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N G Ordóñez

Publications and source records attributed to N G Ordóñez.

At least 19 recordsLinked to original sources
PubMed2002

Characterization of foam cells in nipple aspirate fluid.

Foam cells with abundant vacuolated cytoplasm are prominent in most samples of spontaneous nipple discharge, nipple aspirate fluid, and ductal lavage. Although several investigators have attempted to characterize these cells, there is no consensus about whether these cells are derived entirely from macrophages or from both ductal epithelial cells and macrophages. Using immunocytochemical methods, we studied 20 paired specimens of nipple aspirate fluid containing abundant foam cells obtained from the involved breast of women with in situ or invasive carcinoma and from the contralateral normal breast. We used a cocktail of anticytokeratin antibodies including AE1, AE3, and CAM5.2 and the macrophage marker KP1 (CD68). In addition, we examined samples by electron microscopy. The foam cells were consistently negative for cytokeratin and positive for CD68. In every case electron microscopy of these cells revealed irregular outlines with short cytoplasmic processes. The cytoplasm was abundant and contained numerous lysosomes, a small Golgi complex, lipid droplets, mitochondria, and short profiles of rough endoplasmic reticulum. There was no evidence, however, of cell junctions or tonofilaments. The immunocytochemical and electron microscopic findings of our study together clearly support a macrophage derivation for foam cells in nipple aspirate fluid.

Antigens, CD↗
PubMed2001

Primary signet-ring cell carcinoma of lung: immunohistochemical study and comparison with non-pulmonary signet-ring cell carcinomas.

Signet-ring cell carcinoma (SRCC) of lung is a rare variant of pulmonary adenocarcinoma. In view of this rarity, the question of whether an SRCC is primary pulmonary or metastatic arises frequently because the majority of SRCCs seen in lung are metastatic tumors having arisen in stomach, colon, or breast. On routine histologic examination it is difficult to distinguish between pulmonary SRCC from SRCC metastasizing from other organs. Thyroid transcription factor-1 (TTF-1) is a homeodomain-containing transcription factor that is almost exclusively expressed in thyroid and pulmonary epithelial cells. TTF-1 expression has been demonstrated in various neoplasms of lung; however, the expression of TTF-1 in SRCCs has not been investigated so far. In the present study, using an immunoperoxidase staining procedure on paraffin sections, we investigated the expression of TTF-1, cytokeratin 7, cytokeratin 20, and villin (a specific marker expressed in tumors of the digestive tract, renal proximal tubules, and hepatic bile ducts) in 32 SRCCs from various organs (17 lung, 5 breast, 5 stomach, and 5 colon). Fourteen (82.4%) of 17 pulmonary SRCCs exhibited TTF-1 positivity, whereas none of the SRCCs of other organs were positive for TTF-1. A cytokeratin profile (CK7+/CK20-) was identified in 94.1% of pulmonary SRCC, and although it differed from the profile exhibited in colonic SRCCs (CK7-/CK20+), a similar profile was seen in breast SRCCs and some SRCCs arising in the stomach. Villin was identified in 29.4% of pulmonary SRCCs and 20% (one case) arising in the breast. Although the pattern of villin immunostaining exhibited by nondigestive tract SRCCs (cytoplasmic) differed from those of digestive tract SRCCs (membranous), distinguishing between the two groups based on their pattern of immunostaining alone would be difficult. The results of this study indicate that TTF-1 is expressed in a high percentage of pulmonary SRCCs and is very specific and that TTF-1 would be extremely valuable in distinguishing pulmonary SRCCs from those arising in other organs.

Biomarkers, Tumor↗
PubMed2001

Pancreatic acinar cell carcinoma.

Acinar cell carcinomas (ACCs) are rare neoplasms that represent less than 2% of all exocrine tumors of the pancreas. Although they occur more often in adults between the 5th and 7th decades of life, a few cases have been reported in children. Histologically, ACCs can resemble islet cell tumors, but they differ in their ultrastructural and immunohistochemical features. Although ACCs present a bland histology, they are highly malignant and the survival of patients with these tumors, even though better than that of those with ductal cell carcinomas, is generally poor.

Biomarkers, Tumor↗
PubMed2000

Fine-needle aspiration cytology of a case of oncocytic adrenocortical carcinoma.

We report on the results of fine-needle aspiration cytology of a case of oncocytic adrenocortical carcinoma in a 39-yr-old man. The tumor invaded the inferior vena cava and extended up to the right atrium. Aspirate smears were very cellular and showed a monomorphic population of large polyhedral cells with abundant granular cytoplasm, predominantly distributed singly. Mitotic activity was inconspicuous, and there was no necrosis. Immunohistochemically, the tumor cells were positive for vimentin, cytokeratin, and p53, and negative for synaptophysin, chromogranin, inhibin, and S-100. Ultrastructurally, the cytoplasm of the tumor cells was packed with mitochondria. The patient underwent left radical nephrectomy as well as a combined cardiopulmonary bypass, with atriotomy and resection of the tumor from the right atrium and inferior vena cava. Three months of postoperative follow-up were uneventful.

