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D H Wright

Publications and source records attributed to D H Wright.

At least 127 records · Page 7Linked to original sources
PubMed1985

Histogenesis of Burkitt's lymphoma: a B-cell tumour of mucosa-associated lymphoid tissue.

The designation Burkitt's lymphoma (BL) has proved to be of great convenience but has left undetermined the histogenesis of the tumour and its relationship to other B-cell lymphomas. One definition proposed for BL has been based on its relationship to Epstein-Barr virus (EBV). The EBV negativity of some BLs and the association of EBV with other non-Hodgkin's lymphoma, however, makes this definition unsatisfactory. Cytogenetic changes involving the translocations of part of chromosome 8 also are not specific for BL. In the Kiel classification, BL appears as a lymphoblastic lymphoma. However, lymphoblastic lymphomas and leukaemias arise from pre-B and early T cells, whereas BL shows characteristics of a more mature B cell. Mann et al. (1976) considered BL to be related to follicle centre-cell lymphomas. The morphology and immunological phenotype of BL are consistent with this hypothesis, although it would appear that BL is more restricted in its capabilities of further differentiation than other follicle centre-cell lymphomas. This lack of differentiation may be related to EBV infection. The characteristic anatomical distribution of BL is quite unlike that of most follicle centre-cell lymphomas and should be considered in the search for its histogenesis. BL involves the jaws during the period of maximum dental development, and also the salivary glands, thyroid, abdominal viscera and abdominal lymph nodes. Massive involvement of the breasts during pregnancy and lactation is characteristic.(ABSTRACT TRUNCATED AT 250 WORDS)

Africa↗
PubMed1984

Extranodal malignant lymphoma arising from mucosa-associated lymphoid tissue.

Four cases of extranodal malignant lymphoma, one each arising in the stomach, salivary gland, lung, and thyroid, are described. These cases have many clinical, histopathologic, and immunohistochemical features in common, and it is proposed that this is because they share a common pattern of histogenesis from mucosa-associated lymphoid tissue (MALT). Clinical features of MALT-derived lymphomas include a tendency to remain localized for prolonged periods, and, thus, to be responsive to locally directed therapy. Histologically, this group of tumors is characterized by a noninvasive lymphoplasmacytic infiltrate within which foci of follicle center cells (FCC) can be seen invading epithelial structures, forming lymphoplasmacytic infiltrate lesions. Immunohistochemistry reveals monotypic cytoplasmic immunoglobulin (CIg) in the plasma cells serving to highlight the CIg-negative lymphoepithelial lesions. The clinical and histopathologic features of these lymphomas can be understood in the context of the behavioral characteristics and morphology of MALT.

Adult↗
PubMed1984

Late recurrence in Hodgkin's disease: a report of two cases.

Two cases of Hodgkin's disease are described who relapsed 22 and 19 years after regional radiation therapy. One of the patients also developed a carcinoma of the large bowel soon after first relapse. The importance of long follow-up and documentation of cause of death in Hodgkin's disease is stressed.

Adult↗
PubMed1984

Sebaceous glands within the thymus: report of three cases.

Sebaceous glands in the thymus were discovered in three patients--two with myasthenia gravis and the other, who was operated on because of aortic valvular disease--with an unsuspected thymoma. Sebaceous glands not associated with hair follicles occur in diverse sites, the majority of which are in the head and neck or anogenital regions. Although most of these sites arise from the ectoderm, sebaceous glands have been reported in a thyroglossal duct, the larynx, and the esophagus, which are entodermal structures. Thus, precedents for ectodermally derived sebaceous glands in endodermal sites exist, but sebaceous glands have not previously been reported in the thymus. The authors speculate that their occurrence in the thymus may be related to the reported ectodermal contribution to the developing thymus by the epibranchial placode or cervical sinus.

Adult↗
PubMed1984

Primary malignant lymphoma of the lung: histopathologic and immunologic evaluation of nine cases.

