• Journal of Yeungnam Medical Science
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• v.27 no.2
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• pp.98-104
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• 2010

Primary anterior mediastinal neoplasms comprise a diverse group of tumors and account for 50% of all mediastinal masses. Thymic epithelial neoplasm are most common and classified into thymoma, invasive thymoma, and thymic carcinoma. Neuroendocrine differentiation of thymic epithelial neoplasm are rare malignancies. Germ cell tumor (GCT) is second most common anterior mediastinal tumor and most of them are mature cystic teratoma. Malignant mediastinal GCT are rare than benign. Primary thoracic lymphoma is rare than thoracic involvement of systemic lymphoma and most common location of primary thoracic lymphoma is anterior mediastinum. The clinical and radiologic appearance of the most common masses are reviewed.

• Molecules and Cells
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• v.38 no.6
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• pp.548-561
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• 2015

By combining conventional single cell analysis with flow cytometry and public database searches with bioinformatics tools, we extended the expression profiling of thymic stromal cotransporter (TSCOT), Slc46A2/Ly110, that was shown to be expressed in bipotent precursor and cortical thymic epithelial cells. Genome scale analysis verified TSCOT expression in thymic tissue- and cell type- specific fashion and is also expressed in some other epithelial tissues including skin and lung. Coexpression profiling with genes, Foxn1 and Hoxa3, revealed the role of TSCOT during the organogenesis. TSCOT expression was detected in all thymic epithelial cells (TECs), but not in the $CD31^+$endothelial cell lineage in fetal thymus. In addition, ABC transporter-dependent side population and Sca-$1^+$ fetal TEC populations both contain TSCOT-expressing cells, indicating TEC stem cells express TSCOT. TSCOT expression was identified as early as in differentiating embryonic stem cells. TSCOT expression is not under the control of Foxn1 since TSCOT is present in the thymic rudiment of nude mice. By searching variations in the expression levels, TSCOT is positively associated with Grhl3 and Irf6. Cytokines such as IL1b, IL22 and IL24 are the potential regulators of the TSCOT expression. Surprisingly, we found TSCOT expression in the lung is diminished in lung cancers, suggesting TSCOT may be involved in the suppression of lung tumor development. Based on these results, a model for TEC differentiation from the stem cells was proposed in context of multiple epithelial organ formation.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.8
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• pp.3457-3460
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• 2014

Background: Thymomas and thymic carcinomas are rare malignancies and devising clinically effective molecular targeted therapies is a major clinical challenge. The aim of the study was to analyze BLC2 and vascular endothelial growth factor receptor (VEGFR) expression and KRAS and EGFR mutational status and to correlate them with the clinical characteristics of patients with thymomas and thymic carcinomas. Materials and Methods: A total of 62 patients (mean age: $50.4{\pm}13.2$ years) with thymomas and thymic carcinomas were enrolled. The expression of BLC2 and VEGFR in tumor cells and normal tissues was evaluated by RT-PCR. The mutational status of the KRAS and EGFR genes was investigated by PCR with sequence specific primers. Results: The BLC2 and VEGFR expression levels did not differ significantly between tumor and normal tissues. Moreover, there were no clearly pathogenic mutations in KRAS or EGFR genes in any tumor. None of the molecular markers were significantly related to clinical outcomes. Conclusions: Changes in levels of expression of BLC2 and VEGFR do not appear to be involved in thymic tumorigenesis. Moreover, our data suggest that KRAS and EGFR mutations do not play a major role in the pathogenesis of thymomas and thymic carcinomas.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.11
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• pp.5581-5585
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• 2012

Objective: To explore the relationship between computed tomography (CT) manifestations of thymoma and its WHO pathological classification. Methods: One hundred and five histopathologically confirmed cases were collected for their pathological and CT characteristics and results were statistically compared between different pathological types of thymoma. Results: Tumor size, shape, necrosis or cystic change, capsule integrity, invasion to the adjacent tissue, lymphadenopathy, and the presence of pleural effusion were significantly different between different pathological types of thymomas (P<0.05). Type B2, B3 tumors and thymic carcinomas were greater in size than other types. More than 50% of type B3 tumors and thymic carcinomas had a tumor size greater than 10 cm. The shape of types A, AB, and B1 tumors were mostly round or oval, whereas 75% of type B3 tumors and 85% of thymic carcinomas were irregular in shape. Necrosis or cystic change occurred in 67% of type B3 thymomas and 57% of thymic carcinomas, respectively. The respective figures for capsule destruction were 83% and 100%. Increases in the degree of malignancy were associated with increases in the incidence of surrounding tissue invasion: 33%, 75%, and 81% in type B2, type B3, and thymic carcinomas, respectively. Pleural effusion occurred in 48% of thymic carcinomas, while calcification was observed mostly in type B thymomas. Conclusions: Different pathological types of thymic epithelial tumors have different CT manifestations. Distinctive CT features of thymomas may reflect their pathological types.

• Journal of Yeungnam Medical Science
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• v.31 no.2
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• pp.131-134
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• 2014

Familial isolated primary hyperparathyroidism(FIPH) is associated with multiple endocrine neoplasia type 1 (MEN1) syndrome, primary hyperparathyroidism accompanied by jaw-tumor syndrome, and familial hypocalciuric hypercalcemia. FIPH may be an early stage of MEN1 or an allelic variant of MEN1. Thymic carcinoid tumor is a rare tumor in MEN1 syndrome. Here, the authors report the case of a 40-year-old man diagnosed with recurrent thymic carcinoid tumor and FIPH. Both the patient and his elder sister had been previously diagnosed to have FIPH with a novel frameshift mutation in the MEN1 gene. Initially, the patient underwent thymectomy because of an incidental finding of a mediastinal mass in his chest X-ray, and had remained asymptomatic over the following 4 years. Pancreas computed tomography conducted to evaluate MEN1 syndrome revealed anterior and middle mediastinal masses, and resultantly, massive mass excision was performed. Histological findings disclosed atypical carcinoids with infiltrative margins. In view of the thymic carcinoid tumor relapse that occurred in this patient, the authors recommend that regular pancreas and pituitary imaging studies be conducted for FIPH associated with a MEN1 gene mutation.

