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L M Weiss

Publications and source records attributed to L M Weiss.

At least 361 records · Page 20Linked to original sources
PubMed1985

Morphologic and immunologic characterization of 50 peripheral T-cell lymphomas.

Fifty T-cell lymphomas, excluding mycosis fungoides and lymphoblastic lymphoma, were studied morphologically and immunohistochemically with a panel of monoclonal antibodies reactive with T-cell differentiation antigens in fresh frozen tissue. Histologically, 36% of the lymphomas were large-cell immunoblastic, 26% were diffuse large-cell, 22% were diffuse mixed small and large-cell, and 16% were monomorphic medium-sized-cell lymphomas. By immunologic studies, 64% of the lymphomas were of helper phenotype, 12% were of cytotoxic/suppressor phenotype, 8% expressed both helper and cytotoxic/suppressor suppressor antigenic markers, and 16% lacked detectable markers for either helper or cytotoxic/suppressor cells. There was no correlation between histologic category and immunophenotype. A common finding, and one which may prove to be helpful in the diagnosis of T-cell lymphomas, was the loss of one or more of the pan-T antigens Leu 1, 4, and 5 or the T-cell antigen Leu 9 in 32 cases. The expression of Leu 1 and Leu 9 was lost in 46% of cases, expression of Leu 4 was lost in 26%, and expression of Leu 5 was lost in 24%. About three-quarters of the lymphomas expressed Ia antigens.

Antibodies, Monoclonal↗
PubMed1985

Immunophenotypic differences between dermatopathic lymphadenopathy and lymph node involvement in mycosis fungoides.

The authors applied a battery of monoclonal antibodies to T cells and other hematolymphoid cells on frozen tissue sections of lymph nodes with involvement by MF and DL, both with and without a history of MF. All 13 lymph nodes showing histologic involvement with MF showed immunophenotypic abnormalities. All of these cases showed significant loss of Leu-9 expression, and 10 cases showed significant loss of Leu-8 expression. In addition, occasional cases showed loss of the pan-T-cell markers Leu-1, 4, and 5. All cases of DL of histologic grade LN-0 or 1, with or without a history of MF, showed a predominance of T helper cells in paracortical regions without evidence of immunophenotypic abnormalities. Three of the 4 cases of DL of histologic grade LN-2 or 3 showed significant loss of Leu-8 and/or Leu-9 expression identified by a decrease in the ratio of paracortical Leu-8/Leu-4 or Leu-9/Leu-4-expressing cells, all cases with a history of possible or definite MF. These results raise the possibility that the immunologic methods employed may be able to identify cases of DL with early involvement by MF.

Antibodies, Monoclonal↗
PubMed1985

Non-Hodgkin's lymphomas of the lung. A study of 19 cases emphasizing the utility of frozen section immunologic studies in differential diagnosis.

Nineteen cases of possible non-Hodgkin's lymphoma of the lung were studied by conventional morphologic methods and by immunohistochemical methods employing monoclonal antibodies applied to frozen tissue sections. In five of the 19 cases, the original histologic diagnoses were revised after review of the immunologic findings. Problem areas clarified by immunodiagnosis included the differential diagnoses of pseudolymphoma versus small lymphocytic lymphoma (two cases), Hodgkin's disease versus non-Hodgkin's lymphoma (two cases) and non-Hodgkin's lymphoma versus lymphomatoid granulomatosis (one case). Of the seven lymphomas presenting exclusively in the lung without a prior history of lymphoma, three were small lymphocytic, one was diffuse mixed small cleaved and large cell, and three were diffuse large-cell lymphomas. Four of these lymphomas typed as B-cell, two typed as T-cell, and one was of undefined phenotype.

Adolescent↗
PubMed1985

Practical approach to the immunodiagnosis of lymphomas emphasizing differential diagnosis.

Immunological studies on tissue sections are often useful for supporting a diagnosis of lymphoma in cases with unusual histological or clinical findings and for identifying clinically important subgroups of lymphoma. Recent advances in both reagents and immunohistochemical methods allow the construction of monoclonal antibody panels for use both on routinely-fixed and processed tissues and on fresh frozen tissues. Commercially available monoclonal antibodies that are reactive with fixation-resistant antigenic determinants on lymphoid and related differentiation antigens often allow the distinction of lymphoma from non-lymphoid neoplasms. Better reagents and/or methods are needed for the identification of subset and lineage-specific markers on B cells and T cells and on the atypical cells of Hodgkin's disease. The use of fresh frozen tissue allows the application of a wide range of monoclonal antibodies to B-cell, T-cell and accessory cell differentiation antigens, many of which react only in fresh tissue. Appropriate monoclonal antibody panels distinguish B-cell lymphoma and Ig- B lineage lymphoma from hyperplasia. A broad panel of antibodies to T-cell differentiation antigens is needed to identify the abnormal T-cell phenotypes which are observed in T-cell lymphoma.

