Background/Objective. Osimertinib is generally used as a second-line or later therapy after the detection of a T790M mutation by a rebiopsy in non-small-cell lung cancer (NSCLC). However, few reports have described the results of rebiopsies in NSCLC patients with EGFR mutations. The aim of our retrospective study was to identify factors affecting the detection of a T790M mutation in patients who undergo a rebiopsy. Method. This study included subjects who had advanced NSCLC with EGFR mutations and underwent rebiopsies at our hospital from January 2016 to April 2018. We investigated the success rate of rebiopsies, the detection rate of T790M, and the influential factors related to rebiopsies and T790M detection. Result. The subjects were 58 patients who underwent a rebiopsy. The success rate of the first rebiopsy was 74.1% (43/58), and the T790M-positive rate was 41.9% (18/43). The success rate of the second rebiopsy was 78.6% (11/14), and the T790M-positive rate was 63.6% (7/11). The overall number of rebiopsies was 75, the overall success rate of rebiopsies was 76.0% (57/75), and the overall T790M-positive rate was 43.9% (25/57). No statistically significant factors affecting the T790M-positive rate were observed in this study. In addition, the characteristics of patients who underwent multiple rebiopsies as well as the characteristics of those who only underwent a single rebiopsy were examined. The frequency of experiencing multiple rebiopsies was higher in patients with cytotoxic agents than in those without (P=0.005). Conclusion. We were unable to detect any factors affecting positivity for a T790M mutation. The frequency of having undergone several rebiopsies seemed to be higher in patients who received any cytotoxic chemotherapy than in those with no such treatment. We believe that repeated specimen collection may increase the detection rate for T790M mutations.

Background. Previous studies demonstrated the usefulness of endobronchial ultrasonography with a guide sheath transbronchial biopsy (EBUS-GS-TBB) in the diagnosis of peripheral pulmonary lesions. However, factors affecting the diagnostic yield of EBUS-GS-TBB have not been fully investigated. Objective. We performed a retrospective analysis to identify factors affecting the diagnostic yield of EBUS-GS-TBB in peripheral pulmonary lesions. Methods. A total of 118 patients diagnosed using EBUS-GS-TBB in Nippon Medical School Hospital between July 2016 and April 2018 were evaluated. In 101 patients with a definitive diagnosis, diagnostic factors of peripheral pulmonary lesions using EBUS-GS-TBB were retrospectively analyzed. According to the probe location, echo findings were divided into four groups: 'within', 'outside', 'broadly adjacent to' and 'narrowly adjacent to'. When the angle of the lesion around the probe in the EBUS-GS-TBB images was from ≥180 to <360 degrees, the echo finding was defined as 'broadly adjacent to'. Other findings in the 'adjacent to' group were classified as 'narrowly adjacent to'. Results. The rate of definitive diagnosis using EBUS-GS-TBB was 78.2% (79/101 patients). A multivariate analysis revealed that the echo findings of 'within' or 'broadly adjacent to' were a significant predictive factor (odds ratio [OR]=4.25; P<0.01). The diagnostic rate in patients with pulmonary emphysema was significantly lower than the rate reported in other patients (OR=0.29; P=0.02). In patients who underwent thin-section computed tomography, 'bronchus sign' was a significant predictive factor versus patients who did not undergo thin-section computed tomography (83.7% vs 42.9%, respectively, OR=6.86; P=0.03). Conclusion. Echo findings of 'within' and 'broadly adjacent to' should be obtained to improve the diagnostic yield of EBUS-GS-TBB. The diagnostic yield of EBUS-GS-TBB was low in patients with pulmonary emphysema. Presence of pulmonary emphysema before EBUS-GS-TBB should be evaluated.

Background. IgG4-related disease develops in various organs, and the clinical features are very diverse. Case. A 62-year-old man had a chief complaint of a fever and productive cough. Computed tomography showed not only wall thickening in the trachea and central bronchi but also mucosal thickening in the paranasal sinus, mainly the maxillary sinus. Although bronchoscopy revealed marked bronchial mucosal edema and multiple white nodules, the bronchial mucosal biopsy specimens did not provide a definite diagnosis. Therefore, we performed a nasal septum biopsy and found the marked infiltration of IgG4-positive plasma cells with an IgG4/IgG ratio exceeding 50%. Due to the high value of serum IgG4 in addition to these findings, we diagnosed the patient with IgG4-related disease. After the administration of corticosteroids (prednisolone 35 mg/day), the patient's symptoms and the above imaging findings had improved. Conclusion. Wall thickening in the central airway is a rare condition in IgG4-related disease. A nasal septum biopsy might be useful for the diagnosis of IgG4-related disease.

