Adenoma of the bronchus is usually included among the benign tumors. Although bronchial adenoma is infrequently encountered, it is not rare. It comprises about 5% of all bronchial neoplasms detected by bronchoscopy.
For many years bronchial adenomata were not considered to have malignant potential, and as recently as 1941, Foster-Carter, in a review of bronchial adenomata stated that these tumors were entirely benign. Since that time, there have been reports of bronchial adenomata metastasizing to regional lymph nodes, bone marrow, and other organs. Nevertheless, the occurrence of distant metastasis from a bronchial adenoma remains an infrequent finding.
Adenoma of the bronchus is as common in females as in males. Seventy per cent give rise to symptoms in the third or fourth decade of life. The etiology of bronchial adenoma is not known with certainty, but the most prevalent hypothesis is that the tumor arises from the bronchial glands.
ROSENBLUTH J, LAVAL J, WEIL JV. Metastasis of Bronchial Adenoma to the Eye. AMA Arch Ophthalmol. 1960;63(1):47-50. doi:10.1001/archopht.1960.00950020049007