Mediastinum (Hong Kong, China)最新文献

Treatment decision-making of thymic epithelial tumors (TETs) after surgery is based on the pathological stage. Currently, most institutions use both the Masaoka-Koga system and the 8th edition of the tumor, node, metastasis (TNM) classification. Because these two systems separate each stage according to the same concept, namely, the "levels" of tumor extension, precise pathological evaluation of the presence or absence of tumor invasion into stage-defining structures is necessary. This review provides representative pathological snapshots of tumors invading neighboring structures to provide references that might be helpful to readers; the snapshots will cover features that correspond to those of "locally advanced TETs", the topic of this series. Tumor subtype, whether thymoma or thymic carcinoma, is another factor influencing treatment decisions. Accumulating evidence has indicated that most thymomas and thymic carcinomas have biologically distinct features. Representative results were achieved by a study conducted as part of The Cancer Genome Atlas (TCGA) project, and subsequent studies with the help of the TCGA data have further reported on these distinctive features. Here, we also introduce newly recognized features of TETs, mainly focusing on the difference between epithelial-rich thymomas and thymic squamous cell carcinoma. The new (9th) edition of the TNM classification will be launched in January 2024. Therefore, sharing current pathological features of TETs will help readers, not only in their daily practice but also in preparing for the upcoming classification system.

Background: Primary mediastinal liposarcoma is a rare malignancy of mesenchymal origin with local aggressive biological behavior which is often diagnosed as an incidental finding without any symptoms. Chemoresistance and low radiosensitivity of these tumors favors surgical resection as the only option for radical treatment. The potential need for extended resections of adjacent structures is not uncommon and could be challenging. Only a limited number of cases with successful vascular reconstruction for the treatment of mediastinal liposarcoma has been reported so far.

Case description: A 69-year-old female patient was admitted to our department with dry cough and a huge mediastinal mass for further investigation and treatment. Based on the results of preoperative examinations a mediastinal liposarcoma was suspected. The tumor was resected through median sternal incision with resection of the pericardium with subsequent mesh replacement and "en bloc" resection of the innominate vein with vascular graft reconstruction. The postoperative course was uneventful. Six months follow-up after surgery showed no signs of local recurrence or dissemination.

Conclusions: Extended resection and vascular reconstruction for the surgical treatment of primary mediastinal liposarcoma is often necessary to ensure adequate radicality and to reduce the risk of local recurrence. Therefore, these patients should be treated in high-volume centers with sufficient experience.

Background: Taste disorders in patients with thymoma accompanied by myasthenia gravis (MG) is rare.

Case description: The first case was a male in his 50s who underwent surgery for Masaoka stage III type B3 thymoma. He experienced a loss of taste before surgery, which showed no improvement after surgery. Due to a MG crisis 44 days after surgery, the patient underwent intensive treatment with mechanical ventilation, steroid pulse therapy, and intravenous immunoglobulin (IVIG) therapy. The patient recovered taste when he started oral food intake after the treatment for the MG crisis (about 3 months after surgery). Despite the recovery of taste after steroid pulse therapy and IVIG therapy, taste disorder gradually worsened about 1 year and 9 months after surgery, resulting in an almost complete loss of sweet taste 2 years after surgery. The second case was a male in his 60s who underwent surgery for Masaoka stage II type B1 thymoma. He experienced loss of taste before surgery, which showed no improvement after surgery. Five years and two months after surgery, the patient was diagnosed with a MG crisis and underwent steroid pulse therapy. Along with improvements in MG symptoms, taste disorders gradually improved. After 6 years and 10 months of surgery, the patient is still alive without MG symptoms (only pyridostigmine, 180 mg/body/day), taste disorder, and thymoma recurrence.

Conclusions: The autoimmune mechanism may contribute to taste disorders in patients with thymoma, which can be recovered by immunosuppressive treatment in our cases.

Malignant central airway obstruction (MCAO) impacts many patients with advanced primary lung cancers and metastatic disease to the thorax and may cause substantial symptoms and functional limitations in those affected. Making the diagnosis may be challenging as symptoms are often non-specific but identification is improved with a heightened level of suspicion and newer thoracic imaging modalities. Bronchoscopy plays a crucial role in the diagnosis and management of MCAO and therapeutic interventions may be lifesaving and result in palliation of symptoms. This may ultimately improve a patient's candidacy to receive additional systemic or local cancer therapies or potential tumor resection. After initial stabilization, it is important that patients with MCAO undergo prompt evaluation and treatment. Multiple bronchoscopic instruments are available for management depending on tumor characteristics, location of the obstruction, and viability of distal airways, and may be utilized in combination during therapeutic procedures. These modalities include dilation, endobronchial stent placement, thermal and non-thermal ablation, mechanical debulking, and novel endobronchial therapies. While these procedures are not without risk, there is ample evidence showing improvements in patient symptoms, quality of life, and survival following therapeutic bronchoscopy. This review article provides a general overview of the diagnosis and management of MCAO with a focus on bronchoscopic interventions.

Lymphomas are among the most common malignant tumors occurring in the anterior/prevascular mediastinum. Their diagnoses can be challenging in small biopsies, the current most common method of sampling of an anterior mediastinal mass. Because the initial clinical and/or imaging impression may not be that of lymphoma, these specimens may first be evaluated by cytopathologists, surgical pathologists, and thoracic pathologists rather than hematopathologists. Therefore, it is crucial for this group of pathologists to have a practical diagnostic approach to these neoplasms, know their common diagnostic pitfalls, and their main differential diagnoses. This is important because the diagnosis of lymphoma carries significant therapeutic implications (chemotherapy and/or radiotherapy and not surgical resection). Similarly, securing and properly triaging a sample at the time of tissue collection will translate into direct patient benefit since a subset of lymphomas (T-lymphoblastic lymphoma) may present exclusively as an anterior mediastinal mass and the tissue obtained from this site may be the only one available to evaluate prognostic markers and potential targetable molecular alterations. Once a proper initial diagnostic work-up has been performed, a case can be transferred to a hematopathologist for assistance with a refined diagnosis. In this review, we focus on the practical diagnostic approach to the most common prevascular/anterior mediastinal lymphomas with an emphasis on the findings in small biopsies and provide best practice tips for case triage.

Aero-digestive fistulas (ADFs) are pathologic connections between the airways and gastrointestinal system. These most commonly occur between the central airways and esophagus. Fistulas may develop congenitally or be acquired from a benign or malignant process. Most fistulas presenting in adulthood are acquired, with similar rates of benign and malignant etiologies. Symptoms may severely impact a patient's quality of life and result in dyspnea, cough, and oral intolerance. ADFs have been associated with increased mortality, often related to pneumonias and malnutrition. Management is multifaceted and includes a multidisciplinary approach between the pulmonologist, gastroenterologist, and thoracic surgeon. While definitive management can be achieved with surgery, this is typically reserved for benign causes as surgical repair is often impractical in patients with advanced malignancies. With malignant causes, less invasive endoscopic and/or bronchoscopic interventions may be indicated. Stenting is the most common non-surgical invasive intervention performed. Stents can be placed in the esophagus, airway, or both. There is limited data that suggests outcomes may be better when esophageal stenting is performed with or without airway stenting. Airway stents are indicated when there is airway compromise, inadequate sealing of the fistula with an esophageal stent alone, or when an esophageal stent cannot be placed. This review will provide an overview of approaching ADFs from the bronchoscopist's perspective.