Background. Photodynamic therapy (PDT) using tumor affinity photosensitizers and low-level lasers is a promising method not only for managing early-stage lung cancer but also for palliation in advanced cases with central airway stenosis. However, its efficacy for metastatic bronchial cancer is unclear. Case. A 55-year-old woman with recurrent metastatic colon cancer had been treated with chemotherapy. She had undergone bronchoscopic tumor debulking twice for symptomatic bronchial metastases; however, cough and dyspnea recurred three months after the second operation. PDT was therefore performed with second-generation talaporfin sodium (Laserphyrin^®). The mass started shrinking during the procedure, and her symptoms were quickly resolved. She has not required any further procedures for her bronchial metastasis in two years and eleven months. Conclusion. PDT may be a viable palliative therapy option for bronchial stenosis due to metastatic cancer.

Background. The development of a tracheo vascular fistula is a rare, critical complication of tracheostomy. Prompt management of this complication is of crucial importance. We herein report a case of a tracheo subclavian arterial fistula that was urgently treated using an endovascular stent, followed by the placement of a custom-made tracheostomy tube for risk reduction. Case. A 23-year-old male with Duchenne muscular dystrophy and respiratory failure due to ischemic encephalopathy after resuscitation suffered a trachea arterial fistula 19 days after tracheostomy. Initial bleeding was managed via overinflation of the tube cuff and digital compression. On the following day, enhanced computed tomography (CT) revealed the presence of a tracheo right subclavian arterial fistula. Massive bleeding occurred immediately after transfer from the CT stand. Concurrent with digital compression from the tracheal stoma and transfusion, placement of an endovascular stent into the right subclavian artery stopped the bleeding. The patient suffered a thoracic transformation because of his muscular dystrophy, which was considered to be one of the reasons for the fistula. A custom-made tracheostomy tube adjusted to the shape of the trachea was used to avoid excessive contact with the tracheal wall. The patient did not suffer any complications for one year. However, one year after the intervention, tracheal bleeding recurred, and the patient expired the following day. Conclusion. A patient with muscular dystrophy suffered a tracheo subclavian arterial fistula after tracheostomy and was managed through the placement of an endovascular stent and a custom-made tracheal tube.

Background. Tracheal papillomas are benign, tracheal, tumorous manifestations of recurrent respiratory papillomatosis. Case. A 65-year-old woman was referred to our hospital due to pharyngeal discomfort and dyspnea on exertion. She produced audible stridor when recumbent. Chest computed tomography revealed multiple tracheal tumors with airway obstruction. Bronchoscopic imaging supported this finding, and the patient was pathologically diagnosed with tracheal papillomatosis. Human papillomavirus-11 was detected via viral genomic testing. She underwent two separate trials of bronchoscopic tumor resection using argon plasma coagulation. The first trial was focused on alleviating the airway obstruction, whereas the second one was focused on resecting the remaining tumors. Her symptoms improved after the first resection, and no recurrence was detected after the second resection procedure. Conclusion. Tracheal papillomas occasionally cause tracheal stenosis. Bronchoscopic tumor resection was effective in our patient.

Background. Although cases involving bronchial embolization using an Endobronchial Watanabe Spigot for intractable pneumothorax have been reported in recent years, their use in the treatment of patients with pulmonary tuberculosis is rare. Case. A man in his 60s was admitted to our hospital and diagnosed with tuberculosis and left pneumothorax. The patient's pulmonary tuberculosis was treated with four antibiotics with placement a chest tube for drainage. Pulmonary air leakage persisted for 5 months even though the tuberculosis was cured. Thus, thoracoplasty was performed for intractable pneumothorax; however, air leakage recurred on postoperative day 7. Local compression to the chest wall and drainage were continued for 3 months because compression controlled the air leakage; however, the treatment was not successful. Finally, we performed endobronchial embolization using an Endobronchial Watanabe Spigot in the affected bronchus. After embolization, the air leakage was completely controlled. The chest tube was removed on the 23rd day after embolization, and the patient was discharged from the hospital. Air leakage has not recurred during 8 months of follow-up. Conclusion. Endobronchial embolization was shown to be an effective and appropriate treatment for intractable pneumothorax in a patient with pulmonary tuberculosis.