Antibodies, Monoclonal↗
PubMed1985

Pancreatitis after cardiac and cardiopulmonary transplantation.

In a review of 176 patients who died after either cardiac or cardiopulmonary transplantation, 15 cases of pancreatitis were identified. The diagnosis was clinically inapparent in 11 of the 15 cases of pancreatitis. A high index of suspicion should therefore be maintained when these patients are cared for. A variety of factors may have contributed to the occurrence of pancreatitis in these patients. These include infection, steroids, azathioprine, low-flow states, extracorporeal circulation, vasopressors, renal failure, and rejection.

Adolescent↗
PubMed1985

Frequent immunoglobulin and T-cell receptor gene rearrangements in "histiocytic" neoplasms.

The authors have analyzed the DNA of immunoglobulin and T-cell receptor genes in a series of 6 malignancies which were judged to be of histiocytic derivation on the basis of morphologic criteria. They found that 4 of these cases showed rearrangements of the beta T-cell receptor genes in spite of the lack of any specific immunohistochemical markers for B or T cells. One case showed rearrangements of both heavy and light chain immunoglobulin genes and probably represents either a sinusoidal large cell lymphoma or a B-cell lymphoma with activation of histiocytes simulating malignant histiocytosis. A single case lacked both immunoglobulin and T-cell receptor rearrangements consistent with immunologic analyses that suggested its origin from an interdigitating reticulum cell. The result of this study in conjunction with the authors' previous immunologic observations suggests that many presumed histiocytic malignancies actually represent T-cell lymphomas. Alternatively, beta T-cell receptor rearrangement may be a common feature of tumors that show monocyte/histiocytic differentiation.

Antibodies, Monoclonal↗
PubMed1985

Gastrointestinal lymphomas. Immunohistochemical studies on the cell of origin.

The classification of primary malignant lymphomas of the gastrointestinal tract by their cell of origin has been a subject of great controversy in recent years, with the proportion of histologic subtypes varying substantially in different published series. Much of this controversy was initially due to the widely recognized inherent difficulty of classifying lymphomas based on routine histologic sections alone. However, the advent of immunohistochemical techniques has also yielded disparate results. Particularly contentious has been the notion of true histiocytic lymphomas, which some investigators have claimed to be relatively frequent in the gastrointestinal tract, whereas others doubt whether they exist at all. We present here a classification of 25 gastrointestinal lymphomas seen in the surgical pathology services of UCLA Hospital and Stanford University Medical Center. Unlike all previously reported series, we have utilized frozen tissue sections for the performance of immunohistochemical studies, which we and others have found to be far more reliable than the use of formalin-fixed, paraffin-embedded tissues, particularly in detecting monoclonal surface staining of immunoglobulin light- and heavy-chain markers. We find that this technique lessens the likelihood of overinterpreting the stains for histiocyte markers (alpha 1-antitrypsin and lysozyme), which are often difficult to read owing to strong positive staining of benign reactive histiocytes within the tumor. Utilizing these techniques, we have been able to classify definitely 21 of our 25 lymphomas (84%) as of B-cell origin, whereas none appeared to be histiocytic. We conclude that true histiocytic lymphomas of the gastrointestinal tract must be very rare, and we recommend the routine use of frozen tissue sections for more accurate classification of these interesting lesions.

Adult↗
PubMed1985

Most null large cell lymphomas are B lineage neoplasms.

DNA of immunoglobulin and the beta T cell receptor genes was analyzed for rearrangements in 34 diffuse large cell lymphomas that failed to express immunoglobulins or T cell antigens. Twenty-eight cases had both heavy and light chain immunoglobulin rearrangements, two cases had only heavy chain gene rearrangements, three cases had only light chain gene rearrangements, and one case failed to show rearrangements for any of the immunoglobulin genes. None of the cases showed rearrangements for the beta T cell receptor gene. These results indicate that the vast majority of diffuse large cell lymphomas that lack definitive B or T cell phenotypic markers are actually B cell in origin.

Antigens, Differentiation, B-Lymphocyte↗
PubMed1985

T-cell signet-ring cell lymphoma. A histologic, ultrastructural, and immunohistochemical study of two cases.

The histologic, ultrastructural, and immunologic characteristics of two signet-ring cell lymphomas of T-cell derivation are presented. Histologically, both lymphomas were diffuse large cell lymphomas with many neoplastic cells containing cytoplasmic vacuoles imparting a signet-ring configuration. Ultrastructural examination revealed the vacuoles to consist of electron-lucent spaces containing variable numbers of microspherules. Immunohistochemical studies showed that both lymphomas expressed T-cell phenotypes with no reactivity with antibodies to B-cell antigens. In contrast to previous reports which have shown signet-ring cell lymphomas to be invariably B-cell in derivation and usually follicular center cell type, this study demonstrates that these lymphomas may also be of T-cell origin.

