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M Pea

Publications and source records attributed to M Pea.

14 recordsLinked to original sources
PubMed1992

Diagnostic and therapeutic problems in multicentric renal angiomyolipoma.

Multicentric renal angiomyolipoma is a rare form of benign tumor. However, its effective incidence as evaluated in autopsy studies may be as high as 8%. There are 2 main types of renal angiomyolipoma, that is isolated forms and those associated with other diseases, such as phakomatosis, polycystic kidneys and fibromuscular dysplasia. The tumor may also display malignant behavior with local invasiveness and regional lymph node involvement. However, the clinical course is benign and multicentricity is important for prognosis. Histopathological diagnosis often is difficult. Immunohistochemical analysis of surgical specimens using a panel of monoclonal antibodies, including HMB-45 and actin, enabled us to make a definitive diagnosis in 3 cases of multicentric renal angiomyolipoma.

Adolescent↗
PubMed1992

PEC and sugar.

Explore the source record for details and available documents.

Hemangioma↗
PubMed1991

False-positive immunostaining of normal epithelia and carcinomas with ascites fluid preparations of antimelanoma monoclonal antibody HMB45.

HMB45 is a melanoma-specific monoclonal antibody that has found widespread use in diagnostic pathology. Recent reports, however, have suggested that this antibody may cross-react with a small number of carcinomas and other epithelial cells. The authors tested the hypothesis that these latter reports represent examples of false-positive immunostaining by comparing the immunostaining on breast, salivary gland, and lung tumors with the following: (1) a commercial ascites preparation of this monoclonal antibody; (2) a protein A-purified antibody preparation derived from ascites fluid; and (3) supernatant fluid obtained from the hybridoma cell line. The authors found that all examples of nonmelanoma immunostaining in the carcinomas tested were eliminated with the nonascites fluid preparations, whereas strong immunostaining of melanomas was retained. The authors conclude that contaminated commercial ascites fluid preparations of HMB45 may account for most, if not all, of the reports of nonmelanoma immunostaining with HMB45.

Antibodies, Monoclonal↗
PubMed1991

Melanocyte-marker-HMB-45 is regularly expressed in angiomyolipoma of the kidney.

HMB-45 (melanocytic cell-specific monoclonal antibody) immunoreactivity was investigated in 10 cases of angiomyolipoma (AML) (1 with massive regional lymph node involvement) of the kidney and detected in all of them. No HMB-45 immunoreactivity was found in other tumors of the region which can occasionally be confused with AML, such as renal cell carcinoma, Wilms' tumor, and retroperitoneal sarcoma (leiomyosarcoma and liposarcoma). These findings indicate that HMB-45 is not a melanocyte-restricted marker and suggest that its expression might be useful in distinguishing AML from other tumors of the kidney and retroperitoneum.

Antibodies, Monoclonal↗
PubMed1990

Peripheral giant cell granuloma: evidence for osteoclastic differentiation.

Nine cases of peripheral giant cell granuloma of the oral cavity have been immunohistochemically analyzed to assess the nature of the giant cells. Giant cells were unreactive when tested with antibodies recognizing myelomonocytic and macrophage markers (lysozyme, MAC 387, HAM 56) but showed strong immunoreactivity with MB1, an antibody reactive with osteoclasts. It is concluded that giant cells characterizing giant cell granuloma exhibit a phenotype distinct from other giant cells found in sites of chronic inflammation and may be true osteoclasts.

Antibodies, Monoclonal↗
PubMed1990

Small-cell neuroendocrine carcinoma of the ampullary region. A clinicopathologic, immunohistochemical, and ultrastructural study of three cases.

We report the clinicopathologic, immunohistochemical, and ultrastructural features of three small-cell neuroendocrine carcinomas of the ampullary region of the duodenum. All patients were men; their ages were 51, 62, and 66 years. The therapy consisted of pancreatoduodenectomy. All patients died of the disease; median survival was 10 months from the diagnosis. The histological appearance was identical to pulmonary and extrapulmonary small-cell carcinoma. The neuroendocrine differentiation was demonstrated ultrastructurally by the presence of dense-core granules, and by the positive immunoreaction for neuron-specific enolase and Leu-7 in each case. One case expressed a focal positivity for chromogranin A (PHE-5) and argyrophilic granules. The same case showed the presence of neurofilaments on frozen material. Neurofilament proteins could not be demonstrated in any case in paraffin sections. Neoplastic cells exhibited cytoplasmic immunostaining for cytokeratins (CAM 5.2) in all cases. In one case, a large number of neoplastic cells (60-70%) exhibited nuclear Ki-67 positivity. We postulate that the disease's histogenesis was from epithelial stem cell expressing both epithelial and neuroendocrine characteristics. The clinical behavior of small-cell neuroendocrine carcinomas of the ampullary region appears to be extremely aggressive, with early metastases and fatal outcome.

Adenocarcinoma↗
PubMed1989

Immunocytochemical detection of progesterone receptor by monoclonal KD-68 antibody in operable breast cancer: correlations with biochemical assay, pathological features and cell proliferative rate.

A new immunocytochemical assay (ICA) for progesterone receptor (PgR), employing the rat monoclonal KD-68 antibody and a sensitive peroxidase-anti-peroxidase (PAP) technique as the displaying system, was performed in 129 human breast cancer specimens. PgR-ICA staining was almost all electively located in neoplastic cell nuclei with a substantial heterogeneity in distribution and intensity. To study the basic relationship of the results of the ICA method with the biochemical dextran-coated charcoal (DCC) assay we compared, in all the same specimens, the antibody nuclear staining with the PgR positivity by DCC (cut-off value of 10 fmol/mg of protein). We found an overall agreement of 77% between the two methods and a PgR-ICA sensitivity of 83% and a specificity of 72%, assuming that biochemical PgR is truth. PgR-ICA false-negative results were only nine out of 53 (17%); and false-positive were 21 out of 76 (28%). Using both methods no significant association was observed between PgR positivity with menopausal status, histological type, tumor size and lymph node status. The correlations between PgR expression and cell kinetics were assessed by an immunocytochemical method employing the monoclonal Ki-67 antibody. While a significant negative relationship was found between high Ki-67 score and PgR-ICA positivity (P less than 0.01) no correlation was found with DCC positivity. The present results demonstrate that ICA is a practical, reliable and inexpensive method with a good correlation to the conventional biochemical assay to determine the PgR status. Moreover, ICA recognizes PgR expression at the single cell level, thus providing additional information to the quantitative DCC assay that should improve the prognostic evaluation and the prediction of responsiveness to endocrine therapy in breast cancer.

Adult↗