Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027627 (metastases)
 103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The lymphocytes that accompany thymomas express an immature T-cell phenotype, as usually demonstrated by CD1 or TdT immunoreactivity. Even when thymomas metastasize or occur in ectopic sites, the infiltrating T lymphocytes show this unique immature phenotype, contrasting with thymic and nonthymic carcinomas, in which the infiltrating T lymphocytes typically show a mature phenotype (CD1 and TdT negative). Therefore, the presence of an immature T-cell population in an epithelial tumor strongly supports a diagnosis of thymoma. The availability of an antibody that consistently marks immature T-cells in routine paraffin sections would be of great help in the study of thymic tumors. In this report, we describe the use of MIC2 antibody (013), which has been widely used for the diagnosis of Ewing's sarcomas and peripheral primitive neuroectodermal tumors because it intensely stains thymocytes. Immunohistochemical staining was performed on paraffin sections of normal/hyperplastic thymus (18 cases), thymoma (62 cases), thymic carcinoma (nine cases), tumors showing borderline features between thymoma and thymic carcinoma (three cases), and ectopic hamartomatous thymoma (two cases). T-cell and B-cell antibodies were also applied to aid in the interpretation. In the normal thymus, almost all lymphocytes in the cortex stained with 013, whereas fewer than 5% of those in the medulla were 013 positive. In thymomas, including the three ectopic thymomas and the single case of metastatic thymoma, most lymphocytes were 013 positive, except the spindle-cell foci (medullary thymoma or medullary component of mixed thymoma), in which the percentage of 013-positive lymphocytes was lower (5-30%). Within the pale foci of "medullary differentiation" and the perivascular spaces of lymphocyte-rich thymomas, few lymphocytes showed 013 positivity, indicating that the T lymphocytes in these areas were more mature. None of the thymic carcinomas harbored 013-positive lymphocytes. Among the three cases of borderline thymoma/thymic carcinoma, only one harbored 013-positive lymphocytes. The 013-positive lymphocytes were not seen in the ectopic hamartomatous thymomas. In normal lymph nodes and nonthymic carcinomas studied as controls, there were no or at most small numbers of isolated 013-positive lymphocytes. We conclude that interpreted in the proper context, MIC2 antibody can serve as a useful marker of immature T-cells and thus help in the confirmation of a diagnosis of thymoma in small biopsy specimens, ectopic thymoma, or metastatic thymoma; in the distinction between invasive thymoma and thymic carcinoma; and in the classification of thymomas.
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PMID:The MIC2 antibody 013. Practical application for the study of thymic epithelial tumors. 757 70

Type AB thymomas are considered to be nonaggressive tumors, and the great majority are classified as Masaoka stage I or II. This report presents a case with Masaoka stage I and type AB thymoma, which metastasized to the brain 2 years 5 months after removal of the primary tumor. The original mediastinal lesion was adhesive but not invasive to the lung. The patient is now alive with multiple tiny pulmonary metastases 3 years after complete resection of the brain metastasis. Some reports of recurrent thymomas have suggested that the presence of peritumoral adherence to the adjacent structures might be a risk factor for recurrence in patients with such noninvasive thymomas. During the development of fibrosis which thus causes adhesion, the tumor may have an increased chance to metastasize because of the increased vessels and lymphatics.
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PMID:Type AB thymoma with brain metastasis: Report of a case. 2192 73

A 58-year old man with thymoma and myasthenia gravis (MG) had undergone thymectomy 8 years ago with histopathologically confirmed non-invasive WHO-type AB thymoma. After 5 years of complete remission, symptoms of MG resurfaced, and a recurrent anterior mediastinal mass was detected for which he received radiotherapy. He presented to us 3 years later with productive cough and exertional dyspnoea; the positron emission tomography-computed tomography scan revealed a metabolically active pulmonary nodule in the right lung as the only site of disease for which a right lower lobectomy was done. Microscopy established an intrapulmonary WHO-type B2 thymoma and the patient is currently asymptomatic on steroids, anticholinesterase and immunosuppressant therapy. We discuss the variable and unpredictable course of thymomas; the possibility of transformation into more aggressive types with each recurrence, association with recurrent MG post-thymectomy and presentation several years later with metastatic disease.
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PMID:Unusual clinical behaviour of thymoma with recurrent myasthenia gravis. 2237 19

We report a very rare case of combined thymic carcinomas: undifferentiated thymic carcinoma coexisting with type AB thymoma. The precise mechanism underlying the coexistence of these tumors remains unknown. Therefore, we used clonality analysis to ascertain whether the two tumors were clonally related. A 63-year-old woman with thyroid cancer visited our hospital. Chest computed tomography also revealed an anterior mediastinal tumor. The patient was treated with total thyroidectomy and surgery for mediastinal tumors together with left upper lobe partial resection. The mediastinal tumor was pathologically diagnosed as undifferentiated thymic carcinoma coexisting with type AB thymoma. Multiple pulmonary metastases were detected in the patient and stage IV disease was diagnosed. The tumor was treatment-resistant, and the patient received fourth-line chemotherapy. We conducted clonality analysis using an improved human androgen receptor gene-amplification assay that involves random X-chromosome inactivation through methylation, followed by methylated gene-specific PCR amplification after sample DNA digestion with HpaII, a methylation-sensitive restriction enzyme. Clonality analysis demonstrated identical X-chromosome inactivation in cells present in both thymoma and thymic carcinoma areas, and thus revealed clonal proliferation. The two lesions in the patient might have arisen through the transformation of a preexisting thymoma into a more malignant lesion.
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PMID:Clonality analysis performed using human androgen receptor assay in a rare case of undifferentiated thymic carcinoma coexisting with type AB thymoma. 2732 90

Type AB thymoma associated with multiple metastases is rarely encountered. This paper describes the therapeutic effect of new radiotherapy, helical tomotherapy (TOMO), in a thymoma patient with multiple metastases. A male patient aged 52 was diagnosed as type AB thymoma with multiple metastases. Two-cycle chemotherapy was administered as the primary therapy. The efficacy evaluation indicated progressive disease (PD), so radiotherapy was added to the initial treatment. The re-evaluation of efficacy indicated PD under chemotherapy and partial response (PR) in the radiotherapy area, so the latter treatment was changed to TOMO. The TOMO treatment was effective. However, due to the severe bone marrow suppression, the radiotherapy was stopped, and the patient was discharged. We concluded that the development of type AB thymoma associated with multiple metastases was fast, and the patient was sensitive to radiotherapy but not chemotherapy. Thus, TOMO can be selected as the primary palliative therapeutic regimen for chemotherapy-resistant thymoma patients, but the patient tolerance of TOMO requires careful evaluation and further clinical study.
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PMID:A case of chemorefractory metastatic type AB thymoma sensitive to helical tomotherapy. 3135 41

Thymomas are rare anterior mediastinal tumors that originate in the epithelial cells of the thymus and have a rare propensity to metastasize to extrathoracic locations unless it is a histologic high-grade neoplasm (type B and above). We describe a case of 50-year-old woman diagnosed with type AB thymoma and the role of 18F-fluorodeoxyglucose positron emission tomography-computed tomography in accurate delineation of extrathoracic metastases during initial staging.
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PMID:Low-Grade Thymoma with Osseous and Pulmonary Metastases: Role of 18F-Fluorodeoxyglucose Positron Emission Tomography-Computed Tomography in Initial Staging. 3235 Dec 82