Biomedical subjects
N L Harris
Publications and source records attributed to N L Harris.
Thymoma classification. A siren's song of simplicity.
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Progressive transformation of germinal centers and nodular lymphocyte predominance Hodgkin's disease: a comparative immunohistochemical study.
To determine whether there might be immunophenotypic differences between nodular lymphocyte predominance Hodgkin's disease (NLPHD) and progressive transformation of germinal centers (PTGC) to aid in the differential diagnosis, we compared 16 cases of NLPHD with 13 cases of florid PTGC and 2 cases of focal PTGC. Paraffin-section immunohistochemistry was performed for CD20, CD45RA, CD45RO, CD3, CD43, CD57, EMA, CD30, and CD21. All PTGC cases showed well-circumscribed nodules of confluent sheets of CD20+ CD45RA+ small cells. T cells were scattered singly or in small groups. In 5 patients with florid PTGC, the T cells in some of the nodules formed rings around a few large transformed lymphocytes. In contrast, the nodules in all NLPHD cases showed an irregular, "broken-up" pattern with CD20 and CD45RA, and there were prominent T cell rosettes around the CD20+ large cells in all nodules. Rosettes of CD57+ cells and staining of large cells for EMA were seen in 3 and 2 cases of NLPHD, respectively, but not in PTGC. There were no differences between NLPHD and PTGC with respect to staining for CD30 or CD21. Three of the eight patients with florid PTGC and a few T cell rosettes had had persistent or recurrent lymphadenopathy; NLPHD developed in 1 of these patients 13 years later. We conclude that a combination of pan-B and pan-T antigens can be a useful adjunct to morphology in distinguishing NLPHD from PTGC. In approximately one-third of florid PTGC cases, T cell rosettes may be present, but they are notably fewer than those in NLPHD. Close follow-up of such patients may be appropriate.
Cutaneous lymphoid hyperplasia and cutaneous marginal zone lymphoma: comparison of morphologic and immunophenotypic features.
Cutaneous marginal zone lymphoma (MZL) is a recently described low-grade B-cell lymphoma that usually follows an indolent course. This tumor shares many histologic and clinical features with cutaneous lymphoid hyperplasia (CLH), a benign reactive lymphoid proliferation. Sixteen biopsy specimens from 14 patients with CLH were studied, and compared with 16 cases of cutaneous MZL (9 primary cutaneous, 7 with secondary involvement of the skin) to determine whether there were features that would permit their distinction on routinely fixed, paraffin-embedded tissue sections. Both disorders showed a female preponderance (CLH: 9 F, 5 M; MZL: 11 F, 5 M). The median age was also similar (CLH: 54 years; cutaneous MZL: 55 years). CLH was most common on the arm (8) and the head and neck (7) but also involved the trunk (1); primary cutaneous MZL most often involved the limbs (3), trunk (3), and head and neck (3). Lymphoma did not develop in any of the 14 CLH patients (follow-up ranging from 9 to 246 months, mean 62 months). Six of 9 patients with primary cutaneous MZL and all 7 patients with secondary cutaneous MZL experienced relapses, most commonly isolated to skin or a subcutaneous site. On hematoxylin-eosin stained sections, a diffuse proliferation of marginal zone cells (p < 0.0001), zones of plasma cells (p = 0.01), the absence of epidermal change (p = 0.01), reactive germinal centers (p = 0.03), and a diffuse pattern of dermal or subcutaneous infiltration (p = 0.03) were more often seen in cutaneous MZL. A dense lymphocytic infiltrate, bottom-heavy or top-heavy growth pattern, eosinophils, and a grenz zone were seen equally often in both disorders. Dutcher bodies were observed only in cutaneous MZL. Immunoperoxidase stains on formalin-fixed paraffin-embedded tissue sections showed monotypic expression of immunoglobulin light chains by plasma cells in 11 of 16 MZL cases. By definition, no case with monotypic plasma cells was diagnosed as CLH. In CLH, T cells usually outnumbered B cells, and a B:T cell ratio > or = 3:1 was not observed in any case. By contrast, 40% of the MZL cases showed a B:T cell ratio > or = 3:1. No coexpression of CD20 and CD43 was seen in any case of either MZL or CLH. In summary, the clinical presentations of CLH and MZL are similar. In contrast to historical criteria for diagnosing cutaneous lymphoid infiltrates, the presence of reactive follicles favors a diagnosis of cutaneous B-cell lymphoma (CBCL). In addition, a bottom-heavy or top-heavy growth pattern is not a distinctive finding. Marginal zone cells and zones or sheets of plasma cells are strong morphologic indicators of marginal zone lymphoma. The diagnosis of CBCL can be supported in 40% of the cases by demonstrating a B:T cell ratio of > or = 3:1, and confirmed in 70% of the cases by demonstrating monotypic light chain expression of plasma cells on paraffin sections.
