Endobronchial metastasis (EBM) is a rare manifestation of extrapulmonary malignancies and poses a diagnostic challenge because it can closely mimic primary bronchogenic carcinoma. Although colorectal carcinoma (CRC) is among the most common malignancies worldwide, endobronchial involvement is distinctly rare and represents an atypical pattern of metastatic dissemination. We present the case of an 83-year-old woman with a history of resected KRAS-mutant sigmoid adenocarcinoma who developed symptomatic near-complete endobronchial obstruction more than five years after complete resection by colectomy. Imaging demonstrated presumed widespread multiorgan metastatic disease, including a large left upper lobe mass, mediastinal lymphadenopathy, hepatic and adrenal lesions, vertebral lytic lesions, and bilateral pulmonary nodules. Bronchoscopy revealed an exophytic mass in the left mainstem bronchus, causing near-complete luminal obstruction. Multimodal endoscopic debulking using a cautery snare, argon plasma coagulation (APC), and laser ablation successfully restored airway patency. Histopathology confirmed moderately differentiated metastatic colonic adenocarcinoma with CK20 and CDX2 positivity. This case highlights that CRC can recur with aggressive dissemination to rare metastatic sites even after complete surgical resection. Furthermore, loss to follow-up in high-risk patients may permit undetected disease progression, supporting a more individualized approach to long-term surveillance. Imaging alone may fail to detect endobronchial disease, making early bronchoscopy essential for timely diagnosis and management.

Central airway obstruction can be caused by lung cancer and may severely diminish respiratory function to necessitate airway stenting. However, the mechanical properties of airway tissues remain poorly characterized, leading to a mismatch between stent mechanical behavior and airway compliance, which can reduce stent biocompatibility and clinical effectiveness. Such mismatches can result in abnormal stress transfer at the stent-airway interface and cause stent migration, local tissue irritation or inflammation, and impaired long-term performance. Predictive models are often used in treatment planning, however, without a comprehensive understanding of airway properties, advancements in modeling remain highly limited. In this study, we develop an experimental to numerical pipeline for identifying the mechanical properties of the human airway branching network, specifically the trachea, right bronchus, and left bronchus tissues. Biaxial planar tensile tests are used to capture the tissues' unique, anisotropic mechanical response in order to inform the computational routine-where inverse finite element analysis is employed to calibrate a Holzapfel-Gasser-Ogden constitutive model. To overcome the computational burden of traditional IFEA, a neural network (NN) surrogate model is trained to enable rapid material identification. We identify parameter values for the various tissues, such as C10 = 0.53 ± 0.25 kPa, k1 = 0.17 ± 0.30 kPa, k2 = 6.1 ± 2.0, and κ = 0.08 ± 0.01 for the trachea. Notably, this NN-approach reduced computational time from weeks to mere minutes, enabling fast material characterization. Thus, we also provide an efficient modeling framework and user-friendly MATLAB application for future studies. Ultimately, the findings here critically contribute to our current understanding of airway biomechanics and provide essential data for accurate modeling and optimization of airway stenting strategies.

Schwannomas are benign, slow-growing tumors that arise from Schwann cells of the peripheral nerve sheath. Pulmonary schwannomas are extremely uncommon, accounting for approximately 0.2% of all lung tumors and representing a small fraction of tracheobronchial neoplasms. We present a case involving a 49-year-old non-smoking male with a history of Crohn's disease who reported a persistent productive cough, dyspnea, and a subjective sensation of airway obstruction that did not improve with nebulized therapy. Chest CT revealed an endobronchial lesion obstructing the right mainstem bronchus. Flexible bronchoscopy demonstrated a vascular, pedunculated mass occupying approximately 80% of the bronchial lumen, and transbronchial biopsies were obtained. Histopathological and immunohistochemical analysis confirmed a diagnosis of schwannoma, with strong S100 positivity. The patient subsequently underwent rigid bronchoscopy with argon plasma coagulation, followed by complete tumor resection using a cryoprobe, resulting in successful airway restoration. This report highlights the importance of considering rare benign neoplasms in patients with persistent respiratory symptoms and emphasizes the role of bronchoscopic intervention in both diagnosis and definitive treatment.

Diagnosing intrathoracic tuberculosis (TB) in children under five years of age remains challenging. Clinical symptoms often overlap with those of other common childhood illnesses, and microbiological confirmation is frequently difficult to obtain in this age group. Despite advances in diagnostic technologies, few studies focus specifically on children younger than five years, the population in whom diagnosis is most complex. Intrathoracic lymphadenopathy on chest X-ray (CXR) is the hallmark radiological features of TB in this age group, but identification by trained physicians currently demonstrates only moderate diagnostic performance, with reported sensitivities ranging from 67% to 74% and specificities between 39% and 59%.