Head and Neck Neoplasms↗
PubMed1984

Ultrastructural distinctions between adult pleomorphic rhabdomyosarcomas, pleomorphic liposarcomas, and pleomorphic malignant fibrous histiocytomas.

The ultrastructural features of five pleomorphic rhabdomyosarcomas, five high-grade malignant fibrous histiocytomas, and five pleomorphic liposarcomas were studied. Electron microscopy was found to be consistently useful in distinguishing between these tumors. The rhabdomyosarcomas showed thick and thin filaments in complexes and consistently contained glycogen. The malignant fibrous histiocytomas had numerous lysosomes, often in cells with ruffled borders, and contained cells showing "myofibroblastic" differentiation. The liposarcomas showed abundant and coalescing lipid droplets, sparse stroma with condensation of amorphous granular materials surrounding plasma membranes, and prominent vascularity. Fourteen of the 15 tumors could be identified on the basis of ultrastructure; thus, electron microscopic examination is an important diagnostic tool for pleomorphic tumors.

Cytoskeleton↗
PubMed1984

Keratin proteins and carcinoembryonic antigen in synovial sarcomas: an immunohistochemical study of 24 cases.

Twenty-four synovial sarcomas were examined for the presence of keratin proteins by an indirect immunoperoxidase method with paraffin-embedded tissues. Keratin proteins were identified in 16 of 24 cases (67 per cent). Both the pseudoglandular and spindle cell areas of all eight of the biphasic synovial sarcomas and the spindle cells of eight of the 16 monophasic synovial sarcomas contained keratin proteins. In spindle cell areas, staining was observed in single cells and small cords and clusters of cells in the absence of cleft formation or other evidence of a pseudoglandular component. The predominant cytologic staining pattern in all cases was peripheral, with localization of staining to the cell membrane or adjacent areas, but diffuse and focal cytoplasmic staining patterns were also observed. No staining for keratin proteins was seen in 101 control cases, including 52 sarcomas of various types. Carcinoembryonic antigen was also identified in four of the 24 synovial sarcomas by an indirect immunoperoxidase technique. The identification of keratin proteins may be helpful in the pathologic diagnosis of synovial sarcoma, particularly the spindle cell monophasic variant.

Adult↗
PubMed1984

Comparative histologic study of 43 metastasizing and nonmetastasizing adrenocortical tumors.

A series of 43 adrenocortical tumors was analyzed using nine histologic features. Mitotic activity, especially with atypical forms, and venous invasion correlated best with metastasizing or recurring tumors; however, no single criterion was useful alone. The combination of the following nine criteria was most useful in distinguishing malignant from benign tumors: nuclear grade III or IV; mitotic rate greater than 5/50 high-power fields; atypical mitoses; clear cells comprising 25% or less of the tumor; a diffuse architecture; microscopic necrosis; and invasion of venous, sinusoidal, and capsular structures. None of the 24 tumors with two or less of these criteria metastasized or recurred, while all but one of the 19 tumors with four or more of these criteria either recurred or metastasized.

Adenoma↗
PubMed1984

Adenolymphoma with massive necrosis and squamous metaplasia.

A 61-year-old female presented with a longstanding parotid mass with recent change in size. Histologically, the mass was composed of extensively necrotic tissue with a peripheral rim of ribbons of epithelium. In one focus, a double layer of oxyphilic epithelium overlying a lymphoid stroma in a papillary configuration was present, establishing the diagnosis of adenolymphoma (AL). The possibility of infarction and/or infection complicating AL is discussed. In any parotid gland lesion clinically presenting as a longstanding tumor with recent change clinically suggestive of infarction and/or infection, the diagnosis of AL should be considered. In the pathologic specimen with extensive necrosis, areas of preserved epithelium and stroma should be searched for carefully to confirm the diagnosis.

Adenolymphoma↗
PubMed1983

Disseminated Aspergillus ustus infection following cardiac surgery.

Aspergillus ustus is a soil residing fungus that rarely has been implicated in human infections. A 72-year-old man who had undergone surgery for mitral valve replacement and triple coronary artery bypass developed progressive pneumonia with A. ustus. The infection had spread to other organs and finally was diagnosed at postmortem examination.

Aged↗
PubMed1983

Medullary carcinoma arising in a thyroid with Hashimoto's disease.

A 51-year-old woman presented with a large goiter and on pathologic examination was found to have both Hashimoto's thyroiditis and medullary carcinoma of the thyroid. To our knowledge, this is the first well-documented case of the coexistence of these two entities in the same patient in the English literature. The association of Hashimoto's disease and carcinoma of the thyroid is reviewed and its relevance discussed.

Amyloid↗