Mediastinum (Hong Kong, China)最新文献

Background and objective: Thymic epithelial tumors (TETs), including thymomas and thymic cancers, are relatively rare malignancies originating from the thymus. Although complete surgical resection is the cornerstone of treatment for these tumors, the optimal management strategy for locally advanced cases remains uncertain. Neoadjuvant therapies, with their potential to improve the likelihood of complete resection, are promising, particularly in marginally operable cases. However, the current evidence supporting this approach is lacking. This review of the existing literature on the efficacy of induction therapy followed by surgical resection for stage III or IV locally advanced TETs aimed to provide an up-to-date perspective and highlighting directions for future clinical research.

Methods: PubMed was searched using the keywords "surgery," "survival", "thymoma", "thymic cancer", and "induction therapy". Relevant articles including case series, retrospective studies, prospective studies, and review articles were reviewed and selected for this comprehensive narrative review.

Key content and findings: This review included primarily revealed retrospective studies and a limited number of prospective phase II trials on induction therapy followed by surgery for stage III or IV locally advanced TETs. No randomized phase III studies were identified, indicating that a comprehensive evaluation of the benefits of induction therapy on overall survival (OS) has not yet been conducted. Induction therapies for both invasive thymoma and thymic cancer included chemotherapy, radiotherapy, and chemoradiotherapy, with anthracycline-based combination chemotherapies being the primary option. For exclusively invasive thymomas, the median rate of complete surgical resection and the 5-year OS rate were reported as 76% and 85%, respectively. Literature focusing on induction therapy for TETs, which includes both thymoma and thymic cancers, indicates that the rates of complete resection and 5-year OS are 76% and 70%, respectively.

Conclusions: Our narrative review of retrospective and prospective studies highlighted promising long-term OS rates in patients with advanced TETs who underwent induction therapy followed by surgical resection. These findings support this multimodal treatment strategy in selected patients with stage III and IV TETs.

The mediastinal vasculature can be affected by various etiologies in cancer patients. Both direct and indirect sequela of cancer may result in life-threatening clinical presentations. Tumor growth may cause vessel narrowing and decreased blood flow from either extrinsic mass effect, invasion into the vascular wall, or tumor thrombus within the lumen. In addition, cancer patients are predisposed to indirect sequela to the mediastinal vasculature from an increased risk of benign thromboembolic events, tumor thrombus, or iatrogenic complications during cancer treatments. Benign thrombus may result in partial or complete occlusion of the superior vena cava (SVC) or pulmonary artery. Vascular damage such as pseudoaneurysm or stricture may result from iatrogenic complications from radiation therapy, surgery, or other interventions. The clinical presentation of the vascular compromise is dictated by the vascular anatomical structure that is affected and the type of injury. In the appropriate clinical scenario, endovascular treatments may be pursued. These minimally invasive procedures include balloon venoplasty and angioplasty, stent placement, catheter-directed thrombolysis, embolectomy, and embolization. This review discusses the most common endovascular interventions for vascular compromise based on the great vessel affected: the SVC, pulmonary artery, pulmonary vein, bronchial arteries, or the aorta and supra-aortic arteries. Indications for treatment are discussed, with particular attention to disease etiology and clinical presentation.

Background and objective: Thymic epithelial tumors (TETs), including thymomas and thymic carcinomas, are rare mediastinal tumors. Surgical resection is the treatment strategy for resectable TETs, and postoperative radiotherapy (PORT) is administered to improve local control in patients with a high risk of recurrence. The rarity of TETs has led to a lack of randomized controlled trials, and the current indications for PORT rely largely on retrospective studies. This review analyzes the literature on TETs, highlighting PORT, to guide current research and future investigations.

Methods: Studies that focused on TETs, addressed topics on PORT, and had English abstracts accessible online were eligible for inclusion in our review. We excluded case reports or review articles, articles written in languages other than English, articles published >30 years ago, and articles concerning thymic neuroendocrine tumors.

