Mediastinum (Hong Kong, China)最新文献

Background and objective: Thymic epithelial tumors, including thymomas and thymic carcinomas, represent the most common mediastinal tumors and account for up to 50% of all anterior mediastinal tumors. For early stages of these thymic tumors, complete resection of the entire thymus is the recommended treatment. The transition from open surgery to video-assisted thoracoscopic surgery (VATS) and recently to robotic-assisted thoracic surgery (RATS) has fundamentally altered the treatment of thymic tumors. While RATS has been widely implemented due to its many advantages including good visualization with magnification and three-dimensional vision, improved maneuverability and precise instrument control, different techniques have been described. This narrative review focuses on the main approaches and outcomes of RATS thymectomy. It compares the technical, perioperative and clinical outcomes of RATS thymectomy, in particular, with VATS and open thymectomy.

Methods: A non-systematic review for full text studies written in the English language was conducted using the PubMed search engine and literature was summarized.

Key content and findings: We present an overview of robotic-assisted resection for thymomas and review the main approaches and outcomes of RATS thymectomy. Critical points of the RATS approach, including surgical specifics and pitfalls, are presented. Technical advantages and disadvantages of each technique are discussed. The perioperative and clinical outcomes of RATS thymectomy are compared, where possible, to those for VATS and open thymectomy. Currently, retrospective analyses demonstrate comparable or even more favorable outcomes following a RATS approach in comparison to VATS and open approaches in terms of operating time, conversion rates, intraoperative complications, completeness of resection and mortality. Certain analyses also report better outcomes for patients undergoing RATS thymectomy in terms of blood loss, postoperative complications, duration of pleural drainage and length of hospital stay compared to VATS and open thymectomy.

Conclusions: Overall, RATS has shown promising results and could become the preferred technique for resection of thymic tumors. It shows good outcomes compared to VATS and open thymectomy in the current literature. However, especially for extended tumors with the need for extended resection and reconstruction, open thymectomy remains a valuable approach.

Background and objective: Thymic epithelial tumors (TETs) are the most common neoplasm of the prevascular mediastinal compartment and are characterized by their rarity and variable clinical presentation. The present study aimed to explore the current management of patients with TET with a special focus on immunotherapy for advanced disease.

Methods: Relevant studies published between 1981 and 2024 were searched in PubMed using search terms "Thymoma", "Thymic cancer", "Myasthenia gravis", "Radiation therapy", "Surgery", and "Immunotherapy".

Key content and findings: The International Thymic Malignancy Interest Group and the International Association for the Study of Lung Cancer established the tumor-node-metastasis (TNM) staging system for TET based on an overall survival (OS) analysis of a retrospective international database. While complete surgical resection is the mainstay for resectable TET, there are currently no clear guidelines on systemic treatments for advanced TET because of the complexity, rarity, and heterogeneity of this disease and the lack of in vivo and in vitro models. With the development of immunotherapy, the application of the anti-programmed cell death-1 (anti-PD-1) antibody is expanding and includes TET. Clinical trials on immune checkpoint inhibitors (ICIs) are ongoing, and the acceptable clinical efficacy of the anti-PD-1 antibody for TET has been reported. On the other hand, there have been reports of a heightened frequency of severe immune-related adverse events (irAEs) in TET.

Conclusions: ICIs have the potential for patients with TET. The benefit-toxicity ratio of ICI treatment needs to be carefully evaluated for those patients.

Background and objective: There are several benign processes that affect the mediastinum with considerable morbidity that may range from reactive entities to neoplastic disorders. This review article will focus on non-neoplastic benign mediastinal diseases which include large vessel vasculitis such as Takayasu and giant cell arteritis, mediastinal granulomas, fibrosing mediastinitis and mediastinal infections. These diseases can cause significant morbidity and mortality; therefore, we aim to familiarize readers with the pathophysiology, epidemiology and diagnosis of these mediastinal diseases and provide an update on the treatment options available.

Methods: We searched various databases such as PubMed and Google Scholar from August 2023 until January 2024 for the various benign mediastinal disorders we wanted to discuss. Relevant articles that were written in English were shortlisted and used to help write this narrative review.

Key content and findings: We will briefly discuss the anatomy of the mediastinum along with some of the more common benign mediastinal disorders. We will discuss epidemiology, etiology, clinical features, and treatment. Relevant laboratory, and imaging findings important to make the diagnosis will be included as well.

Conclusions: Prompt diagnosis of these diseases is of the utmost importance as delay in care may be associated with increased mortality. Our article aims to provide an up-to-date review and summarize the current literature regarding these diseases.

Background: Emphysematous esophagitis is a very rare disease and there are only a few previous reports in the literature. Previously reported cases have resulted in emphysematous esophagitis following anterior cervical procedures or ingestion of hydrogen peroxide (HP). In this report, we describe a case in which a patient with emphysematous esophagitis accompanied by gastritis without the above predisposing factors was treated with conservative treatment.