Adrenal Cortex Neoplasms↗
PubMed2000

Transitional cell carcinomas of the ovary and bladder are immunophenotypically different.

AIMS: Transitional cell carcinoma (TCC) of the ovary is a subtype of ovarian cancer whose main characteristic is its histological resemblance to TCC of the bladder. Thrombomodulin (TM), a surface glycoprotein commonly expressed in normal and neoplastic urothelium, has been proven to be a good marker for TCC of the bladder. To better define the phenotype of TCC of the ovary, we investigated TM, cytokeratin 20 and carcinoembryonic antigen (CEA) expression in 15 TCCs of the ovary and compared their phenotype with that of 20 TCCs of the bladder, and 20 serous and 10 endometrioid carcinomas of the ovary. METHODS AND RESULTS: Immunostaining was performed on formalin-fixed, paraffin-embedded tissue sections using the avidin-biotin-peroxidase complex method. All 20 TCCs of the bladder stained for TM and cytokeratin 20, and 13 stained for CEA. None of the TCCs of the ovary reacted for TM or cytokeratin 20, and only two expressed CEA. All of the serous and endometrioid carcinomas were negative for TM and cytokeratin 20. CEA positivity was observed in two of the serous carcinomas, but in none of the endometrioid carcinomas. CONCLUSION: The immunophenotype of TCC of the ovary is similar to that of other surface carcinomas of the ovary, but differs from that of TCC of the bladder. Since immunohistochemical procedures are often used in the diagnosis and classification of both primary and metastatic tumours, it is important to be aware of these differences in immunophenotype.

Biomarkers, Tumor↗
PubMed2000

Value of thyroid transcription factor-1, E-cadherin, BG8, WT1, and CD44S immunostaining in distinguishing epithelial pleural mesothelioma from pulmonary and nonpulmonary adenocarcinoma.

The distinction between malignant pleural mesotheliomas and adenocarcinomas, particularly those originating in the lung, is a difficult diagnostic problem that can be facilitated by the use of immunohistochemical markers. In this study, the immunoreactivity of thyroid transcription factor-1 (TTF-1), E-cadherin, BG8, WT1, and CD44S was investigated in 50 epithelial mesotheliomas, and 40 pulmonary and 95 nonpulmonary adenocarcinomas. After analyzing the results, it was concluded that E-cadherin and BG8 are useful markers for distinguishing between epithelial mesotheliomas and adenocarcinomas of various origins, including the lung. Because TTF-1 expression is found almost exclusively in adenocarcinomas of the lung but is absent in mesotheliomas, immunostaining for this marker is particularly useful for distinguishing between these two malignancies. Although WT1 immunostaining may also be useful, its value, as determined in this study, is lower than that reported by other investigators. CD44S immunostaining does not have any practical value in discriminating between epithelial mesothelioma and lung adenocarcinoma.

Adenocarcinoma↗
PubMed2000

Epithelial mesothelioma with deciduoid features: report of four cases.

Deciduoid mesothelioma is the designation given to an unusual morphologic variant of epithelial mesothelioma that closely simulates exuberant ectopic decidual reaction. Because all four previously reported cases involved the peritoneum and occurred in young women without a history of asbestos exposure, it was suggested that deciduoid mesothelioma was a subtype of epithelial mesothelioma characterized by its unique morphology, that it affects a distinct patient population, and that it is unrelated etiologically to asbestos. The author reports four cases of mesothelioma with deciduoid features, all of which originated in the pleura. Three of the patients were men and one was a woman. Their ages ranged from 46 to 78 years (mean age, 67 yrs). Two of the patients had a history of asbestos exposure. These findings indicate that this morphologic variant of mesothelioma is not limited to a specific patient population nor is it restricted to the peritoneum.

Aged↗
PubMed2000

Value of thyroid transcription factor-1 immunostaining in distinguishing small cell lung carcinomas from other small cell carcinomas.

