-
Journal of Thoracic Oncology : Official... Oct 2010Thymomas are tumors of thymic epithelial cells. They associate more often than any other human tumors with various autoimmune diseases; myasthenia gravis is the... (Review)
Review
Thymomas are tumors of thymic epithelial cells. They associate more often than any other human tumors with various autoimmune diseases; myasthenia gravis is the commonest, occurring in 10-50% of thymoma patients, depending on the World Health Organization-defined histologic subtype. Most thymomas generate many polyclonal maturing T lymphocytes but in disorganized microenvironments Failure to induce self-tolerance may be a key factor leading to the export of potentially autoreactive CD4 progeny, thus predisposing to autoimmune diseases. Normally, the master Autoimmune Regulator promotes expression of peripheral tissue-restricted antigens such as insulin by medullary thymic epithelial cells and induction of tolerance to them. The failure of approximately 95% of thymomas to express autoimmune regulator is another feature potentially contributing to autoimmunity.
Topics: Autoimmune Diseases; Autoimmunity; Humans; Thymoma; Thymus Neoplasms; Transcription Factors; AIRE Protein
PubMed: 20859117
DOI: 10.1097/JTO.0b013e3181f1f63f -
Romanian Journal of Morphology and... 2010Thymomas are rare tumors of the thymic epithelium with a broad spectrum of morphological and clinical features. Despite a benign histological appearance, it can invade...
Thymomas are rare tumors of the thymic epithelium with a broad spectrum of morphological and clinical features. Despite a benign histological appearance, it can invade nearby structures or metastasize. The majority of patients are asymptomatic, but some may present with paraneoplastic syndromes such as myasthenia gravis, red cell aplasia, or hypogammaglobulinemia. Various staging systems of thymomas have been defined based on the degree of invasiveness. According to the WHO Classification, there are six histologic types of thymic epithelial tumors. The most important prognostic factor is the stage according to Masaoka's system. We report a case of invasive thymoma diagnosed incidentally in a patient with cardiovascular risk factors referred to the cardiologist with suspected thoracic aorta aneurism.
Topics: Humans; Lung; Middle Aged; Neoplasm Invasiveness; Thymoma; Thymus Neoplasms; Tomography, X-Ray Computed
PubMed: 20809041
DOI: No ID Found -
Journal of Clinical Pathology Dec 2006The diagnosis of thymic epithelial neoplasm has been a topic of controversy for many years. Reasons for this include the lack of predictive value associated with the... (Review)
Review
The diagnosis of thymic epithelial neoplasm has been a topic of controversy for many years. Reasons for this include the lack of predictive value associated with the morphology of these tumours and the multiplicity of classification schemes and terminologies proposed over the years. Recently, a new classification schema was introduced by the World Health Organization (WHO) in an attempt to standardise nomenclature and facilitate the diagnosis of primary thymic epithelial neoplasms. This schema, although not originally intended as a new histological classification, but rather as a means for translating equivalent terms from the various existing classifications, has represented a major step forward in this direction. However, problems still exist with the WHO schema, particularly with some of the criteria for the various histological subtypes as well as with issues of interobserver reproducibility. For this reason, we favour using a much more simplified approach to the morphological classification of thymic epithelial neoplasms. A personal approach to the morphological diagnosis of thymoma is described, with a brief explanation for the rationale for simplifying the existing diagnostic categories.