Nine primary malignant lymphomas of the lung are described. Seven were localized lesions, and two were diffuse bilateral infiltrations. Histopathologic examination of these lesions suggests that they represent examples of the same entity and that it is a malignant lymphoma rather than a reactive infiltration or "pseudolymphoma." Histologic evidence of lymph node involvement is unusual, even in the presence of mediastinal or pleural infiltration. Immunohistochemical studies demonstrated a monotypic B-cell population in cases in which suitable tumor tissue was available for study (four of nine). Of the other five cases, two had a population of monotypic B lymphocytes in the peripheral blood, and in one of these and in one additional case gastric lymphomas subsequently developed. It is suggested that these lymphomas arise from bronchus-associated lymphoid tissue, which would explain both their histologic features and their tendency to remain localized to the lung for long periods.

Adult↗
PubMed1984

Immunoglobulin negative follicle centre cell lymphoma.

Immunoglobulin (Ig) could not be detected on the surface or in the cytoplasm of neoplastic cells from five cases of follicle centre cell lymphoma with centroblastic/centrocytic follicular histology when examined by immunohistology of frozen or wax embedded sections. Examination by fluorescein labelled antibodies of cells in suspensions prepared from the biopsies revealed a monotypic surface Ig positive population in one case and a surface or cytoplasmic Ig kappa:lambda light chain imbalance in a further two cases consistent with neoplastic B cell involvement: in all cases the proportion of cells failing to express Ig or T cell markers ranged from 24 to 75%. The monoclonal antibodies B1 (Pan B cell), FMC4 (HLA class II) and J5 (cALL antigen) stained the majority of cells in suspension with residual cells staining with UCHT1 or OKT11 (T cell monoclonal antibodies). In frozen sections, neoplastic follicular cells did not stain with UCHT1. However, in the one case tested these cells stained with the antibodies B1 and FMC4. In paraffin sections J chain could be demonstrated in the cytoplasm of three out of five cases. Cells from four cases were cultured in vitro for Ig production: two failed to produce Ig and monotypic light chains were the sole Ig product of the remaining two cases. The failure to express Ig by the majority of the neoplastic cells from the cases described in this report is at variance with the follicular histology of these neoplasms. Mechanisms responsible for this failure are discussed with reference to current models of B cell differentiation.

Antibodies, Monoclonal↗
PubMed1984

Spontaneous and Concanavalin A-induced suppressor activity in control and Hodgkin's disease patients.

Indirect evidence suggests that abnormal regulation of B cells exists in Hodgkin's disease (HD) due, perhaps, to the sequestration of regulatory T-lymphocyte subpopulations in the spleen in this condition. Other work implicates the B-cell itself in this abnormality. In this study we have attempted to measure regulatory T-cell function by quantitating spontaneous and Concanavalin A(Con A)-induced suppressor activity in T-enriched spleen cells from control and HD spleens for pokeweed mitogen(PWM)-induced immunoglobulin (Ig) production. Using this polyclonal system, HD patients' spleen T-lymphocytes could not be shown to differ markedly from the control series. Cells capable of spontaneous and mitogen-induced modulation of Ig synthesis were present in both populations and showed a reciprocal relationship implying the activation of the same cell type. In this respect HD and control spleen resembled peripheral blood. A limited parallel investigation of PWM-regulatory activity in cells from spleen and peripheral blood from individual patients was also undertaken. Individual patients showed wide variation in suppression between the two compartments and, therefore, measurements of functional capacity in blood alone may not provide a true estimate of total regulatory capacity in lymphoma patients.

B-Lymphocytes↗
PubMed1984

Primary gastric lymphoma--a tumour of mucosa-associated lymphoid tissue. A histological and immunohistochemical study of 36 cases.

A series of 36 cases of non-Hodgkin's lymphoma of the stomach have been analysed using routine histological techniques and immunohistochemistry. All cases were categorized as follicle centre cell lymphomas. Apart from two cases who had nodal lymphomas followed by gastric lymphomas, all cases appeared to represent primary lymphoma of mucosa-associated lymphoid tissue. It is proposed that the morphology and behaviour of these tumours reflect their origin from gut-associated lymphoid tissue. Physiologically well-differentiated examples show monotypic plasmacytic differentiation. Infiltration of gastric glands by follicle centre cells forming characteristic lympho-epithelial lesions is, we believe, a pathognomonic feature of primary gastric lymphoma. The spread of these tumours is within the mucosa-associated lymphoid tissues involving, in particular, the nasopharynx and lung but seldom spreading to peripheral lymph nodes or bone marrow. This concept of gastric lymphomas as primary neoplasms of gut-associated lymphoid tissue has important implications with respect to the investigation and treatment of this disease.