Key content and findings: Masaoka or Masaoka-Koga staging, World Health Organization (WHO) histological subtype, and resection status indicate PORT in resected TETs. Current literature suggests that PORT does not improve overall survival in stage I-IIA TETs, with inconsistent results for stage IIB-III TETs. Patients with a higher risk, such as carcinomas or WHO type B, might benefit from PORT if they do not develop distant metastasis. Determining which patients will benefit most from PORT requires further investigation. For recurrent TETs, the significance of applying PORT is unclear because available data are limited. Given the long-term survival of TETs, late toxicities, including radiation pneumonitis, radiation-induced cardiotoxicities, and secondary malignancies, must be addressed. Proton beam radiotherapy might reduce toxicities by sparing organs at risk compared to conventional photon beam radiotherapy. The use of high-precision radiation therapy, along with emerging immunotherapy, targeted therapy, and minimally invasive surgery, could improve TET outcomes.

Conclusions: This review consolidates the literature on PORT for TETs, factoring in the Masaoka-Koga staging, WHO histological subtypes, and resection status. Varying results regarding PORT efficacy have led to an undefined strategy for stage IIB-III TETs. Although advanced radiotherapy techniques promise to reduce radiation-induced toxicities, further research is needed to investigate the efficacy of PORT and combination therapy.

Locally invasive thymic neoplasms are challenging clinical scenarios and typically require a multidisciplinary approach. The involvement of major mediastinal veins such as the superior vena cava (SVC) used to be a contraindication to surgery, but with improved surgical technique and outcomes, this paradigm has shifted. In some situations, complex resections and reconstructions may be indicated and required to improve the long-term outcome of these patients. We report two of our cases along with a current review of literature. We also describe the preoperative workup, operative techniques, postoperative management, complications, and outcomes of patients with invasive thymic neoplasms that involve the mediastinal veins. Our first case describes a patient who was diagnosed with a thymoma extending from the diaphragm to the base of the neck that was also encasing major vascular structures including the SVC and left innominate vein. Our second case describes a patient who was also diagnosed with a large anterior mediastinal mass encasing the great veins and invading the chest wall. We describe the management of these patients and then delve deeper into operative techniques including SVC resection and reconstruction. We describe the types of conduits that can be used and complications to be mindful of when clamping the great veins, such as the SVC. Improvements in conduit materials and neoadjuvant and adjuvant therapies over the years have made it more feasible for patients with invasive thymic neoplasms to undergo surgery.

Background: Descending necrotizing mediastinitis (DNM) is an acute life-threatening infection that originates in the oropharyngeal region. It is an uncommon disease with a mortality rate of about 20-40%. This high mortality is mainly attributed to delays in diagnosis and treatment and poor drainage of the mediastinum. We highlight key points that may help reduce mortality.

Case description: We analyze a retrospective case series of seven patients diagnosed with DNM between March 2019 and July 2022 at Hospital de la Santa Creu i Sant Pau. The primary oropharyngeal infection was peritonsillar abscess in three cases and odontogenic abscess in four. All patients showed symptoms of severe cervical infection and symptoms suggestive of mediastinitis. A cervicothoracic computed tomography (CT) scan confirmed the presence of cervical and mediastinal collections and emphysema in all cases. All patients were simultaneously evaluated by the otorhinolaryngology and thoracic surgery teams. Broad-spectrum antibiotic therapy was instituted pending culture. All the patients underwent urgent surgery, consisting of cervicotomy to control the cervical focus and unilateral or bilateral video-assisted thoracoscopic debridement and drain of the pleural cavities and mediastinum. Regarding the outcomes, no patients died, one patient (14.2%) underwent transcervical mediastino-thoracoscopy drainage only. In six patients (85.8%) we performed a combined transcervical and transthoracic approach. Reoperation was required in 3 (43%) cases. The parameter that indicated a poor clinical evolution in these patients was an increase in C-reactive protein and the infection extension on the cervicothoracic CT scan. The follow-up was 30 days from last surgery; there were no losses.

