Gene Rearrangement Analysis Research Articles

Clues to pathogenesis of Waldenström macroglobulinemia and immunoglobulin M monoclonal gammopathy of undetermined significance provided by analysis of immunoglobulin heavy chain gene rearrangement and clustering of B-cell receptors

We characterized immunoglobulin heavy chain (IGH) gene rearrangements and searched for clusters of stereotyped B-cell receptors in 123 patients with Waldenström macroglobulinemia (WM; n = 59) or immunoglobulin M monoclonal gammopathy of undetermined significance (IgM-MGUS) (n = 64). A productive monoclonal IGHV-D-J rearrangement was obtained in 99/123 patients (80%). Immunoglobulin heavy chain variable (IGHV) genes were mutated in 94/99 patients (95%) with a median somatic hypermutation rate of 6.7% (2.1–14.5). Compared with the normal B-cell repertoire, patients with WM/IgM-MGUS showed an over-representation of the IGHV3 subgroup (83% vs. 55%, p < 0.0001) and an under-representation of IGHV1 (7% vs. 14%, p = 0.04) and IGHV4 (7% vs. 23%, p = 0.0001) subgroups. At the gene level, in WM/IgM-MGUS there was an over-representation of IGHV3-23 (24% vs. 12%, p = 0.0003), IGHV3-64 (3% vs. < 1%, p = 0.003), IGHV3-7 (12% vs. 4%, p = 0.0001) and IGHV3-74 (9% vs. 2%, p < 0.0001), while IGHV4-39 was never used (0 vs. 5%, p = 0.03). Intra-WM/IgM-MGUS search for HCDR3 similarity showed no association fulfilling criteria for stereotyped receptors. WM/IgM-MGUS sequences were unrelated to known chronic lymphocytic leukemia (CLL), splenic marginal zone lymphoma (SMZL) or mantle cell lymphoma (MCL) subsets. In conclusion, the IGHV gene usage in WM and IgM-MGUS is remarkably biased as compared to the normal B-cell repertoire. WM and IgM-MGUS-specific HCDR3 clusters do not occur with a frequency detectable with currently available databases, not supporting a B-cell receptor-driven pathogenesis in WM and IgM-MGUS.

Intraclonal Heterogeneity in Concomitant Monoclonal Lymphocyte and Plasma Cell Populations: Combining Flow Cytometric Cell Sorting With Molecular Monoclonality Profiling

Flow cytometric cell sorting combined with molecular gene rearrangement analysis can assist in further characterizing simultaneously occurring, phenotypically distinct, monoclonal B-lymphoid and monoclonal plasma cell populations that express immunoglobulin of the same light chain. We previously established monoclonality profiles for lymphoid and plasma cell populations of lymphoplasmacytic lymphoma (LPL) bone marrow aspirates by using flow cytometric cell sorting and subsequent monoclonal gene rearrangement analysis. Our findings demonstrated that related genetic processes are less likely than unrelated genetic processes. Here, we demonstrated the utility of cell sorting combined with gene rearrangement (both immunoglobulin IgH and IgK) and IgVH sequence analysis as well as plasma cell targeted fluorescence in situ hybridization analysis in clinical cases of presumed Waldenström macroglobulinemia/LPL in which multiple distinct B-cell and plasma cell populations were identified. Combining cell sorting with subsequent molecular analysis can provide proof of identical monoclonal genotype for Waldenström macroglobulinemia/LPL and nonidentical distinct lymphoid and plasma cell populations in the clinical setting. Understanding how many clonal processes (molecular profiles) are present can help guide patient monitoring throughout treatment and potentially identify patients with worse outcomes.

