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H K Park

Publications and source records attributed to H K Park.

At least 19 recordsLinked to original sources
PubMed1995

Significance of epithelial membrane antigen in the work-up of problematic serous effusions.

Differentiation of reactive and/or atypical mesothelial cells from malignant epithelial cells in serous effusions remains a frequent diagnostic problem. Since epithelial membrane antigen (EMA) positive malignant cells in serous effusions have been reported in almost all adenocarcinomas and most malignant mesotheliomas, immunoreactivity for EMA is felt to be less useful than other antibodies in the workup of problematic serous effusions. However, immunostaining of reactive and/or atypical benign mesothelial cells for EMA has not been well studied, with only a few series reporting either weak or negative staining for EMA. This study was undertaken to evaluate how often reactive and/or atypical appearing mesothelial cells stain positively for EMA. One hundred eighty serous effusions (115 pleural, 55 peritoneal, and 10 pericardial) from 123 females and 57 males ages 20 to 89 yr were evaluated in which an antibody panel including EMA was performed on cell blocks (141 cases), cytospins (36 cases), or both (3 cases). Of the 100 cytologically positive cases, EMA immunoreactivity was present in 97/100 (97%) cases. One EMA negative case suspicious for a metastatic renal cell carcinoma was lost to follow-up and not included in the analysis. The remaining three negative cases consisted of malignancies not expected to have EMA positive cells (small cell carcinoma, neuroblastoma, and synovial sarcoma). Therefore, EMA was positive in virtually 100% of the remaining malignant cases. In the 78 cytologically negative cases, EMA positivity was present in 3/78 (3.8%) cases. Clinical follow-up of up to 14 mo in these three cases revealed no evidence of malignancy.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Nucleotide sequence of the pectate lyase gene from alkali-tolerant Bacillus sp. YA-14.

The nucleotide sequence of the pectate lyase gene (pe lK) from alkali-tolerant Bacillus sp. was identified and analyzed. A 1,260-base pair open reading frame for the pe lK gene was observed and encoded for a protein of 420 amino acids. The signal peptide was composed of 21 amino acid residues. In the deduced primary structure of this enzyme, the three conserved regions of several pectate lyases were found and showed high homologies.

Alkalies↗
PubMed1992

Prenatal diagnosis of Pompe's disease (type II glycogenosis) in chorionic villus biopsy using maltose as a substrate.

Uncultured trophoblasts obtained from chorionic villus biopsy during the gestation period of 8-12 weeks were assayed for alpha-glucosidase activity using maltose as the substrate. Only one major form of maltase activity with a pH optimum at 4.0 was demonstrated. Using this method, we performed prenatal diagnosis on three pregnancies at risk for the infantile form of type II glycogen storage disease. Two affected fetuses and one unaffected fetus were predicted and the diagnosis was subsequently confirmed. The maltose assay offered a direct, simple, and sensitive method for prenatal diagnosis of Pompe's disease in the first trimester.

Chorionic Villi Sampling↗
PubMed1992

Nonviable autologous bronchoalveolar lavage cell preparations induce intradermal epithelioid cell granulomas in sarcoidosis patients.

Intracutaneous injection of sarcoidosis patients with Kveim-Siltzbach antigen (KSAg), a particulate suspension of granulomatous sarcoidal spleen, induces an influx of T-helper lymphocytes and monocyte-macrophages followed by epithelioid cell granuloma formation. In the lung, similar granulomas form from an alveolitis of similar mononuclear cells, which may harbor a Kveim-like granulomagenic factor. To assess this possibility, preparations of nonviable autologous bronchoalveolar lavage cells (NABC) and KSAg were injected intracutaneously at different sites and biopsied at 4 to 5 wk. Of 22 sarcoidosis patients, nine (41%) developed typical granulomas at the NABC site, while all developed granulomas at the KSAg site. Responders to NABC had more recent onset of symptoms than nonresponders (3.2 versus 23.7 months, p less than 0.01), but did not have significantly higher percentages of lavage lymphocytes or more rosetting of lymphocytes about alveolar macrophages. None of 11 normal volunteers developed granulomas in response to NABC. Epithelioid cell granulomas at NABC and KSAg sites were similar by hematoxylin-eosin staining and by biotin-avidin-peroxidase immunohistochemical staining with monoclonal antibodies Leu-1, Leu-14, Leu-2a, Leu-3a, anti-interleukin-2 receptor, and polyclonal antibodies against lysozyme and alpha 1-anti-chymotrypsin. Symptomatic onset of sarcoidosis is associated with an autologous lavage cell factor that induces intradermal epithelioid cell granulomas that are immunophenotypically similar to Kveim-induced granulomas.

Adult↗
PubMed1992

CEA immunoreactivity in metastatic malignant melanoma.

