Background. Endobronchial metastases from malignant tumors are relatively rare, with breast cancer, kidney cancer, and colorectal cancer being the most common primary tumors. Endobronchial metastases of renal cell carcinoma bleed easily and carry a high risk of severe bleeding. Case. The patient was a 51-year-old woman who was diagnosed with left renal cell carcinoma (T3bN1M1, stage IV) in 2012. She had received various treatments, excluding the use of molecular-targeted drugs. In May 2020, she visited our hospital because of dyspnea. Chest computed tomography showed obstruction of the left main bronchus, and a bronchoscopy was performed under invasive mechanical ventilation due to acute respiratory failure. The left main bronchus was almost completely obstructed due to a rough polypoid tumor with redness and bleeding. Bronchial artery embolization was first performed due to the high risk associated with bleeding. After bronchial artery embolization, airway stent placement was performed, and her respiratory condition improved. Molecular-targeted drugs were administered, and radiotherapy was performed for endobronchial metastatic lesions. A long-term survival has been obtained. Conclusion. The safe placement of an airway stent after bronchial artery embolization improved the prognosis of a patient with acute respiratory failure due to endobronchial metastases of renal cell carcinoma.

Background. Pleural angiosarcoma is a rare disease that is difficult to diagnose, shows rapid growth, and has a poor prognosis. Case. A 73-year-old man with left pleural effusion and a history of asbestos exposure was referred to our hospital. Thoracoscopy under local anesthesia was performed, revealing diffuse, rough pleural thickening with scattered white protruded lesion. A pleural biopsy did not lead to a definitive diagnosis. Four months later, the left pleural effusion had massively increased on repeated thoracoscopy. Pleural bleeding and numerous irregular red tumors were observed in the thoracic cavity. A pleural biopsy revealed proliferation and invasion of CD31-positive spindle cells, which turned out to be angiosarcoma. This patient did not respond to outpatient chemotherapy and died six months after the diagnosis. Conclusion. We encountered a rare case of primary pleural angiosarcoma in which rapid pleural changes were visualized by thoracoscopy. It is difficult to suspect or diagnose angiosarcoma based on early lesions in such cases, so a surgical biopsy should be considered.

Background. Respiratory function tests may be used to objectively evaluate the degree of airway stenosis, before and after airway intervention. Case. The patient was a 40's woman who had previously undergone surgery and chemotherapy for colorectal cancer in 200X-7, and radiotherapy for mediastinal lymph node metastasis and tracheal invasion in January, 200X-1. She was referred to our hospital for airway intervention in January, 200X due to progressive airway stenosis on chest computed tomography. Bronchoscopy revealed the invasion of lymph node metastasis on the left side of the lower trachea. Tumor resection was performed using a high-frequency electrosurgical snare under a flexible bronchoscope. Despite improvement in her subjective symptoms and the peak expiratory rate in respiratory function tests, she was referred to our hospital again on March, 200X+1, due to the progression of stenosis. Tumor resection was performed via cryoprobe under flexible bronchoscopy, and a Dumon Y stent was placed under rigid bronchoscopy. Her respiratory function test results, including peak expiratory rate, subsequently improved. Conclusion. We reported a case of airway stenosis due to mediastinal lymph node metastasis of colorectal cancer, in which subjective symptoms and respiratory function test results improved after two airway interventions.

Background. Various marking techniques for the identification of small impalpable lung nodules have been reported. Case. A 72-year-old man who had undergone surgery for bladder and rectal cancer presented with a solitary small lung tumor located in the right S³ on chest computed tomography (CT). Due to tumor enlargement, it was suspected to be metastatic; thus, surgery was performed. Because the tumor was located near the B³bi, we performed presurgical coil marking using an endobronchial ultrasonography with a guide-sheath. During surgery, we identified the marking coil using X-ray fluoroscopy and subsequently resected the target tumor and marking coil. Conclusion. This method was safe and useful for marking small impalpable lung nodules.

Background. Most elderly pneumothorax patients are treated by nonsurgical procedures. Few papers have been reported on surgery for refractory pneumothorax with COVID-19. Case Presentation. The patient was a 100-year-old man. A cluster of COVID-19 cases had occurred at his facility. He presented with a fever and decreased oxygenation and was taken to the hospital. He was suspected of having COVID-19. A polymerase chain reaction test for SARS-CoV-2 was positive, and chest X-ray revealed right pneumothorax. His COVID-19 symptoms were quite mild and quickly resolved; however, the air leakage of his right lung persisted, and the lungs did not expand. He underwent video-assisted thoracoscopic bullectomy and was discharged from the hospital without complications. In this case, a lung bulla was observed in the right lung, which was expected to have caused the pneumothorax. There have been several reports that COVID-19 causes pneumothorax. Therefore, COVID-19 may have been the cause of the pneumothorax in this case. Conclusion. Although most elderly patients are treated by nonsurgical procedures, surgery should be considered after evaluating the patient's general condition and risk of complications.

Background. Bilious pleural effusion is a rare condition in which intra-abdominal bile transitions into the thoracic cavity, causing the pleural fluid to turn brown. It is considered to be caused by abdominal disease. Case presentation. A 79-year-old woman presented to the hospital for the examination of dyspnea on exertion and right pleural effusion. Brown to black pleural effusion was found on thoracic drainage, and a diagnosis of bilious pleural effusion was made based on elevated pleural bilirubin and glycocholic acid levels. Thoracoscopy under local anesthesia was performed, and nodular lesions were found on the diaphragmatic pleura. A biopsy of the same area revealed a diagnosis of adenocarcinoma of the lung. Contrast-enhanced computed tomography of the thorax and abdomen showed no obvious abnormalities in the hepatobiliary or pancreatic regions. This case was considered to involve pleural seeding at the diaphragm, with invasion of the liver causing bile to transition into the thoracic cavity. Conclusion. In cases of bilious pleural effusion caused by thoracic disease, thoracoscopy under local anesthesia is useful for a closer examination.