The histogenesis of carcinoid tumours of the rectum

Mucin-producing atypical bronchial carcinoid.

“…On light microscopy the tumours resemble those found in the appendix (Dische, 1968;Hernandez and Reid, 1969), stomach, colon, and rectum (Gibbs, 1963;Hernandez and Reid, 1969) but differ significantly from the goblet-cell carcinoids of the appendix (Klein, 1974;Subbuswamy et al, 1974;Abt and Carter, 1976;Haqqani and Williams, 1977;McDonald and Hourihane, 1977). The presence of a glandular or tubular pattern in the tumours is well recognised (Weiss and Ingram, 1961;Fu et al, 1974), and in a number of cases simple and complex gland lumina with bordering microvilli have been demonstrated on electron microscopy (Fu et al, 1974;Bell et al, 1975;Sonksen et al, 1976).…”

Rectal adenocarcinoid with lymph node metastasis

“…Terms such as adenocarcinoid or composite carcinoid have been used to describe these tumors. 6,7 Adenocarcinoid may be classified into three subtypes: (i) goblet cell; (ii) tubular; and (iii) mixed type. 1 The histologic features in the current case appeared to be different from the goblet cell type because the latter is composed mostly of goblet cells or signet ring‐like cells.…”

Carcinoid tumour of the ampulla of Vater associated with cutaneous neurofibromatosis

“…Ectodermal origins have been proposed (Raiford, 1932;Boyd, 1960) while others have suggested endodermal or mesenchymal sources from the intestinal crypt cells (Foley and Davis, 1965;Azzopardi and Pollock, 1963;Gibbs, 1962;Williams and Sandler, 1963;Popoff, 1939;Masson, 1928). More recently, Pearse has characterized carcinoids as arising from cells belonging to the APUD (amine precursor uptake and decarboxylating) cell system, and considers that, while there is some degree of overlap with the endodermal 'parakrine' system described by Feyrter (1954), APUD cells must be regarded as derivative of the neural crest (Pearse and Welbourn, 1973).…”