Background. In recent years, it has been reported that virtual bronchoscopy simulation is effective for the trans-bronchial biopsy of peripheral pulmonary lesions. However, because the three-dimensional bronchial structure is generated from two-dimensional computed tomography (CT) images, the accuracy of virtual bronchoscopy is questionable. Purpose. To determine whether or not virtual bronchoscopy is superior to a two-dimensional interpretation, even that obtained by skilled bronchoscopists, CT image readings were used to determine the bronchial pathway to the target lesion. Methods. Pulmonologists with 5 to 31 years of bronchoscopy experience were asked to determine the bronchial pathway to the target lesion on CT images. The study included two model cases that had been diagnosed with peripheral lung cancer using a trans-bronchial lung biopsy with virtual bronchoscopy. In Case 1, a non-target bronchus was occluded by sputum. In Case 2, the normal bronchial structure was substantially altered by large bullae. The bronchoscopists were directed to interpret the chest CT images without any time restriction. They were then asked to identify the next route at each bronchial bifurcation on the virtual bronchoscopy images from the trachea to the target bronchus. The criterion for test completion was the selection of an incorrect route. Results. The correct answer rate at the third- and fourth-order bronchi was 88% and 50%, respectively, in Case 1, and 38% and 6%, respectively, in Case 2. The correct answer rate was not related to the years of bronchoscopy experience. Conclusions. This study showed that the degree of experience of bronchoscopists was independent of their ability to identify the pathway to peripheral lung lesions on CT images. The lack of inter-individual differences in the interpretation ability may support the usefulness of virtual bronchoscopy.

Case. A 94-year-old man presented after aspirating a dental crown during dental treatment. A chest X-ray showed a bronchial foreign body. He was referred to our hospital for extraction of the bronchial foreign body. Bronchoscopy showed a dental crown in the left lower bronchus. We removed the dental crown using a basket-type grasping forceps. At the time of the first bronchoscopic examination, multiple white nodules were noted in the trachea. We repeated the bronchoscopy and biopsied the nodules. The histopathologic findings confirmed a diagnosis of tracheobronchopathia osteochondroplastica (TO). Conclusion. With ageing, diseases associated with aspiration increase. Bronchial foreign bodies are also associated with aspiration. TO may be caused by chronic inflammation. There is a possibility that TO will increase because of aspiration-associated chronic inflammation.

Case. A 28-year-old woman with cerebral palsy was admitted with failure of ventilation due to obstruction of sputum. As hypoxemia, hypercapnia and apnea prevented her from leaving the respirator, tracheostomy was performed. She was discharged once, but returned to our hospital on suspicion of tracheal stenosis. Bronchoscopy revealed growth of granulation tissue on the tip of the cannula and collapse of bronchial lumen in the expiratory phase. CT scan revealed the trachea was shifted to the right because of scoliosis and oppression by the brachiocephalic trunk, right clavicle and a vertebral body on the tip of the cannula. To keep patent the trachea, the spiral cannula whose depth could be adjusted was inserted to just above the carina by bronchoscopy. Though bronchoscopic ablation was repeated to excise granulation, she suffered from recurrent suffocation by airway obstraction. Surgical intervention of partial resection of the right clavicle and covering the trachea by anterior cervival muscle away from the brachiocephalic trunk was performed to prevent tracheal compression and tracheoarterial fistula. Clinical features improved after surgery, but collapse of the tracheal lumen in the expiratory phase still remained. To manage the situation an I-shaped Dumon stent was inserted, and the clinical course has been satisfactory after this procedure. The spiral cannula was changed to a T-tube, and she could leave the respirator at last.

Background. Malignant lymphoma of lung origin is a rare disease. Its frequency is about 0.4% of all malignant lymphomas, and no more than 0.5-1.0% of all lung cancer. We report a case of mucosa associated lymphoid tissue (MALT) lymphoma of lung origin. Case. A 69-year-old woman complained of cough and dyspnea. The chest radiograph in a local clinic showed widely spread consolidation and pleural effusion in the right lung field. She was given antibiotics for a week after consulting our hospital, but consolidation was exacerbated. Right pleural effusion was increased, so chest drainage was done. IgM was elevated in the serum, and IgM λ type M protein was detected by immunoelectrophoresis. In bronchoscopy, lymphocytes elevated in the bronchoalveolar lavage fluid (BALF) and CD20 positive lymphocytes infiltrated lung tissue with formation of lymphoepithelial lesion gained by trans-bronchial lung biopsy. Later, CD20 positive lymphocytes elevated in pleural effusion, and we regarded them as detected in the lung tissue. Superiority of λ type were proved in flow cytometry, and we diagnosed MALT lymphoma of lung origin. Conclusion. MALT lymphoma of lung origin is a rare disease. We suspected bacterial infection at first, but diagnosed MALT lymphoma of lung origin.