Immunohistochemical techniques may aid in the diagnosis of poorly differentiated metastatic tumors. Anti-carcinoembryonic antigen (CEA) antibodies have been used in the identification of epithelial neoplasms. However, recent unpublished data report CEA reactivity in malignant melanoma and melanoma cell lines. We studied 28 cases of known metastatic malignant melanoma with an antibody panel for CEA (polyclonal and monoclonal), AE1:3, S-100, and HMB-45. Reactivity for CEA (polyclonal) was seen in 15 of 28 (53%) cases: nine exhibited strong diffuse positivity, five moderate focal positivity, and one globular cytoplasmic staining. Focal reactivity for cytokeratin (AE1:3) was seen in three of 28 cases. HMB-45 staining was present in 23 of 28 (82%, including strong positivity in the cytokeratin-reactive cases). Staining for S-100 protein was strong in all cases. No staining was seen for CEA (monoclonal). CEA immunoreactivity is seen in a significant number of metastatic malignant melanoma cases. This may be due to CEA expression by tumor cells, or crossreactivity of the polyclonal antibody with substances such as nonspecific crossreacting antigen (NCA) that share antigenic sites with CEA. These findings emphasize the need for care in interpreting immunohistochemical results. Immunohistochemical evaluation of CEA should not be made alone, but only as part of a diagnostic antibody panel.

Antibodies, Neoplasm↗
PubMed1991

45,X/47,XYY mosaicism: clinical discrepancy between prenatally and postnatally diagnosed cases.

45,X/47,XYY mosaicism is a rare chromosomal disorder with clinical information limited to 11 postnatal cases in the literature and with uncertainty regarding prenatal prediction of phenotype and prognosis. We report on 7 new cases of 45,X/47,XYY mosaicism, three detected prenatally and 4 diagnosed postnatally. A clinical comparison of the cases of 45,X/47,XYY mosaicism is presented together with a literature review.

Amniocentesis↗
PubMed1991

Hemangiopericytoma of the spleen.

A splenic tumor is reported with the light microscopic, immunohistochemical, and ultrastructural features of a hemangiopericytoma. The findings in this case are compared with the only previously reported splenic hemangiopericytoma. Differences in the clinical presentation and the gross appearance of the two cases are described, and similarities in the microscopic features are discussed.

Adult↗
PubMed1991

Brain abscess in glycogen storage disease type Ib.

Neutropenia, neutrophil dysfunction, and recurrent infections are important manifestations of glycogen storage disease type Ib. We report here a child who has had adequate metabolic control, but developed brain abscess, an infection not previously described in this disease. This case provides further evidence that the neutrophil anomaly is related to the basic enzyme defect, not secondary to the metabolic derangement.

Brain Abscess↗
PubMed1990

Fine-needle aspiration cytology of granulocytic sarcoma and myeloid metaplasia.

The fine-needle aspiration (FNA) cytology of two cases of granulocytic sarcoma involving the breast is reported along with the FNA cytology of one case of myeloid metaplasia (extramedullary hematopoiesis) involving an axillary lymph node. Two patients had known myeloproliferative disorders, while granulocytic sarcoma of the breast was the initial presentation of an unsuspected acute granulocytic leukemia in the other patient. Diff-Quik-stained preparations aided in the diagnosis of all three cases. Immunoperoxidase stains for factor VIII-related antigen helped confirm the megakaryocytic differentiation of the cells in the FNA cytology of myeloid metaplasia. Electron microscopic (EM) examination performed on the aspirated material also showed megakaryocytic differentiation of the bizarre cells. FNA cytology can make a specific diagnosis of granulocytic sarcoma and myeloid metaplasia. The workup of these unusual extramedullary myeloproliferative masses was aided when immunocytochemistry and EM were performed on the aspirated material.

Adult↗
PubMed1990

Fine-needle aspiration cytology of hematopoietic lesions from multiple sites.

We reviewed 130 fine-needle aspiration (FNA) biopsies from 118 patients with a variety of benign and malignant hematopoietic lesions. There were 74 (57%) malignant, 45 (35%) benign, and 11 (8%) atypical diagnoses. Immunocytochemistry of the aspirated material was performed in 47 (36%) and electron microscopy in 4 (3%) of the cases. FNA cytology was utilized to make a primary hematopoietic malignant diagnosis in approximately half of the cases and to confirm recurrence in the remainder. The malignant cases included non-Hodgkin's lymphoma. Hodgkin's disease, medullary and extramedullary plasmacytoma, and granulocytic sarcoma. Forty-two malignant cases had either previous or follow-up surgical biopsy with no false-positive diagnoses. Of the 11 atypical cases, seven had surgical confirmation with five malignant and two benign diagnoses. The benign hematopoietic lesions correctly identified included acute and chronic lymphadenitis, granulomatous processes, and eosinophilic granuloma. Only 5 of the 45 benign FNA biopsies had surgical pathology follow-up, with no false-negative diagnoses. The most commonly aspirated sites were lymph nodes (71%), although hematopoietic lesions were correctly identified in a number of extranodal locations, including soft tissue (8%), abdominal viscera (6%), lungs (5%), mediastinum (2.5%), bone (3%), and thyroid, salivary gland, and breast (1.5% each). This study demonstrates the clinical utility and diagnostic accuracy of FNA cytology in the evaluation of benign and malignant hematopoietic disorders from multiple sites. Ancillary studies performed on the aspirated material aided in making a specific and accurate diagnosis.

