Abstract
Metaplasia of the respiratory epithelium mayoccur in two forms: squamous metaplasia of thebronchial epithelium and adenomatous metaplasia of the alveolar epithelium.
Squamous metaplasia is the replacement of thebronchial mucosa by squamous epithelium, and theresult of abnormal multiplication of basal cells.
Adenomatous metaplasia is the replacement of thealveolar lining by cuboidal cells, and the result ofabnormal proliferation of type B alveolar epithelialcells.
Differentiation of small anaplastic cancer cellsfrom basal cells of the bronchial epithelium issummarized in Table 1.
Differentiation of squamous cancer cells fromsquamous cells originating in squamous metaplasiais summarized in Table 2.
Differentiation of adenocarcinoma cells from adenomatous cells originating in adenomatous metaplasia is summarized in Table 3.
