[A case of asymptomatic endobronchial lipoma followed for 4 years]

Bronchoscopy was performed on a 68-year-old male patient with pulmonary tuberculosis, and revealed a yellow smooth polypoid tumor in the lumen of the left upper division bronchus. The histopathological diagnosis of the biopsy specimen was endobronchial lipoma. Since the patient did not have any symptoms due to the lipoma, we performed treatment for tuberculosis and continued careful observation of the tumor. During the subsequent 4 years, the patient developed no complications such as obstructive pneumonia, and the size of the tumor under bronchoscopic observation did not change. Endobronchial lipoma is a very rare benign tumor. Almost all reported cases have undergone operation or endoscopic surgery. This case is the first that was followed over 4 years without surgical procedure. The findings of follow-up bronchoscopic examination suggest that the growth rate of endobronchial lipoma is very slow. Furthermore, we reviewed 36 cases of endobronchial lipoma in the Japanese literature, including our case. Smoking seems to have a strong relation to the occurrence of the tumor. It is noteworthy that 6 cases had separate malignancies, but the direct relationship between endobronchial lipoma and such malignancies is unclear.