Is Endogenous Prolactin, Not Endocrine Prolactin, Responsible for Hyperparathyroidism in Breast Cancer Patients?

Breast cancer is the most common site-dependentcancer among females and the main cause of deathdue to malignancy in females aged 40-44 years. Thisillness is responsible for 33% of all gynecologicalmalignancies and 20% of all females' mortality.According to the reported statistics in the USA, theprobability of developing breast cancer is one inevery 8 women.1Hypercalcemia in patients with breast cancer isgenerally considered a result of osteolytic metastasisor circulating tumor derived products. In suchsituations, severely depressed plasma parathormone(PTH) is expected. Hypercalcemia in malign- 2,3ancies is multifactorial, and results from acombination of increased bone resorption associatedwith decreased renal excretion of the increasedextra-cellular fluid calcium. One of the most 4frequent etiologies of hypercalcemia is hyperparathyroidismwhich is usually neglected in breastcancer patients, while recent studies have shownincreased incidence of primary hyperparathyroidismin breast cancer patients regardless ofclinical staging or anti-tumor therapy.