The distinction between small cell lung carcinoma (SCLC) and small cell carcinomas of other sites is difficult by routine histology. Thyroid transcription factor-1 (TTF-1) is a homeodomain-containing transcription factor that is selectively expressed in thyroid and pulmonary epithelial cells. TTF-1 expression has also been demonstrated in adenocarcinomas of the thyroid and lung, and SCLC. However, the value of TTF-1 immunostaining in discriminating between SCLC and nonpulmonary small cell carcinomas has not been investigated. In the present study using an immunoperoxidase staining procedure on paraffin sections, we investigated the expression of TTF-1 and cytokeratin 20 (CK20), a marker that has previously been demonstrated in small cell carcinomas of the skin (Merkel cell carcinomas), in 82 small cell carcinomas from a wide variety of sites (28 lung, 18 skin, 12 gastrointestinal tract, 8 sinonasal, 5 bladder, 3 prostate, 3 uterine cervix, 2 thyroid, 2 salivary gland, and 1 pancreas). Twenty-seven (96%) of the 28 SCLCs were positive for TTF-1. Among the nonpulmonary small cell carcinomas, two tumors of the gastrointestinal tract, one of the bladder, and one of the uterine cervix exhibited TTF-1 positivity. Sixteen (89%) of the 18 Merkel cell carcinomas and one SCLC were CK20-positive. All other small cell carcinomas were negative for this marker. These results indicate that although TTF-1 is not a specific marker for SCLC, it may assist in distinguishing SCLC from some nonpulmonary small cell carcinomas, particularly Merkel cell carcinoma, especially when it is used in conjunction with CK20.

Biomarkers, Tumor↗
PubMed2000

Thyroid transcription factor-1 is a marker of lung and thyroid carcinomas.

Thyroid transcription factor-1 (TTF-1) is a tissue specific transcription factor expressed in epithelial cells of the thyroid and lung, as well as in certain areas of the brain. Recent investigations have shown that TTF-1 is also commonly present in a wide variety of thyroid and lung tumors. Because of its restrictive expression, TTF-1 is a useful immunohistochemical marker in the diagnosis of tumors of thyroid or lung origin.

Biomarkers, Tumor↗
PubMed2000

Localized (solitary) fibrous tumor of the pleura.

Clinical, light microscopic, ultrastructural, and immunocytochemical features of localized fibrous tumor of the pleura are reviewed. The differential diagnosis of the benign tumors can be uncomplicated, but atypical variants and malignant forms require the exclusion of other tumors included in the broad array of spindle cell neoplasms that can arise in or extend to a serosal surface. Electron microscopy is useful, but immunostaining procedures offer more extensive and reliable help in reaching the correct diagnosis. Tumors histologically similar to localized fibrous tumor of the pleura have been described in a number of extraserosal locations. Some localized fibrous tumors may be true fibromas, whereas the typical pleural tumor appears to arise from the subserosal mesenchymal cell and is composed of CD34-positive cells which are more primitive in their morphology than mature fibroblasts.

Adolescent↗
PubMed1999

The immunohistochemical diagnosis of epithelial mesothelioma.

Although it is generally accepted that immunohistochemistry can assist in distinguishing between epithelial mesotheliomas and metastatic adenocarcinomas to the serosal membranes, a great deal of controversy exists regarding not only the practical value of some of the markers currently used, but also which should be included as part of the routine diagnostic panel. Until recently, these panels consisted primarily of antibodies that stained adenocarcinomas but not mesotheliomas. Over the last few years, however, markers that are commonly expressed in mesotheliomas but not in adenocarcinomas have been recognized. The focus of this review is on those markers for which there is an indication that they have a practical use in the diagnosis of mesothelioma. Special emphasis is placed on those which have been most recently recognized.

Adenocarcinoma↗
PubMed1999

Alveolar soft part sarcoma: a review and update.

Alveolar soft-part sarcoma (ASPS) is one of the most unusual of the soft tissue sarcomas. Although it most commonly arises in the fascial planes or skeletal muscles of the lower extremities in adults, and in the head and neck region in children, it has also been documented in extraskeletal muscle locations, especially the female genital tract. Despite extensive investigation, the histogenesis of ASPS continues to be an unsettled issue a half century after its description. The most significant morphologic features are the organoid pattern and the ultrastructural demonstration of a secretory activity that ends in the formation of the characteristic crystals. Early suggestions that it was related to paragangliomas or had a Schwann cell derivation have been discounted. More recently, a possible skeletal muscle origin has been favored based on the immunohistochemical demonstration of various muscle-associated proteins, especially desmin. However, a report of immunoreactivity for the myogenic regulatory protein MyoD1 has not been confirmed in subsequent studies. Although some immunohistochemical studies have recently indicated that ASPS may have muscle differentiation, there is presently no conclusive evidence that it represents a unique type of muscle-derived tumor.

Adolescent↗
PubMed1999

Granular cell tumor: a review and update.

The histogenesis of granular cell tumor (GCT) has been a source of controversy since its recognition as an entity by Abrikossoff in 1926. These lesions can occur in virtually any location. Benign GCTs are not uncommon, but malignant ones are rare and at times difficult to diagnose. The main morphologic feature is the granularity of the cytoplasm which is caused by a massive accumulation of lysosomes. Early suggestions that GCT may have a myoblastic origin have been discounted and use of the term granular cell myoblastoma as a designation for this tumor is discouraged. Although most investigators currently favor a Schwann cell derivation based on immunohistochemical and electron microscopic findings and advocate the designation of granular cell schwannoma, some differences exist between schwannomas and GCTs in their ultrastructural characteristics and the expression of some immunohistochemical markers. Other investigators believe that GCT is not a specific entity but rather a degenerative change that can occur not only in Schwann cells but also in a variety of other normal and neoplastic cells. Until more information becomes available, particularly that derived from cytogenetic studies, this lesion should be considered a separate entity and the descriptive designation of granular cell tumor continues to be appropriate.

