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T C Diss

Publications and source records attributed to T C Diss.

At least 55 records · Page 3Linked to original sources
PubMed1996

Detection of Helicobacter pylori in gastric biopsy and resection specimens.

AIMS: To compare the sensitivity of detecting Helicobacter pylori in gastric biopsy and resection specimens using tinctorial and silver impregnation stains, immunohistochemistry and the polymerase chain reaction (PCR). METHODS: Formalin fixed, paraffin wax embedded tissue from 33 gastric biopsy specimens (26 showing chronic gastritis and seven showing low grade mucosa associated lymphoid tissue (MALT) lymphoma) together with blocks of uninvolved mucosa from gastrectomy specimens for MALT lymphoma (five cases) were studied. Consecutive sections were stained using haematoxylin and eosin, Giemsa, the Warthin-Starry silver stain, and a polyclonal antibody directed against H pylori using an immunoperoxidase technique following heat induced antigen retrieval. PCR analysis of DNA extracted from a further section was carried out using primers which amplified a 411 base pair fragment of the urease A gene. RESULTS: H pylori was detected in 14 (37%) sections stained with haematoxylin and eosin, 21 (55%) with Giemsa, 23 (61%) with Warthin-Starry, and 25 (66%) stained with the antibody. Seventeen (45%) cases were positive on PCR. Immunohistochemistry was positive in all cases in which H pylori was detected by other methods. CONCLUSION: Immunohistochemistry using an immunoperoxidase technique following heat induced antigen retrieval for detecting H pylori in gastric biopsy and resection specimens is highly sensitive and easy to use.

Base Sequence↗
PubMed1996

Ongoing mutation in MALT lymphoma immunoglobulin gene suggests that antigen stimulation plays a role in the clonal expansion.

Indirect antigenic stimulation by H. pylori-specific T cells is implicated in the development of low-grade gastric lymphoma of mucosa-associated lymphoid tissue (MALT), however, the role of direct antigen stimulation is unknown. To study the role of direct antigen stimulation in MALT lymphomagenesis and its relationship with the pathogenesis of distinct pathological lesions, which represent different stages of the tumour progression, we cloned and sequenced the rearranged immunoglobulin (Ig) heavy chain gene in three low-grade (two from the lung, one from the stomach) and one high-grade (from the stomach) cases. In the low-grade gastric case, we studied the Ig sequence in primary as well as its disseminated and recurrent tumours. In the high-grade gastric case, we analysed the Ig sequence in tumour cell populations microdissected from the residual diffuse low-grade lesions, diffuse high-grade areas from follicles colonized by high-grade blasts. Compared with the published germline sequences, the heavy chain variable (VH) genes of three MALT lymphomas, in which the putative germline was identified, contained frequent somatic mutations, showing a much higher ratio of replacement/silent mutations in the complementarity determining regions (CDRs) than the framework regions (FRs). Ongoing mutation as indicated by intraclonal variation of the Ig sequence clearly existed in low-grade tumour including its dissemination and recurrence, but was not evident in high-grade tumour cell populations including those microdissected from independent colonized follicles. In addition, the germlines of VH genes used by the three MALT lymphomas are frequently found in autoreactive antibodies. Our results suggest that MALT lymphoma derives from postgerminal centre memory B cells, possibly autoreactive B cell clones, and that direct antigen stimulation may play an important role in the clonal expansion of low-grade MALT lymphoma.

Animals↗
PubMed1995

Immunoglobulin gene rearrangements in lymphoplasmacytic infiltrates of labial salivary glands in Sjögren's syndrome. A possible predictor of lymphoma development.

OBJECTIVES: Sjögren's syndrome is an autoimmune disorder in which patients have a well-recognized risk of developing malignant lymphoma. Although some clinical parameters may herald the onset of lymphoma, few reliable histologic or molecular markers are available that predict progression to a malignant lymphoproliferative disorder. The purpose of this study was to identify the prevalence of immunoglobulin heavy chain monoclonality in labial gland biopsies of patients with Sjögren's syndrome and to compare this to clinical outcome. STUDY DESIGN: The polymerase chain reaction was applied to 76 sequential labial salivary gland biopsies from patients under investigation for Sjögren's syndrome. A seminested polymerase chain reaction technique was used on DNA extracted from formalin-fixed, paraffin-embedded tissue to amplify the V-D-J region of the immunoglobulin heavy chain gene. Thirty-four randomly selected labial salivary glands that showed nonspecific sialadenitis from patients without Sjögren's syndrome were used as controls. RESULTS: Monoclonality, as defined by a single band on polyacrylamide gel electrophoresis was detected in 11 cases (14.5%). Of cases that showed monoclonality, four patients were subsequently diagnosed with extrasalivary lymphoma. In each case the rearranged bands in the lip biopsy and the lymphoma were the same size. In one patient who later developed lymphoma, a monoclonal rearranged immunoglobulin band was not identified. In addition, no cases of the translocation t(14;18) were identified by polymerase chain reaction in any of the lip biopsies showing heavy chain monoclonality or in any of the extrasalivary gland lymphomas. CONCLUSIONS: These results suggest that monoclonal immunoglobulin heavy chain gene rearrangements are a relatively common finding in patients with Sjögren's syndrome and may prove to be a useful marker for predicting the progression to, and early detection of malignant lymphoma.

