Our institution received a referral for an 82-year-old man with a 27-mm solid nodule in the right upper lobe of the lung on computed tomography. We also detected a supernumerary tracheal bronchus branching from the right wall of the trachea, which was distributed in the right apical segment. The apical segment, the posterior segment, and the anterior segment branches originated from the right upper bronchus, with no regional bronchial defect noted. A squamous cell carcinoma was revealed by the transbronchial biopsy of the lung nodule. Subsequently, we performed video-assisted thoracoscopic right upper lobectomy and lymph node dissection. During the procedure, we safely transected the tracheal bronchus, which branched into the right upper lobe of the lung at the inferior margin of the azygos vein, using a stapler. The incidence of the "supernumerary type" tracheal bronchus is relatively rare compared to the "displaced type," and the coincidence of aberrant vascular structures has also been reported. Thoracic surgeons should consider these anatomical variations when planning surgical procedures.

Esophageal stenting, which is a treatment for esophagotracheal fistula, can cause severe complications, such as perforation and bleeding, and the rare complication of respiratory failure due to tracheal compression. This study presented the case of a 51-year-old man who was referred to our hospital for airway stent placement in an esophagotracheal fistula. He had previously undergone chemoradiotherapy and immunotherapy for advanced esophageal cancer with tracheal invasion. A tracheoesophageal fistula developed during therapy and was successfully treated with the implantation of a tracheal stent with a length of 4 cm. Afterward, an esophageal stent with a length of 10 cm was inserted to improve esophagostenosis. However, sudden dyspnea developed 3 days after esophageal stent placement. Chest computed tomography and bronchoscopy revealed that the esophageal stent was placed 4 cm proximal to the tracheal stent and the trachea was extremely constricted by the esophageal stent. He was intubated and ventilated and an additional tracheal stent was implanted the following day. Following implantation, the stenosis improved and he was discharged without any complications. Airway stenosis due to esophageal stenting is a rare but potentially life-threatening complication. Therefore, esophageal stent-related complications should be considered when planning stent insertion.

Pulmonary hypertension due to amyloidosis is rare. We report a case of AL-type amyloidosis who presented with pulmonary hypertension. A 48-year-old woman presented with dyspnea on exertion. She was diagnosed with pulmonary hypertension by pulmonary artery Swan-Ganz catheterization. Imaging examinations, such as chest computed tomography and ventilation-perfusion scintigraphy failed to reveal the etiology of pulmonary hypertension. However, a transbronchial lung Cryobiopsy revealed the diagnosis of pulmonary amyloidosis. Thus, transbronchial lung Cryobiopsy might be useful for the diagnosis in cases presenting with pulmonary hypertension of unknown etiology.

Lung lymphoepithelial carcinoma, formerly known as lymphoepithelioma-like carcinoma, occurs rarely. A 39-year-old woman presented to our hospital with a chief complaint of dizziness and was ultimately diagnosed with anemia caused by bleeding from a solitary small intestine metastasis of primary lung lymphoepithelial carcinoma. After resection of the primary and metastatic tumors, the patient received platinum-doublet adjuvant chemotherapy and immune checkpoint inhibitors consecutively. Intestinal lung cancer metastases generally occur rarely and have a poor prognosis. There are no reports of primary lung lymphoepithelial carcinoma with solitary metastasis to the small intestine, as in this case. She has been alive without recurrence for a year. This case demonstrates the potential of multidisciplinary treatment for lung lymphoepithelial carcinoma with solitary metastasis, including resection of the metastatic site.

There have been rare reports of B3 displacement from the right middle lobe (RML) bronchus. We report a case of thoracoscopic resection of the RML and anterior segment (S3) for RML lung cancer with B3 displacement from the RML bronchus. A 70-year-old woman was admitted to our hospital due to an abnormal shadow detected on chest radiography. Chest computed tomography (CT) revealed a middle lobe tumor and a displaced B3 bronchus originating from the RML. The tumor measured 30 mm in diameter; further, a transbronchial biopsy confirmed the adenocarcinoma diagnosis. We successfully performed a complete thoracoscopic resection of the RML and anterior segment of the right upper lobe. Given the limited knowledge of the lymphatic flow around the displaced bronchus, we opted for a reasonable approach to lymph node dissection. Preoperative assessments, including chest CT, bronchoscopy, and three-dimensional reconstructed CT scans, can facilitate preoperative bronchial and pulmonary vasculature identification.

Primary pulmonary non-Hodgkin's lymphoma (PP-NHL) poses diagnostic challenges owing to its rarity, nonspecific clinical symptoms, and elusive imaging findings. We present a case of a 67-year-old woman who was admitted to the hospital with exacerbation of cough and dyspnea. On admission, her SpO₂ was 88% (10 L/min reservoir mask), with bilateral diffuse ground-glass opacities, centrilobular nodules, and thickened interlobular septa in both lung fields. There was no significant lymphadenopathy, apart from small periaortic lymph nodes. Although she had severe respiratory failure, transbronchial lung biopsy (TBLB) was performed to confirm the diagnosis. Septic shock and acute renal failure necessitated vasopressor support along with the initiation of methylprednisolone 1 g pulse therapy. Cytology and histopathology confirmed anaplastic lymphoma kinase (ALK) + anaplastic large cell lymphoma (ALCL). Respiratory improvement allowed ventilator withdrawal by day 8, and cyclophosphamide, hydroxydaunorubicin, vincristine, and prednisone (CHOP) therapy commenced on day 18. Although ALCL constitutes 13% of reported PP-NHL cases, ALK+ ALCL with diffuse pulmonary involvement is rare. For patients with severe respiratory failure, the life-threatening complications of TBLB should be fully considered. For our patient, the diagnostic value of TBLB was high due to her complex medical condition, which included respiratory failure, acute renal failure, and sepsis.

Mediastinal schwannomas are relatively rare; therefore, limited cases have been reported. Endoscopic ultrasound with bronchoscope-guided fine-needle aspiration (EUS-B-FNA) reportedly has a good diagnostic yield. An 87-year-old man with a chronic cough due to asthma was referred to our hospital with a mediastinal tumor adjacent to the trachea and esophagus. Magnetic resonance imaging revealed cystic lesions in the tumor, and the risk of complications was reduced by avoiding aspiration of the cystic lesions using endobronchial ultrasonography. EUS-B-FNA was performed under intravenous anesthesia. Histological examination of the obtained tissue revealed a mediastinal schwannoma.

Introduction: Commercially available bronchoscopes cannot visualize the peripheral airways, which are approximately 1 mm in diameter. We developed a 0.97-mm fiberscope and successfully observed the peripheral airways down to the alveolar level using surgically resected lung lobes.

Technical Report: To imitate the lung environment in vivo as much as possible, a resected lung was placed in a special desiccator to create a negative-pressure environment. A fiberscope with an angled tip was inserted through the side canal and advanced into the target bronchus.

Conclusions: Many respiratory diseases, including lung cancer, arise in the peripheral airways. In the future, observation, biopsy, and treatment of peripheral airways will be important. This technology will help us realize these goals.