Identification of EGFR mutation, KRAS mutation, and ALK gene rearrangement in cytological specimens of primary and metastatic lung adenocarcinoma

The identification of molecular alterations has an important therapeutic implication in patients with lung adenocarcinomas. In the current study, the authors evaluated their experience with the identification of epidermal growth factor receptor (EGFR), Kirsten rat sarcoma viral oncogene homolog (KRAS) mutation, and anaplastic lymphoma kinase (ALK) gene rearrangement using cytological specimens of primary and metastatic lung adenocarcinoma. A total of 54 cases of lung adenocarcinomas (11 primary and 43 metastatic tumors) in which molecular tests were performed were retrieved. Molecular tests were performed on the cell block material of 19 effusions and 35 fine-needle aspirates. EGFR mutation was evaluated by polymerase chain reaction sequencing analysis of exons 18, 19, 20, and 21. KRAS mutation was tested using polymerase chain reaction-single-strand conformational polymorphism analysis of codons 12 and 13. ALK gene rearrangement was evaluated by fluorescence in situ hybridization using an ALK break apart probe. Molecular tests were successful in 49 of 54 cases (91%). Evaluation of EGFR mutation, KRAS mutation, and ALK gene rearrangement were performed in 49 cases, 14 cases, and 22 cases, respectively. EGFR mutations were found in 14 of 49 cases (29%), including 5 primary and 9 metastatic tumors. Three metastatic/recurrent adenocarcinomas demonstrated an additional EGFR T790M mutation that was not identified in the original specimens. KRAS mutation was detected in 3 of 14 cases (21%) including 1 primary and 2 metastatic tumors. ALK gene rearrangement was evident in 3 of 22 cases (14%), all of which were metastatic tumors. The results of the current study have demonstrated the feasibility of using cytological specimens for EGFR mutation, KRAS mutation, and ALK gene rearrangement analysis. Repeating molecular testing in metastatic/recurrent lung adenocarcinomas may uncover newly acquired molecular alterations.

Aggressive natural killer-cell leukemia with jaundice and spontaneous splenic rupture: a case report and review of the literature

Aggressive natural killer cell leukemia/lymphoma (ANKL) is a rare aggressive form of NK-cell neoplasm. We report an uncommon case of 36-year-old male who showed jaundice and spontaneous splenic rupture. The diagnosis was established by the biopsy of liver and spleen. The monomorphous medium-size neoplastic cells infiltrated into portal areas and sinus of liver as well as the cords and sinus of the spleen. Necrosis, mitotic figures and significant apoptosis could be seen easily. These neoplastic cells demonstrated a typical immunophenotype of CD3ε+, CD56+, CD16+, Granzyme B+, TIA-1+. T-cell receptor γ (TCR-γ) gene rearrangement analysis showed germline configuration and the result of in situ hybridization for Epstein-Barr virus-encoded RNA (EBER-ISH) was positive. The patient has undergone an aggressive clinical course and died of multi-organ function failure 14 days later after admission. To the best of our knowledge, this is the first case of ANKL with spontaneous splenic rupture, and we should pay more attention to recognize it.Virtual SlidesThe virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/2048154883890867

Recommendations for the Analysis of ALK Gene Rearrangements in Non–Small-Cell Lung Cancer: A Consensus of the Italian Association of Medical Oncology and the Italian Society of Pathology and Cytopathology

Recent clinical trials led to the approval of crizotinib (PF-02341066; Pfizer) by the U.S. Food and Drug Administration for the treatment of locally advanced or metastatic non-small-cell lung cancer (NSCLC) patients whose tumors are positive for anaplastic lymphoma kinase (ALK) alterations. The European Medicines Agency accepted the regulatory submission of crizotinib for the treatment of these patients. Therefore, ALK gene testing has become mandatory to choose the most appropriate therapy. To help physicians, involved in the management of NSCLC patients to be treated with ALK inhibitors in Italy, the Italian Association of Medical Oncology and the Italian Society of Pathology and Cytopathology identified a large panel of Italian medical oncologists and pathologists that outlined recommendations for ALK testing in NSCLC patients. The guidelines produced include specific information on the target patient population, the biological material for molecular analysis, a section dedicated to the histocytopathologic diagnosis of NSCLC, and the methods for the assessment of ALK alterations that are summarized in this article. Clinicopathologic recommendations were produced to guide the management of NSCLC patients who need to be tested for ALK rearrangements before treatment with ALK inhibitors.

