ABSTRACT
The role played by PRL in human breast cancer is still obscure. Several observations, however, demonstrated that antitumor therapies for breast cancer are associated with changes in PRL secretion, clinical significance of which remains to be determined. The present investigation was carried out to further clarify the effects of mastectomy on PRL levels in breast cancer women. The study included 34 patients at clinical stage T1-2N0-2M0 treated with radical mastectomy. In each patient, venous blood samples were drawn before, and 15 days, 1 month, 45 days, 2 months and 3 months after surgery to determine PRL serum levels. As controls, 14 women surgically treated for reasons other than neoplastic disease were included in the study. Mastectomy was followed by hyperprolactinemia in 18 of the 34 cases (52.9%). PRL remained elevated for at least 1 month, and it became normal within 2 months. On the contrary, no PRL increase was seen in controls. Among breast cancer women, PRL increase was irrespective of the type of surgery, the histology of the tumor and the menopausal status. In contrast, PRL increase was significantly higher in patients without node involvement and with negative hormonal receptors, with respect to that observed in cases with node involvement and positive receptors, respectively. The mechanisms by which mastectomy induces enhanced PRL secretion are still obscure. They might depend, however, on changes in feed-back systems operating in the regulation of PRL secretion, due to the removal of a target organ for PRL itself. Longitudinal studies, by evaluating the percentage of relapse either in patients with surgery-induced hyperprolactinemia or in those with normal hormonal values, will be needed to clarify the prognostic significance of the enhanced PRL secretion induced by mastectomy.
