the high incidence of Epstein-Barr virus infection there.

Investigation of T-cell receptor-gamma gene rearrangement in gastrointestinal lymphomas by PCR-SSCP analysis.

AIM: To analyze the characterization of T-cell receptor-gamma (TCR-gamma) gene rearrangement in the gastrointestinal lymphomas and evaluate the value of PCR-SSCP analysis in gastrointestinal lymphomas investigation. METHODS: TCR-gamma gene rearrangement segments of gastrointestinal lymphomas were cloned and sequenced. Single clone plasmid and mixed clone plasmids were subsequently submitted to PCR-SSCP analysis to investigate the relationship between the number of amplified clones and band patterns of the amplified products. The PCR products of TCR-gamma gene rearrangement of 40 gastrointestinal lymphomas were electrophoresed on agarose gels and the positive cases on agarose gels were studied by SSCP analysis. RESULTS: The sequencing showed that TCR-gamma gene rearrangement of the gastrointestinal lymphomas included functional gene and pseudogene with extensive variety in the junctional regions. In SSCP analysis, the number of the single-stranded bands was about two times of the number of amplified clones, and double-stranded band became broad with the increased number of the amplified clones. Thirteen of the 25 B-cell gastrointestinal lymphomas and 14 of the 15 gastrointestinal T-cell lymphomas were positive detected on agarose gel electrophoresis. Of the positive cases detected by SSCP analysis, 3 B-cell lymphomas and 13 T-cell lymphomas showed positive bands. The other cases showed only smears. The rearranged pattern included 13 monoallelic gene rearrangements and 3 biallelic or oligoclonal gene rearrangements. CONCLUSION: The pattern of TCR-gamma gene rearrangement in gastrointestinal lymphomas are similar to that of the nodular lymphomas. PCR-SSCP analysis for TCR-gamma gene rearrangement can be applied both for adjuvant diagnosis of gastrointestinal lymphomas and analysis of the gene rearrangement pattern. The ratio of TCR-gamma gene rearrangements occurred in T-cell gastrointestinal lymphomas is significantly higher than that in B-cell gastrointestinal lymphomas. The gene rearrangement pattern involves monoallelic and biallelic (or oligoclonal) gene rearrangement.

Immunohistochemical detection of Kikuchi's lymphadenitis.

OBJECTIVE: To evaluate significance of immunohistochemistry in Kikuchi's lymphadenitis (KFD). METHODS: Biopsy specimens were obtained from 42 KFD cases for microscopic examination after the sections were stained with haematoxylin and eosin, and the immunohistochemical features were analyzed by monoclonal antibodies (CD20, CD8, CD45RO, CD57, CD68) and polyclonal antibody (myeloperoxidase, MPO). RESULTS: Morphologically, the lymph node lesions comprised various histiocytes, plasmacytoid monocytes, immunoblasts, small lymphocytes and nuclear fragments. In all the cases, the histiocytes were invariably observed and most of them were positive for CD68 and MPO. Immunoblasts and plasmacytoid monocytes were easily observed in proliferative stage. Immunohistochemical examination revealed strong focal T-cell positivity for the antibodies but with scarce B cell (CD20) and NK cell (CD57) positivity in the lesion area, where few or virtually no neutrophils were seen. CONCLUSION: Immunohistochemical analysis can be crucial for the differential diagnosis of KFD.

[Hepatosplenic gammadeltaT-cell lymphoma: a clinicopathological study].

OBJECTIVE: To explore the clinicopathologic features and immunophenotype of hepatosplenic gammadeltaT-cell lymphoma. METHODS: A case of hepatosplenic gammadeltaT-cell lymphoma was studied with conventional histopathological and immunohistochemical staining in combination of literature review. RESULTS: Diffuse hepatic and splenic enlargement was found in this case. Microscopically, the liver and spleen showed marked sinusoidal infiltration. The cells of hepatosplenic T-cell lymphoma were homogeneous, medium in size with pale cytoplasm, and the nuclear chromatin was loosely condensed with small inconspicuous nucleoli. The neoplastic cells were positive for CD45RO, CD3 and TIA-1, but negative for CD57, CD20 and CD79a. CONCLUSION: Hepatosplenic gammadeltaT-cell lymphoma is a rare form of peripheral T-cell lymphoma and has usually poor prognosis, which should be differentiated from other lymphomas or leukemia.

[Detection of IgH gene rearrangement in Reed-Sternberg cells microdissected from classical Hodgkin's lymphoma].