Background. Between 30% and 40% of cases of bacterial pneumonia are associated with pleural effusion. However, empyema is rare, occurring in only 0.5% to 2% of cases. Empyema has various causes, but can be intractable and sometimes fatal when it develops due to host factors, such as cerebral palsy or severe motor and intellectual disabilities. However, cases of empyema surgery for severe motor and intellectual disabilities patients are rare. Case. We encountered a case of severe motor and intellectual disabilities in a 33-year-old woman with an ECOG PS of 4 whose disability had been caused by a head injury at 1 year of age. The patient was referred to us because of severe and prolonged inflammation and massive left pleural effusion. Chest ultrasonography showed a large pleural effusion with multiple septations. Pleural fluid culture yielded methicillin-resistant Staphylococcus aureus (MRSA). The patient was diagnosed with acute left empyema and underwent video-assisted thoracoscopic decortication and drainage with intrathoracic irrigation. Seven days after surgery, sufficient reexpansion of the lung was achieved, and the chest drain was removed. The patient was transferred back to the referring hospital 14 days after surgery. Conclusion. The life expectancy of severely disabled patients is extended by the improvement of management approaches. However, due to the particularity of the surrounding environment, empyema due to resistant bacteria, such as MRSA, is becoming a problem. The early diagnosis and application of appropriate treatment are considered essential for improving the prognosis.

Background. In cases of bronchial hemorrhaging occurring in a patient who is allergic to the contrast agent, bronchial artery embolization is difficult. Case. A 70-year-old woman with hemoptysis and dyspnea presented to a hospital. After the injection of contrast agent prior to chest computed tomography (CT), her blood pressure suddenly decreased, and airway narrowing occurred because of anaphylactic shock accompanied by a rash. Adrenaline and prednisolone were injected to improve the symptoms. Bronchoscopy revealed bleeding with clots in the right upper lobe bronchus, and chest CT showed an area of consolidation with diameter of 33×22 mm in the right upper lobe S¹. Bronchial hemorrhaging from right upper lobe S¹ was diagnosed. A reassessment CT scan showed no abnormal shadow in the right upper lobe, and no special findings were found on bronchoscopy. The patient was therefore referred to our hospital for further follow-up. In cases of the sudden occurrence of respiratory tract bleeding in a patient with contrast allergy, it is difficult to perform bronchial artery embolization. We therefore recommended she undergo elective surgery to avoid suffocation caused by sudden bronchial hemorrhaging. The patient agreed with our suggestion. Right upper lobectomy through video-assisted thoracic surgery was performed. No pathological findings, such as arteriovenous fistula or aneurysm, were observed except for hemorrhaging in the lung tissue and lymph nodes at about 10 mm in S¹a. The postoperative course was uneventful, and the patient was discharged from the hospital 16 days after the operation. Conclusion. Our case shows that respiratory tract bleeding in a patient with contrast agent allergy can be safely treated with elective surgery.

Background. Although a transbronchial biopsy (TBB) is an effective way to make a histological diagnosis of primary lung cancer, massive hemorrhaging in the airways occasionally occurs. In such cases percutaneous cardiopulmonary support (PCPS) may be needed in addition to tracheal intubation. Since PCPS requires anticoagulation to prevent blood clots in the circuit, there are some concerns about additional hemorrhaging in cases of hemoptysis or surgery. We herein report a case of massive hemoptysis for which lobectomy was successfully performed under venovenous extra-corporeal membrane oxygenation (VV-ECMO) without the use of anticoagulants. Case. A 74-year-old female with a 35×25-mm mass in the left S¹⁰ underwent a TBB, which evoked massive hemorrhaging. She was immediately intubated and mechanically ventilated under right lung intubation, which failed to improve her oxygenation. VV-ECMO was then established and improved the oxygenation. Since hemoptysis did not stop completely, emergent surgery of left lower lobectomy with ND2a-1 lymph node dissection was performed under VV-ECMO without anticoagulation using a heparin-coated circuit. ECMO and mechanical ventilation were withdrawn on post-operative day (POD) 1, and the patient was discharged with a favorable clinical condition on POD 16. Conclusion. Emergent left lower lobectomy with ND2a-1 lymph node dissection was performed safely under heparin-coated VV-ECMO for massive hemoptysis during a TBB.