Adolescent↗
PubMed1990

Utility of peanut agglutinin (PNA) in the diagnosis of squamous cell carcinoma and keratoacanthoma.

Lectins are glycoproteins that bind to specific carbohydrate groups on cell surfaces. Peanut lectin (PNA) binds to carbohydrates on the membranes of normal keratinocytes. Recently, some authors have proposed that PNA may be a useful marker to help differentiate keratoacanthomas from well-differentiated squamous cell carcinomas of the skin. We studied a total of 34 skin biopsy specimens, including 11 keratoacanthomas, 15 well-differentiated squamous cell carcinomas, and 8 poorly differentiated squamous cell carcinomas, using peanut lectin with the avidin-biotin complex (ABC) peroxidase technique. All keratoacanthomas demonstrated uniform positive membrane staining of keratinocytes, which was identical to PNA staining in normal skin. Keratinocytes in 80% of the well-differentiated squamous cell carcinomas and keratinocytes in all the poorly differentiated squamous cell carcinomas did not stain. With prior digestion by neuraminidase, however, positive membrane staining for PNA was demonstrated in the squamous cells of all well-differentiated squamous cell carcinomas and all but one case of the poorly differentiated squamous cell carcinomas. Our results support the efficacy of PNA in most cases as a marker to aid in the often difficult histologic differentiation of keratoacanthoma from well-differentiated squamous cell carcinoma. Our findings also support those of previous authors who suggested that the negative PNA stain of malignant squamous cells is not the result of a lack of PNA receptors, but is due instead to a masking of receptor sites by terminal sialic acid residues.

Arachis↗
PubMed1988

Malignant rhabdoid skin tumor: an uncommon primary skin neoplasm. Ultrastructural and immunohistochemical analysis.

Rhabdomyosarcomatoid renal tumors were initially described as a subset of tumors in the National Wilms Tumor Study that had light microscopic features similar to rhabdomyosarcomas. Subsequent studies failed to reveal evidence of muscle differentiation, thus the genesis of the term "rhabdoid" tumor. Such renal tumors are rapidly lethal. Recent reports suggest the occurrence of tumors with similar morphology in other anatomic sites. We wish to report a primary malignant rhabdoid tumor of the facial skin with detailed immunohistochemical and ultrastructural studies. Vimentin was expressed in the tumor cells, but there was no immunoreactivity for cytokeratins, neurofilaments, muscle actin, synaptophysin, S-100, melanoma antigen HMB-45, epithelial membrane antigen, neuron specific enolase, Leu-7, leucocyte common antigen or lysozyme/alpha-1-antitrypsin. Ultrastructure revealed typical whorled cytoplasmic aggregates of intermediate filaments. These studies along with a literature review reveal the heterogeneous immunohistochemical profiles of these tumors with common morphologic features. While the histogenesis of these tumors remain uncertain, it is necessary to recognize that these aggressive neoplasms may occur primarily in the skin.

Forehead↗
PubMed1987

Recurrent melanocytic nevi: clinical and histologic review of 175 cases.

Pigmented nevi, if excised incompletely, often recur and occasionally cause concern to the patient and the physician. In this study of 175 recurrent nevi from 173 patients, the clinical, gross, and microscopic features of recurrent nevi are described and criteria for diagnosis are developed. Rarely, recurrent nevi have atypical features that suggest malignant melanoma. The differential diagnosis entails clinical and histologic criteria that are presented.

Adolescent↗
PubMed1986

The role of fine-needle aspiration biopsy in the rapid diagnosis and management of thyroid neoplasm.

This report describes our 5-year experience with fine-needle aspiration (FNA) biopsy of the thyroid in a 560-bed teaching hospital. Three hundred nine FNA biopsies were performed primarily by one endocrinologist and interpreted by several pathologists. Analysis of the data reveals the sensitivity of the procedure is 93%, specificity is 95.1%, and the positive and negative predictive values are 88.9% and 96.5%, respectively. This data confirms the diagnostic accuracy of FNA biopsy. Complications were seen in 6 of 309 cases (1.9%) and were relatively mild. Nearly 75% of the cases in the series were cytologically diagnosed as nonneoplastic. Fine-needle aspiration biopsy identified 19.4% of the cases needing surgery, of which 72% had neoplastic nodules, confirming the selection role of the procedure. The management of thyroid nodules is discussed and a selective review of the FNA literature is presented. The authors believe that our experience rebuts the argument that special referral centers are needed to interpret the cytologic material. Several well trained surgical pathologists can become proficient in interpreting the FNA biopsies without significant loss in accuracy, and thereby render a definite diagnosis in the vast majority of the cases. Accordingly, the authors recommend FNA of the thyroid as the initial diagnostic test in the evaluation of thyroid nodules.

Adenocarcinoma↗