Asymptomatic solitary papilloma of the bronchus: review of occurrence in Japan.

A case of solitary papilloma of the bronchus is described, and 15 other cases occurring in Japan are reviewed. A 57 year old asymptomatic male was referred to our hospital because many squamous metaplastic cells with moderate atypia were observed in sputum cytology, twice in 3 months. The chest X-ray showed no abnormal findings. Endoscopic examination revealed a polypoid tumour at the bifurcation of the right B6a and B6b. The tumour was removed completely by endoscopic biopsy, and histological findings showed squamous papilloma. There has been no evidence of recurrence for 3 yrs. We are not aware of a previously reported case of bronchial papilloma without symptoms or abnormal shadow on chest X-ray. Considering the fact that malignant change was reported in only one case in Japan, and that there is a possibility of cancer subsequently developing at another location in the lung which might also require resection, lobectomy should be avoided if the tumour can be removed completely through endoscopy. If the lesion is limited to a small area in the bronchus, conservative treatment such as photodynamic therapy and/or yttrium aluminium garnet (YAG) laser vaporization might be sufficient to obtain a complete cure.