Primary pulmonary leiomyosarcoma (PPL) is the most common histological subtype of primary pulmonary sarcomas, although it is relatively rare. Herein, we report a case of a 76-year-old man with a mass arising in the hilar region of the right upper lobe of the lung and progressing to the right main bronchus, obstructing the bronchial lumen. He was admitted due to a five-day history of worsening respiratory distress and had a history of left upper lobectomy for primary lung adenocarcinoma. Bronchoscopic cryotherapy enabled the diagnosis of leiomyosarcoma of the lung and was effective in the recanalization of the right main bronchus obstruction caused by the tumor; it also improved his respiratory symptoms and hypoxia. Considering the risk of tumor invasion into the right main bronchus, the patient's advanced age, and his medical history of left upper lobectomy, surgical resection was deemed extremely difficult. He was treated with radiotherapy for local control followed by doxorubicin and ifosfamide combination chemotherapy, with improvement of chest computed tomography and bronchoscopic findings. Twelve months have passed since the start of radiotherapy for local control, and he has completed the 10th cycle of combination chemotherapy without any signs of tumor recurrence. This case demonstrates that radiotherapy for local control followed by combination chemotherapy with doxorubicin and ifosfamide may improve the prognosis of patients with unresectable PPL.

Capsule endoscopy (CE) aspiration is extremely rare (0.003%-0.013%) but potentially life-threatening. The CE is structurally challenging for standard bronchoscopic removal due to its large size, smooth surface and nonmetallic composition. While most aspirated capsules remain in the central airways, reports on peripheral impaction are limited. We report a case in which a CE was impacted deep within the right basal segmental bronchus of a man in his 70s. Conventional forceps manipulation failed because the capsule was completely impacted, preventing visibility beyond the obstruction. We successfully employed a two-step strategy: (1) disimpaction using a balloon catheter guided by fluoroscopy and (2) retrieval in the central airway using a retrieval loop net. This fluoroscopy-assisted two-step strategy provides a safe and reliable approach for retrieving structurally challenging foreign bodies in the peripheral airways.

A 66-year-old man presented with dyspnea and severe hypoxemia, requiring mechanical ventilation. Computed tomography revealed an obstruction of the left main bronchus by a bronchial tumor, thus prompting airway intervention to relieve the stenosis. A histopathological examination of the tumor revealed clear cytoplasm and hyalinized stroma, and rearrangement of EWSR1 was detected by a fluorescence in situ hybridization analysis. Comprehensive genomic profiling was performed because of the rarity of this case. GenMineTOP, capable of detecting the EWSR1::ATF1 fusion, contributed to a definitive diagnosis of hyalinizing clear cell carcinoma. Bronchoscopic airway intervention can serve as both a therapeutic and diagnostic procedure; GenMineTOP was useful in establishing a definitive diagnosis.

BACKGROUND Extracorporeal membrane oxygenation (ECMO) serves as a life-sustaining intervention for pediatric patients with severe, reversible respiratory or circulatory failure refractory to conventional therapies, providing temporary cardiopulmonary support to maintain oxygenation, perfusion, and hemodynamic stability. CASE REPORT Following a family argument, a 9-year-old boy fell from the seventh floor, with partial obstruction by a canopy. He presented with immediate loss of consciousness, absent voluntary motor activity, Kussmaul respirations, otorrhagia, and epistaxis. Initial computed tomography (CT) revealed high-attenuation nodules in the right main bronchus, right lower lobe bronchus. Despite endotracheal intubation and supportive measures, oxygenation remained refractory to correction, prompting interhospital transfer. On admission to our unit, imaging revealed high-attenuation opacities in the right middle bronchus and left lower lung. Multidisciplinary consultation was conducted. Under ECMO support, flexible bronchoscopy enabled retrieval of tooth fragments from the right upper lobe and an entire left maxillary first permanent molar from the left lower lobe. Postoperatively, ECMO was successfully discontinued, with the patient exhibiting stable vital signs, and subsequent management was continued. CONCLUSIONS The successful retrieval of dental fragments and an entire tooth via flexible bronchoscopy, facilitated by ECMO support, underscores the critical role of ECMO as a stabilizing platform enabling otherwise high-risk airway interventions in hemodynamically compromised pediatric trauma patients. This case illustrates the strategic implementation of venoarterial ECMO as a salvage therapy in the context of refractory hypoxemia and cardiopulmonary instability, rather than as a routine adjunct to flexible bronchoscopy procedures.