Canine inflamed nonepitheliotropic cutaneous T‐cell lymphoma: a diagnostic conundrum

Cutaneous T-cell lymphoma (CTCL) in dogs is a heterogeneous disease complex, which consists of nonepitheliotropic (NE) and epitheliotropic forms. These lymphomas are readily recognized by the presence of dominant populations of cytologically atypical lymphocytes. The objective of this study was to introduce the key features of inflamed NE-CTCL, which is easily confused with reactive, inflammatory histiocytic disease. Twenty-four dogs (mean age 7.5 years) presented with inflamed NE-CTCL. Lesions presented as nodules, plaques or masses. An initial diagnosis of cutaneous reactive histiocytosis (11 dogs) or histiocytic neoplasia (three dogs) was made by primary pathologists. Lesions were assessed by histology and immunohistochemistry to detect canine leukocyte antigens. Lesional genomic DNA was extracted and gene rearrangement analysis of the T-cell receptor γ locus was assessed. The cutaneous lesions consisted of pleocellular infiltration of the dermis with variable extension into the subcutis. The lesions often surrounded vessels and adnexae. Epitheliotropism was minimal or lacking. Small lymphocytes, plasma cells and intermediate to large, cytologically atypical lymphocytes were scattered between prominent histiocytic infiltrates. Atypical lymphocytes often had marked variation in the intensity of CD3 expression. Molecular clonality analysis of the T-cell receptor γ locus revealed clonal expansion of T cells in 22 of 23 dogs tested. The recognition of inflamed NE-CTCL and its differentiation from cutaneous reactive histiocytosis depends on careful assessment of lymphocyte morphology and immunostaining patterns. Confirmation of the diagnosis is best accomplished by T-cell antigen receptor gene rearrangement analysis.

Nævus géant congénital

A hallmark of lymphoid malignancies is the presence of a monoclonal lymphocyte population. Monoclonality of B- and T-cell populations can be established through immunoglobulin (IG) or T-cell receptor (TCR) gene rearrangement analysis, respectively. The biological rationale of IG and TCR gene rearrangement analysis is that due to the extensive combinatorial repertoire made possible by V(D)J recombination in lymphocytes, it is unlikely that any substantive lymphocyte population would share the same IG or TCR gene rearrangement pattern unless there is an underlying neoplastic or reactive origin. Modern IG and TCR gene rearrangement analysis is typically performed by polymerase chain reaction (PCR) using commercially available primer sets followed by gel capillary electrophoresis. This process is highly sensitive in the detection of nearly all lymphoid malignancies. Several pitfalls and limitations, both biological and technical, apply to IG/TCR gene rearrangement analysis, but these can be minimised with high quality controls, performance of assays in duplicate, and adherence to strict criteria for interpreting and reporting results. Next generation sequencing (NGS) will likely replace PCR based methods of IG/TCR gene rearrangement analysis but is not yet widespread due to the absence of standardised protocols and multicentre validation.

The analysis of ALK gene rearrangement by fluorescence in situ hybridisation in non-small cel lung cancer patients

Introduction ALK gene rearrangement is observed in a small subset (3–7%) of non-small cell lung cancer (NSCLC) patients. The efficacy of crizotinib was shown in lung cancer patients harbouring ALK rearrangement. Nowadays, the analysis of ALK gene rearrangement is added to molecular examination of predictive factors.Aim of the studyThe frequency of ALK gene rearrangement as well as the type of its irregularity was analysed by fluorescence in situ hybridisation (FISH) in tissue samples from NSCLC patients.Material and methodsThe ALK gene rearrangement was analysed in 71 samples including 53 histological and 18 cytological samples. The analysis could be performed in 56 cases (78.87%), significantly more frequently in histological than in cytological materials. The encountered problem with ALK rearrangement diagnosis resulted from the scarcity of tumour cells in cytological samples, high background fluorescence noises and fragmentation of cell nuclei.ResultsThe normal ALK copy number without gene rearrangement was observed in 26 (36.62%) patients ALK gene polysomy without gene rearrangement was observed in 25 (35.21%) samples while in 3 (4.23%) samples ALK gene amplification was found. ALK gene rearrangement was observed in 2 (2.82%) samples from males, while in the first case the rearrangement coexisted with ALK amplification. In the second case, signet-ring tumour cells were found during histopathological examination and this patient was successfully treated with crizotinib with partial remission lasting 16 months.ConclusionsFISH is a useful technique for ALK gene rearrangement analysis which allows us to specify the type of gene irregularities. ALK gene examination could be performed in histological as well as cytological (cellblocks) samples, but obtaining a reliable result in cytological samples depends on the cellularity of examined materials.

