DISCUSSION
Benign tracheobronchial tumors are sporadic tumors representing only 0.2% of all pulmonary tumors in the United States.4The two most common types of benign pulmonary tumors are hamartomas and papillomas, and leiomyomas, lipomas, chondromas, and neurogenic tumors can present as less frequent benign neoplasms.1 Most benign pulmonary tumors are slow-growing and asymptomatic and often remain undiagnosed before they cause bronchial obstruction or mass effects on surrounding organs. The diagnosis of these tumors is often challenging because the symptoms and signs are non-specific, and a simple chest X-ray fails to present remarkable findings. Thus, they are frequently misdiagnosed as more common causes of chronic cough or dyspnea, such as chronic obstructive bronchitis, asthma, and bronchogenic carcinomas.2, 3, 5 Because most of the symptoms of bronchial tumors are primarily caused by their growth and complications to adjacent structures, early detection and treatment are clinically significant.
Bronchial chondromas  are very rare benign tumors arising from bronchial cartilage.1 Because they are often misclassified as hamartomas, the most common type of endobronchial neoplasm, the accurate incidence of bronchial chondroma is still unclear yet.1 In contrast to hamartomas, endobronchial chondromas have a distinct pathology consisting of calcified/ossified cartilaginous components without adipose tissue, smooth muscle, epithelial, and stromal elements characteristics of hamartomas.6, 7 Well-differentiated chondrosarcomas can resemble chondromas,4, 8.they can be differentiated by the presence of tissue invasion or mitosis,9 and clinicians should also evaluate the possibility of lung metastasis from other skeletal systems considering higher incidence.
Bronchial chondromas are occasionally present as a component of the Carney triad characterized by the simultaneous presence of gastric epithelioid leiomyoblastoma, extra-adrenal paragangliomas, and pulmonary chondroma.10 In this case, after his tumor was defined as an endobronchial enchondroma, in consideration of the presence of the Carney triad, we performed a gastroscopic examination to evaluate the presence of the gastric leiomyoblastoma. We did complete history-taking and physical examination again to assess symptoms and signs representing paragangliomas. However, there was no evidence of the Carney triad, and the tumor was eventually diagnosed as an isolated endobronchial enchondroma, which is extremely rare among pulmonary chondromas.
Although there is no consensus of the best treatment approach to bronchial chondroma, most treatments were performed by complete excision with bronchoscopy or surgery including VATS or open thoracotomy. The choice of therapy should be considered in each case based on the tumor’s operability, size, type, and location.10 Even if just a small number of cases were reported, none of the patients died or had severe complications regardless of the treatment options, and recurrence after treatment was very low. There was a report that only one presented recurrence among 23 cases of treated cases between 1945 and 1980.9 In addition, there was a report presenting the recurrent tracheal chondroma with the sarcomatous transformation.12, 13 Considering the low risk of treatment morbidity, mortality, and recurrence, and potential risk of malignant transformation and structural destruction of adjacent organs, prompt and proper treatment options for complete excision should be considered individually based on the tumor situation.
In the current case, when the patient visited the pulmonary clinic for the first time, he had a chronic cough for more than six months, and it was initially considered the effect of cigarette smoking by him. Even if most benign bronchial tumors are asymptomatic, some patients may have symptoms, such as intractable cough or hemoptysis, suggesting chronic airway diseases.2, 3, 14 After excising the tumor entirely by the lobectomy procedure, his cough disappeared one month after discharge from the hospital. This case is a good example emphasizing the benefit of early recognition and adequate treatment of bronchial tumors to clinicians.