• Nuclear Medicine and Molecular Imaging
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• v.41 no.3
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• pp.255-257
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• 2007

A 59-year-old man with thymic carcinoma underwent Tc-99m MIBI myocardial SPECT, and Tc-99m MIBI uptake in the mass was unexpectedly found in a planar image. SPECT images of the thorax showed an increased uptake area with central photon deficiency (a ring-like appearance), which reflected central tumor irreversible ischemia or progressing necrosis with peripheral viable tumor tissue.

• Archives of Pharmacal Research
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• v.23 no.3
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• pp.252-256
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• 2000

A thymic stromal cell line, TFGD, was established from a thymic tumor mass developed spontaneously in p53 knock out mouse, and was found to produce cytokines that could induce bone marrow hematopoietic stem cells (HSCs) to differentiate into macrophages. The cytokines produced by the TFGD line were assessed by immunoassays. High level of macrophage-colony stimulating factor (M-CSF) and interleukin (IL)-6 was detected in the TFGD-culture supernatant, whereas granulocyte/macrophage-colony stimulating factor (GM-CSF), IL-3, IL-4, IL-5, IL-13, or interferon (IFN)-$\gamma$ was undetectable. Blocking experiments showed that anti-M-CSF monoclonal antibody could neutralize the differentiation-inducing activity shown by the TFGD-culture supernatant. Dot blot analysis of the total RNA isolated from the cultured fetal thymic stromal cells showed that M-CSF transcripts were expressed in the normal thymus. These observations, together with the earlier finding that M-CSF plus IL-6 is the optimal combination of cytokines for the induction of macrophage differentiation from HSCs in vitro, may indicate that thymic macrophages could be generated within the thymus by cytokines involving M-CSF.

• The Korean Journal of Cytopathology
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• v.2 no.2
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• pp.142-147
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• 1991

Diagnosis of a thymic carcinoid was made on transthoracic fine needle aspiration in a 36-year old woman who had an anterior mediastinal mass on chest X-ray and CT scan. The aspiration smears showed numerous anastomosing ribbons and cords of small round tumor cells. The tumor cells had slightly eccentric nuclei and some granular cytoplasm. The small and uniform nuclei of the tumor cells had finely granular chromatin and thin nuclear membrane. The cytologic diagnosis of a carcinoid was confirmed on histopathologic, immunohistochemical, and electromicroscopic examination of surgical specimen.

• YAKHAK HOEJI
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• v.59 no.4
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• pp.164-169
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• 2015

In the present study, we determined the effect of $18{\beta}$-glycyrrhetinic acid ($18{\beta}$-GA) in the mice model bearing xenografts of HT-29 human colon cancer cell line. Data from the cytotoxicity assay displayed that $18{\beta}$-GA induced cell death in HT-29. The cytotoxicity was enhanced as the $18{\beta}$-GA treatment was prolonged. In case of 72 hrs treatment, $LD_{50}$ of $18{\beta}$-GA was approximately $90{\mu}M$, and the efficacy at $100{\mu}M$ of $18{\beta}$-GA appeared to be equivalent to that of doxorubicin at $1{\mu}M$. Based on the in vitro data, we tested the anti-tumor effect of $18{\beta}$-GA in thymic mice (Balb/c strain). Xenograft tumors were generated by subcutaneous injection of HT-29 ($3{\times}10^6cells/mouse$) to mice and the mice were treated intraperitoneally with $18{\beta}$-GA ($50{\mu}g/time/mouse$) every other day for 4 times. The tumor volumes were measured for a period of 14 days. Data displayed that the $18{\beta}$-GA treatment reduced the tumor volumes (P < 0.05) as compared to control mice. However, this activity was demolished when athymic mice (Balb/c nu/nu) were used instead of thymic mice. This observation appeared that T lymphocyte played an important role in the anti-tumor activity. In conclusion, our results indicate that $18{\beta}$-GA has anti-tumor activity in HT-29 tumor-bearing mice, which may be associated with T cells.

• Tuberculosis and Respiratory Diseases
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• v.46 no.5
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• pp.718-722
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• 1999

Thymoma is the most common tumor in the compartment of anterior mediastinum. The malignant thymoma is classified into invasive thymoma(category I) and thymic carcinoma(category II). Recently, well-differentiated thymic carcinoma is a proposed category 1.5 used to describe a subset of thymic epithelial tumors, allowing for the existence of intermediate form based on the clinical features and the histological characteristics. Thymic cyst is a congenital or a acquired disorder. Congenital thymic cyst may develop due to failure of the thymopharyngeal duct to obliterate and acquired thymic cyst develops from inflammation(multilocular thymic cyst), or neoplasm(cystic thymoma). Cystic degeneration in thymoma is a relatively frequent but focal event. In rare cases, the process proceeds to the extent that most or all of the lesion becomes cystic. Until now, well-differentiated thymic carcinoma with extensive cystic degeneration has not been reported in our country. We experienced a case of 14 year-old female patient showing extensive cystic degeneration in well-differentiated thymic carcinoma. And so we report it with review of the articles related.