Adolescent↗
PubMed1984

Poor prognosis non-Hodgkin's lymphoma in the elderly: clinical presentation and management.

Thirty-eight patients age 65 years and older with a diagnosis of non-Hodgkin's lymphoma of poor prognostic type were seen over a five and a half year period. These patients represented 19 per cent of our total new patient non-Hodgkin's lymphoma population during this time. Advanced age, coexisting medical illness, widespread lymphoma and poor treatment compliance were common problems. Despite this we were able to render 26 per cent of patients disease-free for periods from 12 to over 48 months. Age should not be considered a bar to staging and effective therapy. Palliative management was unsuccessful, and we believe that treatment should be given with the intention of cure. Features suggesting that a patient was more likely to achieve a lasting complete remission included early stage (I-IIA), a lack of systemic ('B') symptoms, an absence of bone marrow or bulky gastrointestinal tract disease and no pre-existing serious medical condition.

Aged↗
PubMed1983

Malignant lymphoma of mucosa-associated lymphoid tissue. A distinctive type of B-cell lymphoma.

As illustrated in the two cases described in this paper close morphologic and immunohistochemical similarities exist between Mediterranean lymphoma (MTL) and primary gastrointestinal lymphoma of follicle center cell (FCC) origin as it occurs in Western countries. Similarities between the two conditions include a dense noninvasive monotypic lamina propria plasma cell infiltrate, present in all cases of MTL and in some cases of Western gastrointestinal FCC lymphoma, and an invasive infiltrate of FCCs morphologically distinct from the plasma cells. A distinctive lesion produced by individual gland invasion characterizes both types of lymphoma. A clonal relationship between the lamina propria plasma cells and the invasive FCCs, long suspected but never proved in MTL, can be demonstrated in Western cases. Many of the histologic and clinical features common to these lymphomas can be explained in the context of the normal maturation sequences of gut associated lymphoid tissue. It is suggested that MTL and Western cases of primary FCC gastrointestinal lymphoma share a common histogenesis from mucosa associated lymphoid tissue.

Adult↗
PubMed1983

Malignant lymphoma of true histiocytic (monocyte/macrophage) origin.

Since the advent of the newer classifications of non-Hodgkin's lymphoma and the realization that the majority of tumors classified as histiocytic under the Rappaport classification were in fact of lymphocytic origin, there have been remarkably few reports of true histiocytic (monocyte/macrophage) tumors and it has been suggested by some that such tumors should not be considered as a variety of malignant lymphoma. This article describes five patients with malignant lymphoma of neither B- or T-lymphocyte origin in whom the malignant cells could be characterised immunologically, cytochemically, and immunohistochemically as of true histiocytic derivation. The cases showed considerable morphologic diversity but there were shared characteristics at both light microscopic and ultrastructural levels. Positive immunohistochemical staining for alpha 1-antitrypsin was the single most useful criterion in classifying these tumors. Without the use of special techniques there were no clinical or pathologic features that reliably distinguished these cases from non-Hodgkin's lymphomas of lymphocytic derivation. Tumors of histiocytic origin are, therefore, inevitably being included among the non-Hodgkin's lymphomas and are most appropriately classified as such. Identification of histiocytic lymphomas should be encouraged so prognosis and optimum treatment can be established.

Acid Phosphatase↗
PubMed1983

Epstein-Barr virus markers in a series of Burkitt's lymphomas from the West Nile District, Uganda.

