A 20-year prospective study of plasma prolactin as a risk marker of breast cancer development

Published on Tuesday, 14 December 2021


Understanding how the timing of exposure to endogenous hormones influences cancer development is critical to elucidating disease etiology.

Prolactin increases proliferation and cell motility, processes important in later stage tumor development, suggesting that levels proximate (versus distant) to diagnosis may better predict risk. Thus, we calculated relative risks (RR) and 95% confidence intervals (CI) for prolactin levels on samples collected < 10 (proximate) versus ≥10 (distant) years before diagnosis in the Nurses' Health Study (NHS) and NHSII with breast cancer risk, including in a subset of NHS women providing two samples 10 years apart. We measured prolactin via immunoassay in cases diagnosed from 1990 to 2010 (NHS) and 1999 to 2009 (NHSII) and matched controls.

Overall, 2,468 cases and 4,021 controls had prolactin measured < 10 years and 953 cases and 1,339 controls >10 years before diagnosis/reference date.

There was an increased risk for higher proximate prolactin levels [RR, >15.7 vs. ≤8.1 ng/mL (i.e., top vs. bottom quartiles) = 1.20; 95% CI, 1.03-1.40; Ptrend = 0.005], but not for distant levels (RR = 0.97; Ptrend = 0.94); results were similar among women with two blood samples (Pinteraction, proximate vs. distant = 0.07). The positive association was stronger for ER(+) disease (RR = 1.28; Ptrend = 0.003) and postmenopausal women (RR = 1.37; Ptrend = 0.0002). Among postmenopausal women, the association was strongest for ER(+) disease (RR = 1.52) and lymph node-positive cases (RR = 1.63).

Our data suggest that prolactin levels measured < 10 years before diagnosis are most strongly associated with postmenopausal breast cancer risk, especially for ER(+) tumors and metastatic disease.

This corresponds with biologic data that prolactin is etiologically important in tumor promotion.


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See also:

- Official Web Site: The Di Bella Method;


- The Di Bella Method (A Fixed Part - Bromocriptine and/or Cabergoline);

- The Di Bella Method (A Fixed Part - Cyclophosphamide 50mg tablets and/or Hydroxyurea 500mg tablets, one or two per day);

- The Di Bella Method (A Fixed Part - Somatostatin, Octreotide, Sandostatin LAR, analogues and/or derivatives);

- Somatostatin in oncology, the overlooked evidences - In vitro, review and in vivo publications;

- Publication, 2018 Jul: Over-Expression of GH/GHR in Breast Cancer and Oncosuppressor Role of Somatostatin as a Physiological Inhibitor (from Di Bella's Foundation);

- Publication, 2018 Sep: The over-expression of GH/GHR in tumour tissues with respect to healthy ones confirms its oncogenic role and the consequent oncosuppressor role of its physiological inhibitor, somatostatin: a review of the literature (from Di Bella's Foundation);

- Publication, 2019 Aug: The Entrapment of Somatostatin in a Lipid Formulation: Retarded Release and Free Radical Reactivity (from Di Bella's Foundation);

- Publication, 2019 Sep: Effects of Somatostatin and Vitamin C on the Fatty Acid Profile of Breast Cancer Cell Membranes (from Di Bella's Foundation);

- Publication, 2019 Sep: Effects of somatostatin, curcumin, and quercetin on the fatty acid profile of breast cancer cell membranes (from Di Bella's Foundation);

- Publication, 2020 Sep: Two neuroendocrine G protein-coupled receptor molecules, somatostatin and melatonin: Physiology of signal transduction and therapeutic perspectives (from Di Bella's Foundation);


- The Synergism of Somatostatin, Melatonin, Vitamins Prolactin and Estrogen Inhibitors Increased Survival, Objective Response and Performance Status In 297 Cases of Breast Cancer;

- Complete objective response, stable for 5 years, with the Di Bella Method, of multiple-metastatic carcinoma of the breast;

- Evaluation of the safety and efficacy of the first-line treatment with somatostatin combined with melatonin, retinoids, vitamin D3, and low doses of cyclophosphamide in 20 cases of breast cancer: a preliminary report;

- The Di Bella Method (DBM) improved survival, objective response and performance status in a retrospective observational clinical study on 122 cases of breast cancer;

- Complete objective response to biological therapy of plurifocal breast carcinoma;

- The Di Bella Method (DBM) in the treatment of prostate cancer: a preliminary retrospective study of 16 patients and a review of the literature.