喉頭腺癌3例—喉頭に腺癌はなぜ少ないか

ADENOCARCINOMA OF THE LARYNX

　I．緒言

　喉頭に腺癌がきわめて少ないという臨床事実はわが国はもちろん世界の統計が示す通りである^3）。わが国でも国立がんセンター^8）の522例中4例（0.7％），著者の1100例中3例（0.3％）の統計の示すごとく1％以下となつている。

　他の呼吸器癌の鼻・副鼻腔癌では酒井^6）の統計によると744例中腺癌27例（3％），肺癌では岡田^5）の統計によると517例中，扁平上皮癌45％，腺癌33％となつている。肺癌ではわが国は欧米に比して，腺癌が多い。

　Adenocarcinoma of the larynx is a rare disease. There were only three cases of adenocarcinoma among the 1,100 cases of laryngeal cancers which the authors experienced. The focus of the disease are in the supraglottic region consisting of 2 cases of adenoid cystic carcinoma and a case of papillary adenocarcinoma.

　From histogenetie point of view the authors expound the reason of not finding many cases of adenocarcinoma in the larynx may be dependent upon the following facts:

　The squamous metaplasia progressing with aging of the individual ordinarily would cause glandular atrophy. However, in the columnar epithelium of the supraglotic region the basal cells do not show hyperplasia and by electronic microscopic examination of the laryngeal cancer tissues the presence of adenoacanthoma is not recognized.