In an epidemiological survey in the West Nile District of Uganda, 70 pathologically confirmed BL cases were detected over a 5-yr period; this corresponded to an annual incidence rate of 1.6 per 100,000 general population or about 5 per 100,000 children in the age group 5-14 yr. Of the confirmed cases which were examined by EBV/DNA molecular hybridization, 96% were found to contain an average of 38 EBV genome equivalents per tumour cell, whereas none of the examined unconfirmed cases did. Duplicate hybridization assays in two laboratories were in close agreement. Serological testing showed that 91% of the confirmed BL cases had elevated EBV/VCA titres (greater than or equal to 160) and 64% were EA(D)-positive (greater than or equal to 10). Most of the cases with high EBV/genome content had high VCA titres, but there was a poor correlation between the two parameters among all cases. This study confirms that in high BL incidence areas the association between EBV and this lymphoma is almost constant, whereas it is exceptional in low-incidence areas. This further supports the aetiological implication of EBV in the endemicity of this tumor in equatorial Africa.

Adolescent↗
PubMed1983

Radiation under phototherapy and its relationship to clinical effectiveness in moderately severe neonatal jaundice.

Radiation under four commercially available phototherapy units was measured over the visual spectrum and demonstrated that between 69 and 87 per cent of the radiation was irrelevant to the photodegradation of bilirubin. When infants with moderately severe physiological jaundice were exposed to three of the same phototherapy units under the same conditions there was no demonstrable difference in the apparent rate of decline of serum bilirubin or in length of treatment required.

Dose-Response Relationship, Radiation↗
PubMed1982

Correlation between Ig-synthesis patterns and lymphoma classification.

This study examines the link between free immunoglobulin (Ig) light-chain (LC) secretion and the developmental stage of the neoplastic B-cell of origin in B-cell lymphomas. The Kiel developmental scheme for lymphoma classification has been used to define the tumour-cell populations. Twenty-four B-cell lymphomas have been studied. In the small-lymphocytic lymphoma group, secreted Ig consisted of LC exclusively or in excess over heavy-chain (HC). Lymphomas of follicular-centre-cell origin, considered to be from cells further along the normal B-cell differentiation pathway, can be divided into centroblasts or centrocytes according to their histological appearance in tissue sections. Centroblastic lymphomas exhibited strong surface IgM or IgG expression, and the secretion of whole Ig was higher than by cells from the small-lymphocytic lymphomas. Synthesis of HC and LC was balanced in these cultures, both intracellularly and in secreted material. The centrocytic lymphomas comprised a functionally more heterogeneous group, the SIg varied in intensity and was of surface IgM, D or G. Likewise Ig synthesis was variable in quantity and composition, some cases secreting LC exclusively while others, including the cases expressing SIgG, secreted balanced HC and LC. In the Kiel classification centrocytes are considered to be more mature than centroblasts. Our data suggest that centrocytic lymphomas are heterogeneous in origin, some preceding and others following centroblasts in the B-cell maturation sequence. These data are discussed in relation to current concepts of B-cell maturation and lymphoma histology.

B-Lymphocytes↗
PubMed1982

Macrophage origin of Reed-Sternberg cells: an immunohistochemical study.

In an immunohistochemical study of 26 biopsies from 24 patients with Hodgkin's disease a granular staining pattern for alpha-1-antitrypsin (alpha(1)AT) and alpha-1-antichymotrypsin (alpha(1)ACT) was seen in Reed-Sternberg (RS) cells and mononuclear Hodgkin's (H) cells in over half the cases. The pattern of staining for these antiproteases seen in RS and H cells has previously only been observed in normal and malignant cells of the monocyte/macrophage lineage within the lymphoreticular system. A faintly granular evenly distributed staining for IgG was found in viable RS and H cells. This staining was associated with a similar distribution of both light chains but not J chain, suggesting that the immunoglobulin had not been synthesised by these cells but had been taken up from the extracellular environment. It is suggested that this uptake is an active process occurring in viable RS and H cells, possibly via Fcgamma receptors and further supports an origin from cells of the monocyte/macrophage lineage. IgA, IgD, albumin, fibrinogen, C1q, C4 and C3 were present in some cells, IgM was more rarely found and lysozyme was absent. The fact that cells staining for these serum proteins generally showed signs of degeneration and that the extent of staining correlated with the molecular weight, but not serum concentration, of the protein suggests that they are passively acquired by dead or dying cells and thus represent a separate phenomenon from IgG uptake. The function of IgG uptake and accumulation by RS cells and the alpha(1)AT and alpha(1)ACT markers may prove of use in identifying the macrophage subtype from which these cells are derived.

Blood Proteins↗