Background. Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) allows us to less-invasively diagnose mediastinal or hilar lymph nodes, while more peripheral lymph nodes are typically considered difficult to approach using EBUS-TBNA. We report a case where segmental lymph node metastasis of gum cancer was diagnosed using EBUS-TBNA. Case. A 69-year-old man, who had received subtotal mandibulectomy for the treatment of gum cancer, presented with a moderately swollen segmental lymph node of the right lower lobe of the lung. We performed EBUS-TBNA for the biopsy. Bronchofiberscopy was accurately inserted in the segmental bronchus and specimens were safely obtained. Histopathological examination revealed gum cancer metastasis. Conclusion. This case suggests that EBUS-TBNA is an effective and minimally invasive procedure for the diagnosis of segmental lymph nodes.

Background. A malignant tumor metastasizing to the trachea/tracheal lumen is relatively rare, and liver cancer metastasizing to the tracheal lumen and blocking the central airway is even rarer. Case. A 75-year-old woman underwent right lower lobectomy for a metastatic lung tumor 3 years after undergoing surgery for liver cancer. Subsequently, she had been relapse-free for 2 years but was referred to our department because of the appearance of bloody phlegm during follow-up. A tumor was found immediately above the carina trachea on chest computed tomography, and liver cancer metastasizing to the tracheal lumen was suspected based on the clinical course. The tumor was resected to the maximum extent possible via rigid bronchoscopy to relieve the airway stenosis. The pathological diagnosis was liver cancer metastasizing to the tracheal lumen. The patient is currently under observation as an outpatient. Conclusion. We encountered a case of liver cancer metastasizing to the tracheal lumen in which the tumor was resectable via rigid bronchoscopy. As shown in our present case, rigid bronchoscopic treatment for tracheal neoplasms causing airway stenosis is a safe procedure that enables secure maintenance of the airway and also effectively treats bleeding.

Background. Although the utility of endoscopic bronchial occlusion using endobronchial Watanabe spigot for refractory pneumothorax has been reported, there are no reports on their use in young people. Case. A 16-year-old boy (139 cm, 27 kg) had been undergoing outpatient treatment with prednisolone because of graft-versus-host disease and interstitial pneumonia following bone marrow transplant at 6 years of age to treat leukemia which occurred at the age of 4 years. It is difficult to control interstitial pneumonia, and his lung had been diagnosed with air leak syndrome. In 2013 (at 14 years of age), because of the prolonged air leak he underwent endoscopic bronchial occlusion using endobronchial Watanabe spigot. He exhibited improvement. In 2015, the pneumothorax relapsed, and the air leak was prolonged. Endoscopic bronchial occlusion using endobronchial Watanabe spigot was performed again, and autologous blood was instilled in the pleural space. The air leak ceased. Conclusion. We encountered a case in which a small, teenage patient with refractory pneumothorax responded to endoscopic bronchial occlusion therapy using endobronchial Watanabe spigot.

Background. The origin of a broncholith is erosion of the bronchus due to calcification of a lymph node or foreign material in the bronchus. However, there are a few reported cases of broncholithiasis due to a fungal infection. Additionally, many cases of broncholithiasis have respiratory symptoms, such as a cough and hemoptysis. It is also rare for asymptomatic broncholithiasis to be identified by a chest CT examination. Case. An abnormality was noted by a chest CT examination in a 61-year-old man and he was admitted to our hospital. Chest CT showed a calcified tumor in the left B¹⁺² bronchus and wedge-shaped consolidation in left S¹⁺². Bronchoscopy was performed for a detailed examination. A brown material was removed from the left B¹⁺²a using biopsy forceps and saline. The histopathological diagnosis was broncholithiasis and the broncholith was occupied by numerous hyphae from a fungus, such as Aspergillus. There was no recurrence of broncholithiasis after bronchoscopy. Conclusion. It is rare to identify an asymptomatic broncholithiasis found by chest CT and perform endoscopic stone removal. We must examine more cases to determine therapeutic indications for asymptomatic cases.