Topics: Diagnosis, Differential; Humans; Male; Middle Aged; Thymoma; Thymus Neoplasms; World Health Organization
PubMed: 16679354
DOI: 10.1136/jcp.2005.031138 -
International Journal of Molecular... Jan 2024Thymic epithelial tumors (TETs) are characterized by their extreme rarity and variable clinical presentation, with the inadequacy of the use of histological... (Review)
Review
Thymic epithelial tumors (TETs) are characterized by their extreme rarity and variable clinical presentation, with the inadequacy of the use of histological classification alone to distinguish biologically indolent from aggressive cases. The utilization of Next Generation Sequencing (NGS) to unravel the intricate genetic landscape of TETs could offer us a comprehensive understanding that is crucial for precise diagnoses, prognoses, and potential therapeutic strategies. Despite the low tumor mutational burden of TETS, NGS allows for exploration of specific genetic signatures contributing to TET onset and progression. Thymomas exhibit a limited mutational load, with prevalent and mutations. On the other hand, thymic carcinomas (TCs) exhibit an elevated mutational burden, marked by frequent mutations in and genes associated with epigenetic regulation. Moreover, signaling pathway analyses highlight dysregulation in crucial cellular functions and pathways. Targeted therapies, and ongoing clinical trials show promising results, addressing challenges rooted in the scarcity of actionable mutations and limited genomic understanding. International collaborations and data-sharing initiatives are crucial for breakthroughs in TETs research.
Topics: Humans; Epigenesis, Genetic; Thymus Neoplasms; Thymoma; Neoplasms, Glandular and Epithelial
PubMed: 38338833
DOI: 10.3390/ijms25031554 -
Journal of Thoracic Oncology : Official... Oct 2010The use of targeted therapies for the treatment of thymic malignancies is documented in the literature. However, only a few drugs have undergone evaluation in phase II... (Review)
Review
The use of targeted therapies for the treatment of thymic malignancies is documented in the literature. However, only a few drugs have undergone evaluation in phase II trials. Most of the evidence for the benefit of biologic therapies for thymic malignancies is in the form of case reports and small case series. No major activity has been observed with any agent so far, likely due to the lack of selection of patients for targeted therapies and the small numbers studied. A better understanding of the biology of these tumors will be essential in furthering the field.
Topics: Antineoplastic Agents; Clinical Trials as Topic; Humans; Neoplasm Proteins; Prognosis; Thymoma; Thymus Neoplasms
PubMed: 20859134
DOI: 10.1097/JTO.0b013e3181f21114 -
Journal of Thoracic Oncology : Official... Oct 2010Thymic malignancies are rare intrathoracic tumors that may be aggressive and difficult to treat in advanced stage. Over the past years, significant efforts have been... (Review)
Review
INTRODUCTION
Thymic malignancies are rare intrathoracic tumors that may be aggressive and difficult to treat in advanced stage. Over the past years, significant efforts have been conducted to dissect the molecular pathways involved in the carcinogenesis of these tumors. Insights have been made following anecdotal clinical responses to targeted therapies, and large-scale genomic analyses have been conducted.
METHODS
Review of the literature, 1990-2010.
RESULTS
The Epidermal Growth Factor Receptor (EGFR) is frequently overexpressed in thymomas and thymic carcinomas, but EGFR mutations are exceptional, and this does not support the use of EGFR tyrosine kinase inhibitors. On the contrary, single observations of responses create a basis for further evaluation of cetuximab in thymomas. KIT-mutant thymic carcinomas represent a small molecular subset of thymic tumors. The clinical relevance of KIT mutations is more limited in thymic carcinoma than in GIST as KIT mutations are far less frequent (7% of thymic carcinomas) and are not correlated with KIT expression; furthermore, KIT mutants are not uniformly sensitive to imatinib. Beyond EGFR and KIT signaling pathways, other molecular alterations with potential prognostic or predictive relevance are emerging in thymic malignancies.
CONCLUSIONS
Given the rarity of these tumors, translation of preclinical findings to the clinic may be quick and represents one of the most promising therapeutic approaches for advanced-stage thymic malignancies.