OBJECTIVE: To study the origins and clonality of Hodgkin and Reed-Sternberg (H/RS) cells and their relations with the background lymphocytes in classical Hodgkin's lymphoma. METHOD: IgH gene rearrangement was detected in paffin-embedded tissues from 33 patients with Hodgkin's lymphoma and a further analysis of the gene rearrangement was conducted in 6 of the positive cases identified after immunostaining of the sections with B-cell-specific activator protein (BSAP) followed by microdissection of the positivity labeled H/RS cells and background lymphocytes. RESULTS: IgH gene rearrangement was identified in 16 of the 33 cases. Microdissection of the lymphoma tissues was successfully performed in the 6 positive cases, and of the 19 tubes of H/RS cells obtained, 14 presented clonal bands of the rearrangement, and difference in cell numbers did not significantly influence the positive rate (P=0.290); in the 12 tubes of microdissected background lymphocytes obtained, 2 were positive for the rearrangement, and the positive rates for the rearrangement significantly differed between H/RS cells and the background lymphocytes (P=0.002). CONCLUSION: The results appear to support the hypothesis that H/RS cells originates from B cells, and a part of the background lymphocytes may possess neoplastic proliferation potentials to function as the precursors of H/RS cells.

Expression of cyclin D1 in small cell lymphoma and its clinical implications.

OBJECTIVE: To observe the expression of cyclin D1 and explore its clinical significance in small cell lymphoma. METHODS: Immunohistochemical method was used to detect the expression of CD20, CD45RO and cyclin D1 in 31 formalin- fixed and paraffin-embedded tissue samples of human small cell lymphomas. RESULTS: Twenty-eight cases were categorized into B cell lymphoma and 3 into T cell lymphoma. Only 5 cases of B cell lymphoma had cyclin D1 expression (17.86%) that did not significantly differ between nodal and extranodal lymphomas (P>0.05), indicating the presence of mantle cell lymphoma. CONCLUSION: The overexpression of cyclin D1 is a highly characteristic and specific indicator that discriminates mantle cell lymphoma from other small cell lymphomas, and this protein may offer critial guidance for therapeutic protocol and prognostic estimation.

Expressions of latent membrane protein 1, p53 and bcl-2 proteins and their significance in Hodgkin's lymphoma.

OBJECTIVE: To study the expressions of latent membrane protein 1 (LMP1), p53 and bcl-2 proteins and investigate their significance in the pathogenesis of Hodgkin's lymphoma. METHODS: Immunohistochemical staining was used to examine the expressions of LMP1, bcl-2, and p53 proteins in 31 paraffin-embedded tissue samples from Hodgkin's lymphoma. RESULT: The positivity rates of LMP1, p53 and bcl-2 proteins were 58.1% (18/31), 61.3% (19/31) and 35.5% (11/31), respectively, showing a statistically significant difference between the expressions of the former 2 proteins. CONCLUSION: p53 may be involved as an important agent in the pathogenesis of Hodgkin's lymphoma induced by LMP1, whereas bcl-2 appears unrelated to the development of this disease.

[Expression of miR-9 in B lymphocytes and B cell lymphomas cell lines and its significance].

OBJECTIVE: To investigate the expression of miR-9 in B lymphocytes, B cell lymphoma and classical Hodgkin's lymphoma (cHL) cell lines and its significance. METHODS: CD19(+) B lymphocytes were sorted from normal lymph node by magnetic beads. Total cellular micro-RNA was extracted from cHL cell line L428, B cell lymphoma cell lines Ly1 and Ly10 (diffuse large B cell lymphoma), Raji cells (Burkitt's lymphoma) and CD19(+) B lymphocytes, respectively. These micro-RNAs were separately transformed into cDNA by reverse transcription. The expression levels of miR-9 were measured by fluorescence quantitative PCR. In situ hybridization was used to detect the expression of miR-9 in cell lines. RESULTS: The expression of miR-9 was high in L428 cells (104.44 ± 1.61), and low in cell lines of B cell lymphoma (Ly1: 2.17 ± 0.38; Ly10: 1 ± 0.015; Raji: 2.65 ± 0.89), and extremely low in CD19(+) B lymphocytes (0.0026 ± 0.00040). Compared with that in the other cell lines, the expression of miR-9 in L428 cells was statistically significant (P < 0.05). miR-9 localized in the cytoplasm diffusely and strongly in L428, but scattered and slightly with some prominent distribution around the nuclear membranes in Ly1 and Ly10, and only weakly in Raji. CONCLUSIONS: miR-9 highly expressed in cHL cell line and might be a molecular marker for diagnosis and treatment of cHL.