The Role of Molecular Pathology in the Diagnosis of Cutaneous Lymphomas

Primary cutaneous lymphomas can be difficult to be distinguished from reactive mimics, even when integrating histologic, immunophenotypic, and clinical findings. Molecular studies, especially PCR-based antigen receptor gene rearrangement (ARGR) analysis, are frequently useful ancillary studies in the evaluation of cutaneous lymphoproliferations. The biologic basis of ARGR studies is discussed, as well as a comparison of various current protocols. The pitfalls and limitations of ARGR analysis are also highlighted. Recent advances in the understanding of the molecular pathogenesis of various cutaneous lymphomas are discussed. Some of these nascent discoveries may lead to the development of diagnostically useful molecular assays.

Plasmablastic lymphoma of the stomach in an HIV‐negative patient

Plasmablastic lymphoma (PBL) is a rare B-cell neoplasm with an aggressive clinical behavior that predominantly occurs in the oral cavity of human immunodeficiency virus (HIV)-positive patients. However, it has recently been recognized that PBLs can also affect individuals without HIV infection, and suggested that these neoplasms show different clinicopathological characteristics between HIV-positive and -negative patients. Herein we describe a case of gastric PBL in a female HIV-negative patient. The tumor was composed of a diffuse and cohesive proliferation of large neoplastic cells, which resembled immunoblasts or plasmablasts with a starry sky appearance. Immunophenotypically, the neoplastic cells were diffusely positive for CD138, MUM1, IgM, and BOB-1, and negative for CK, LCA, CD3, CD20, CD79a, Pax5, kappa, lambda, CD30, ALK, S-100, HMB-45, MPO, and HHV-8. The MIB-1 index was nearly 100%. Epstein-Barr virus-encoded RNA in situ hybridization was negative. A monoclonal immunoglobulin heavy chain gene rearrangement was detected in polymerase chain reaction (PCR) and heteroduplex analyses. A combination of PCR-based analysis of immunoglobulin gene rearrangement and immunohistochemistry can be useful to substantiate the diagnosis by utilizing routine paraffin-embedded tissue sections, because PBL in the setting of extra-oral localization and immunocompetence is a diagnostic challenge, given its rarity, morphology, and absence of CD20 expression.

Miliarial‐type perifollicular B‐cell pseudolymphoma (lymphocytoma cutis): a misleading eruption in two women

Disseminated miliarial-type lymphocytoma cutis is a rare clinicopathologic subtype of lymphocytoma, characterized by numerous translucent micropapules and located on the head and neck. We describe here the clinical, histological and immunological features of miliarial-type perifollicular B-cell pseudolymphoma in two women aged 32 and 49 years presenting with numerous 1-2 mm translucent papules on the head and neck. Microscopic examination revealed features typical of a miniature lymphocytoma cutis with a superficial nodular infiltrate housing small well-circumscribed germinal centers containing tingible body macrophages and surrounded by a distinct mantle zone. The immunohistological profile was also typical of lymphocytoma cutis, and polymerase chain reaction analysis of the IgH gene rearrangement did not show any clonal B-cell population. The lesions resolved spontaneously in one case and improved after treatment with hydroxychloroquine in the second patient. The presentation of this subtype of lymphocytoma is a formidable clinical diagnostic challenge. Rosacea, sarcoidosis, democidiosis, lupus miliaris disseminatus faciei and steroid acne are easy to exclude on the basis of histological profile. However, the miliarial form of primary cutaneous center lymphoma is difficult to rule out. Dermatologists and dermatopathologists should be aware of this unusual form of lymphocytoma cutis, which can be misleading during clinical diagnosis.