Bronchial adenoid cystic carcinoma (ACC) is a rare malignant tumor originating from salivary gland-type tissues of the tracheobronchial tree. It usually occurs in relatively young patients and is not strongly associated with tobacco exposure. Despite its slow-growing nature, ACC can behave aggressively locally, leading to significant airway obstruction. We report the case of a 47-year-old woman exposed to wood smoke who presented with progressive exertional dyspnea and unquantified weight loss. Chest computed tomography revealed a right hilar infiltrative lesion completely obstructing the right main bronchus, causing right lung atelectasis. Bronchoscopic evaluation demonstrated a highly vascularized endobronchial tumor. Histopathological examination confirmed ACC with cribriform pattern and perineural invasion. Pulmonary function tests indicated suitability for surgery. Considering the anatomical extent and absence of distant metastasis, the patient underwent right pneumonectomy with carinal resection. This case emphasizes the diagnostic challenges of ACC, the rationale for radical surgery in anatomically constrained tumors, and the importance of long-term multidisciplinary follow-up due to the risk of late local recurrence and delayed metastasis. Early recognition of persistent central airway symptoms is critical for optimizing patient outcomes.

BACKGROUND Traumatic bronchial obstruction resulting from blunt or penetrating chest trauma can lead to sudden respiratory failure; its diagnosis and management can be challenging. This report describes a case of traumatic complete occlusion of the left main bronchus and left lobar atelectasis, which was managed by temporary placement of a covered self-expandable metallic stent under fiberoptic bronchoscopic guidance. CASE REPORT A 37-year-old man presented with dyspnea after blunt chest trauma. Three days after admission, bronchoscopy confirmed complete occlusion of the left main bronchus; on the same day, initial recanalization with balloon dilation and cryoablation achieved only transient patency due to rapid granulation tissue regrowth. Two weeks after admission, a temporary covered self-expandable metallic stent was successfully placed based on multidisciplinary team recommendations. Within 48 hours, clinically significant lung re-expansion was observed. At 3.5 months after admission, the stent was removed. Follow-up imaging performed on the first postoperative day confirmed sustained lung expansion and airway patency. Nine months after admission, bronchoscopic evaluation indicated that the airway injury had entered a stable phase of healing. CONCLUSIONS Temporary placement of a covered self-expandable metallic stent is a viable and effective strategy for traumatic bronchial occlusion with recalcitrant granulation tissue. This minimally invasive approach facilitated anatomical and functional lung recovery, suggesting it can serve as an alternative to major surgery in cases of traumatic bronchial obstruction.

Teratocarcinosarcoma (TCS) is a rare, highly aggressive malignant neoplasm composed of epithelial, mesenchymal and neuroectodermal elements, occurring almost exclusively in the sinonasal region. Primary involvement of the tracheobronchial tree or carina has not been previously reported. We describe a 55-year-old male chronic smoker who presented with cough, progressive dyspnea and haemoptysis. Computed tomography revealed a lobulated soft-tissue mass in the distal trachea overhanging the carina, extending into both main bronchi, causing significant airway obstruction. Bronchoscopy demonstrated greater than 80% bilateral luminal occlusion, necessitating urgent endobronchial debulking using rigid bronchoscopy, snare electrocautery, and cryotherapy. Histopathology with immunohistochemistry confirmed teratocarcinosarcoma. Positron emission tomography-computed tomography (PET-CT) showed metabolically active mediastinal and hilar lymph nodes. The patient was treated with chemoradiotherapy. Follow-up bronchoscopy at 6 months showed no recurrence, and the patient remains asymptomatic under surveillance for 4 years. This case represents the first reported carinal presentation of teratocarcinosarcoma, expands the anatomical spectrum of TCS and emphasizes the value of multimodality treatment for sustained disease control.

Foreign bodies in the airways are relatively common in preschool- and school-aged children. We report a rare case of the successful removal of a sharp metallic foreign body from the bronchus of a 12-year-old boy under combined inhalational and intravenous anesthesia without tracheal intubation. This report emphasizes the perioperative anesthetic strategies for foreign object removal. The patient presented with sudden-onset choking and hemoptysis. Chest computed tomography revealed a linear metallic foreign body measuring approximately 5 cm long in the left main bronchus. The foreign body was removed via rigid bronchoscopy under deep sedation maintained by a combination of inhalational and intravenous anesthesia while preserving spontaneous respiration. Intraoperative ventilation was controlled intermittently to ensure adequate oxygenation. Based on recent studies, we discuss key anesthetic considerations and risk-mitigation strategies for managing sharp bronchial foreign bodies in pediatric patients. This case highlights the importance of maintaining spontaneous respiration during bronchoscopy and tailoring anesthetic approaches to ensure safe outcomes, despite limited access to advanced airway technologies.