Conclusions: Based on our experience, the key points that can help reduce the high mortality associated with DNM are a rapid multidisciplinary assessment and a combined surgical procedure, considering the minimally invasive approach as the first option to drain the pleural cavities and mediastinum.

Cardiovascular implantable electronic devices (CIEDs) such as pacemakers and implantable cardioverter defibrillators require the placement of a transvenous lead through the superior vena cava (SVC), which can be difficult if there is stenosis or obstruction of the SVC. Moreover, SVC syndrome may occur after the lead is inserted even if the SVC was intact before the implantation. Therefore, there is need of an appropriate strategy for handling stenosis or obstruction of SVC during lead placement. In addition, advances are being made in CIEDs that do not require transvenous leads, and thus CIEDs without a transvenous lead should be considered depending on the indications and urgency of the particular case. This manuscript is divided into (I) device therapy for patients with SVC obstruction and (II) therapeutic strategy for SVC obstruction after lead implantation. In patients with SVC syndrome, treatment of the SVC occlusion should be based on the individual pathophysiology, and depending on the indications and urgency of the case, treatment with CIEDs that do not require transvenous leads should be considered. Further data must be accumulated to clarify the long-term prognosis of device implantation after treatment of SVC occlusion. In addition, transvenous lead extraction is now widely used for device-related SVC obstruction, and this procedure also merits further accumulation of data.

Background and objective: Acute respiratory distress syndrome (ARDS) is a severe, life-threatening medical condition characterized by poor oxygenation due to non-compliant lungs secondary diffuse alveolar damage. Encouragingly, the incidence of ARDS has declined steadily recently, attributed mainly to implementation of keystone guidelines and continuous research efforts. Mechanical ventilation is the cornerstone of supportive care for ARDS patients. This review aims to consolidate the current knowledge on pneumothorax (PNX) and pneumomediastinum (PMD) and to enhance the understanding of the readers. The objectives are to (I) explore the etiology and risk factors of PNX and PMD, (II) discuss the various diagnostic modalities available, (III) evaluate management options, and (IV) recent advancements.

Methods: A search of the literature was conducted using PubMed, MEDLINE, and Google Scholar for relevant articles pertaining to PNX and PMD in ARDS population. The clinical presentation, diagnostic and management strategies of PNX, PMD, and ARDS were summarized, and all authors reviewed the selection and decide which studies to include.

Key content and findings: The adoption of lung-protective ventilation strategies, based on the review of literature from the recent years, shows that it has played a significant role in reducing the occurrence of barotrauma, such as PNX and PMD. However, PNX and PMD remains to be a challenging complication to manage. With a specific focus on PNX and PMD, this review provides valuable insights into effectively managing and understanding these critical complications among ARDS patients.

Conclusions: ARDS, with its evolving definition, continues to pose a life-threatening threat. Despite the widespread adoption of lung-protective ventilation strategies, PNX and PMD present persistent challenges in management. Further research is imperative to enhance the risk assessment of ARDS patients prone to developing PNX and PMD and to institute more effective prevention and treatment measures.

Lung cancers and mediastinal masses can invade the veins in the upper mediastinum and neck. It can be challenging to determine management options and the feasibility of resection particularly when tumors involve the major venous junctions. Furthermore, impaired flow in these veins can have devastating complications such as Paget-Schroetter syndrome, which describes a constellation of symptoms (arm swelling, cyanosis, pain) due to stenosis of the subclavian vein. This section will provide an overview of venous drainage of the brain, which can be divided into two major systems-superficial medullary venous system and deep medullary venous system. The anatomy and function of the great veins of the neck and upper mediastinum, including the internal jugular vein, subclavian vein, and brachiocephalic (i.e., innominate) vein will be described. Also discussed will be principles of ligation of the venous structures and the importance of keeping the venous junctions intact to facilitate and maximize the development of collateral flow. This section will also discuss ensuing complications when blood flow is impaired, such as development of upper extremity deep venous thrombosis and cerebral venous thrombosis (CVT). CVT can result in a stroke and is an umbrella term that refers to problems in cerebral venous outflow due to numerous etiologies.