Background. It is important to make a differential diagnosis between sarcoidosis and lung cancer when chest computed tomography (CT) reveals pulmonary nodules and mediastinal lymphadenopathy. Case. A 34-year-old man presented with chest-radiograph abnormalities in an annual medical checkup. Chest CT showed mediastinal and hilar lymphadenopathy and small multiple nodules in the bilateral lung fields. A nodule present in the right upper lobe had pleural indentation, suggesting lung adenocarcinoma. Endobronchial ultrasound-guided transbronchial needle aspiration revealed no malignant cells in the mediastinal lymph nodes. Transbronchial biopsy using endobronchial ultrasonography with a guide sheath was performed on a nodule with a pleural indentation in the right upper lobe. Biopsy specimens showed numerous epithelial cells with granuloma and no malignant cells. The patient was diagnosed with pulmonary sarcoidosis. Conclusion. Clinicians should therefore choose an appropriate biopsy technique for making a definitive diagnosis of sarcoidosis versus lung cancer.

Background. The radiological findings of allergic bronchopulmonary aspergillosis (ABPA) patients are diverse, and lung collapse is a common radiological finding; however, total unilateral lung collapse is extremely rare. Case. A 70-year-old Japanese woman had been treated with inhaled corticosteroid (ICS)/long-term beta agonist (LABA) for bronchial asthma for five years and was admitted to our hospital due to total lung collapse. The bronchoscopic findings were mucoid impaction in the right main bronchus. Aspergillus fumigatus was cultured from the endotracheal sputum. She was diagnosed with ABPA according to the Rosenberg et al.'s criteria. The symptoms improved after the removal of the mucus plug by bronchoscopy and the administration of oral voriconazole and ICS/LABA. Conclusion. ABPA can be a differential diagnosis when a patient exhibits total unilateral lung collapse. In addition, physician should consider treatment strategies such as the use of oral antifungal drugs and ICS in addition to the removal of the mucus plug using bronchoscopy for patients with ABPA in whom oral corticosteroids cannot be used.

Background. While still rare, the frequency of tracheal and bronchial glomus tumors has been increasing in recent years. Case. A 56-year-old man was found to have a mass in the right upper lobe bronchus when he developed right upper lobe obstructive pneumonia. A biopsy was performed under bronchoscopy, and a diagnosis of glomus tumor was obtained. Although the indication for bronchoscopic tumor resection was considered, we decided to perform complete resection, as some cases of malignancy have been reported among glomus tumors. The right main bronchus, truncus intermedius and upper lobe bronchus were transected, and the tumor was removed. Montage-type bronchoplasty was then performed, with the right main bronchus and the truncus intermedius were anastomosed in a telescopic fashion and the upper lobe bronchus connected to the trachea via end-to-side anastomosis. There was no decline in the respiratory function after surgery, and no recurrence was detected. Conclusion. By performing bronchoplasty without lung resection for a bronchial tumor, complete resection was possible without impairing the postoperative lung function.

Background. Adenoid cystic carcinoma is relatively rare. The origin in most cases is the trachea and main bronchus. This carcinoma is considered to be slow-growing, compared with typical adenocarcinoma. Case. An 82-year-old woman complaining of dyspnea underwent flexible bronchoscopy at another hospital. She was found to have a tracheal tumor with an easy bleeding tendency just below the vocal folds. She was therefore referred to our hospital for the definitive diagnosis and treatment. Chest computed tomography showed a 1.3 cm tumor in the upper trachea and a 2.6 cm pulmonary nodule in the right S³. She underwent tracheal tumor resection with rigid bronchoscopy and a biopsy of the pulmonary lesion with flexible bronchoscopy at the same time. The histopathological findings showed adenoid cystic carcinoma of both lesions. Epidemiologically, 90% of adenoid cystic carcinomas originate in the central bronchi rather than the segmental bronchi. We therefore diagnosed this case as one with a tracheal origin and lung metastasis. Radiation therapy (40 Gy) was performed for the post-resection tracheal lesion. One month after radiation therapy, she underwent right upper lobectomy with video-assisted thoracic surgery. She has remained free from recurrence for one year since the surgery. Conclusion. We encountered a rare case of tracheal adenoid cystic carcinoma with a solitary lung metastasis at the first visit.