The amphicrine (endo-exocrine) cells in the human gut, with a short reference to amphicrine neoplasias

In the human gastrointestinal tract the amphicrine cells are described as a special form of endocrine cells. Depending on their behaviour under silver impregnation, they are divided into three subgroups: the mucoargentaffine, the mucoargyrophilic and the mucoargyrophobic cells. They were detected electron microscopically in 1969, but they were histologically verified and identified as mucus-excreting endocrine elements only in 1977. Since 1969 such cells have also been observed in normal and regenerating rat and mouse stomachs. Our own human material includes stomach (3 cases), appendix (12 cases), colon (1) and a series of amphicrine proliferations and tumours. Two cases of chronic gastritis and one chronic peptic ulcer with metaplastic and regenerating epithelium contained mucoargyrophilic cells with mucus below the nucleus in the atypical glands. The possibility of endocrine granules being sluiced out in the mucous grains is discussed. Of the appendices only two were normal (ages 6 and 7 years), 10 showed pathological changes: there were seven neurogenic appendicopathies (14-58 years), one lymphatic hyperplasia, and one hyperplasia of mucoargyrophobic cells with mucostasis. Mucoargentaffine cells far outnumbered the mucoargyrophilic and mucoargyrophobic cells. The mucus may have either an apical or basal location; in the latter case, paracrine secretion into the subepithelial lamina propria was seen. As neoplastic cells, the amphicrine cells form the rare amphicrine tumours (goblet-cell and muco-adenoid carcinoids) of the appendix and colon. They are also found in mucinous cystadenomas of the ovary [26], in the enteral type of a nasal carcinoma [27,28], and in a 5-HT-carcinoid of the ovary [15]. They are therefore to be regarded as a differentiation disorder of the endocrine cells under the pathological conditions of appendicopathy, hyperplasia, metaplasia and true neoplasias.