[The estrogen dependence of the pregnancy associated alpha glycoprotein "SP3" and its occurrence in sera of patients with various malignant and benign diseases].

The pregnancy associated alpha-2-glycoprotein "SP3" is a macroprotein; the serum concentration of which is markedly enhanced by the increase of endogenous and exogenous estrogen. As regards the bronchial and uterine cancer the frequent presence of enhanced SP3 serum concentrations in tumour patients can be explained by an enhanced production of endogenous estrogen. This enhanced production has been described in literature. SP3 does not occur in healthy men and women without application of estrogen. In 26% of the cases it can be proved in cases of benign disease and in 52% in malignant cases having received no therapy of estrogen.