Utility of NUT gene expression and rearrangement in diagnosis of NUT midline carcinoma in upper respiratory tract

To investigate the importance of expression of the NUT gene and its rearrangement in diagnosing NUT midline carcinoma (NMC) of the upper respiratory tract; and to evaluate the prevalence, histological features and differential diagnosis of NMC of the upper respiratory tract. One-hundred and sixty-three small cell malignant tumors of the upper respiratory tract were reviewed at the Beijing Tongren Hospital, Capital Medical University over a 20-year period. These cases included poorly-differentiated squamous cell carcinomas (n = 31), undifferentiated carcinoma (n = 1), non-keratizing undifferentiated nasopharyneal carcinomas (n = 60), small cell neuroendocrine carcinomas (n = 6) and non-epithelial small round cell malignant tumors (n = 65). The clinical and pathologic features were investigated. All cases were subjected to Epstein-Barr virus encoded RNA (EBER) in situ hybridization and NUT monoclonal antibody immunohistochemical staining. Cases positive for NUT immunohistochemistry and negative for EBER in situ hybridization were submitted for fluorescent in situ hybridization (FISH) for rearrangements in both BRD4 and NUT genes, and immunohistochemical staining for a set of cytokeratins (AE1/AE3, CK7, CK8), p63,and neuroendocrine markers (NSE, Syn, CgA, S-100 protein, CD56). Three cases of poorly-differentiated squamous cell carcinomas and one case of undifferentiated carcinoma showed diffuse nuclear immunohistochemical staining with antibody against NUT. These positive cases approximately accounted for 12.5% (4/32) of this group, 4.1% (4/98) of the malignant epithelial carcinomas and 2.5% (4/163) of all small round cell malignant tumors in the study. The age of these patients were 42 - 59 years. Other groups were all negative for NUT immunohistochemistry. These four cases also stained for antibodies against cytokeratins and p63, but were negative for neuroendocrine markers and not associated with EBV infection. Only two of these four cases showed rearrangements of the NUT and BRD4 genes by FISH. These two patients died within one year. The other two patients that did not demonstrate NUT rearrangement by FISH were alive and did not have an aggressive clinical course, surviving 40 and 12 months respectively. NMC is a rare small round cell malignant tumor in the upper respiratory tract. Only in the groups of primary poorly differentiated squamous cell carcinoma and undifferentiated carcinoma were positive for NUT immunohistochemical staining and NUT rearrangement by FISH. NMC typically occurs in midline organs, and affects the sinonasal tract. It is not associated with EBV infection. There is difference in the clinical course and prognosis among NMC patients. NUT immunohistochemical staining and NUT gene rearrangement analysis can differentiate NMC from other small cell tumors in the upper respiratory tract.

Analysis of T-cell receptor-γ gene rearrangements using heteroduplex analysis by high-resolution microcapillary electrophoresis

Determination of T-cell clonality has an important additional value for diagnosis of T-cell lymphomas. Various molecular methods have been developed, including polymerase chain reaction (PCR) of T-cell receptor γ (TCRγ). The detection of PCR products usually relies commonly on either GeneScan (GS) analysis or heteroduplex (HD) analysis by polyacrylamide gel electrophoresis (PAGE). These techniques have their disadvantages, being relatively time-consuming and laborious or requiring expensive equipment. Here, we propose an alternative method that combines multiplex PCR and HD analysis by microcapillary electrophoresis (ME) on the Agilent 2100 Bioanalyzer. The sensitivity of the method was determined with clonal PEER T-cell line DNA dilution in polyclonal DNA and was evaluated as 1–5%. Fifty-three samples from patients with T-cell lymphoproliferative disorders were analyzed by HD analysis using ME and GS analyses. Comparison of the two techniques showed them to be highly concordant (93% similarity). The rate of clonality detection by GS analysis was higher than HD analysis by ME, but none of the discordant patients (n=5) has yet developed lymphoma. HD analysis by ME to reveal TCRγ gene rearrangements in clinical specimens was consistent with clinical data and the outcome of patients. Detection of T-cell clonality by HD analysis with ME is sensitive, practical, safe and represents a potential alternative to PAGE and GS analysis.