Sinonasal lymphoma: a clinicopathologic analysis of 58 cases from the Massachusetts General Hospital.
Few large series compare lymphomas of the nasal cavity with those of the paranasal sinuses. We studied the cases of 58 patients, 34 males and 24 females, aged 7 to 92 years (mean, 57 years), who had lymphoma involving the nasal cavity or paranasal sinuses. Thirty-three patients had diffuse large B-cell lymphoma (DLBCL). Twenty-three were male and 10 were female, with an age range of 7 to 91 years (mean, 63 years); two were HIV-positive. Only 2 of 11 cases tested (one in an HIV-positive patient and one of lymphomatoid granulomatosis type) were Epstein-Barr virus (EBV)-positive. Thirty (91%) involved paranasal sinuses, 10 with nasal involvement, whereas three cases had nasal, but not sinus, involvement. At last follow-up, 16 (67%) were free of disease 7 to 169 months later (mean, 65 months), and 8 (33%) had died of disease 2 to 166 months later (mean, 45 months). Seventeen patients had nasal-type natural killer (NK)/T-cell lymphoma. There were 10 women and 7 men, aged 27 to 78 years (mean, 48 years). Thirteen of 14 were EBV-positive. Sixteen patients had nasal involvement, eight with sinus involvement. Eleven (73%) of 15 were alive and well 6 to 321 months later (mean, 139 months), three (20%) died of lymphoma 1, 11, and 12 months later, and one (7%) is alive with disease. There was one case each of marginal zone B-cell lymphoma, Burkitt's lymphoma, Burkitt-like lymphoma, peripheral T-cell lymphoma of unspecified type, and adult T-cell lymphoma/leukemia. In an additional three cases, the lymphomas were composed predominantly of large cells, but no immunophenotyping could be performed for subclassification. In 19 cases (17 DLBCLs, 1 Burkitt-like lymphoma, and 1 lymphoma of uncertain lineage), presenting symptoms included complaints related to the eyes. In 16 cases (13 DLBCLs, 1 Burkitt-like lymphoma, 1 nasal NK/T-cell lymphoma, and 1 lymphoma of uncertain lineage), the orbit was invaded by lymphoma. In our series, the most common lymphoma to arise in the sinonasal area is DLBCL, followed by nasal NK/T-cell lymphoma. Comparison of these two types of lymphoma showed that lymphomas involving sinuses without nasal involvement were predominantly DLBCLs (20 of 21), whereas nasal cavity lymphomas without sinus involvement were usually NK/T-cell type (8 of 11) (p = 0.000125). Compared with patients with DLBCL, patients with nasal NK/T-cell lymphoma were overall younger, with a lower male-to-female ratio. Lymphomas of B-cell lineage were more likely to be associated with symptoms related to the eyes (p < 0.0005) and to have extension to the orbit (p < 0.01) than were lymphomas of T- or NK-cell lineage. In contrast to results of Asian studies in which nasal NK/T-cell lymphoma has a very poor prognosis, our nasal NK/T-cell lymphomas had an outcome similar to that of DLBCL.
World Health Organization classification of neoplastic diseases of the hematopoietic and lymphoid tissues: report of the Clinical Advisory Committee meeting-Airlie House, Virginia, November 1997.
PURPOSE: The European Association of Hematopathologists and the Society for Hematopathology have developed a new World Health Organization (WHO) classification of hematologic malignancies, including lymphoid, myeloid, histiocytic, and mast cell neoplasms. DESIGN: Ten committees of pathologists developed lists and definitions of disease entities. A clinical advisory committee (CAC) of international hematologists and oncologists was formed to ensure that the classification would be useful to clinicians. The CAC met in November 1997 to discuss clinical issues related to the classification. RESULTS: The WHO uses the Revised European-American Lymphoma (REAL) classification, published in 1994 by the International Lymphoma Study Group, to categorize lymphoid neoplasms. The REAL classification is based on the principle that a classification is a list of "real" disease entities, which are defined by a combination of morphology, immunophenotype, genetic features, and clinical features. The relative importance of each of these features varies among diseases, and there is no one gold standard. The WHO Neoplasms recognizes distinct entities defined by a combination of morphology and cytogenetic abnormalities. At the CAC meeting, which was organized around a series of clinical questions, participants reached a consensus on most of the questions posed. They concluded that clinical groupings of lymphoid neoplasms were neither necessary nor desirable. Patient treatment is determined by the specific type of lymphoma, with the addition of grade within the tumor type, if applicable, and clinical prognostic factors, such as the International Prognostic Index. CONCLUSION: The WHO classification has produced a new and exciting degree of cooperation and communication between oncologists and pathologists from around the world, which should facilitate progress in the understanding and treatment of hematologic malignancies.
