Melanosis coli. Changes in appearance when associated with colonic neoplasia
L. Morgenstern, L. Shemen, W. Allen, P. Amodeo and S. L. Michel
In 30 cases of colonic neoplasia associated with melanosis coli,
proliferating or neoplastic colonic epithelium was notable within the
melanotic colons by virtue of a striking absence of pigmentation.
Microscopically this characteristic was found to be due to an absence or
diminution of pigment-laden macrophages in the lamina propria underlying
such lesions. Therefore, the absence of pigment-laden macrophages can be
considered a marker for abnormally proliferating epithelium. This
characteristic may denote a cellular or humoral change mediated by
macrophages in association with neoplastic epithelium.