[Primers for detecting gene rearrangement in different regions of immunoglobulin heavy chain genes and their application in diagnosis of paraffin-embedded lymphoma tissues].

OBJECTIVE: To analyze and optimize the gene rearrangement primers of different frame regions (FR) of immunoglobulin heavy chain (IgH) genes by bioinformatic methods and explore the application of these primers in the detection of paraffin-embedded lymphoma tissues. METHODS: Three pairs of primers from IgH FR1, FR2 and FR3 regions (P1c, P2A and P31, respectively) were selected as the B cell gene rearrangement primers after comparison of the gene fragments in 44 IgH variable and 6 joining regions. Using one pair of T cell receptor (TCR) gamma primer as the T cell gene rearrangement primer, 101 histopathologically confirmed lymphoproliferative samples including 80 B cell lymphomas, 14 T cell lymphomas, and 7 reactive proliferative lymph nodes were examined by PCR for gene arrangement. The DNAs from DG75 and Jurkat cell lines were used as the positive controls for B and T cell lymphoma, respectively, with those from reactive proliferative lymph nodes as the negative control. RESULTS: The positivity rates of IgH primers (P1c, P2A and P31) in the 80 B cell lymphomas were 37.5% (30/80), 52.5% (42/80) and 70.0% (56/80), respectively, and only one of the 14 T cell lymphoma cases was positive for the primers, suggesting significant differences in the detection rates of B cell lymphomas by the 3 primers. The detection rate was increased to 83.9% by combining the results by P31 and P2A primers. No positivity was found in the proliferative reaction tissues. CONCLUSION: Primers from IgH FR3 region genes are more sensitive than that from the FR1 and FR2 regions in the detection of gene rearrangement in paraffin-embedded lymphoma tissues. The detection rates can be increased by combining the results with the primers for IgH FR3 with that of FR2.

[Primary diffuse large B-cell lymphoma of the heart: a clinicopathological study].

OBJECTIVE: To define the clinicopathological features of primary cardiac large B-cell lymphoma. METHOD: A case of primary cardiac large B-cell lymphoma was studied with conventional histopathological and immunohistochemical staining in combination with literature review. RESULTS: The lesion appeared to originate in the right atrium and involved the venae cavae and the left atrium. Microscopic examination showed diffuse proliferation of large atypical lymphocytes with abundant cytoplasm, vestiealer nuelei, thick nuclear membrane and conspicuous nucleoli. Giant tumor cells scattered in the lesion. The neoplastic cells were positive for CD20 and CD79a. CONCLUSION: Primary cardiac lymphoma is extremely rare, and its pathogenesis remains unclear. With non-specific clinical manifestations, the majority of primary cardiac lymphomas are of B-cell lineage and a bad prognosis.

[Value of combinational detection by IgH and IgL primers in improving detection rate of lymphoma gene in paraffin-embedded tissue].

BACKGROUND & OBJECTIVE: Clonality detection through amplifying immunoglobulin heavy chain (IgH) by polymerase chain reaction (PCR) is a useful tool in diagnosis of lymphoma, but the false negative rate is high, especially in paraffin-embedded tissues. This study was to explore the value of tumor tissue microdissection and combinational detection of IgH and immunoglobulin light chain (Ig kappa or Ig lambda) in diagnosis of non-Hodgkin's lymphoma (NHL). METHODS: Two pairs of conventional primers for IgH and T-cell receptor gamma (TCRgamma), 2 novel designed pairs of primers for Ig kappa and Ig lambda were used to detect 58 paraffin-embedded blocks, which had been diagnosed by pathology and histochemistry. Of the 58 cases of lymph node tissues, 39 were B-cell lymphoma, 16 were T-cell lymphoma, and 3 were reactive proliferative lymph node tissue. Lymphoma cell lines DG75 and Jurkat were used as control. RESULTS: The positive rates of IgH primers (P1) and IgL primers (P kappa/P lambda) were 79.5% and 71.8% in the 39 cases of B-cell lymphoma (P>0.05), 6.3% and 12.5% in the 16 cases of T-cell lymphoma, respectively. The positive rate was greatly increased to 92.3% in combinationally detecting the primers for IgH and P kappa/P lambda. There was no positive detection among the reactive proliferative lymph node tissues. CONCLUSION: B-cell lymphoma detection rate can be significantly improved by the combination of IgH and IgL gene rearrangement primers, which provides efficient assistant method for the diagnosis and differential diagnosis of lymphoma.

