HORMONES AND CARCINOGENESIS

Hormones are important regulators of growth. By stimulating proliferat ion, hormones may increase the risk of mutation and at the same time s timulate the replication of the mutated cell. Thus, hormones are compl ete carcinogens. A direct carcinogenic effect of oestrogen in man is k nown from the occurrence of vaginal carcinomas in girls born of mother s who were treated with oestrogen during pregnancy. There are also exp erimental animal studies indicating that even peptide hormones may ind uce malignant tumours. An excellent example is the so-called enterochr omaffin-like cell (ECL-cell) carcinoid of the stomach, which is caused by hypergastrinaemia and where the pathogenesis is diffuse hyperplasi a, linear and nodular hyperplasia, dysplasia (with micronodules), intr amucosal carcinoid, and invasive carcinoid. This sequence of events ca n be followed not only histopathologically but also by means of image DNA cytometry of the nuclei of the ECL-cells. As soon as clear-cut neo plasia is present, the cytometric DNA distribution pattern switches fr om the normal diploid type to an aneuploid one. The hyperplastic lesio ns are all reversible, as soon as the hypergastrinaemia is eliminated.