Topics: Antineoplastic Agents; ErbB Receptors; Humans; Proto-Oncogene Proteins c-kit; Signal Transduction; Thymoma; Thymus Neoplasms
PubMed: 20859122
DOI: 10.1097/JTO.0b013e3181f209b9 -
Virchows Archiv : An International... Nov 2015The mediastinum is an anatomically defined space in which organs and major blood vessels reside with surrounding soft tissue elements. The thymus is an important organ... (Review)
Review
The mediastinum is an anatomically defined space in which organs and major blood vessels reside with surrounding soft tissue elements. The thymus is an important organ in the mediastinum, and many of the masses encountered in the mediastinum are related to this organ. Most neoplasms diagnosed in the mediastinum are epithelial tumours (thymomas and thymic carcinomas), lymphomas or germ cell tumours. In contrast, soft tissue tumours of the mediastinum are rare. In 1963, Pachter and Lattes systematically reviewed soft tissue pathology of the mediastinum, covering the hitherto described [2, 226, 227] In this review, based on the 2013 WHO classification of soft tissue tumours and the 2015 WHO classification of tumours of the lung, pleura, thymus and heart, we provide an updated overview of mesenchymal tumours that may be encountered in the mediastinum.
Topics: Diagnosis, Differential; Humans; Mediastinum; Mesoderm; Neoplasm Grading; Thymoma; Thymus Neoplasms
PubMed: 26358059
DOI: 10.1007/s00428-015-1830-8 -
Open Veterinary Journal 2022The most common cranial mediastinal masses affecting dogs and cats include lymphoma and thymic epithelial tumors. In this report, a cat with a cranial mediastinal mass...
BACKGROUND
The most common cranial mediastinal masses affecting dogs and cats include lymphoma and thymic epithelial tumors. In this report, a cat with a cranial mediastinal mass was diagnosed with a thymic carcinoma subtype squamous cell carcinoma, which has rarely been reported in cats. Management of this subtype with a combination of surgery and chemotherapy has so far not been reported. This case report describes the treatment with surgical management followed by intracavitary carboplatin.
CASE DESCRIPTION
A 12-year-old male neutered domestic short hair cat was referred for lethargy, hyporexia, and weight loss, and was diagnosed with a cranial mediastinal mass radiographically. Initial cytology through fine needle aspirates was suggestive of carcinoma. Computed tomography was performed which did not show evidence of other primary tumor sources or metastases, and hence surgical resection was recommended. Intraoperative findings revealed local invasion of the surrounding tissues, including major vasculature and nerves, although histopathological assessment showed no local lymph node involvement. Intracavitary carboplatin chemotherapy was administered 2 weeks postsurgery. The patient was humanely euthanized 4 weeks postsurgery due to evidence of local recurrence causing significant respiratory compromise.
CONCLUSION
A combination of surgical excision as well as intracavitary carboplatin does not seem to be effective for the treatment of this thymic carcinoma subtype, with evidence of early recurrence and return of clinical signs.
Topics: Male; Cats; Animals; Dogs; Thymoma; Carboplatin; Cat Diseases; Dog Diseases; Thymus Neoplasms; Carcinoma, Squamous Cell
PubMed: 36589403
DOI: 10.5455/OVJ.2022.v12.i5.5 -
European Radiology Jul 2016To evaluate the usefulness of diffusion-weighted magnetic resonance for distinguishing thymomas according to WHO and Masaoka-Koga classifications and in predicting...
Diffusion-weighted magnetic resonance imaging of thymoma: ability of the Apparent Diffusion Coefficient in predicting the World Health Organization (WHO) classification and the Masaoka-Koga staging system and its prognostic significance on disease-free survival.
OBJECTIVES
To evaluate the usefulness of diffusion-weighted magnetic resonance for distinguishing thymomas according to WHO and Masaoka-Koga classifications and in predicting disease-free survival (DFS) by using the apparent diffusion coefficient (ADC).
METHODS
Forty-one patients were grouped based on WHO (low-risk vs. high-risk) and Masaoka-Koga (early vs. advanced) classifications. For prognosis, seven patients with recurrence at follow-up were grouped separately from healthy subjects. Differences on ADC levels between groups were tested using Student-t testing. Logistic regression models and areas under the ROC curve (AUROC) were estimated.