Adolescent↗
PubMed1995

B-cell monoclonality, Epstein Barr virus, and t(14;18) in myoepithelial sialadenitis and low-grade B-cell MALT lymphoma of the parotid gland.

Low-grade mucosa-associated lymphoid tissue (MALT) type B-cell lymphomas of the salivary gland arise in a background of myoepithelial sialadenitis (MESA), usually in association with Sjögren's syndrome. The distinction between benign MESA and early lymphoma has proved difficult using histological criteria alone and the significance of B-cell monoclonality in this respect is controversial. We have used immunohistochemistry and polymerase chain reaction (PCR) amplification of immunoglobulin heavy-chain VDJ regions to assess clonality in biopsies from 45 patients with lymphoid infiltration of the parotid. Sequential biopsies spanning 3-18 years were available from seven patients, three of whom had developed disseminated nodal B-cell lymphoma. In light of previous studies, each biopsy was additionally analyzed for the presence of t(14;18) and Epstein Barr Virus (EBV) DNA using PCR. Monoclonality was detected in 34/45 cases. Comparison of histology with clonality confirmed earlier suggestions that the emergence of an identifiable population of centrocyte-like B cells around ducts or epithelial islands correlated with monoclonality. In six of seven patients with sequential biopsies PCR fragments of identical size were amplified from each biopsy, suggesting that demonstrable monoclonality in "lymphoepithelial" lymphoproliferative lesions of the salivary gland is indicative of lymphoma. No t(14;18) chromosome translocations were identified; EBV sequences were detected in three of 45 cases.

Adult↗
PubMed1995

Pulmonary B-cell non-Hodgkin's lymphomas. The value of immunohistochemistry and gene analysis in diagnosis.

We reviewed 45 pulmonary B-cell non-Hodgkin's lymphomas to determine whether their morphology and immunohistochemical features were those of lymphomas arising from mucosa-associated lymphoid tissue (MALT), as described in other sites. The polymerase chain reaction was used to provide further information on clonality. We found that these lymphomas infiltrate the pulmonary interstitium along bronchovascular bundles and interlobular septa, subsequently spilling out into airspaces and finally destroying the alveolar architecture of the lung. Central hyaline sclerosis and vascular infiltration were common features. All lymphomas stained CD20 positive and were accompanied by variable numbers of reactive CD3 positive T-cells. Cytokeratin staining with CAM 5.2 was useful in identifying lymphoepithelial lesions. CD21 staining of follicular dendritic cells revealed germinal centres where they were not recognizable on H & E staining. The polymerase chain reaction was performed on paraffin tissue from 28 patients. Twenty were low grade, of which 12 showed a clonal band and eight showed a polyclonal smear pattern. Eight were high grade, of which one revealed a clonal band. Three produced polyclonal smear patterns and four cases were inadequate samples. In one patient who had lymphoma at a second extranodal site, identical bands were identified, evidence for 'homing' of lymphoid cells towards mucosal epithelium.

Base Sequence↗
PubMed1995

Reactive pulmonary lymphoid disorders.

The two main reactive pulmonary lymphoid disorders are lymphoid interstitial pneumonia and follicular bronchitis/bronchiolitis, both pathological entities with a variety of aetiologies. We reviewed the morphological and immunohistochemical features of 26 cases with one or other of these two diagnoses, to explore the possibility that they represented overlapping patterns of hyperplasia of the bronchopulmonary immune system. The polymerase chain reaction was used to determine the clonality of the infiltrates. Histologically, there was a spectrum of changes with two main components. An interstitial infiltrate of mainly T lymphocytes, plasma cells and histiocytes predominated in lymphoid interstitial pneumonia, whilst lymphoid follicles predominated around airways in follicular bronchitis/bronchiolitis. Classification of the disorder rested on which component the pathologists believed to be dominant. In two cases, histology and immunohistochemistry suggested lymphoma, and in one of these cases this diagnosis was confirmed by the polymerase chain reaction. One case of lymphoid interstitial pneumonia produced three bands. The remainder produced polyclonal patterns when samples were adequate. Clinically, there was no clear difference between patients with the two disorders, or patients with pathological features of both.