Case description: A 65-year-old woman was admitted to Inje University Sanggye Paik Hospital with general weakness, abdominal discomfort, nausea and chest discomfort. On chest and abdominal radiographs, there were abnormal air density in upper mediastinum and abdomen. Chest and abdomen computed tomography (CT) revealed mural air at entire esophagus and stomach. The patient managed with proton pump inhibitor (PPI), broad spectrum antibiotic therapy, and total parenteral nutrition (TPN).

Conclusions: Emphysematous gastritis occurs mainly along with emphysematous gastritis, with a mortality rate of up to 62%. It is mainly known to be caused by infection of the esophageal wall by gas forming bacteria, but there are also cases where there is no ingestion or exact cause. There is still controversy about treatment methods due to the high death rate, but if detected early like the reported patient, a good outcome can be expected with conservative treatment alone.

Background: Thymic cysts can be classified as congenital or acquired. Most thymic cysts do not change in size over a short period of time. Although very rare, thymic cyst rupture is associated with serious complications, such as mediastinal hemorrhage and hemothorax. We experienced a case of partial rupture of a secondary thymic cyst, in an asymptomatic patient.

Case description: A 60-year-old woman visited Inje University Sanggye Paik Hospital with left hilar bulging detected on routine chest radiograph. A chest computed tomography (CT) scan revealed a 6 cm well-defined cystic mass with partial septation in the prevascular mediastinum. Thus, secondary thymic cyst was suggested. On the follow-up chest CT scan taken 3 months later, the size of the thymic cyst decreased, while the solid portion increased slightly, suggesting the potential presence of malignancy. Consequently, surgery was conducted. Adhesion to the lung and aorta was observed, but they were relatively well separated. The pathological findings revealed a partially ruptured thymic cyst with fat necrosis and multifocal granulomas.

Conclusions: There are controversies in the treatment of thymic cysts. Some clinicians prefer strict medical supervision to avoid unnecessary surgery, while others advocate immediate excision to avoid complication. However, if any changes are observed during the follow-up of the thymic cyst, it may indicate malignant transformation or rupture, necessitating prompt surgical excision.

This review article comprehensively examines the diagnostic approach to thymic epithelial tumors (TETs) and other mediastinal masses, focusing on imaging modalities and differential diagnosis. Beginning with a discussion on traditional and contemporary classification systems for mediastinal tumors, including the Japanese Association for Research on the Thymus (JART) and International Thymic Interest Group (ITMIG) classifications, it highlights the shift towards computed tomography (CT)-based categorizations. Emphasis is placed on the importance of distinguishing between solid and cystic lesions in the anterior mediastinum, with detailed insights into imaging characteristics and histological features of various TET subtypes such as thymomas, thymic carcinomas, and thymic neuroendocrine tumors (NETs). The review also elucidates common differential diagnoses, including lymphomas and germ cell tumors, providing guidance on key imaging findings and considerations for accurate diagnosis. Furthermore, it underscores the significance of patient background and blood tests in differential diagnosis, discussing age-related prevalence patterns and tumor marker assessment. After addressing the diagnostic challenges posed by thymic cysts offering insights into their radiological features, management considerations, and potential complications, this review extends to other rare mediastinal lesions highlighting the need for a comprehensive evaluation for accurate identification and management of these tumors. Finally, as illustrative examples, we present six cases highlighting various aspects of anterior mediastinal tumors, including TET. These cases provide valuable insights into the diagnostic challenges, imaging characteristics, and management considerations encountered in clinical practice. The cases presented herein do not all illustrate typical images, courses, and diagnoses. However, they each contain significant implications. Thus, we present them with the belief that they will aid in understanding the intricate nuances of image diagnosis in actual clinical practice.

Background and objective: Thymic carcinoma is an exceptionally rare cancer, with an annual incidence of just 0.15-0.29 per 100,000 people. Owing to its rarity, only few proven treatments have been developed. Understanding its genetic profile is crucial for the development of targeted therapies. However, limited studies have exclusively examined thymic carcinoma mutations, with most investigation combining thymomas and thymic carcinomas. This paper reviews findings from genetic studies focusing on thymic carcinoma alone and compares them to those of thymoma.

Methods: We conducted a PubMed search for relevant English studies on thymic carcinoma genomics. Then, key papers utilizing target sequencing or whole-exome sequencing were analyzed.