Report of an international workshop to standardize response criteria for non-Hodgkin's lymphomas. NCI Sponsored International Working Group.
Standardized guidelines for response assessment are needed to ensure comparability among clinical trials in non-Hodgkin's lymphomas (NHL). To achieve this, two meetings were convened among United States and international lymphoma experts representing medical hematology/oncology, radiology, radiation oncology, and pathology to review currently used response definitions and to develop a uniform set of criteria for assessing response in clinical trials. The criteria that were developed include anatomic definitions of response, with normal lymph node size after treatment of 1.5 cm in the longest transverse diameter by computer-assisted tomography scan. A designation of complete response/unconfirmed was adopted to include patients with a greater than 75% reduction in tumor size after therapy but with a residual mass, to include patients-especially those with large-cell NHL-who may not have residual disease. Single-photon emission computed tomography gallium scans are encouraged as a valuable adjunct to assessment of patients with large-cell NHL, but such scans require appropriate expertise. Flow cytometric, cytogenetic, and molecular studies are not currently included in response definitions. Response rates may be the most important objective in phase II trials where the activity of a new agent is important and may provide support for approval by regulatory agencies. However, the goals of most phase III trials are to identify therapies that will prolong the progression-free survival, if not the overall survival, of the treated patients. We hope that these guidelines will serve to improve communication among investigators and comparability among clinical trials until clinically relevant laboratory and imaging studies are identified and become more widely available.
Marginal zone B-cell lymphoma: A clinical comparison of nodal and mucosa-associated lymphoid tissue types. Non-Hodgkin's Lymphoma Classification Project.
PURPOSE: In the International Lymphoma Study Group classification of lymphoma, extranodal marginal zone B-cell lymphoma (MZL) of mucosa-associated lymphoid tissue (MALT) type is listed as a distinctive entity. However, nodal MZL is listed as a provisional entity because of questions as to whether it is truly a disease or just an advanced stage of MALT-type MZL. To resolve the issue of whether primary nodal MZL without involvement of mucosal sites exists and whether it is clinically different from extranodal MALT-type lymphoma, we compared the clinical features of these two lymphomas. PATIENTS AND METHODS: Five expert hematopathologists reached a consensus diagnosis of MZL in 93 patients. Seventy-three were classified as having MALT-type MZL because of involvement of a mucosal site at the time of diagnosis, and 20 were classified as having nodal MZL because of involvement of lymph nodes without involvement of a mucosal site. RESULTS: A comparison of the clinical features of nodal MZL and MALT-type MZL showed that more patients with nodal MZL presented with advanced-stage disease (71% v 34%; P =. 02), peripheral lymphadenopathy (100% v 8%; P <.001), and para-aortic lymphadenopathy (56% v 14%; P <.001) than those with MALT-type MZL. However, fewer patients with nodal MZL had a large mass (> or = 5 cm) than those with MALT-type MZL (31% v 68%; P =.03). The 5-year overall survival of patients with nodal MZL was lower than that for patients with MALT-type MZL (56% v 81%; P =.09), with a similar result for failure-free survival (28% v 65%; P =.01). Comparisons of patients with International Prognostic Index scores of 0 to 3 showed that those with nodal MZL had lower 5-year overall survival (52% v 88%; P =.025) and failure-free survival (30% v 75%; P =.007) rates than those with MALT-type MZL. CONCLUSION: Nodal MZL seems to be a distinctive disease entity rather than an advanced stage of MALT-type MZL because the clinical presentations and survival outcomes are different in these two types of MZL. Clinically, nodal MZL is similar to other low-grade, node-based B-cell lymphomas, such as follicular and small lymphocytic lymphomas.
Protocol for the examination of specimens from patients with non-Hodgkin's lymphoma: a basis for checklists. Cancer Committee, College of American Pathologists.