Background. Endobronchial ultrasonography guided transbronchial needle aspiration (EBUS-TBNA), which is a type of real time needle biopsy performed in the diagnosis of mediastinal lymphadenopathy, is considered to cause few complications and be highly useful in the nodal staging of lung cancer. However, recently, the usefulness of EBUS-TBNA for peripheral lesions in the lung fields has been reported, and transbronchial and transtracheal approaches have been attempted. Here, we report a case of metastatic lung tumor adjacent to subsegmental bronchus which were not identified by endoscopy, approached by using EBUS-TBNA. Case. A 60-year-old woman was referred to our department for a thorough examination of abnormal shadows in the chest radiograph. Computed tomography showed nodules adjacent to lower B⁴b in S⁴ of the right lung, and bronchoscopy was performed for diagnosis. While no lesions were observed on endoscopy, hypoechoic lesions in lower B⁴b were detected by radial EBUS. By blindly wedging the Convex EBUS probe into the bronchus with reference to the fluoroscopic images obtained from previous radial EBUS, lesions were successfully visualized. We diagnosed lung metastasis of rectal cancer based on a biopsy with EBUS-TBNA at the same site. Conclusion. EBUS-TBNA is a useful tool to diagnose even for pulmonary lesions adjacent to the subsegmental bronchus by this method.

Background. Transbronchial needle aspiration cytology (TBAC) and a transbronchial needle aspiration biopsy are diagnostic approaches for mediastinal or hilar lymphadenopathy. Pathological diagnoses can differ between cytology and histology in some cases. Case. Lung tumor shadow was identified in a 70-year-old man, and chest computed tomography showed subclavicular, mediastinal and hilar lymphadenopathy. TBAC from a subcarinal lymph node suggested small cell carcinoma, but an immunohistochemical analysis of the transbronchial needle aspiration biopsy and a cell block from the TBAC samples suggested adult T-cell leukemia lymphoma. The lymphoma showed a continued response for a year after chemotherapy. Conclusion. Differentiating between small cell carcinoma and lymphoma using cytology alone is difficult in some cases. The collection of sufficient samples for cell blocks is important in cases with limited tissue samples, considering the need to analyze both the morphology and immunohistochemical features.

Background. There are few reports of tracheobronchial lesions due to nontuberculous mycobacterial infections. Case. A follow-up CT scan revealed a nodule with a cavity in a 67-year-old man who had previously undergone surgery for sigmoid colon cancer in his left upper lobe. He was admitted to our hospital in March 201X. Mycobacterium fortuitum (M. fortuitum) was cultured from a sample obtained during bronchoscopy, and the patient was followed without medication. A CT scan in May 201X+1 revealed that the left upper lobe nodule had become larger and showed the appearance of another nodule in the right main bronchus. Mycobacterium avium (M. avium) was cultured from a sputum specimen. Thus, we started antibiotic therapy in September of that year, and the patient's sputum culture became negative. In February 201X+2 M. fortuitum grew in sputum culture, and bronchoscopy was performed. We found a tumefactive lesion at the membranous portion of the right main bronchus, which had been observed on the CT scans, and necrotic material was drained by brushing. We considered the lesion to have been caused by M. fortuitum infection, and added levofloxacin to his antibiotic therapy. Thereafter, the clinical course was good. Conclusion. We reported the case of a patient with a bronchial wall lesion that was suspected to be a M. fortuitum infection.

Background. Sometimes, the cause of respiratory failure cannot be determined by serology in immune suppressed patients, and bronchoscopy hence needs to be performed. However, performing bronchoscopy in patients with severe respiratory failure is sometimes difficult and associated with high risks. Case. A 60-year-old woman, who received prednisolone and methotrexate because of rheumatoid arthritis, visited a hospital due to dyspnea on effort. Positron emission tomography-computed tomography scan revealed diffuse consolidation and lung nodules, which showed fluorodeoxyglucose uptake. After she stopped taking methotrexate, the affected area in the lung worsened, and she was admitted to our hospital for severe respiratory failure. We were unable to determine the cause of respiratory failure by serology and hence performed flexible bronchoscopy during noninvasive positive pressure ventilation. There were no problems related to oxygenation or any complications during the bronchoscopy, and we were able to make the diagnosis of secondary organizing pneumonia due to rheumatoid arthritis. Treatment with corticosteroids was administered and was extremely effective; as a result, she became ambulatory and was discharged from the hospital. Conclusion. Bronchoscopy during noninvasive positive pressure ventilation may be a useful diagnostic method under sufficient risk management.

Background. There is no previous report of autoimmune hemolytic anemia manifesting after bronchoscopic examination. Case. A 73-year-old woman presented with a dry cough. Computed tomography revealed a nodule measuring 4×2 cm in size at the base of the left lung. A bronchoscopic examination revealed malignancy in the form of adenocarcinoma. Two days later, the patient was admitted to the emergency department with complaints of dizziness. The direct Coombs test yielded positive findings, and the patient was diagnosed with autoimmune hemolytic anemia. The patient received treatment with oral steroids because of the positive Coombs test results, but no first-line chemotherapy for lung cancer was performed. However, her performance status gradually declined. The patient died 2 months after the initial administration of oral steroids. Conclusions. This report highlights the possibility of autoimmune hemolytic anemia occurring after bronchoscopic examination in a patient with primary lung cancer.