Adolescent↗
PubMed1995

A comparative study of the value of immunohistochemistry and the polymerase chain reaction in the diagnosis of follicular lymphoma.

We have compared the value of immunohistochemical and polymerase chain reaction (PCR) techniques in distinguishing follicular lymphoma from follicular hyperplasia in formalin-fixed paraffin-embedded tissues of 41 follicular lymphomas, 15 reactive lymph nodes and 5 reactive tonsils. Immunohistochemistry demonstrated bcl-2 protein in the follicle centre cells of 97% of follicular lymphomas whereas monoclonal immunoglobulin light chain was detected in 83% of cases. Assessing the lowest proliferating follicle of each case by MIB-1 immunostaining, proliferation fractions in the lymphomas varied from 0.5% to 59% (mean 15.6%). Over 80% of lymphomas had proliferation fractions of less than 25%. PCR detected gene rearrangement either at the bcl-2 locus, or at the IgH locus, or at both loci in 32%, 44% and 61% of lymphomas, respectively. The follicle centre cells of the reactive lymph nodes and tonsils were all bcl-2 protein negative and polytypic for kappa and lambda light chains. Proliferation fractions of the lowest proliferating follicle in each reactive case ranged from 30.5% to 86.8% (mean 64.9%). Rearrangements of the bcl-2 or IgH loci were not detected in any reactive case. This study demonstrates that bcl-2 and light chain immunostaining are the most consistently helpful aids to diagnosing follicular lymphoma. A low proliferation fraction also indicates lymphoma but a high proliferation fraction does not exclude the diagnosis. Immunostaining with a combination of anti bcl-2 and MIB 1 antibodies is a sensitive and specific method for identifying follicular lymphoma, is technically simple to perform and easy to interpret. In occasional cases, where immunostaining gives equivocal results, PCR analysis can confirm lymphoma, but a negative result does not exclude the diagnosis.

Antibodies↗
PubMed1995

The polymerase chain reaction in histopathology.

Thanks to the advent of the polymerase chain reaction (PCR) molecular genetic study of histological samples is now a relatively straightforward task and the vast histopathology archives are now open to molecular analysis. In this review we outline technical aspects of PCR analysis of histological material and evaluate its application to the diagnosis and study of genetic, infectious and neoplastic disease. In addition, we describe a number of newly developed methods for the correlation of PCR analysis with histology, which will aid the understanding of the molecular basis of pathological processes.

DNA Primers↗
PubMed1995

The polymerase chain reaction in the demonstration of monoclonality in T cell lymphomas.

AIMS: To evaluate polymerase chain reaction (PCR) amplification of T cell receptor (TCR) beta and gamma chain genes as a means of demonstrating monoclonality in T cell lymphomas using histological samples; to compare the performance of PCR with Southern blot analysis. METHODS: TCR-beta, TCR-gamma and immunoglobulin heavy chain (IGH) genes were analysed using PCR in 55 cases of T cell lymphoma (28 frozen tissue and 27 paraffin wax embedded samples), diagnosed using morphological and immunohistochemical criteria. The 28 frozen samples were subjected to Southern blot analysis using TCR-beta, TCR-gamma and IGH gene probes. Twenty five B cell lymphomas and 21 non-neoplastic lymphoid tissue samples were used as controls. RESULTS: Using TCR-beta PCR, monoclonality was detected in 24 (44%) of 55 T cell lymphomas compared with 43 (78%) of 55 using TCR-gamma PCR and in 82% with both techniques. Five (9%) of 55 T cell lymphomas were IGH PCR positive. None of the non-neoplastic lymphoid control samples were PCR positive. All B cell lymphomas showed a polyclonal pattern with TCR-beta PCR while a single B cell lymphoma was positive using TCR-gamma primers. With TCR-beta PCR, a monoclonal result was seen in 12 (43%) of 28 frozen samples of T cell lymphoma, compared with 23 (82%) of 28 using Southern blot analysis. With TCR-gamma PCR, 19 (68%) of 28 frozen tissue samples were positive, compared with 26 (93%) of 28 using Southern blot analysis. A single case showed IGH rearrangement by Southern blot analysis. CONCLUSION: TCR-gamma PCR should be the method of choice for analysis of clonality in paraffin wax embedded sections of lymphoproliferative lesions, as TCR-beta PCR has a high false negative rate. Southern blot analysis remains the most successful technique when sufficient fresh tissue samples and resources are available.