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Hodgkin's disease: classification and differential diagnosis.
During the past decade, there have been many advances in our understanding of Hodgkin's disease. Among the most important is the discovery that the Reed-Sternberg cell is a lymphoid cell, in most cases a B cell, and that it is clonal. Hodgkin's disease is thus a true lymphoma, deserving of a name change to Hodgkin's lymphoma (HL). On the basis of a combination of immunophenotype and morphologic features, the Revised European-American classification system recognizes two main types of HL: classical types (nodular sclerosis, mixed cellularity, lymphocyte-rich classical HL, and lymphocyte depletion) and nodular lymphocyte-predominant type. These two types probably are distinct biologic entities. The immunophenotype and genetic features of the classical HL and the nodular lymphocyte-predominant type have been defined. These are useful in the subclassification of HL and in distinguishing HL from two recently described, aggressive lymphomas that were in the past often diagnosed as HL, i.e., anaplastic large-cell lymphoma, T-cell type, and T-cell/histiocyte-rich large B-cell lymphoma. Epstein-Barr virus has been detected in approximately 40% of the cases of classical HL, and it is clonal; this suggests that this virus might play a role in the pathogenesis of at least some types of HL. Alternatively, its presence might simply reflect the prevalence of Epstein-Barr virus-infected B cells in the individual. Despite the advances of the past 10 years, many questions remain to be answered; these will provide the challenges of the next decade.
Lymphomas of the breast: pathology and clinical behavior.
Lymphocytes are present in normal breast. A lymphocytic mastopathy characterized by a lymphocytic infiltrate within the breast epithelium has been described, but its relevance as a precursor lesion of mucosa-associated lymphoid tissue (MALT)-type lymphoma of the breast is uncertain. Lymphomas of the breast are uncommon, and a broad variety of histologic types have been reported. The majority are B-cell lymphomas, and the most common type is diffuse large B-cell lymphoma (40% to 70%). MALT-type lymphoma is a distinct subgroup of primary lymphoma of the breast with a reported incidence between 0% and 44% and is characterized by indolent behavior and good prognosis. Burkitt's or Burkitt-like lymphoma can bilaterally involve the breast of a young pregnant or lactating woman and typically behaves aggressively. Primary breast lymphomas behave similarly to lymphomas of similar histologic types and stages presenting at other sites. Treatment of primary breast lymphomas does not include surgery, but is typically based on local radiotherapy, often combined with systemic chemotherapy.
Hodgkin's lymphomas: classification, diagnosis, and grading.
Much has been learned in the past decade from the study of tissues involved by the disorder long known as Hodgkin's disease. Two important discoveries have prompted changes in classification and nomenclature: first, the recognition that there are two distinct lymphomas encompassed within this category (classical and nodular lymphocyte-predominant [NLP] types), and second, the discovery that the Reed-Sternberg (RS) cells in most cases are monoclonal B cells. Thus "Hodgkin's disease" comprises two distinct lymphomas, deserving of a name change, to "Hodgkin's lymphomas" (HLs). The immunophenotype and genetic features of both classical HL and NLPHL have been defined. These are useful in the subclassification of HL and in distinguishing HL from two recently described, aggressive lymphomas that were in the past often diagnosed as HL: anaplastic large-cell lymphoma, T-cell type (ALCL), and T-cell/histiocyte-rich large B-cell lymphoma (T/HRBCL). Despite the advances of recent years, many questions remain to be answered, and these will provide the challenges of the next decade.
World Health Organization classification of neoplastic diseases of the hematopoietic and lymphoid tissues. A progress report.
The World Health Organization (WHO) classification has been developed under the joint auspices of the European Association for Hematopathology (EAHP) and the Society for Hematopathology (SH). First organized in 1995, the Steering Committee appointed 10 committees for T-cell and B-cell lymphomas and leukemias and myeloid and histiocytic tumors to develop a relevant list of diseases and establish definitions of each disease according to established criteria. The WHO classification uses the principles of the Revised European American Classification of Lymphoid Neoplasms (REAL), which defines each disease according to its morphologic features, immunophenotype, genetic features, postulated normal counterpart, and clinical features. The proposed classification was presented at the United States-Canadian Academy of Pathology meeting in 1997. The Steering Committee also appointed a Clinical Advisory Committee to ensure that the classification meets clinical needs and to resolve questions of clinical significance. The proposed WHO classification for lymphomas is similar to the REAL classification for lymphomas, with minor modifications and reassessment of provisional categories based on new data since 1994.