Diagnostic Usefulness of Genomic Breakpoint Analysis of Various Gene Rearrangements in Acute Leukemias: A Perspective of Long Distance– or Long Distance Inverse-PCR–based Approaches

Diagnostic Usefulness of Genomic Breakpoint Analysis of Various Gene Rearrangements in Acute Leukemias: A Perspective of Long Distance– or Long Distance Inverse-PCR–based Approaches

Clinicopathologic features of gastrointestinal tract involvement of anaplastic large cell lymphoma.

To investigate the clinicopathological characteristics of gastrointestinal tract involvement of anaplastic large cell lymphoma (ALCL). The clinicopathological features of four patients with ALCL that involved gastrointestinal tract were retrospectively analyzed using immunohistochemical study, T-cell receptor gene rearrangement analysis, and evaluation for Epstein Barr virus infection status. Most tumor cells in all these four cases are large and highly pleomorphic, and all four cases were classified as the common pattern ALCL. Tumor cells in all four tumors expressed CD30, and expressed at least one cytotoxic maker. Two patients were confirmed to be with anaplastic lymphoma kinase (ALK)-positive ALCL, and four patients were negative during in situ hybridization for Epstein-Barr virus-encoded RNA but showed clonal T-cell receptor gene rearrangement. Gastrointestinal tract involvement of ALCL has the unique clinicopathological features.

Composite Lymphocyte-Rich Thymoma and Peripheral T-Cell Lymphoma Not Otherwise Specified: Case Report and Literature Review

The simultaneous occurrence of thymoma and peripheral T-cell lymphoma not otherwise specified (PTCL-NOS) has not been previously reported, to our knowledge. We describe a 59-year-old ethnic Filipina woman with myasthenia gravis who was found to harbor an invasive lymphocyte-rich thymoma (World Health Organization [WHO] type B1). Subsequent pathologic examination of her mediastinal and abdominal lymph nodes revealed concurrent PTCL-NOS. A bone marrow examination revealed T-cell lymphoma, which was confirmed by flow cytometric and T-cell receptor gene rearrangement analysis. * NHL : non-Hodgkin lymphoma WBC : white blood cell PTCL-NOS : peripheral T-cell lymphoma not otherwise specified MRI : magnetic resonance imaging CT : computed tomographic WHO : World Health Organization HTLV-1 : human T-cell leukemia virus type 1 HTLV-2 : human T-cell leukemia virus type 2 PCR : polymerase chain reaction TCR : T-cell receptor CML : chronic myelogenous leukemia

The Inference of Phased Haplotypes for the Immunoglobulin H Chain V Region Gene Loci by Analysis of VDJ Gene Rearrangements

The existence of many highly similar genes in the lymphocyte receptor gene loci makes them difficult to investigate, and the determination of phased "haplotypes" has been particularly problematic. However, V(D)J gene rearrangements provide an opportunity to infer the association of Ig genes along the chromosomes. The chromosomal distribution of H chain genes in an Ig genotype can be inferred through analysis of VDJ rearrangements in individuals who are heterozygous at points within the IGH locus. We analyzed VDJ rearrangements from 44 individuals for whom sufficient unique rearrangements were available to allow comprehensive genotyping. Nine individuals were identified who were heterozygous at the IGHJ6 locus and for whom sufficient suitable VDJ rearrangements were available to allow comprehensive haplotyping. Each of the 18 resulting IGHV│IGHD│IGHJ haplotypes was unique. Apparent deletion polymorphisms were seen that involved as many as four contiguous, functional IGHV genes. Two deletion polymorphisms involving multiple contiguous IGHD genes were also inferred. Three previously unidentified gene duplications were detected, where two sequences recognized as allelic variants of a single gene were both inferred to be on a single chromosome. Phased genomic data brings clarity to the study of the contribution of each gene to the available repertoire of rearranged VDJ genes. Analysis of rearrangement frequencies suggests that particular genes may have substantially different yet predictable propensities for rearrangement within different haplotypes. Together with data highlighting the extent of haplotypic variation within the population, this suggests that there may be substantial variability in the available Ab repertoires of different individuals.