Base Sequence↗
PubMed1995

Epstein-Barr virus associated lymphoproliferative disorder with fatal involvement of the gastrointestinal tract in an infant.

A case of fatal Epstein-Barr virus (EBV) associated lymphoproliferative disorder is reported in an 11 month old female. Heavy infiltrates of CD20 + and EBV EBER mRNA expressing lymphoid blasts were found to cause a series of ulcers along the entire length of the gastrointestinal tract and there was an ileal perforation. Similar infiltrates were also found in lymph nodes, spleen, and liver. Although blood phenotypic analysis performed shortly before her death revealed a severe decrease in T lymphocytes, neither the patient nor other members of her family had a history of primary or secondary immunodeficiency. EBV infection is common in children. However, such a fatal infection of the virus has not apparently been described previously in infants without pre-established immunodeficiency.

Fatal Outcome↗
PubMed1994

[Low-grade MALT-type non-Hodgkin lymphoma of the stomach with local recurrence 14 years following resection. Demonstration of clonal identity using polymerase-chain-reaction (PCR)].

So-called low grade B-cell lymphomas of MALT type occurring mainly in the gastrointestinal tract but also in the salivary glands, the thyroid and the lungs are indolent neoplasms with a prolonged clinical course and persistent localized disease at the site of origin. This behaviour sets them apart from their nodal counterparts, which are frequently generalized from onset. Their recognition within and their separation from accompanying reactive processes (e.g. chronic gastritis) is important but may be difficult on morphology alone. In the immediate past there have been reports on regression of gastric MALT type lymphomas after eradication of Helicobacter pylori. We observed a 68-year-old male patient who underwent partial gastric resection for persistent ulcer disease in 1979. A histological diagnosis of pseudolymphoma was established at that time. In 1993 he again had gastrointestinal bleeding. Endoscopy revealed ulcerations at the anastomosis. Biopsies showed a monoclonal infiltrate of centrocytoid B-cells with typical lymphoepithelial lesions, suggesting the diagnosis of low grade B-cell lymphoma of MALT type which was seen focally in multiple biopsies randomly taken from the gastric remnant. Review of the 1979 specimen revealed identical lesions. Polymerase chain reaction (PCR) on both specimens demonstrated identical products of rearranged Ig-heavy chain genes, thus confirming the monoclonality and establishing the clonal relationship of both lesions. Staging revealed no extragastric disease. Two courses of chemotherapy did not affect the mucosal infiltrates. Although the patient had been under antacid medication and the presence of Helicobacter pylori could not be demonstrated, antimicrobial treatment was given, after which follow-up biopsies were free of tumor and bacteria after 4 months.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1994

Clonality analysis of defined B-cell populations in archival tissue sections using microdissection and the polymerase chain reaction.

A simple microdissection technique involving the use of a drawn-out glass pipette was developed for isolation of defined cell subsets from tissue sections. Using this technique and the polymerase chain reaction (PCR), clonally rearranged immunoglobulin (Ig) heavy chain genes were reliably amplified in single neoplastic follicles or few hundreds of tumour cells isolated from archival haematoxylin and eosin or immunostained sections of B-cell lymphomas. A polyclonal nature was consistently demonstrated in reactive lymphoid follicles or interfollicular reactive B-cells within the same lymphoma sections. Microdissection of lymphoma cells from within foci of chronic inflammation improved the resolution of tumour-specific PCR products by reducing amplification of background polyclonal B-cell sequences. The combination of microdissection and PCR techniques, therefore, provides an important tool for the investigation of B-cell lymphomas and also allows simple and specific access for other molecular genetic analyses of different cell subsets on tissue sections.

B-Lymphocytes↗
PubMed1994

Primary B-cell mucosa-associated lymphoid tissue lymphoma presenting as a solitary colorectal polyp.