Lymphoid proliferations of the salivary glands.
Lymphoid proliferations of the salivary glands can be either reactive or neoplastic. Reactive lesions include cystic lymphoid hyperplasia--a multicystic ductal proliferation with reactive germinal centers, seen most often in intravenous drug users infected with HIV--and the lymphoepithelial sialadenitis of Sjögren's syndrome (so-called benign lymphoepithelial lesion [BLEL] or myoepithelial sialadenitis [MESA]). This lymphoid proliferation involves infiltration of ductal epithelium by lymphocytes of marginal zone or monocytoid B-cell type, forming lymphoepithelial lesions (epimyoepithelial islands). Patients with lymphoepithelial sialadenitis have a 44-fold increased risk of developing salivary gland or extrasalivary lymphoma, of which 80% are marginal zone/MALT type. Broad strands of marginal zone or monocytoid B cells around lymphoepithelial lesions and monotypic immunoglobulin detection by immunohistochemistry are considered diagnostic of MALT lymphoma. B-cell clones are detected in over 50% of cases of MESA by molecular genetic methods, but this does not correlate with overlymphoma. "Nodal" type B-cell lymphomas of the salivary glands are either follicular lymphoma (35%), which may arise in intrasalivary gland lymph nodes and behave similarly to follicular lymphoma in other sites, or diffuse large B-cell lymphoma (30%), which may arise de novo or secondary to either MALT or follicular lymphomas.
What are the criteria for distinguishing MALT from non-MALT lymphoma at extranodal sites?
Criteria for the diagnosis of low-grade B-cell lymphoma of mucosa-associated lymphoid tissue (MALT) type differed among participants in the Society for Hematopathology Workshop. Some would accept any extranodal lymphoma that lacked features of another lymphoma type as MALT type, while others required the presence of all morphologic criteria. Criteria for the diagnosis of MALT-type lymphoma can be clinical, morphologic, and biologic, and the implications of making the diagnosis may dictate how restrictive the criteria for diagnosis should be. The morphologic definition of MALT lymphoma is a lymphoma that recapitulates the structure of the Peyer's patch. The clinical definition is an indolent extranodal lymphoma that tends to remain localized or to recur in other extranodal sites, with a potential for cure with local therapy. The biologic definition is unknown, but it includes an antigen-stimulated B cell with a special relationship to epithelial tissues and germinal centers. For clinical purposes, exclusion of one of the other types of small B-cell lymphoma may be sufficient to dictate treatment. For investigation and further understanding of lymphomas, however, a more restrictive definition should be used, since there may be other small B-cell lymphomas not yet described.
Chronic pain and depression.
BACKGROUND: People presenting with chronic non-malignant pain provide the health practitioner with a therapeutic challenge. As medicine moves towards an emphasis on evidence based treatments, practitioners are reassessing approaches to chronic non-malignant pain. Depression is a common comorbidity that compounds the challenge, often going unrecognised. OBJECTIVE: To provide the reader with an insight into the current understanding of the comorbidity of chronic pain and depression, and an appreciation of the impact the two syndromes have upon each other. To assist the reader in understanding the biopsychosocial perspective, and to provide an introduction to various treatment approaches. DISCUSSION: It is a reality that general practitioners will carry the responsibility for the management of chronic pain sufferers as the multidisciplinary clinics continue to struggle with their unmanageable waiting lists. This article discusses the conceptual shift from the traditional medical model regarding the management of pain and pain related disorders.
SEK1/MKK4 is required for maintenance of a normal peripheral lymphoid compartment but not for lymphocyte development.
SAPK is a member of the group of evolutionary conserved stress-activated kinases that mediate control of cellular death and proliferation. In lymphocytes, the SAPK pathway has been implicated in signaling from antigen, costimulatory, and death receptors; SEK1, which directly activates SAPK, is required for early embryonic development and has also been reported to be essential for normal lymphocyte development. In contrast to the latter findings, we have used RAG-2-deficient blastocyst complementation to show that SEK1-deficient embryonic stem cells support unimpaired T and B lymphocyte development. Moreover, mature SEK1-deficient lymphocytes are capable of SAPK activation. Surprisingly, however, aging SEK1-deficient chimeric mice frequently develop lymphadenopathy and polyclonal B and T cell expansions. Thus, SEK1 is not required for lymphocyte development, but is required for maintaining peripheral lymphoid homeostasis.
Report of the European Task Force on Lymphomas: workshop on peripheral T-cell lymphomas.
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