The added value of immunoglobulin Kappa light chain gene (IGK) rearrangement analysis in suspected B-cell lymphomas: three illustrative cases

Immunoglobulin Kappa light chain gene (IGK) rearrangements are important complementary PCR targets for clonality assessment in mature B-cell proliferations in which detection of clonal VH-JH gene rearrangements fails. Failure to amplify VH-JH rearrangements is mainly attributable to somatic hypermutation. Detection of clonal IGK rearrangements is most relevant in the diagnosis of germinal center (GC) and post-GC B-cell lymphomas that are under a heavy somatic mutation process. Here we present three cases in which histology and immunophenotype of the tissue samples at time of diagnosis were inconclusive. PCR-based B-cell clonality assessment was performed using the standardized BIOMED-2 multiplex PCR protocols and Genescan analysis. No clonal VH-JH rearrangements were observed. Detection of a clonal IGK product in each of the three suspected cases supported the clonal origin of the B-cell proliferations. Interestingly, only rearrangements involving the Kde element were detected. Based in the clonal IGK-PCR result, a definitive diagnosis of follicular lymphoma (case 1 and 3) and extranodal marginal zone lymphoma (case 2) was established.

Analysis of BRCA1 Gene Rearrangements in Breast Carcinomas by RT-PCR and ER, PR, HER2NEU Status by IHC and HPE Correlation.

An attempt to analyze invasive ductal carcinomas of the breast, based on the histopathological sub classification and grading, the hormonal status on immunohistochemistry (IHC) and the BRCA1 gene expression. Fifty patients were selected from the Kancheepuram area on the basis of their admissions to the Surgical Out-Patients Wing of the Meenakshi Medical College and Hospital over a period of 3 years from 2008-2011. Among the fifty patients who were selected in the case series, the most common age group was 41-60 years (23 patients). The grade 3 tumours were the commonest. An immunohistochemical evaluation of the hormone receptors revealed most of the tumours to be of the luminal subtype. BRCA1 gene mutation analysis showed that all the 50 cases of breast cancer elaborated an up-regulation of the selected base-pair fragment. Among the various determinants of breast cancer development, this study proved that age, the histological tumour grade and the immunohistochemical analysis also formed the important factors that aided in the diagnosis of breast cancers and their classifications. Also, genetic studies could provide useful insights by helping in the determination of the presence or the absence of gene mutations, which could revolutionize the treatment. This would be possible by using gene therapy in the future.

Prognostic significance of MYC, BCL2, and BCL6 rearrangements in patients with diffuse large B‐cell lymphoma treated with cyclophosphamide, doxorubicin, vincristine, and prednisone plus rituximab

Diffuse large B-cell lymphomas (DLBCLs) are a biologically heterogeneous group in which various gene alterations have been reported. The aim of this study was to investigate the frequency and prognostic impact of BCL2, BCL6, and MYC rearrangements in cyclophosphamide, doxorubicin, vincristine, and prednisone plus rituximab (R-CHOP)-treated DLBCL cases. Tissue microarrays were constructed from 239 cases of DLBCL, and the expressions of CD10, BCL6, MUM1/IRF4, and BCL2 were evaluated by immunohistochemistry. MYC, BCL2, and BCL6 rearrangements were investigated by interphase fluorescence in situ hybridization on tissue microarrays. Survival analysis was constructed from 145 R-CHOP-treated patients. MYC, BCL2, and BCL6 rearrangements were detected in 14 (6%), 36 (15%), and 69 (29%) of 239 DLBCL patients. Double or triple rearrangements were detected in 7 (3%) of 239 DLBCL cases. Of these, 4 had BCL2 and MYC, 2 had BCL6 and MYC, and 1 had BCL2, BCL6, and MYC rearrangements. The prognosis of these cases was extremely poor, with a median survival of 9 months. MYC rearrangement was associated with significantly worse overall survival (P = .01), especially for the cases with GC phenotype (P = .009). BCL6 rearrangement also predicted significantly shorter overall survival (P = .04), especially for the non-GC phenotype (P = .03). BCL2 rearrangement had no prognostic impact on outcome. International Prognostic Index (P = .004) and MYC rearrangement (P = .009) were independent poor prognostic factors. Analysis of MYC gene rearrangement along with BCL2 and BCL6 is critical in identifying high-risk patients with poor prognosis.