[Detection of bcl-2/IgH gene rearrangement in diffuse large B cell lymphoma by hemi-nested PCR].

OBJECTIVES: To explore a sensitive and specific method for detection of bcl-2/IgH gene rearrangement in diffuse large B cell lymphoma (DLBCL), and verify the credibility of the established method. METHODS: bcl-2/IgH hemi-nested PCR primers were designed using the professional primer design software. Fifty-two samples of pathologically diagnosed DLBCL and 10 fresh tonsil tissues were amplified using hemi-nested touch down-PCR to detect bcl-2/IgH gene rearrangement. The PCR products were cloned and sequenced. RESULTS: bcl-2/IgH gene rearrangement was detected in 6 of 52 DLBCL samples and 2 of 10 fresh tonsil tissues using one-way method. By using the hemi-nested PCR for the second round amplification, 5 of DLBCL were positive, but all of the fresh tonsil tissues were negative. The positive PCR products were sequenced and analyzed on the Internet, 3 of 8 cases obtained by one-way method were false positive, 5 positive cases amplified using hemi-nested PCR were all bcl-2/IgH gene rearrangement. PCR products of 3 false positive cases were homologous to BAC331191 and LLNLR-245D11 in human chromosome 19 and RP11-498P10 in chromosome 1. CONCLUSION: There are false positive results using common primers for detecting bcl-2/IgH gene rearrangement. The mechanism may be that highly homologous sequences to human genome exist in commonly used primers. The specificity of the diagnosis could be improved by hemi-nested PCR using the combination of primers we designed and the traditional ones.

[Explore the origin of H/RS cells on protein and gene].

OBJECTIVE: To explore the origin and clonality of H/RS cells. METHODS: Immunohistochemical method was used to detect the expression of B-cell-specific activator protein (BSAP) and CD(20) in 33 paraffin-embedded tissues of classical Hodgkin lymphoma (cHL). IgH gene rearrangement was detected in 33 paraffin-embedded cHL tissue and 6 microsectioned H/RS cell samples. The PCR products of a case of cHL and its microsectioned cells were sequenced. RESULTS: H/RS cells were positive for BSAP in 30 of 33 (90.91%) cHL cases and positive for CD(20) in 10/33 (30.30%) cases. There was a significant difference between the expression of BSAP and CD(20) in H/RS cells (P = 0.000). BSAP and CD(20) were positive in almost all B cells of lymph node reactive hyperplasia and malignant cells in B-cell lymphomas while were negative in all malignant cells of T-cell lymphomas. 16 of 33 cHL were positive for gene rearrangement, and microsectioned H/RS cells in 14 of 19 tubes displayed clonal bands of rearrangement. There was no significant difference among the rearrangement rates in tubes containing different numbers of H/RS cells (P = 0.280). Sequencing analyses of the PCR products from both paraffin-embedded tissue and microsection of the same patient revealed the rearranged V segments, but the sequences were not identical. CONCLUSION: H/RS cells were originated from B cells of different differentiation stage.

[Unspecified peripheral T cell lymphoma with distinct lymphoid follicules].

OBJECTIVE: To investigate the morphological features and immunophenotype of unspecified peripheral T cell lymphoma with distinct lymphoid follicular growth pattern. METHODS: Three cases of peripheral T cell lymphoma with special pathohistological features were collected. Morphologic analysis and immunohistochemical staining for CD3, CD45RO, CD43, CD20, CD79a, cyclinD1, bcl-2, CD4, CD8 and S-100 were performed. PCR was used to study TCR gamma gene rearrangements. RESULTS: The main symptoms of all the three patients with the primary sites of cervix and lower jaw. There were intermittent fever and skin rashes in the course of the disease. Morphological study showed lymphoid follicular reactive hyperplasia, mantle zone disappear, prominent infiltration of marginal zones by medium-sized tumor cells with clear cytoplasm and significant nuclear atypia. The immunophenotypic profile confirmed that they were T cell lymphomas. TCR gamma gene rearrangements were found in all the three patients. CONCLUSION: In some unspecified peripheral T cell lymphomas, the distinct follicular growth pattern and incomplete effacement of the lymph node architecture make it necessary to differentiate them from reactive hyperplasia, marginal zone B cell lymphoma, follicular B cell lymphoma and mantle cell lymphoma.