Key content and findings: The most frequently mutated genes were TP53, CDKN2A, CDKN2B, CYLD, KIT, TET2, SETD2, BAP1, and ASXL1. TP53 and CDKN2A are correlated with poor prognosis. CYLD, which regulates signaling related with proliferation and interacts with AIRE expression and T cell development, might predict the immunotherapy response. KIT mutations might enable targeted therapy. TET2, SETD2, BAP1, and ASXL1 regulate epigenetics, suggesting disruption of these mechanisms. Higher tumor mutational burden (TMB) and 16q loss distinguish thymic carcinoma from thymoma. Although some copy number aberrations are shared, thymic carcinoma exhibits a mutational profile distinct from that of thymoma.

Conclusions: Thymic carcinoma demonstrates a unique genomic landscape, suggesting a molecular pathogenesis distinct from that of thymoma. Our findings revealed prognostic biomarkers such as TP53/CDKN2A and potential therapeutic targets such as KIT. Because thymic carcinoma is extremely rare, sharing molecular profiling data could provide valuable insights into the molecular mechanisms driving the development of these tumors.

Thymic epithelial tumors (TETs), encompassing thymoma and thymic carcinoma, represent a rare and heterogeneous group of thoracic malignancies with varying prognoses and treatment strategies. Surgical resection is the cornerstone of therapy for localized stages, but the management of locally advanced or unresectable TETs often involves induction therapy, including chemotherapy and/or radiation therapy, as a neoadjuvant approach aimed at downstaging the tumor to facilitate subsequent resection. This review synthesizes current knowledge on the re-evaluation process and operative indications following induction therapy for TETs, highlighting the pivotal role of accurate assessment in guiding surgical decisions and optimizing patient outcomes. Induction therapy's efficacy is contingent upon precise re-evaluation methods to accurately gauge treatment response and assess resectability post-therapy. This review discusses the various modalities employed in re-evaluation, including computed tomography (CT), magnetic resonance imaging (MRI), positron emission tomography-CT (PET-CT), and the significance of tumor markers, underlining their strengths and limitations. The adoption of modified RECIST criteria for TETs by the International Thymic Malignancy Interest Group (ITMIG) underscores the necessity for standardized assessment guidelines to ensure consistency and reliability across studies and clinical practices. Furthermore, we explore the implications of induction therapy on surgical decision-making, emphasizing the criteria for determining the suitability of patients for surgical intervention post-therapy. The review addresses the challenges and future perspectives associated with the re-evaluation process, including the potential for advanced imaging techniques and the integration of molecular and genetic markers to enhance the precision of treatment response assessment. In conclusion, the re-evaluation of TETs post-induction therapy is a complex but critical component of the multidisciplinary management approach for these patients. Standardizing re-evaluation methodologies and incorporating novel diagnostic tools could significantly improve the prognostication and treatment stratification, ultimately enhancing the therapeutic outcomes for patients with advanced TETs.

Background and objective: Thymic epithelial tumors (TETs) are rare and originate from the thymus. Thymomas and thymic carcinomas are the most common types of TETs. Of the two, thymomas tend to have a better prognosis and are typically localized, while thymic carcinomas have a worse prognosis and are more likely to spread. The Masaoka-Koga staging system is commonly used to determine the stage of TETs. Complete resection is the preferred treatment option, but treating locally advanced TETs can be challenging due to the invasion of surrounding structures. In such cases, induction therapy is administered to downstage the tumors and enable complete resection. We conducted this narrative review to evaluate the current progress in induction treatment for locally advanced TETs.

Methods: The literature search was performed using PubMed and Web of Science in June 2023. Prospective and retrospective published trials, systemic and narrative reviews, and meta-analyses were included.

Key content and findings: Induction chemotherapy is often used as a preoperative treatment for advanced TETs. Platinum and anthracycline-based chemotherapy regimens are commonly used for treating thymoma (response rate, 37-100%), and complete resection is highly common. Treatment with cisplatin and etoposide, carboplatin and paclitaxel, docetaxel and cisplatin have also demonstrated effectiveness, particularly in patients with thymic carcinoma or thymoma who cannot tolerate anthracycline regimens. The emergence of immunotherapy and targeted therapies may provide additional options for the treatment of TETs. Induction radiotherapy, as the sole treatment for TETs, is not widely practiced due to concerns about potential damage to surrounding tissues. However, combining modern radiation techniques with surgery has shown promising results in selected patients. Induction chemoradiotherapy, which combines chemotherapy and radiation, is an emerging approach for treating TETs. Despite the lack of randomized trials comparing chemotherapy with chemoradiotherapy, concurrent chemoradiation with radiation doses of 40-50 Gy is often considered the optimal induction therapy for thymic carcinoma patients or in more advanced special situations, such as great vessel invasion.

Conclusions: Overall, the optimal treatment for locally advanced TETs remains controversial. Induction therapy, including chemotherapy, radiotherapy, or chemoradiotherapy, is administered to downstage tumors and improve resectability. The choice of treatment depends on individual factors such as tumor stage, histology, and overall patient condition. However, further research and well-designed studies are needed to determine the most effective treatment strategies for locally advanced TETs.