RESULTS
Mean ADC values were different between groups of WHO (low-risk = 1.58 ± 0.20 × 10(-3)mm(2)/sec; high-risk = 1.21 ± 0.23 × 10(-3)mm(2)/sec; p < 0.0001) and Masaoka-Koga (early = 1.43 ± 0.26 × 10(-3)mm(2)/sec; advanced = 1.31 ± 0.31 × 10(-3)mm(2)/sec; p = 0.016) classifications. Mean ADC of type-B3 (1.05 ± 0.17 × 10(-3)mm(2)/sec) was lower than type-B2 (1.32 ± 0.20 × 10(-3)mm(2)/sec; p = 0.023). AUROC in discriminating groups was 0.864 for WHO classification (cut-point = 1.309 × 10(-3)mm(2)/sec; accuracy = 78.1 %) and 0.730 for Masaoka-Koga classification (cut-point = 1.243 × 10(-3)mm(2)/sec; accuracy = 73.2 %). Logistic regression models and two-way ANOVA were significant for WHO classification (odds ratio[OR] = 0.93, p = 0.007; p < 0.001), but not for Masaoka-Koga classification (OR = 0.98, p = 0.31; p = 0.38). ADC levels were significantly associated with DFS recurrence rate being higher for patients with ADC ≤ 1.299 × 10(-3)mm(2)/sec (p = 0.001; AUROC, 0.834; accuracy = 78.0 %).
CONCLUSIONS
ADC helps to differentiate high-risk from low-risk thymomas and discriminates the more aggressive type-B3. Primary tumour ADC is a prognostic indicator of recurrence.
KEY POINTS
• DW-MRI is useful in characterizing thymomas and in predicting disease-free survival. • ADC can differentiate low-risk from high-risk thymomas based on different histological composition • The cutoff-ADC-value of 1.309 × 10 (-3) mm (2) /sec is proposed as optimal cut-point for this differentiation • The ADC ability in predicting Masaoka-Koga stage is uncertain and needs further validations • ADC has prognostic value on disease-free survival and helps in stratification of risk.
Topics: Adult; Aged; Aged, 80 and over; Area Under Curve; Diffusion Magnetic Resonance Imaging; Disease-Free Survival; Female; Humans; Male; Middle Aged; Neoplasm Staging; Prognosis; Retrospective Studies; Thymoma; Thymus Neoplasms; World Health Organization
PubMed: 26427698
DOI: 10.1007/s00330-015-4031-6 -
Journal of Veterinary Diagnostic... Nov 2019A Rock Alpine doe () was presented to the Colorado State University Veterinary Teaching Hospital because of scaling and ulceration over the withers, coronary bands, and... (Review)
Review
A Rock Alpine doe () was presented to the Colorado State University Veterinary Teaching Hospital because of scaling and ulceration over the withers, coronary bands, and dewclaws. The doe was euthanized because of poor prognosis associated with a radiographically identified cranial mediastinal mass, increased respiratory effort, and discomfort. Autopsy revealed a cranial mediastinal mass, and scaling-to-ulcerative lesions affecting the dorsum, ventrum, pinna, neck, teats, coronary bands, and dewclaws. Histologically, the mediastinal mass was an epithelial neoplasm with admixed non-neoplastic T lymphocytes, consistent with a lymphoepithelial (mixed) thymoma. Sections of affected skin were characterized by hyperkeratotic cell-rich interface dermatitis with transepidermal and follicular apoptosis. Thymoma-associated exfoliative dermatitis has been recognized in cats and a rabbit, but has not been reported previously in a goat, to our knowledge. Given that thymomas are not uncommon in goats, thymoma-associated exfoliative dermatitis should be considered a clinical differential in goats with dermatologic disease.
Topics: Animals; Colorado; Dermatitis, Exfoliative; Fatal Outcome; Female; Goat Diseases; Goats; Skin; Thymoma; Thymus Neoplasms
PubMed: 31650897
DOI: 10.1177/1040638719884957