Biomarkers↗
PubMed1999

Benign nevus cell aggregates in the thymus: a case report.

Aggregates of benign nevus cells occurring in lymph nodes are a well-described incidental finding. Nevus cell aggregates (NCAs) can mimic foci of metastatic carcinoma or other disease processes, so the surgical pathologist should be familiar with this lesion. The purpose of this report is to describe the potential diagnostic difficulties created by benign NCAs within the thymus of a 32-year-old man with dysplastic nevus syndrome and malignant melanoma involving mediastinal lymph nodes and the right lung. Morphologically, the NCAs in this case elicited the differential diagnoses of metastatic melanoma and thymoma. Immunohistochemical studies helped to establish the correct diagnosis by demonstrating reactivity for S-100 protein and negative staining for keratin and HMB-45. Unlike malignant melanomas, NCAs show no p53 protein immunoreactivity, and low proliferative activity was detected by Ki-67 antigen immunostaining. Although melanocytic cells were rarely reported in thymic neoplasms, we are not aware of any previous reports of NCAs occurring in the normal thymus.

Adult↗
PubMed1998

Altered p53 is associated with aggressive behavior of chondrosarcoma: a long term follow-up study.

BACKGROUND: p53 is a major tumor suppressor gene that has been implicated in the biology of a variety of human neoplasms, including some that affect the skeleton. Recent studies based on small numbers of cases have shown that overexpression or alteration of the p53 gene is frequently present in high grade, clinically aggressive chondrosarcomas of bone. In this study, the authors addressed the relation between overexpression and alteration of the p53 gene and the clinical aggressiveness of chondrosarcoma in a large series of patients for whom long term follow-up data were available. METHODS: The authors analyzed the expression and/or alteration of the p53 gene in 158 cases of chondrosarcoma of bone using immunohistochemistry, single-strand conformation polymorphism, and direct sequencing. They then related the findings to various clinicopathologic parameters and long term follow-up data. RESULTS: The presence of overexpression and/or structural alterations of the p53 gene was documented in 38.1% of chondrosarcomas of bone. A statistically significant correlation was observed between overexpression or alteration of the p53 gene and both the histologic grade of the tumor and the presence of metastasis. The probability of local recurrence free, metastasis free, and overall survival was significantly higher for patients with no overexpression or alteration of p53 than for patients with p53 overexpression or alteration. CONCLUSIONS: Overexpression or alteration of the p53 gene is an important predictor of aggressive clinical behavior in chondrosarcoma of bone.

Adolescent↗
PubMed1998

Electron microscopy in tumor diagnosis: indications for its use in the immunohistochemical era.

The electron microscope reveals much more information on tumor cell structure than can be obtained with the light microscope, and some of the data are useful in diagnostic studies. In this review, major contributions of electron microscopy in the main tumor categories are discussed. To select between immunocytochemistry and electron microscopy, the probable contributions of each in the context of the particular case must be assessed. Usually, electron microscopy will only be requested after a battery of immunostaining procedures has been performed and found to be insufficient, but there are occasions when ulstrastructural study is logically the first choice after routine light microscopy. It is worth taking tissue for possible electron microscopy from any tumor that is known or anticipated to be a diagnostic problem.

Biomarkers, Tumor↗
PubMed1998

CA 125 production in desmoplastic small round cell tumor: report of a case with elevated serum levels and prominent signet ring morphology.

Serum assays for CA 125 are often used in the diagnosis and follow-up of patients with gynecologic neoplasms. A case of a 34-year-old woman with desmoplastic small round cell tumor (DSRCT) having an unusual morphology, including the presence of a signet ring cell component, and high serum CA 125 levels that was initially diagnosed as poorly differentiated carcinoma of the ovary is herein reported. Ultrastructurally, the signet ring appearance was shown to be the result of either the presence of intracytoplasmic vacuoles or dilatation of the intercellular space. Immunoperoxidase staining showed strong reactivity for desmin, keratin, vimentin, and CA 125. Immunohistochemical studies were performed on six additional DSRCTs but only two showed focal staining for CA 125. Because the patient's CA 125 serum level decreased after she received chemotherapy and her tumor was removed, and it became elevated again when the disease recurred, it is possible that CA 125 could be used as a marker of persistent and recurrent disease in those uncommon cases of DSRCT in which there are elevated serum levels of this marker at the onset of treatment.

Adult↗