We describe two patients with low-grade and one patient with mixed low- and high-grade B-cell lymphoma of mucosa associated lymphoid tissue (MALT) type arising in the large intestine. In each patient the lesion occurred as a single polyp. Two patients presented with rectal bleeding and in one the lesion was discovered incidentally. The bone marrow was uninvolved in all three cases but in the patient with mixed low- and high-grade lymphoma involvement of mesenteric lymph nodes and liver was found. CT scan revealed no lymphadenopathy or splenomegaly in any of the patients. Two patients remain well 9 and 24 months respectively after polypectomy whereas the patient with mixed low- and high-grade lymphoma died 7 days after hemicolectomy due to cardiac failure. These previously undescribed solitary polypoid MALT lymphomas can closely resemble both benign lymphoid polyposis of the colon and lymphomatous polyposis (mantle cell lymphoma). Because of their different behaviour accurate diagnosis of polypoid MALT lymphoma is important.

Aged↗
PubMed1994

Sources of DNA for detecting B cell monoclonality using PCR.

AIMS: To evaluate the polymerase chain reaction (PCR) demonstration of clonal immunoglobulin heavy chain gene rearrangements using routinely prepared, unstained, and stained formalin fixed, paraffin wax embedded tissue samples. METHODS: Extracts from (a) fresh frozen tissue samples, (b) unstained, and (c) haematoxylin and eosin stained formalin fixed, paraffin wax embedded 5 microns tissue sections from 42 cases of low grade B cell lymphoma, all shown to be monoclonal by Southern blot analysis, were analysed using PCR. Two regions of the variable segment of the immunoglobulin heavy chain gene were amplified (framework 2 to joining region [Fr2/JH] and framework 3 to joining region [Fr3/JH]). Twelve samples of reactive lymphoid tissue were studied as controls. Products from each case were directly compared on polyacrylamide gels. RESULTS: Using both primer combinations, monoclonality was detected in 38 of 42 (90%) cases using fresh material, 37 of 42 (88%) using unstained paraffin wax embedded samples, and in 35 of 42 (83%) cases using haematoxylin and eosin stained sections. No false positive results attributable to fixation, processing, or staining were identified, although the efficiency of amplification using the Fr2/JH primers was significantly reduced. CONCLUSIONS: PCR determination of B cell clonality using paraffin wax embedded material is sufficiently sensitive and reliable for use as a routine diagnostic adjunct to conventional morphological and immunocytochemical assessment of lymphoproliferative disease.

Base Sequence↗
PubMed1994

Multiple PCR analyses on trace amounts of DNA extracted from fresh and paraffin wax embedded tissues after random hexamer primer PCR amplification.

AIM: To establish a simple and reliable polymerase chain reaction (PCR) methodology for random amplification of whole genomic DNA from limited histopathological samples. METHODS: Trace amounts of genomic DNA extracted from fresh tissue and individual lymphoid follicles microdissected from archival paraffin wax tissue sections were amplified using a two-phase PCR protocol with random hexamers as primers (RP-PCR). The randomly amplified DNA samples were used as templates for specific PCR amplifications. To check the fidelity of the RP-PCR, products of the specific PCR amplifications were further analysed by single stranded conformation polymorphism (SSCP) or sequencing. RESULTS: Using a minute fraction of RP-PCR template pool, multiple PCR analyses, including those for beta globin gene, p53 gene (exon 5-6, exon 7, exon 8-9 and exon 7-9), and rearranged immunoglobulin heavy chain gene fragments (VH framework 3 to JH and VH framework 2 to JH) were successfully performed. No artefactual mutations were identified in the products of these specific PCR reactions by SSCP or sequencing when compared with the products from the original DNA. CONCLUSION: This method is simple and reliable, and permits multiple genetic analyses when only a limited amount of tissue is available.

Base Sequence↗
PubMed1993

Regression of primary low-grade B-cell gastric lymphoma of mucosa-associated lymphoid tissue type after eradication of Helicobacter pylori.

Certain features of primary low-grade B-cell gastric lymphoma of mucosa-associated lymphoid tissue (MALT) suggest the tumour is antigen-responsive. Given the close association between gastric MALT lymphoma and Helicobacter pylori, these organisms might be evoking the immunological response, and eradication of H pylori might inhibit the tumour. 6 patients in whom biopsies showed histological and molecular-genetic evidence of low-grade gastric B-cell MALT lymphoma with H pylori infection were treated with antibiotics. In all cases H pylori was eradicated and in 5, repeated biopsies showed no evidence of lymphoma. These results suggest that eradication of H pylori causes regression of low-grade B-cell gastric MALT lymphoma, and that anti-H-pylori treatment should be given for this lymphoma.

Adult↗